diff options
Diffstat (limited to 'src/html/template')
36 files changed, 10875 insertions, 0 deletions
diff --git a/src/html/template/attr.go b/src/html/template/attr.go new file mode 100644 index 0000000..22922e6 --- /dev/null +++ b/src/html/template/attr.go @@ -0,0 +1,175 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package template + +import ( + "strings" +) + +// attrTypeMap[n] describes the value of the given attribute. +// If an attribute affects (or can mask) the encoding or interpretation of +// other content, or affects the contents, idempotency, or credentials of a +// network message, then the value in this map is contentTypeUnsafe. +// This map is derived from HTML5, specifically +// https://www.w3.org/TR/html5/Overview.html#attributes-1 +// as well as "%URI"-typed attributes from +// https://www.w3.org/TR/html4/index/attributes.html +var attrTypeMap = map[string]contentType{ + "accept": contentTypePlain, + "accept-charset": contentTypeUnsafe, + "action": contentTypeURL, + "alt": contentTypePlain, + "archive": contentTypeURL, + "async": contentTypeUnsafe, + "autocomplete": contentTypePlain, + "autofocus": contentTypePlain, + "autoplay": contentTypePlain, + "background": contentTypeURL, + "border": contentTypePlain, + "checked": contentTypePlain, + "cite": contentTypeURL, + "challenge": contentTypeUnsafe, + "charset": contentTypeUnsafe, + "class": contentTypePlain, + "classid": contentTypeURL, + "codebase": contentTypeURL, + "cols": contentTypePlain, + "colspan": contentTypePlain, + "content": contentTypeUnsafe, + "contenteditable": contentTypePlain, + "contextmenu": contentTypePlain, + "controls": contentTypePlain, + "coords": contentTypePlain, + "crossorigin": contentTypeUnsafe, + "data": contentTypeURL, + "datetime": contentTypePlain, + "default": contentTypePlain, + "defer": contentTypeUnsafe, + "dir": contentTypePlain, + "dirname": contentTypePlain, + "disabled": contentTypePlain, + "draggable": contentTypePlain, + "dropzone": contentTypePlain, + "enctype": contentTypeUnsafe, + "for": contentTypePlain, + "form": contentTypeUnsafe, + "formaction": contentTypeURL, + "formenctype": contentTypeUnsafe, + "formmethod": contentTypeUnsafe, + "formnovalidate": contentTypeUnsafe, + "formtarget": contentTypePlain, + "headers": contentTypePlain, + "height": contentTypePlain, + "hidden": contentTypePlain, + "high": contentTypePlain, + "href": contentTypeURL, + "hreflang": contentTypePlain, + "http-equiv": contentTypeUnsafe, + "icon": contentTypeURL, + "id": contentTypePlain, + "ismap": contentTypePlain, + "keytype": contentTypeUnsafe, + "kind": contentTypePlain, + "label": contentTypePlain, + "lang": contentTypePlain, + "language": contentTypeUnsafe, + "list": contentTypePlain, + "longdesc": contentTypeURL, + "loop": contentTypePlain, + "low": contentTypePlain, + "manifest": contentTypeURL, + "max": contentTypePlain, + "maxlength": contentTypePlain, + "media": contentTypePlain, + "mediagroup": contentTypePlain, + "method": contentTypeUnsafe, + "min": contentTypePlain, + "multiple": contentTypePlain, + "name": contentTypePlain, + "novalidate": contentTypeUnsafe, + // Skip handler names from + // https://www.w3.org/TR/html5/webappapis.html#event-handlers-on-elements,-document-objects,-and-window-objects + // since we have special handling in attrType. + "open": contentTypePlain, + "optimum": contentTypePlain, + "pattern": contentTypeUnsafe, + "placeholder": contentTypePlain, + "poster": contentTypeURL, + "profile": contentTypeURL, + "preload": contentTypePlain, + "pubdate": contentTypePlain, + "radiogroup": contentTypePlain, + "readonly": contentTypePlain, + "rel": contentTypeUnsafe, + "required": contentTypePlain, + "reversed": contentTypePlain, + "rows": contentTypePlain, + "rowspan": contentTypePlain, + "sandbox": contentTypeUnsafe, + "spellcheck": contentTypePlain, + "scope": contentTypePlain, + "scoped": contentTypePlain, + "seamless": contentTypePlain, + "selected": contentTypePlain, + "shape": contentTypePlain, + "size": contentTypePlain, + "sizes": contentTypePlain, + "span": contentTypePlain, + "src": contentTypeURL, + "srcdoc": contentTypeHTML, + "srclang": contentTypePlain, + "srcset": contentTypeSrcset, + "start": contentTypePlain, + "step": contentTypePlain, + "style": contentTypeCSS, + "tabindex": contentTypePlain, + "target": contentTypePlain, + "title": contentTypePlain, + "type": contentTypeUnsafe, + "usemap": contentTypeURL, + "value": contentTypeUnsafe, + "width": contentTypePlain, + "wrap": contentTypePlain, + "xmlns": contentTypeURL, +} + +// attrType returns a conservative (upper-bound on authority) guess at the +// type of the lowercase named attribute. +func attrType(name string) contentType { + if strings.HasPrefix(name, "data-") { + // Strip data- so that custom attribute heuristics below are + // widely applied. + // Treat data-action as URL below. + name = name[5:] + } else if colon := strings.IndexRune(name, ':'); colon != -1 { + if name[:colon] == "xmlns" { + return contentTypeURL + } + // Treat svg:href and xlink:href as href below. + name = name[colon+1:] + } + if t, ok := attrTypeMap[name]; ok { + return t + } + // Treat partial event handler names as script. + if strings.HasPrefix(name, "on") { + return contentTypeJS + } + + // Heuristics to prevent "javascript:..." injection in custom + // data attributes and custom attributes like g:tweetUrl. + // https://www.w3.org/TR/html5/dom.html#embedding-custom-non-visible-data-with-the-data-*-attributes + // "Custom data attributes are intended to store custom data + // private to the page or application, for which there are no + // more appropriate attributes or elements." + // Developers seem to store URL content in data URLs that start + // or end with "URI" or "URL". + if strings.Contains(name, "src") || + strings.Contains(name, "uri") || + strings.Contains(name, "url") { + return contentTypeURL + } + return contentTypePlain +} diff --git a/src/html/template/attr_string.go b/src/html/template/attr_string.go new file mode 100644 index 0000000..babe70c --- /dev/null +++ b/src/html/template/attr_string.go @@ -0,0 +1,16 @@ +// Code generated by "stringer -type attr"; DO NOT EDIT. + +package template + +import "strconv" + +const _attr_name = "attrNoneattrScriptattrScriptTypeattrStyleattrURLattrSrcset" + +var _attr_index = [...]uint8{0, 8, 18, 32, 41, 48, 58} + +func (i attr) String() string { + if i >= attr(len(_attr_index)-1) { + return "attr(" + strconv.FormatInt(int64(i), 10) + ")" + } + return _attr_name[_attr_index[i]:_attr_index[i+1]] +} diff --git a/src/html/template/clone_test.go b/src/html/template/clone_test.go new file mode 100644 index 0000000..7cb1b9c --- /dev/null +++ b/src/html/template/clone_test.go @@ -0,0 +1,279 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package template + +import ( + "bytes" + "errors" + "fmt" + "io" + "strings" + "sync" + "testing" + "text/template/parse" +) + +func TestAddParseTreeHTML(t *testing.T) { + root := Must(New("root").Parse(`{{define "a"}} {{.}} {{template "b"}} {{.}} "></a>{{end}}`)) + tree, err := parse.Parse("t", `{{define "b"}}<a href="{{end}}`, "", "", nil, nil) + if err != nil { + t.Fatal(err) + } + added := Must(root.AddParseTree("b", tree["b"])) + b := new(bytes.Buffer) + err = added.ExecuteTemplate(b, "a", "1>0") + if err != nil { + t.Fatal(err) + } + if got, want := b.String(), ` 1>0 <a href=" 1%3e0 "></a>`; got != want { + t.Errorf("got %q want %q", got, want) + } +} + +func TestClone(t *testing.T) { + // The {{.}} will be executed with data "<i>*/" in different contexts. + // In the t0 template, it will be in a text context. + // In the t1 template, it will be in a URL context. + // In the t2 template, it will be in a JavaScript context. + // In the t3 template, it will be in a CSS context. + const tmpl = `{{define "a"}}{{template "lhs"}}{{.}}{{template "rhs"}}{{end}}` + b := new(bytes.Buffer) + + // Create an incomplete template t0. + t0 := Must(New("t0").Parse(tmpl)) + + // Clone t0 as t1. + t1 := Must(t0.Clone()) + Must(t1.Parse(`{{define "lhs"}} <a href=" {{end}}`)) + Must(t1.Parse(`{{define "rhs"}} "></a> {{end}}`)) + + // Execute t1. + b.Reset() + if err := t1.ExecuteTemplate(b, "a", "<i>*/"); err != nil { + t.Fatal(err) + } + if got, want := b.String(), ` <a href=" %3ci%3e*/ "></a> `; got != want { + t.Errorf("t1: got %q want %q", got, want) + } + + // Clone t0 as t2. + t2 := Must(t0.Clone()) + Must(t2.Parse(`{{define "lhs"}} <p onclick="javascript: {{end}}`)) + Must(t2.Parse(`{{define "rhs"}} "></p> {{end}}`)) + + // Execute t2. + b.Reset() + if err := t2.ExecuteTemplate(b, "a", "<i>*/"); err != nil { + t.Fatal(err) + } + if got, want := b.String(), ` <p onclick="javascript: "\u003ci\u003e*/" "></p> `; got != want { + t.Errorf("t2: got %q want %q", got, want) + } + + // Clone t0 as t3, but do not execute t3 yet. + t3 := Must(t0.Clone()) + Must(t3.Parse(`{{define "lhs"}} <style> {{end}}`)) + Must(t3.Parse(`{{define "rhs"}} </style> {{end}}`)) + + // Complete t0. + Must(t0.Parse(`{{define "lhs"}} ( {{end}}`)) + Must(t0.Parse(`{{define "rhs"}} ) {{end}}`)) + + // Clone t0 as t4. Redefining the "lhs" template should not fail. + t4 := Must(t0.Clone()) + if _, err := t4.Parse(`{{define "lhs"}} OK {{end}}`); err != nil { + t.Errorf(`redefine "lhs": got err %v want nil`, err) + } + // Cloning t1 should fail as it has been executed. + if _, err := t1.Clone(); err == nil { + t.Error("cloning t1: got nil err want non-nil") + } + // Redefining the "lhs" template in t1 should fail as it has been executed. + if _, err := t1.Parse(`{{define "lhs"}} OK {{end}}`); err == nil { + t.Error(`redefine "lhs": got nil err want non-nil`) + } + + // Execute t0. + b.Reset() + if err := t0.ExecuteTemplate(b, "a", "<i>*/"); err != nil { + t.Fatal(err) + } + if got, want := b.String(), ` ( <i>*/ ) `; got != want { + t.Errorf("t0: got %q want %q", got, want) + } + + // Clone t0. This should fail, as t0 has already executed. + if _, err := t0.Clone(); err == nil { + t.Error(`t0.Clone(): got nil err want non-nil`) + } + + // Similarly, cloning sub-templates should fail. + if _, err := t0.Lookup("a").Clone(); err == nil { + t.Error(`t0.Lookup("a").Clone(): got nil err want non-nil`) + } + if _, err := t0.Lookup("lhs").Clone(); err == nil { + t.Error(`t0.Lookup("lhs").Clone(): got nil err want non-nil`) + } + + // Execute t3. + b.Reset() + if err := t3.ExecuteTemplate(b, "a", "<i>*/"); err != nil { + t.Fatal(err) + } + if got, want := b.String(), ` <style> ZgotmplZ </style> `; got != want { + t.Errorf("t3: got %q want %q", got, want) + } +} + +func TestTemplates(t *testing.T) { + names := []string{"t0", "a", "lhs", "rhs"} + // Some template definitions borrowed from TestClone. + const tmpl = ` + {{define "a"}}{{template "lhs"}}{{.}}{{template "rhs"}}{{end}} + {{define "lhs"}} <a href=" {{end}} + {{define "rhs"}} "></a> {{end}}` + t0 := Must(New("t0").Parse(tmpl)) + templates := t0.Templates() + if len(templates) != len(names) { + t.Errorf("expected %d templates; got %d", len(names), len(templates)) + } + for _, name := range names { + found := false + for _, tmpl := range templates { + if name == tmpl.text.Name() { + found = true + break + } + } + if !found { + t.Error("could not find template", name) + } + } +} + +// This used to crash; https://golang.org/issue/3281 +func TestCloneCrash(t *testing.T) { + t1 := New("all") + Must(t1.New("t1").Parse(`{{define "foo"}}foo{{end}}`)) + t1.Clone() +} + +// Ensure that this guarantee from the docs is upheld: +// "Further calls to Parse in the copy will add templates +// to the copy but not to the original." +func TestCloneThenParse(t *testing.T) { + t0 := Must(New("t0").Parse(`{{define "a"}}{{template "embedded"}}{{end}}`)) + t1 := Must(t0.Clone()) + Must(t1.Parse(`{{define "embedded"}}t1{{end}}`)) + if len(t0.Templates())+1 != len(t1.Templates()) { + t.Error("adding a template to a clone added it to the original") + } + // double check that the embedded template isn't available in the original + err := t0.ExecuteTemplate(io.Discard, "a", nil) + if err == nil { + t.Error("expected 'no such template' error") + } +} + +// https://golang.org/issue/5980 +func TestFuncMapWorksAfterClone(t *testing.T) { + funcs := FuncMap{"customFunc": func() (string, error) { + return "", errors.New("issue5980") + }} + + // get the expected error output (no clone) + uncloned := Must(New("").Funcs(funcs).Parse("{{customFunc}}")) + wantErr := uncloned.Execute(io.Discard, nil) + + // toClone must be the same as uncloned. It has to be recreated from scratch, + // since cloning cannot occur after execution. + toClone := Must(New("").Funcs(funcs).Parse("{{customFunc}}")) + cloned := Must(toClone.Clone()) + gotErr := cloned.Execute(io.Discard, nil) + + if wantErr.Error() != gotErr.Error() { + t.Errorf("clone error message mismatch want %q got %q", wantErr, gotErr) + } +} + +// https://golang.org/issue/16101 +func TestTemplateCloneExecuteRace(t *testing.T) { + const ( + input = `<title>{{block "a" .}}a{{end}}</title><body>{{block "b" .}}b{{end}}<body>` + overlay = `{{define "b"}}A{{end}}` + ) + outer := Must(New("outer").Parse(input)) + tmpl := Must(Must(outer.Clone()).Parse(overlay)) + + var wg sync.WaitGroup + for i := 0; i < 10; i++ { + wg.Add(1) + go func() { + defer wg.Done() + for i := 0; i < 100; i++ { + if err := tmpl.Execute(io.Discard, "data"); err != nil { + panic(err) + } + } + }() + } + wg.Wait() +} + +func TestTemplateCloneLookup(t *testing.T) { + // Template.escape makes an assumption that the template associated + // with t.Name() is t. Check that this holds. + tmpl := Must(New("x").Parse("a")) + tmpl = Must(tmpl.Clone()) + if tmpl.Lookup(tmpl.Name()) != tmpl { + t.Error("after Clone, tmpl.Lookup(tmpl.Name()) != tmpl") + } +} + +func TestCloneGrowth(t *testing.T) { + tmpl := Must(New("root").Parse(`<title>{{block "B". }}Arg{{end}}</title>`)) + tmpl = Must(tmpl.Clone()) + Must(tmpl.Parse(`{{define "B"}}Text{{end}}`)) + for i := 0; i < 10; i++ { + tmpl.Execute(io.Discard, nil) + } + if len(tmpl.DefinedTemplates()) > 200 { + t.Fatalf("too many templates: %v", len(tmpl.DefinedTemplates())) + } +} + +// https://golang.org/issue/17735 +func TestCloneRedefinedName(t *testing.T) { + const base = ` +{{ define "a" -}}<title>{{ template "b" . -}}</title>{{ end -}} +{{ define "b" }}{{ end -}} +` + const page = `{{ template "a" . }}` + + t1 := Must(New("a").Parse(base)) + + for i := 0; i < 2; i++ { + t2 := Must(t1.Clone()) + t2 = Must(t2.New(fmt.Sprintf("%d", i)).Parse(page)) + err := t2.Execute(io.Discard, nil) + if err != nil { + t.Fatal(err) + } + } +} + +// Issue 24791. +func TestClonePipe(t *testing.T) { + a := Must(New("a").Parse(`{{define "a"}}{{range $v := .A}}{{$v}}{{end}}{{end}}`)) + data := struct{ A []string }{A: []string{"hi"}} + b := Must(a.Clone()) + var buf strings.Builder + if err := b.Execute(&buf, &data); err != nil { + t.Fatal(err) + } + if got, want := buf.String(), "hi"; got != want { + t.Errorf("got %q want %q", got, want) + } +} diff --git a/src/html/template/content.go b/src/html/template/content.go new file mode 100644 index 0000000..6ba87a9 --- /dev/null +++ b/src/html/template/content.go @@ -0,0 +1,185 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package template + +import ( + "fmt" + "reflect" +) + +// Strings of content from a trusted source. +type ( + // CSS encapsulates known safe content that matches any of: + // 1. The CSS3 stylesheet production, such as `p { color: purple }`. + // 2. The CSS3 rule production, such as `a[href=~"https:"].foo#bar`. + // 3. CSS3 declaration productions, such as `color: red; margin: 2px`. + // 4. The CSS3 value production, such as `rgba(0, 0, 255, 127)`. + // See https://www.w3.org/TR/css3-syntax/#parsing and + // https://web.archive.org/web/20090211114933/http://w3.org/TR/css3-syntax#style + // + // Use of this type presents a security risk: + // the encapsulated content should come from a trusted source, + // as it will be included verbatim in the template output. + CSS string + + // HTML encapsulates a known safe HTML document fragment. + // It should not be used for HTML from a third-party, or HTML with + // unclosed tags or comments. The outputs of a sound HTML sanitizer + // and a template escaped by this package are fine for use with HTML. + // + // Use of this type presents a security risk: + // the encapsulated content should come from a trusted source, + // as it will be included verbatim in the template output. + HTML string + + // HTMLAttr encapsulates an HTML attribute from a trusted source, + // for example, ` dir="ltr"`. + // + // Use of this type presents a security risk: + // the encapsulated content should come from a trusted source, + // as it will be included verbatim in the template output. + HTMLAttr string + + // JS encapsulates a known safe EcmaScript5 Expression, for example, + // `(x + y * z())`. + // Template authors are responsible for ensuring that typed expressions + // do not break the intended precedence and that there is no + // statement/expression ambiguity as when passing an expression like + // "{ foo: bar() }\n['foo']()", which is both a valid Expression and a + // valid Program with a very different meaning. + // + // Use of this type presents a security risk: + // the encapsulated content should come from a trusted source, + // as it will be included verbatim in the template output. + // + // Using JS to include valid but untrusted JSON is not safe. + // A safe alternative is to parse the JSON with json.Unmarshal and then + // pass the resultant object into the template, where it will be + // converted to sanitized JSON when presented in a JavaScript context. + JS string + + // JSStr encapsulates a sequence of characters meant to be embedded + // between quotes in a JavaScript expression. + // The string must match a series of StringCharacters: + // StringCharacter :: SourceCharacter but not `\` or LineTerminator + // | EscapeSequence + // Note that LineContinuations are not allowed. + // JSStr("foo\\nbar") is fine, but JSStr("foo\\\nbar") is not. + // + // Use of this type presents a security risk: + // the encapsulated content should come from a trusted source, + // as it will be included verbatim in the template output. + JSStr string + + // URL encapsulates a known safe URL or URL substring (see RFC 3986). + // A URL like `javascript:checkThatFormNotEditedBeforeLeavingPage()` + // from a trusted source should go in the page, but by default dynamic + // `javascript:` URLs are filtered out since they are a frequently + // exploited injection vector. + // + // Use of this type presents a security risk: + // the encapsulated content should come from a trusted source, + // as it will be included verbatim in the template output. + URL string + + // Srcset encapsulates a known safe srcset attribute + // (see https://w3c.github.io/html/semantics-embedded-content.html#element-attrdef-img-srcset). + // + // Use of this type presents a security risk: + // the encapsulated content should come from a trusted source, + // as it will be included verbatim in the template output. + Srcset string +) + +type contentType uint8 + +const ( + contentTypePlain contentType = iota + contentTypeCSS + contentTypeHTML + contentTypeHTMLAttr + contentTypeJS + contentTypeJSStr + contentTypeURL + contentTypeSrcset + // contentTypeUnsafe is used in attr.go for values that affect how + // embedded content and network messages are formed, vetted, + // or interpreted; or which credentials network messages carry. + contentTypeUnsafe +) + +// indirect returns the value, after dereferencing as many times +// as necessary to reach the base type (or nil). +func indirect(a interface{}) interface{} { + if a == nil { + return nil + } + if t := reflect.TypeOf(a); t.Kind() != reflect.Ptr { + // Avoid creating a reflect.Value if it's not a pointer. + return a + } + v := reflect.ValueOf(a) + for v.Kind() == reflect.Ptr && !v.IsNil() { + v = v.Elem() + } + return v.Interface() +} + +var ( + errorType = reflect.TypeOf((*error)(nil)).Elem() + fmtStringerType = reflect.TypeOf((*fmt.Stringer)(nil)).Elem() +) + +// indirectToStringerOrError returns the value, after dereferencing as many times +// as necessary to reach the base type (or nil) or an implementation of fmt.Stringer +// or error, +func indirectToStringerOrError(a interface{}) interface{} { + if a == nil { + return nil + } + v := reflect.ValueOf(a) + for !v.Type().Implements(fmtStringerType) && !v.Type().Implements(errorType) && v.Kind() == reflect.Ptr && !v.IsNil() { + v = v.Elem() + } + return v.Interface() +} + +// stringify converts its arguments to a string and the type of the content. +// All pointers are dereferenced, as in the text/template package. +func stringify(args ...interface{}) (string, contentType) { + if len(args) == 1 { + switch s := indirect(args[0]).(type) { + case string: + return s, contentTypePlain + case CSS: + return string(s), contentTypeCSS + case HTML: + return string(s), contentTypeHTML + case HTMLAttr: + return string(s), contentTypeHTMLAttr + case JS: + return string(s), contentTypeJS + case JSStr: + return string(s), contentTypeJSStr + case URL: + return string(s), contentTypeURL + case Srcset: + return string(s), contentTypeSrcset + } + } + i := 0 + for _, arg := range args { + // We skip untyped nil arguments for backward compatibility. + // Without this they would be output as <nil>, escaped. + // See issue 25875. + if arg == nil { + continue + } + + args[i] = indirectToStringerOrError(arg) + i++ + } + return fmt.Sprint(args[:i]...), contentTypePlain +} diff --git a/src/html/template/content_test.go b/src/html/template/content_test.go new file mode 100644 index 0000000..b7a39d4 --- /dev/null +++ b/src/html/template/content_test.go @@ -0,0 +1,458 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package template + +import ( + "bytes" + "fmt" + "strings" + "testing" +) + +func TestTypedContent(t *testing.T) { + data := []interface{}{ + `<b> "foo%" O'Reilly &bar;`, + CSS(`a[href =~ "//example.com"]#foo`), + HTML(`Hello, <b>World</b> &tc!`), + HTMLAttr(` dir="ltr"`), + JS(`c && alert("Hello, World!");`), + JSStr(`Hello, World & O'Reilly\u0021`), + URL(`greeting=H%69,&addressee=(World)`), + Srcset(`greeting=H%69,&addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`), + URL(`,foo/,`), + } + + // For each content sensitive escaper, see how it does on + // each of the typed strings above. + tests := []struct { + // A template containing a single {{.}}. + input string + want []string + }{ + { + `<style>{{.}} { color: blue }</style>`, + []string{ + `ZgotmplZ`, + // Allowed but not escaped. + `a[href =~ "//example.com"]#foo`, + `ZgotmplZ`, + `ZgotmplZ`, + `ZgotmplZ`, + `ZgotmplZ`, + `ZgotmplZ`, + `ZgotmplZ`, + `ZgotmplZ`, + }, + }, + { + `<div style="{{.}}">`, + []string{ + `ZgotmplZ`, + // Allowed and HTML escaped. + `a[href =~ "//example.com"]#foo`, + `ZgotmplZ`, + `ZgotmplZ`, + `ZgotmplZ`, + `ZgotmplZ`, + `ZgotmplZ`, + `ZgotmplZ`, + `ZgotmplZ`, + }, + }, + { + `{{.}}`, + []string{ + `<b> "foo%" O'Reilly &bar;`, + `a[href =~ "//example.com"]#foo`, + // Not escaped. + `Hello, <b>World</b> &tc!`, + ` dir="ltr"`, + `c && alert("Hello, World!");`, + `Hello, World & O'Reilly\u0021`, + `greeting=H%69,&addressee=(World)`, + `greeting=H%69,&addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`, + `,foo/,`, + }, + }, + { + `<a{{.}}>`, + []string{ + `ZgotmplZ`, + `ZgotmplZ`, + `ZgotmplZ`, + // Allowed and HTML escaped. + ` dir="ltr"`, + `ZgotmplZ`, + `ZgotmplZ`, + `ZgotmplZ`, + `ZgotmplZ`, + `ZgotmplZ`, + }, + }, + { + `<a title={{.}}>`, + []string{ + `<b> "foo%" O'Reilly &bar;`, + `a[href =~ "//example.com"]#foo`, + // Tags stripped, spaces escaped, entity not re-escaped. + `Hello, World &tc!`, + ` dir="ltr"`, + `c && alert("Hello, World!");`, + `Hello, World & O'Reilly\u0021`, + `greeting=H%69,&addressee=(World)`, + `greeting=H%69,&addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`, + `,foo/,`, + }, + }, + { + `<a title='{{.}}'>`, + []string{ + `<b> "foo%" O'Reilly &bar;`, + `a[href =~ "//example.com"]#foo`, + // Tags stripped, entity not re-escaped. + `Hello, World &tc!`, + ` dir="ltr"`, + `c && alert("Hello, World!");`, + `Hello, World & O'Reilly\u0021`, + `greeting=H%69,&addressee=(World)`, + `greeting=H%69,&addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`, + `,foo/,`, + }, + }, + { + `<textarea>{{.}}</textarea>`, + []string{ + `<b> "foo%" O'Reilly &bar;`, + `a[href =~ "//example.com"]#foo`, + // Angle brackets escaped to prevent injection of close tags, entity not re-escaped. + `Hello, <b>World</b> &tc!`, + ` dir="ltr"`, + `c && alert("Hello, World!");`, + `Hello, World & O'Reilly\u0021`, + `greeting=H%69,&addressee=(World)`, + `greeting=H%69,&addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`, + `,foo/,`, + }, + }, + { + `<script>alert({{.}})</script>`, + []string{ + `"\u003cb\u003e \"foo%\" O'Reilly \u0026bar;"`, + `"a[href =~ \"//example.com\"]#foo"`, + `"Hello, \u003cb\u003eWorld\u003c/b\u003e \u0026amp;tc!"`, + `" dir=\"ltr\""`, + // Not escaped. + `c && alert("Hello, World!");`, + // Escape sequence not over-escaped. + `"Hello, World & O'Reilly\u0021"`, + `"greeting=H%69,\u0026addressee=(World)"`, + `"greeting=H%69,\u0026addressee=(World) 2x, https://golang.org/favicon.ico 500.5w"`, + `",foo/,"`, + }, + }, + { + `<button onclick="alert({{.}})">`, + []string{ + `"\u003cb\u003e \"foo%\" O'Reilly \u0026bar;"`, + `"a[href =~ \"//example.com\"]#foo"`, + `"Hello, \u003cb\u003eWorld\u003c/b\u003e \u0026amp;tc!"`, + `" dir=\"ltr\""`, + // Not JS escaped but HTML escaped. + `c && alert("Hello, World!");`, + // Escape sequence not over-escaped. + `"Hello, World & O'Reilly\u0021"`, + `"greeting=H%69,\u0026addressee=(World)"`, + `"greeting=H%69,\u0026addressee=(World) 2x, https://golang.org/favicon.ico 500.5w"`, + `",foo/,"`, + }, + }, + { + `<script>alert("{{.}}")</script>`, + []string{ + `\u003cb\u003e \u0022foo%\u0022 O\u0027Reilly \u0026bar;`, + `a[href =~ \u0022\/\/example.com\u0022]#foo`, + `Hello, \u003cb\u003eWorld\u003c\/b\u003e \u0026amp;tc!`, + ` dir=\u0022ltr\u0022`, + `c \u0026\u0026 alert(\u0022Hello, World!\u0022);`, + // Escape sequence not over-escaped. + `Hello, World \u0026 O\u0027Reilly\u0021`, + `greeting=H%69,\u0026addressee=(World)`, + `greeting=H%69,\u0026addressee=(World) 2x, https:\/\/golang.org\/favicon.ico 500.5w`, + `,foo\/,`, + }, + }, + { + `<script type="text/javascript">alert("{{.}}")</script>`, + []string{ + `\u003cb\u003e \u0022foo%\u0022 O\u0027Reilly \u0026bar;`, + `a[href =~ \u0022\/\/example.com\u0022]#foo`, + `Hello, \u003cb\u003eWorld\u003c\/b\u003e \u0026amp;tc!`, + ` dir=\u0022ltr\u0022`, + `c \u0026\u0026 alert(\u0022Hello, World!\u0022);`, + // Escape sequence not over-escaped. + `Hello, World \u0026 O\u0027Reilly\u0021`, + `greeting=H%69,\u0026addressee=(World)`, + `greeting=H%69,\u0026addressee=(World) 2x, https:\/\/golang.org\/favicon.ico 500.5w`, + `,foo\/,`, + }, + }, + { + `<script type="text/javascript">alert({{.}})</script>`, + []string{ + `"\u003cb\u003e \"foo%\" O'Reilly \u0026bar;"`, + `"a[href =~ \"//example.com\"]#foo"`, + `"Hello, \u003cb\u003eWorld\u003c/b\u003e \u0026amp;tc!"`, + `" dir=\"ltr\""`, + // Not escaped. + `c && alert("Hello, World!");`, + // Escape sequence not over-escaped. + `"Hello, World & O'Reilly\u0021"`, + `"greeting=H%69,\u0026addressee=(World)"`, + `"greeting=H%69,\u0026addressee=(World) 2x, https://golang.org/favicon.ico 500.5w"`, + `",foo/,"`, + }, + }, + { + // Not treated as JS. The output is same as for <div>{{.}}</div> + `<script type="text/template">{{.}}</script>`, + []string{ + `<b> "foo%" O'Reilly &bar;`, + `a[href =~ "//example.com"]#foo`, + // Not escaped. + `Hello, <b>World</b> &tc!`, + ` dir="ltr"`, + `c && alert("Hello, World!");`, + `Hello, World & O'Reilly\u0021`, + `greeting=H%69,&addressee=(World)`, + `greeting=H%69,&addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`, + `,foo/,`, + }, + }, + { + `<button onclick='alert("{{.}}")'>`, + []string{ + `\u003cb\u003e \u0022foo%\u0022 O\u0027Reilly \u0026bar;`, + `a[href =~ \u0022\/\/example.com\u0022]#foo`, + `Hello, \u003cb\u003eWorld\u003c\/b\u003e \u0026amp;tc!`, + ` dir=\u0022ltr\u0022`, + `c \u0026\u0026 alert(\u0022Hello, World!\u0022);`, + // Escape sequence not over-escaped. + `Hello, World \u0026 O\u0027Reilly\u0021`, + `greeting=H%69,\u0026addressee=(World)`, + `greeting=H%69,\u0026addressee=(World) 2x, https:\/\/golang.org\/favicon.ico 500.5w`, + `,foo\/,`, + }, + }, + { + `<a href="?q={{.}}">`, + []string{ + `%3cb%3e%20%22foo%25%22%20O%27Reilly%20%26bar%3b`, + `a%5bhref%20%3d~%20%22%2f%2fexample.com%22%5d%23foo`, + `Hello%2c%20%3cb%3eWorld%3c%2fb%3e%20%26amp%3btc%21`, + `%20dir%3d%22ltr%22`, + `c%20%26%26%20alert%28%22Hello%2c%20World%21%22%29%3b`, + `Hello%2c%20World%20%26%20O%27Reilly%5cu0021`, + // Quotes and parens are escaped but %69 is not over-escaped. HTML escaping is done. + `greeting=H%69,&addressee=%28World%29`, + `greeting%3dH%2569%2c%26addressee%3d%28World%29%202x%2c%20https%3a%2f%2fgolang.org%2ffavicon.ico%20500.5w`, + `,foo/,`, + }, + }, + { + `<style>body { background: url('?img={{.}}') }</style>`, + []string{ + `%3cb%3e%20%22foo%25%22%20O%27Reilly%20%26bar%3b`, + `a%5bhref%20%3d~%20%22%2f%2fexample.com%22%5d%23foo`, + `Hello%2c%20%3cb%3eWorld%3c%2fb%3e%20%26amp%3btc%21`, + `%20dir%3d%22ltr%22`, + `c%20%26%26%20alert%28%22Hello%2c%20World%21%22%29%3b`, + `Hello%2c%20World%20%26%20O%27Reilly%5cu0021`, + // Quotes and parens are escaped but %69 is not over-escaped. HTML escaping is not done. + `greeting=H%69,&addressee=%28World%29`, + `greeting%3dH%2569%2c%26addressee%3d%28World%29%202x%2c%20https%3a%2f%2fgolang.org%2ffavicon.ico%20500.5w`, + `,foo/,`, + }, + }, + { + `<img srcset="{{.}}">`, + []string{ + `#ZgotmplZ`, + `#ZgotmplZ`, + // Commas are not esacped + `Hello,#ZgotmplZ`, + // Leading spaces are not percent escapes. + ` dir=%22ltr%22`, + // Spaces after commas are not percent escaped. + `#ZgotmplZ, World!%22%29;`, + `Hello,#ZgotmplZ`, + `greeting=H%69%2c&addressee=%28World%29`, + // Metadata is not escaped. + `greeting=H%69,&addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`, + `%2cfoo/%2c`, + }, + }, + { + `<img srcset={{.}}>`, + []string{ + `#ZgotmplZ`, + `#ZgotmplZ`, + `Hello,#ZgotmplZ`, + // Spaces are HTML escaped not %-escaped + ` dir=%22ltr%22`, + `#ZgotmplZ, World!%22%29;`, + `Hello,#ZgotmplZ`, + `greeting=H%69%2c&addressee=%28World%29`, + `greeting=H%69,&addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`, + // Commas are escaped. + `%2cfoo/%2c`, + }, + }, + { + `<img srcset="{{.}} 2x, https://golang.org/ 500.5w">`, + []string{ + `#ZgotmplZ`, + `#ZgotmplZ`, + `Hello,#ZgotmplZ`, + ` dir=%22ltr%22`, + `#ZgotmplZ, World!%22%29;`, + `Hello,#ZgotmplZ`, + `greeting=H%69%2c&addressee=%28World%29`, + `greeting=H%69,&addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`, + `%2cfoo/%2c`, + }, + }, + { + `<img srcset="http://godoc.org/ {{.}}, https://golang.org/ 500.5w">`, + []string{ + `#ZgotmplZ`, + `#ZgotmplZ`, + `Hello,#ZgotmplZ`, + ` dir=%22ltr%22`, + `#ZgotmplZ, World!%22%29;`, + `Hello,#ZgotmplZ`, + `greeting=H%69%2c&addressee=%28World%29`, + `greeting=H%69,&addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`, + `%2cfoo/%2c`, + }, + }, + { + `<img srcset="http://godoc.org/?q={{.}} 2x, https://golang.org/ 500.5w">`, + []string{ + `#ZgotmplZ`, + `#ZgotmplZ`, + `Hello,#ZgotmplZ`, + ` dir=%22ltr%22`, + `#ZgotmplZ, World!%22%29;`, + `Hello,#ZgotmplZ`, + `greeting=H%69%2c&addressee=%28World%29`, + `greeting=H%69,&addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`, + `%2cfoo/%2c`, + }, + }, + { + `<img srcset="http://godoc.org/ 2x, {{.}} 500.5w">`, + []string{ + `#ZgotmplZ`, + `#ZgotmplZ`, + `Hello,#ZgotmplZ`, + ` dir=%22ltr%22`, + `#ZgotmplZ, World!%22%29;`, + `Hello,#ZgotmplZ`, + `greeting=H%69%2c&addressee=%28World%29`, + `greeting=H%69,&addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`, + `%2cfoo/%2c`, + }, + }, + { + `<img srcset="http://godoc.org/ 2x, https://golang.org/ {{.}}">`, + []string{ + `#ZgotmplZ`, + `#ZgotmplZ`, + `Hello,#ZgotmplZ`, + ` dir=%22ltr%22`, + `#ZgotmplZ, World!%22%29;`, + `Hello,#ZgotmplZ`, + `greeting=H%69%2c&addressee=%28World%29`, + `greeting=H%69,&addressee=(World) 2x, https://golang.org/favicon.ico 500.5w`, + `%2cfoo/%2c`, + }, + }, + } + + for _, test := range tests { + tmpl := Must(New("x").Parse(test.input)) + pre := strings.Index(test.input, "{{.}}") + post := len(test.input) - (pre + 5) + var b bytes.Buffer + for i, x := range data { + b.Reset() + if err := tmpl.Execute(&b, x); err != nil { + t.Errorf("%q with %v: %s", test.input, x, err) + continue + } + if want, got := test.want[i], b.String()[pre:b.Len()-post]; want != got { + t.Errorf("%q with %v:\nwant\n\t%q,\ngot\n\t%q\n", test.input, x, want, got) + continue + } + } + } +} + +// Test that we print using the String method. Was issue 3073. +type myStringer struct { + v int +} + +func (s *myStringer) String() string { + return fmt.Sprintf("string=%d", s.v) +} + +type errorer struct { + v int +} + +func (s *errorer) Error() string { + return fmt.Sprintf("error=%d", s.v) +} + +func TestStringer(t *testing.T) { + s := &myStringer{3} + b := new(bytes.Buffer) + tmpl := Must(New("x").Parse("{{.}}")) + if err := tmpl.Execute(b, s); err != nil { + t.Fatal(err) + } + var expect = "string=3" + if b.String() != expect { + t.Errorf("expected %q got %q", expect, b.String()) + } + e := &errorer{7} + b.Reset() + if err := tmpl.Execute(b, e); err != nil { + t.Fatal(err) + } + expect = "error=7" + if b.String() != expect { + t.Errorf("expected %q got %q", expect, b.String()) + } +} + +// https://golang.org/issue/5982 +func TestEscapingNilNonemptyInterfaces(t *testing.T) { + tmpl := Must(New("x").Parse("{{.E}}")) + + got := new(bytes.Buffer) + testData := struct{ E error }{} // any non-empty interface here will do; error is just ready at hand + tmpl.Execute(got, testData) + + // A non-empty interface should print like an empty interface. + want := new(bytes.Buffer) + data := struct{ E interface{} }{} + tmpl.Execute(want, data) + + if !bytes.Equal(want.Bytes(), got.Bytes()) { + t.Errorf("expected %q got %q", string(want.Bytes()), string(got.Bytes())) + } +} diff --git a/src/html/template/context.go b/src/html/template/context.go new file mode 100644 index 0000000..f7d4849 --- /dev/null +++ b/src/html/template/context.go @@ -0,0 +1,260 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package template + +import ( + "fmt" +) + +// context describes the state an HTML parser must be in when it reaches the +// portion of HTML produced by evaluating a particular template node. +// +// The zero value of type context is the start context for a template that +// produces an HTML fragment as defined at +// https://www.w3.org/TR/html5/syntax.html#the-end +// where the context element is null. +type context struct { + state state + delim delim + urlPart urlPart + jsCtx jsCtx + attr attr + element element + err *Error +} + +func (c context) String() string { + var err error + if c.err != nil { + err = c.err + } + return fmt.Sprintf("{%v %v %v %v %v %v %v}", c.state, c.delim, c.urlPart, c.jsCtx, c.attr, c.element, err) +} + +// eq reports whether two contexts are equal. +func (c context) eq(d context) bool { + return c.state == d.state && + c.delim == d.delim && + c.urlPart == d.urlPart && + c.jsCtx == d.jsCtx && + c.attr == d.attr && + c.element == d.element && + c.err == d.err +} + +// mangle produces an identifier that includes a suffix that distinguishes it +// from template names mangled with different contexts. +func (c context) mangle(templateName string) string { + // The mangled name for the default context is the input templateName. + if c.state == stateText { + return templateName + } + s := templateName + "$htmltemplate_" + c.state.String() + if c.delim != delimNone { + s += "_" + c.delim.String() + } + if c.urlPart != urlPartNone { + s += "_" + c.urlPart.String() + } + if c.jsCtx != jsCtxRegexp { + s += "_" + c.jsCtx.String() + } + if c.attr != attrNone { + s += "_" + c.attr.String() + } + if c.element != elementNone { + s += "_" + c.element.String() + } + return s +} + +// state describes a high-level HTML parser state. +// +// It bounds the top of the element stack, and by extension the HTML insertion +// mode, but also contains state that does not correspond to anything in the +// HTML5 parsing algorithm because a single token production in the HTML +// grammar may contain embedded actions in a template. For instance, the quoted +// HTML attribute produced by +// <div title="Hello {{.World}}"> +// is a single token in HTML's grammar but in a template spans several nodes. +type state uint8 + +//go:generate stringer -type state + +const ( + // stateText is parsed character data. An HTML parser is in + // this state when its parse position is outside an HTML tag, + // directive, comment, and special element body. + stateText state = iota + // stateTag occurs before an HTML attribute or the end of a tag. + stateTag + // stateAttrName occurs inside an attribute name. + // It occurs between the ^'s in ` ^name^ = value`. + stateAttrName + // stateAfterName occurs after an attr name has ended but before any + // equals sign. It occurs between the ^'s in ` name^ ^= value`. + stateAfterName + // stateBeforeValue occurs after the equals sign but before the value. + // It occurs between the ^'s in ` name =^ ^value`. + stateBeforeValue + // stateHTMLCmt occurs inside an <!-- HTML comment -->. + stateHTMLCmt + // stateRCDATA occurs inside an RCDATA element (<textarea> or <title>) + // as described at https://www.w3.org/TR/html5/syntax.html#elements-0 + stateRCDATA + // stateAttr occurs inside an HTML attribute whose content is text. + stateAttr + // stateURL occurs inside an HTML attribute whose content is a URL. + stateURL + // stateSrcset occurs inside an HTML srcset attribute. + stateSrcset + // stateJS occurs inside an event handler or script element. + stateJS + // stateJSDqStr occurs inside a JavaScript double quoted string. + stateJSDqStr + // stateJSSqStr occurs inside a JavaScript single quoted string. + stateJSSqStr + // stateJSRegexp occurs inside a JavaScript regexp literal. + stateJSRegexp + // stateJSBlockCmt occurs inside a JavaScript /* block comment */. + stateJSBlockCmt + // stateJSLineCmt occurs inside a JavaScript // line comment. + stateJSLineCmt + // stateCSS occurs inside a <style> element or style attribute. + stateCSS + // stateCSSDqStr occurs inside a CSS double quoted string. + stateCSSDqStr + // stateCSSSqStr occurs inside a CSS single quoted string. + stateCSSSqStr + // stateCSSDqURL occurs inside a CSS double quoted url("..."). + stateCSSDqURL + // stateCSSSqURL occurs inside a CSS single quoted url('...'). + stateCSSSqURL + // stateCSSURL occurs inside a CSS unquoted url(...). + stateCSSURL + // stateCSSBlockCmt occurs inside a CSS /* block comment */. + stateCSSBlockCmt + // stateCSSLineCmt occurs inside a CSS // line comment. + stateCSSLineCmt + // stateError is an infectious error state outside any valid + // HTML/CSS/JS construct. + stateError +) + +// isComment is true for any state that contains content meant for template +// authors & maintainers, not for end-users or machines. +func isComment(s state) bool { + switch s { + case stateHTMLCmt, stateJSBlockCmt, stateJSLineCmt, stateCSSBlockCmt, stateCSSLineCmt: + return true + } + return false +} + +// isInTag return whether s occurs solely inside an HTML tag. +func isInTag(s state) bool { + switch s { + case stateTag, stateAttrName, stateAfterName, stateBeforeValue, stateAttr: + return true + } + return false +} + +// delim is the delimiter that will end the current HTML attribute. +type delim uint8 + +//go:generate stringer -type delim + +const ( + // delimNone occurs outside any attribute. + delimNone delim = iota + // delimDoubleQuote occurs when a double quote (") closes the attribute. + delimDoubleQuote + // delimSingleQuote occurs when a single quote (') closes the attribute. + delimSingleQuote + // delimSpaceOrTagEnd occurs when a space or right angle bracket (>) + // closes the attribute. + delimSpaceOrTagEnd +) + +// urlPart identifies a part in an RFC 3986 hierarchical URL to allow different +// encoding strategies. +type urlPart uint8 + +//go:generate stringer -type urlPart + +const ( + // urlPartNone occurs when not in a URL, or possibly at the start: + // ^ in "^http://auth/path?k=v#frag". + urlPartNone urlPart = iota + // urlPartPreQuery occurs in the scheme, authority, or path; between the + // ^s in "h^ttp://auth/path^?k=v#frag". + urlPartPreQuery + // urlPartQueryOrFrag occurs in the query portion between the ^s in + // "http://auth/path?^k=v#frag^". + urlPartQueryOrFrag + // urlPartUnknown occurs due to joining of contexts both before and + // after the query separator. + urlPartUnknown +) + +// jsCtx determines whether a '/' starts a regular expression literal or a +// division operator. +type jsCtx uint8 + +//go:generate stringer -type jsCtx + +const ( + // jsCtxRegexp occurs where a '/' would start a regexp literal. + jsCtxRegexp jsCtx = iota + // jsCtxDivOp occurs where a '/' would start a division operator. + jsCtxDivOp + // jsCtxUnknown occurs where a '/' is ambiguous due to context joining. + jsCtxUnknown +) + +// element identifies the HTML element when inside a start tag or special body. +// Certain HTML element (for example <script> and <style>) have bodies that are +// treated differently from stateText so the element type is necessary to +// transition into the correct context at the end of a tag and to identify the +// end delimiter for the body. +type element uint8 + +//go:generate stringer -type element + +const ( + // elementNone occurs outside a special tag or special element body. + elementNone element = iota + // elementScript corresponds to the raw text <script> element + // with JS MIME type or no type attribute. + elementScript + // elementStyle corresponds to the raw text <style> element. + elementStyle + // elementTextarea corresponds to the RCDATA <textarea> element. + elementTextarea + // elementTitle corresponds to the RCDATA <title> element. + elementTitle +) + +//go:generate stringer -type attr + +// attr identifies the current HTML attribute when inside the attribute, +// that is, starting from stateAttrName until stateTag/stateText (exclusive). +type attr uint8 + +const ( + // attrNone corresponds to a normal attribute or no attribute. + attrNone attr = iota + // attrScript corresponds to an event handler attribute. + attrScript + // attrScriptType corresponds to the type attribute in script HTML element + attrScriptType + // attrStyle corresponds to the style attribute whose value is CSS. + attrStyle + // attrURL corresponds to an attribute whose value is a URL. + attrURL + // attrSrcset corresponds to a srcset attribute. + attrSrcset +) diff --git a/src/html/template/css.go b/src/html/template/css.go new file mode 100644 index 0000000..eb92fc9 --- /dev/null +++ b/src/html/template/css.go @@ -0,0 +1,260 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package template + +import ( + "bytes" + "fmt" + "strings" + "unicode" + "unicode/utf8" +) + +// endsWithCSSKeyword reports whether b ends with an ident that +// case-insensitively matches the lower-case kw. +func endsWithCSSKeyword(b []byte, kw string) bool { + i := len(b) - len(kw) + if i < 0 { + // Too short. + return false + } + if i != 0 { + r, _ := utf8.DecodeLastRune(b[:i]) + if isCSSNmchar(r) { + // Too long. + return false + } + } + // Many CSS keywords, such as "!important" can have characters encoded, + // but the URI production does not allow that according to + // https://www.w3.org/TR/css3-syntax/#TOK-URI + // This does not attempt to recognize encoded keywords. For example, + // given "\75\72\6c" and "url" this return false. + return string(bytes.ToLower(b[i:])) == kw +} + +// isCSSNmchar reports whether rune is allowed anywhere in a CSS identifier. +func isCSSNmchar(r rune) bool { + // Based on the CSS3 nmchar production but ignores multi-rune escape + // sequences. + // https://www.w3.org/TR/css3-syntax/#SUBTOK-nmchar + return 'a' <= r && r <= 'z' || + 'A' <= r && r <= 'Z' || + '0' <= r && r <= '9' || + r == '-' || + r == '_' || + // Non-ASCII cases below. + 0x80 <= r && r <= 0xd7ff || + 0xe000 <= r && r <= 0xfffd || + 0x10000 <= r && r <= 0x10ffff +} + +// decodeCSS decodes CSS3 escapes given a sequence of stringchars. +// If there is no change, it returns the input, otherwise it returns a slice +// backed by a new array. +// https://www.w3.org/TR/css3-syntax/#SUBTOK-stringchar defines stringchar. +func decodeCSS(s []byte) []byte { + i := bytes.IndexByte(s, '\\') + if i == -1 { + return s + } + // The UTF-8 sequence for a codepoint is never longer than 1 + the + // number hex digits need to represent that codepoint, so len(s) is an + // upper bound on the output length. + b := make([]byte, 0, len(s)) + for len(s) != 0 { + i := bytes.IndexByte(s, '\\') + if i == -1 { + i = len(s) + } + b, s = append(b, s[:i]...), s[i:] + if len(s) < 2 { + break + } + // https://www.w3.org/TR/css3-syntax/#SUBTOK-escape + // escape ::= unicode | '\' [#x20-#x7E#x80-#xD7FF#xE000-#xFFFD#x10000-#x10FFFF] + if isHex(s[1]) { + // https://www.w3.org/TR/css3-syntax/#SUBTOK-unicode + // unicode ::= '\' [0-9a-fA-F]{1,6} wc? + j := 2 + for j < len(s) && j < 7 && isHex(s[j]) { + j++ + } + r := hexDecode(s[1:j]) + if r > unicode.MaxRune { + r, j = r/16, j-1 + } + n := utf8.EncodeRune(b[len(b):cap(b)], r) + // The optional space at the end allows a hex + // sequence to be followed by a literal hex. + // string(decodeCSS([]byte(`\A B`))) == "\nB" + b, s = b[:len(b)+n], skipCSSSpace(s[j:]) + } else { + // `\\` decodes to `\` and `\"` to `"`. + _, n := utf8.DecodeRune(s[1:]) + b, s = append(b, s[1:1+n]...), s[1+n:] + } + } + return b +} + +// isHex reports whether the given character is a hex digit. +func isHex(c byte) bool { + return '0' <= c && c <= '9' || 'a' <= c && c <= 'f' || 'A' <= c && c <= 'F' +} + +// hexDecode decodes a short hex digit sequence: "10" -> 16. +func hexDecode(s []byte) rune { + n := '\x00' + for _, c := range s { + n <<= 4 + switch { + case '0' <= c && c <= '9': + n |= rune(c - '0') + case 'a' <= c && c <= 'f': + n |= rune(c-'a') + 10 + case 'A' <= c && c <= 'F': + n |= rune(c-'A') + 10 + default: + panic(fmt.Sprintf("Bad hex digit in %q", s)) + } + } + return n +} + +// skipCSSSpace returns a suffix of c, skipping over a single space. +func skipCSSSpace(c []byte) []byte { + if len(c) == 0 { + return c + } + // wc ::= #x9 | #xA | #xC | #xD | #x20 + switch c[0] { + case '\t', '\n', '\f', ' ': + return c[1:] + case '\r': + // This differs from CSS3's wc production because it contains a + // probable spec error whereby wc contains all the single byte + // sequences in nl (newline) but not CRLF. + if len(c) >= 2 && c[1] == '\n' { + return c[2:] + } + return c[1:] + } + return c +} + +// isCSSSpace reports whether b is a CSS space char as defined in wc. +func isCSSSpace(b byte) bool { + switch b { + case '\t', '\n', '\f', '\r', ' ': + return true + } + return false +} + +// cssEscaper escapes HTML and CSS special characters using \<hex>+ escapes. +func cssEscaper(args ...interface{}) string { + s, _ := stringify(args...) + var b strings.Builder + r, w, written := rune(0), 0, 0 + for i := 0; i < len(s); i += w { + // See comment in htmlEscaper. + r, w = utf8.DecodeRuneInString(s[i:]) + var repl string + switch { + case int(r) < len(cssReplacementTable) && cssReplacementTable[r] != "": + repl = cssReplacementTable[r] + default: + continue + } + if written == 0 { + b.Grow(len(s)) + } + b.WriteString(s[written:i]) + b.WriteString(repl) + written = i + w + if repl != `\\` && (written == len(s) || isHex(s[written]) || isCSSSpace(s[written])) { + b.WriteByte(' ') + } + } + if written == 0 { + return s + } + b.WriteString(s[written:]) + return b.String() +} + +var cssReplacementTable = []string{ + 0: `\0`, + '\t': `\9`, + '\n': `\a`, + '\f': `\c`, + '\r': `\d`, + // Encode HTML specials as hex so the output can be embedded + // in HTML attributes without further encoding. + '"': `\22`, + '&': `\26`, + '\'': `\27`, + '(': `\28`, + ')': `\29`, + '+': `\2b`, + '/': `\2f`, + ':': `\3a`, + ';': `\3b`, + '<': `\3c`, + '>': `\3e`, + '\\': `\\`, + '{': `\7b`, + '}': `\7d`, +} + +var expressionBytes = []byte("expression") +var mozBindingBytes = []byte("mozbinding") + +// cssValueFilter allows innocuous CSS values in the output including CSS +// quantities (10px or 25%), ID or class literals (#foo, .bar), keyword values +// (inherit, blue), and colors (#888). +// It filters out unsafe values, such as those that affect token boundaries, +// and anything that might execute scripts. +func cssValueFilter(args ...interface{}) string { + s, t := stringify(args...) + if t == contentTypeCSS { + return s + } + b, id := decodeCSS([]byte(s)), make([]byte, 0, 64) + + // CSS3 error handling is specified as honoring string boundaries per + // https://www.w3.org/TR/css3-syntax/#error-handling : + // Malformed declarations. User agents must handle unexpected + // tokens encountered while parsing a declaration by reading until + // the end of the declaration, while observing the rules for + // matching pairs of (), [], {}, "", and '', and correctly handling + // escapes. For example, a malformed declaration may be missing a + // property, colon (:) or value. + // So we need to make sure that values do not have mismatched bracket + // or quote characters to prevent the browser from restarting parsing + // inside a string that might embed JavaScript source. + for i, c := range b { + switch c { + case 0, '"', '\'', '(', ')', '/', ';', '@', '[', '\\', ']', '`', '{', '}': + return filterFailsafe + case '-': + // Disallow <!-- or -->. + // -- should not appear in valid identifiers. + if i != 0 && b[i-1] == '-' { + return filterFailsafe + } + default: + if c < utf8.RuneSelf && isCSSNmchar(rune(c)) { + id = append(id, c) + } + } + } + id = bytes.ToLower(id) + if bytes.Contains(id, expressionBytes) || bytes.Contains(id, mozBindingBytes) { + return filterFailsafe + } + return string(b) +} diff --git a/src/html/template/css_test.go b/src/html/template/css_test.go new file mode 100644 index 0000000..a735638 --- /dev/null +++ b/src/html/template/css_test.go @@ -0,0 +1,281 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package template + +import ( + "strconv" + "strings" + "testing" +) + +func TestEndsWithCSSKeyword(t *testing.T) { + tests := []struct { + css, kw string + want bool + }{ + {"", "url", false}, + {"url", "url", true}, + {"URL", "url", true}, + {"Url", "url", true}, + {"url", "important", false}, + {"important", "important", true}, + {"image-url", "url", false}, + {"imageurl", "url", false}, + {"image url", "url", true}, + } + for _, test := range tests { + got := endsWithCSSKeyword([]byte(test.css), test.kw) + if got != test.want { + t.Errorf("want %t but got %t for css=%v, kw=%v", test.want, got, test.css, test.kw) + } + } +} + +func TestIsCSSNmchar(t *testing.T) { + tests := []struct { + rune rune + want bool + }{ + {0, false}, + {'0', true}, + {'9', true}, + {'A', true}, + {'Z', true}, + {'a', true}, + {'z', true}, + {'_', true}, + {'-', true}, + {':', false}, + {';', false}, + {' ', false}, + {0x7f, false}, + {0x80, true}, + {0x1234, true}, + {0xd800, false}, + {0xdc00, false}, + {0xfffe, false}, + {0x10000, true}, + {0x110000, false}, + } + for _, test := range tests { + got := isCSSNmchar(test.rune) + if got != test.want { + t.Errorf("%q: want %t but got %t", string(test.rune), test.want, got) + } + } +} + +func TestDecodeCSS(t *testing.T) { + tests := []struct { + css, want string + }{ + {``, ``}, + {`foo`, `foo`}, + {`foo\`, `foo`}, + {`foo\\`, `foo\`}, + {`\`, ``}, + {`\A`, "\n"}, + {`\a`, "\n"}, + {`\0a`, "\n"}, + {`\00000a`, "\n"}, + {`\000000a`, "\u0000a"}, + {`\1234 5`, "\u1234" + "5"}, + {`\1234\20 5`, "\u1234" + " 5"}, + {`\1234\A 5`, "\u1234" + "\n5"}, + {"\\1234\t5", "\u1234" + "5"}, + {"\\1234\n5", "\u1234" + "5"}, + {"\\1234\r\n5", "\u1234" + "5"}, + {`\12345`, "\U00012345"}, + {`\\`, `\`}, + {`\\ `, `\ `}, + {`\"`, `"`}, + {`\'`, `'`}, + {`\.`, `.`}, + {`\. .`, `. .`}, + { + `The \3c i\3equick\3c/i\3e,\d\A\3cspan style=\27 color:brown\27\3e brown\3c/span\3e fox jumps\2028over the \3c canine class=\22lazy\22 \3e dog\3c/canine\3e`, + "The <i>quick</i>,\r\n<span style='color:brown'>brown</span> fox jumps\u2028over the <canine class=\"lazy\">dog</canine>", + }, + } + for _, test := range tests { + got1 := string(decodeCSS([]byte(test.css))) + if got1 != test.want { + t.Errorf("%q: want\n\t%q\nbut got\n\t%q", test.css, test.want, got1) + } + recoded := cssEscaper(got1) + if got2 := string(decodeCSS([]byte(recoded))); got2 != test.want { + t.Errorf("%q: escape & decode not dual for %q", test.css, recoded) + } + } +} + +func TestHexDecode(t *testing.T) { + for i := 0; i < 0x200000; i += 101 /* coprime with 16 */ { + s := strconv.FormatInt(int64(i), 16) + if got := int(hexDecode([]byte(s))); got != i { + t.Errorf("%s: want %d but got %d", s, i, got) + } + s = strings.ToUpper(s) + if got := int(hexDecode([]byte(s))); got != i { + t.Errorf("%s: want %d but got %d", s, i, got) + } + } +} + +func TestSkipCSSSpace(t *testing.T) { + tests := []struct { + css, want string + }{ + {"", ""}, + {"foo", "foo"}, + {"\n", ""}, + {"\r\n", ""}, + {"\r", ""}, + {"\t", ""}, + {" ", ""}, + {"\f", ""}, + {" foo", "foo"}, + {" foo", " foo"}, + {`\20`, `\20`}, + } + for _, test := range tests { + got := string(skipCSSSpace([]byte(test.css))) + if got != test.want { + t.Errorf("%q: want %q but got %q", test.css, test.want, got) + } + } +} + +func TestCSSEscaper(t *testing.T) { + input := ("\x00\x01\x02\x03\x04\x05\x06\x07\x08\t\n\x0b\x0c\r\x0e\x0f" + + "\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f" + + ` !"#$%&'()*+,-./` + + `0123456789:;<=>?` + + `@ABCDEFGHIJKLMNO` + + `PQRSTUVWXYZ[\]^_` + + "`abcdefghijklmno" + + "pqrstuvwxyz{|}~\x7f" + + "\u00A0\u0100\u2028\u2029\ufeff\U0001D11E") + + want := ("\\0\x01\x02\x03\x04\x05\x06\x07" + + "\x08\\9 \\a\x0b\\c \\d\x0E\x0F" + + "\x10\x11\x12\x13\x14\x15\x16\x17" + + "\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f" + + ` !\22#$%\26\27\28\29*\2b,-.\2f ` + + `0123456789\3a\3b\3c=\3e?` + + `@ABCDEFGHIJKLMNO` + + `PQRSTUVWXYZ[\\]^_` + + "`abcdefghijklmno" + + `pqrstuvwxyz\7b|\7d~` + "\u007f" + + "\u00A0\u0100\u2028\u2029\ufeff\U0001D11E") + + got := cssEscaper(input) + if got != want { + t.Errorf("encode: want\n\t%q\nbut got\n\t%q", want, got) + } + + got = string(decodeCSS([]byte(got))) + if input != got { + t.Errorf("decode: want\n\t%q\nbut got\n\t%q", input, got) + } +} + +func TestCSSValueFilter(t *testing.T) { + tests := []struct { + css, want string + }{ + {"", ""}, + {"foo", "foo"}, + {"0", "0"}, + {"0px", "0px"}, + {"-5px", "-5px"}, + {"1.25in", "1.25in"}, + {"+.33em", "+.33em"}, + {"100%", "100%"}, + {"12.5%", "12.5%"}, + {".foo", ".foo"}, + {"#bar", "#bar"}, + {"corner-radius", "corner-radius"}, + {"-moz-corner-radius", "-moz-corner-radius"}, + {"#000", "#000"}, + {"#48f", "#48f"}, + {"#123456", "#123456"}, + {"U+00-FF, U+980-9FF", "U+00-FF, U+980-9FF"}, + {"color: red", "color: red"}, + {"<!--", "ZgotmplZ"}, + {"-->", "ZgotmplZ"}, + {"<![CDATA[", "ZgotmplZ"}, + {"]]>", "ZgotmplZ"}, + {"</style", "ZgotmplZ"}, + {`"`, "ZgotmplZ"}, + {`'`, "ZgotmplZ"}, + {"`", "ZgotmplZ"}, + {"\x00", "ZgotmplZ"}, + {"/* foo */", "ZgotmplZ"}, + {"//", "ZgotmplZ"}, + {"[href=~", "ZgotmplZ"}, + {"expression(alert(1337))", "ZgotmplZ"}, + {"-expression(alert(1337))", "ZgotmplZ"}, + {"expression", "ZgotmplZ"}, + {"Expression", "ZgotmplZ"}, + {"EXPRESSION", "ZgotmplZ"}, + {"-moz-binding", "ZgotmplZ"}, + {"-expr\x00ession(alert(1337))", "ZgotmplZ"}, + {`-expr\0ession(alert(1337))`, "ZgotmplZ"}, + {`-express\69on(alert(1337))`, "ZgotmplZ"}, + {`-express\69 on(alert(1337))`, "ZgotmplZ"}, + {`-exp\72 ession(alert(1337))`, "ZgotmplZ"}, + {`-exp\52 ession(alert(1337))`, "ZgotmplZ"}, + {`-exp\000052 ession(alert(1337))`, "ZgotmplZ"}, + {`-expre\0000073sion`, "-expre\x073sion"}, + {`@import url evil.css`, "ZgotmplZ"}, + } + for _, test := range tests { + got := cssValueFilter(test.css) + if got != test.want { + t.Errorf("%q: want %q but got %q", test.css, test.want, got) + } + } +} + +func BenchmarkCSSEscaper(b *testing.B) { + for i := 0; i < b.N; i++ { + cssEscaper("The <i>quick</i>,\r\n<span style='color:brown'>brown</span> fox jumps\u2028over the <canine class=\"lazy\">dog</canine>") + } +} + +func BenchmarkCSSEscaperNoSpecials(b *testing.B) { + for i := 0; i < b.N; i++ { + cssEscaper("The quick, brown fox jumps over the lazy dog.") + } +} + +func BenchmarkDecodeCSS(b *testing.B) { + s := []byte(`The \3c i\3equick\3c/i\3e,\d\A\3cspan style=\27 color:brown\27\3e brown\3c/span\3e fox jumps\2028over the \3c canine class=\22lazy\22 \3edog\3c/canine\3e`) + b.ResetTimer() + for i := 0; i < b.N; i++ { + decodeCSS(s) + } +} + +func BenchmarkDecodeCSSNoSpecials(b *testing.B) { + s := []byte("The quick, brown fox jumps over the lazy dog.") + b.ResetTimer() + for i := 0; i < b.N; i++ { + decodeCSS(s) + } +} + +func BenchmarkCSSValueFilter(b *testing.B) { + for i := 0; i < b.N; i++ { + cssValueFilter(` e\78preS\0Sio/**/n(alert(1337))`) + } +} + +func BenchmarkCSSValueFilterOk(b *testing.B) { + for i := 0; i < b.N; i++ { + cssValueFilter(`Times New Roman`) + } +} diff --git a/src/html/template/delim_string.go b/src/html/template/delim_string.go new file mode 100644 index 0000000..6d80e09 --- /dev/null +++ b/src/html/template/delim_string.go @@ -0,0 +1,16 @@ +// Code generated by "stringer -type delim"; DO NOT EDIT. + +package template + +import "strconv" + +const _delim_name = "delimNonedelimDoubleQuotedelimSingleQuotedelimSpaceOrTagEnd" + +var _delim_index = [...]uint8{0, 9, 25, 41, 59} + +func (i delim) String() string { + if i >= delim(len(_delim_index)-1) { + return "delim(" + strconv.FormatInt(int64(i), 10) + ")" + } + return _delim_name[_delim_index[i]:_delim_index[i+1]] +} diff --git a/src/html/template/doc.go b/src/html/template/doc.go new file mode 100644 index 0000000..650e714 --- /dev/null +++ b/src/html/template/doc.go @@ -0,0 +1,241 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +/* +Package template (html/template) implements data-driven templates for +generating HTML output safe against code injection. It provides the +same interface as package text/template and should be used instead of +text/template whenever the output is HTML. + +The documentation here focuses on the security features of the package. +For information about how to program the templates themselves, see the +documentation for text/template. + +Introduction + +This package wraps package text/template so you can share its template API +to parse and execute HTML templates safely. + + tmpl, err := template.New("name").Parse(...) + // Error checking elided + err = tmpl.Execute(out, data) + +If successful, tmpl will now be injection-safe. Otherwise, err is an error +defined in the docs for ErrorCode. + +HTML templates treat data values as plain text which should be encoded so they +can be safely embedded in an HTML document. The escaping is contextual, so +actions can appear within JavaScript, CSS, and URI contexts. + +The security model used by this package assumes that template authors are +trusted, while Execute's data parameter is not. More details are +provided below. + +Example + + import "text/template" + ... + t, err := template.New("foo").Parse(`{{define "T"}}Hello, {{.}}!{{end}}`) + err = t.ExecuteTemplate(out, "T", "<script>alert('you have been pwned')</script>") + +produces + + Hello, <script>alert('you have been pwned')</script>! + +but the contextual autoescaping in html/template + + import "html/template" + ... + t, err := template.New("foo").Parse(`{{define "T"}}Hello, {{.}}!{{end}}`) + err = t.ExecuteTemplate(out, "T", "<script>alert('you have been pwned')</script>") + +produces safe, escaped HTML output + + Hello, <script>alert('you have been pwned')</script>! + + +Contexts + +This package understands HTML, CSS, JavaScript, and URIs. It adds sanitizing +functions to each simple action pipeline, so given the excerpt + + <a href="/search?q={{.}}">{{.}}</a> + +At parse time each {{.}} is overwritten to add escaping functions as necessary. +In this case it becomes + + <a href="/search?q={{. | urlescaper | attrescaper}}">{{. | htmlescaper}}</a> + +where urlescaper, attrescaper, and htmlescaper are aliases for internal escaping +functions. + +For these internal escaping functions, if an action pipeline evaluates to +a nil interface value, it is treated as though it were an empty string. + +Namespaced and data- attributes + +Attributes with a namespace are treated as if they had no namespace. +Given the excerpt + + <a my:href="{{.}}"></a> + +At parse time the attribute will be treated as if it were just "href". +So at parse time the template becomes: + + <a my:href="{{. | urlescaper | attrescaper}}"></a> + +Similarly to attributes with namespaces, attributes with a "data-" prefix are +treated as if they had no "data-" prefix. So given + + <a data-href="{{.}}"></a> + +At parse time this becomes + + <a data-href="{{. | urlescaper | attrescaper}}"></a> + +If an attribute has both a namespace and a "data-" prefix, only the namespace +will be removed when determining the context. For example + + <a my:data-href="{{.}}"></a> + +This is handled as if "my:data-href" was just "data-href" and not "href" as +it would be if the "data-" prefix were to be ignored too. Thus at parse +time this becomes just + + <a my:data-href="{{. | attrescaper}}"></a> + +As a special case, attributes with the namespace "xmlns" are always treated +as containing URLs. Given the excerpts + + <a xmlns:title="{{.}}"></a> + <a xmlns:href="{{.}}"></a> + <a xmlns:onclick="{{.}}"></a> + +At parse time they become: + + <a xmlns:title="{{. | urlescaper | attrescaper}}"></a> + <a xmlns:href="{{. | urlescaper | attrescaper}}"></a> + <a xmlns:onclick="{{. | urlescaper | attrescaper}}"></a> + +Errors + +See the documentation of ErrorCode for details. + + +A fuller picture + +The rest of this package comment may be skipped on first reading; it includes +details necessary to understand escaping contexts and error messages. Most users +will not need to understand these details. + + +Contexts + +Assuming {{.}} is `O'Reilly: How are <i>you</i>?`, the table below shows +how {{.}} appears when used in the context to the left. + + Context {{.}} After + {{.}} O'Reilly: How are <i>you</i>? + <a title='{{.}}'> O'Reilly: How are you? + <a href="/{{.}}"> O'Reilly: How are %3ci%3eyou%3c/i%3e? + <a href="?q={{.}}"> O'Reilly%3a%20How%20are%3ci%3e...%3f + <a onx='f("{{.}}")'> O\x27Reilly: How are \x3ci\x3eyou...? + <a onx='f({{.}})'> "O\x27Reilly: How are \x3ci\x3eyou...?" + <a onx='pattern = /{{.}}/;'> O\x27Reilly: How are \x3ci\x3eyou...\x3f + +If used in an unsafe context, then the value might be filtered out: + + Context {{.}} After + <a href="{{.}}"> #ZgotmplZ + +since "O'Reilly:" is not an allowed protocol like "http:". + + +If {{.}} is the innocuous word, `left`, then it can appear more widely, + + Context {{.}} After + {{.}} left + <a title='{{.}}'> left + <a href='{{.}}'> left + <a href='/{{.}}'> left + <a href='?dir={{.}}'> left + <a style="border-{{.}}: 4px"> left + <a style="align: {{.}}"> left + <a style="background: '{{.}}'> left + <a style="background: url('{{.}}')> left + <style>p.{{.}} {color:red}</style> left + +Non-string values can be used in JavaScript contexts. +If {{.}} is + + struct{A,B string}{ "foo", "bar" } + +in the escaped template + + <script>var pair = {{.}};</script> + +then the template output is + + <script>var pair = {"A": "foo", "B": "bar"};</script> + +See package json to understand how non-string content is marshaled for +embedding in JavaScript contexts. + + +Typed Strings + +By default, this package assumes that all pipelines produce a plain text string. +It adds escaping pipeline stages necessary to correctly and safely embed that +plain text string in the appropriate context. + +When a data value is not plain text, you can make sure it is not over-escaped +by marking it with its type. + +Types HTML, JS, URL, and others from content.go can carry safe content that is +exempted from escaping. + +The template + + Hello, {{.}}! + +can be invoked with + + tmpl.Execute(out, template.HTML(`<b>World</b>`)) + +to produce + + Hello, <b>World</b>! + +instead of the + + Hello, <b>World<b>! + +that would have been produced if {{.}} was a regular string. + + +Security Model + +https://rawgit.com/mikesamuel/sanitized-jquery-templates/trunk/safetemplate.html#problem_definition defines "safe" as used by this package. + +This package assumes that template authors are trusted, that Execute's data +parameter is not, and seeks to preserve the properties below in the face +of untrusted data: + +Structure Preservation Property: +"... when a template author writes an HTML tag in a safe templating language, +the browser will interpret the corresponding portion of the output as a tag +regardless of the values of untrusted data, and similarly for other structures +such as attribute boundaries and JS and CSS string boundaries." + +Code Effect Property: +"... only code specified by the template author should run as a result of +injecting the template output into a page and all code specified by the +template author should run as a result of the same." + +Least Surprise Property: +"A developer (or code reviewer) familiar with HTML, CSS, and JavaScript, who +knows that contextual autoescaping happens should be able to look at a {{.}} +and correctly infer what sanitization happens." +*/ +package template diff --git a/src/html/template/element_string.go b/src/html/template/element_string.go new file mode 100644 index 0000000..4573e08 --- /dev/null +++ b/src/html/template/element_string.go @@ -0,0 +1,16 @@ +// Code generated by "stringer -type element"; DO NOT EDIT. + +package template + +import "strconv" + +const _element_name = "elementNoneelementScriptelementStyleelementTextareaelementTitle" + +var _element_index = [...]uint8{0, 11, 24, 36, 51, 63} + +func (i element) String() string { + if i >= element(len(_element_index)-1) { + return "element(" + strconv.FormatInt(int64(i), 10) + ")" + } + return _element_name[_element_index[i]:_element_index[i+1]] +} diff --git a/src/html/template/error.go b/src/html/template/error.go new file mode 100644 index 0000000..0e52706 --- /dev/null +++ b/src/html/template/error.go @@ -0,0 +1,233 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package template + +import ( + "fmt" + "text/template/parse" +) + +// Error describes a problem encountered during template Escaping. +type Error struct { + // ErrorCode describes the kind of error. + ErrorCode ErrorCode + // Node is the node that caused the problem, if known. + // If not nil, it overrides Name and Line. + Node parse.Node + // Name is the name of the template in which the error was encountered. + Name string + // Line is the line number of the error in the template source or 0. + Line int + // Description is a human-readable description of the problem. + Description string +} + +// ErrorCode is a code for a kind of error. +type ErrorCode int + +// We define codes for each error that manifests while escaping templates, but +// escaped templates may also fail at runtime. +// +// Output: "ZgotmplZ" +// Example: +// <img src="{{.X}}"> +// where {{.X}} evaluates to `javascript:...` +// Discussion: +// "ZgotmplZ" is a special value that indicates that unsafe content reached a +// CSS or URL context at runtime. The output of the example will be +// <img src="#ZgotmplZ"> +// If the data comes from a trusted source, use content types to exempt it +// from filtering: URL(`javascript:...`). +const ( + // OK indicates the lack of an error. + OK ErrorCode = iota + + // ErrAmbigContext: "... appears in an ambiguous context within a URL" + // Example: + // <a href=" + // {{if .C}} + // /path/ + // {{else}} + // /search?q= + // {{end}} + // {{.X}} + // "> + // Discussion: + // {{.X}} is in an ambiguous URL context since, depending on {{.C}}, + // it may be either a URL suffix or a query parameter. + // Moving {{.X}} into the condition removes the ambiguity: + // <a href="{{if .C}}/path/{{.X}}{{else}}/search?q={{.X}}"> + ErrAmbigContext + + // ErrBadHTML: "expected space, attr name, or end of tag, but got ...", + // "... in unquoted attr", "... in attribute name" + // Example: + // <a href = /search?q=foo> + // <href=foo> + // <form na<e=...> + // <option selected< + // Discussion: + // This is often due to a typo in an HTML element, but some runes + // are banned in tag names, attribute names, and unquoted attribute + // values because they can tickle parser ambiguities. + // Quoting all attributes is the best policy. + ErrBadHTML + + // ErrBranchEnd: "{{if}} branches end in different contexts" + // Example: + // {{if .C}}<a href="{{end}}{{.X}} + // Discussion: + // Package html/template statically examines each path through an + // {{if}}, {{range}}, or {{with}} to escape any following pipelines. + // The example is ambiguous since {{.X}} might be an HTML text node, + // or a URL prefix in an HTML attribute. The context of {{.X}} is + // used to figure out how to escape it, but that context depends on + // the run-time value of {{.C}} which is not statically known. + // + // The problem is usually something like missing quotes or angle + // brackets, or can be avoided by refactoring to put the two contexts + // into different branches of an if, range or with. If the problem + // is in a {{range}} over a collection that should never be empty, + // adding a dummy {{else}} can help. + ErrBranchEnd + + // ErrEndContext: "... ends in a non-text context: ..." + // Examples: + // <div + // <div title="no close quote> + // <script>f() + // Discussion: + // Executed templates should produce a DocumentFragment of HTML. + // Templates that end without closing tags will trigger this error. + // Templates that should not be used in an HTML context or that + // produce incomplete Fragments should not be executed directly. + // + // {{define "main"}} <script>{{template "helper"}}</script> {{end}} + // {{define "helper"}} document.write(' <div title=" ') {{end}} + // + // "helper" does not produce a valid document fragment, so should + // not be Executed directly. + ErrEndContext + + // ErrNoSuchTemplate: "no such template ..." + // Examples: + // {{define "main"}}<div {{template "attrs"}}>{{end}} + // {{define "attrs"}}href="{{.URL}}"{{end}} + // Discussion: + // Package html/template looks through template calls to compute the + // context. + // Here the {{.URL}} in "attrs" must be treated as a URL when called + // from "main", but you will get this error if "attrs" is not defined + // when "main" is parsed. + ErrNoSuchTemplate + + // ErrOutputContext: "cannot compute output context for template ..." + // Examples: + // {{define "t"}}{{if .T}}{{template "t" .T}}{{end}}{{.H}}",{{end}} + // Discussion: + // A recursive template does not end in the same context in which it + // starts, and a reliable output context cannot be computed. + // Look for typos in the named template. + // If the template should not be called in the named start context, + // look for calls to that template in unexpected contexts. + // Maybe refactor recursive templates to not be recursive. + ErrOutputContext + + // ErrPartialCharset: "unfinished JS regexp charset in ..." + // Example: + // <script>var pattern = /foo[{{.Chars}}]/</script> + // Discussion: + // Package html/template does not support interpolation into regular + // expression literal character sets. + ErrPartialCharset + + // ErrPartialEscape: "unfinished escape sequence in ..." + // Example: + // <script>alert("\{{.X}}")</script> + // Discussion: + // Package html/template does not support actions following a + // backslash. + // This is usually an error and there are better solutions; for + // example + // <script>alert("{{.X}}")</script> + // should work, and if {{.X}} is a partial escape sequence such as + // "xA0", mark the whole sequence as safe content: JSStr(`\xA0`) + ErrPartialEscape + + // ErrRangeLoopReentry: "on range loop re-entry: ..." + // Example: + // <script>var x = [{{range .}}'{{.}},{{end}}]</script> + // Discussion: + // If an iteration through a range would cause it to end in a + // different context than an earlier pass, there is no single context. + // In the example, there is missing a quote, so it is not clear + // whether {{.}} is meant to be inside a JS string or in a JS value + // context. The second iteration would produce something like + // + // <script>var x = ['firstValue,'secondValue]</script> + ErrRangeLoopReentry + + // ErrSlashAmbig: '/' could start a division or regexp. + // Example: + // <script> + // {{if .C}}var x = 1{{end}} + // /-{{.N}}/i.test(x) ? doThis : doThat(); + // </script> + // Discussion: + // The example above could produce `var x = 1/-2/i.test(s)...` + // in which the first '/' is a mathematical division operator or it + // could produce `/-2/i.test(s)` in which the first '/' starts a + // regexp literal. + // Look for missing semicolons inside branches, and maybe add + // parentheses to make it clear which interpretation you intend. + ErrSlashAmbig + + // ErrPredefinedEscaper: "predefined escaper ... disallowed in template" + // Example: + // <div class={{. | html}}>Hello<div> + // Discussion: + // Package html/template already contextually escapes all pipelines to + // produce HTML output safe against code injection. Manually escaping + // pipeline output using the predefined escapers "html" or "urlquery" is + // unnecessary, and may affect the correctness or safety of the escaped + // pipeline output in Go 1.8 and earlier. + // + // In most cases, such as the given example, this error can be resolved by + // simply removing the predefined escaper from the pipeline and letting the + // contextual autoescaper handle the escaping of the pipeline. In other + // instances, where the predefined escaper occurs in the middle of a + // pipeline where subsequent commands expect escaped input, e.g. + // {{.X | html | makeALink}} + // where makeALink does + // return `<a href="`+input+`">link</a>` + // consider refactoring the surrounding template to make use of the + // contextual autoescaper, i.e. + // <a href="{{.X}}">link</a> + // + // To ease migration to Go 1.9 and beyond, "html" and "urlquery" will + // continue to be allowed as the last command in a pipeline. However, if the + // pipeline occurs in an unquoted attribute value context, "html" is + // disallowed. Avoid using "html" and "urlquery" entirely in new templates. + ErrPredefinedEscaper +) + +func (e *Error) Error() string { + switch { + case e.Node != nil: + loc, _ := (*parse.Tree)(nil).ErrorContext(e.Node) + return fmt.Sprintf("html/template:%s: %s", loc, e.Description) + case e.Line != 0: + return fmt.Sprintf("html/template:%s:%d: %s", e.Name, e.Line, e.Description) + case e.Name != "": + return fmt.Sprintf("html/template:%s: %s", e.Name, e.Description) + } + return "html/template: " + e.Description +} + +// errorf creates an error given a format string f and args. +// The template Name still needs to be supplied. +func errorf(k ErrorCode, node parse.Node, line int, f string, args ...interface{}) *Error { + return &Error{k, node, "", line, fmt.Sprintf(f, args...)} +} diff --git a/src/html/template/escape.go b/src/html/template/escape.go new file mode 100644 index 0000000..8739735 --- /dev/null +++ b/src/html/template/escape.go @@ -0,0 +1,892 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package template + +import ( + "bytes" + "fmt" + "html" + "io" + "text/template" + "text/template/parse" +) + +// escapeTemplate rewrites the named template, which must be +// associated with t, to guarantee that the output of any of the named +// templates is properly escaped. If no error is returned, then the named templates have +// been modified. Otherwise the named templates have been rendered +// unusable. +func escapeTemplate(tmpl *Template, node parse.Node, name string) error { + c, _ := tmpl.esc.escapeTree(context{}, node, name, 0) + var err error + if c.err != nil { + err, c.err.Name = c.err, name + } else if c.state != stateText { + err = &Error{ErrEndContext, nil, name, 0, fmt.Sprintf("ends in a non-text context: %v", c)} + } + if err != nil { + // Prevent execution of unsafe templates. + if t := tmpl.set[name]; t != nil { + t.escapeErr = err + t.text.Tree = nil + t.Tree = nil + } + return err + } + tmpl.esc.commit() + if t := tmpl.set[name]; t != nil { + t.escapeErr = escapeOK + t.Tree = t.text.Tree + } + return nil +} + +// evalArgs formats the list of arguments into a string. It is equivalent to +// fmt.Sprint(args...), except that it deferences all pointers. +func evalArgs(args ...interface{}) string { + // Optimization for simple common case of a single string argument. + if len(args) == 1 { + if s, ok := args[0].(string); ok { + return s + } + } + for i, arg := range args { + args[i] = indirectToStringerOrError(arg) + } + return fmt.Sprint(args...) +} + +// funcMap maps command names to functions that render their inputs safe. +var funcMap = template.FuncMap{ + "_html_template_attrescaper": attrEscaper, + "_html_template_commentescaper": commentEscaper, + "_html_template_cssescaper": cssEscaper, + "_html_template_cssvaluefilter": cssValueFilter, + "_html_template_htmlnamefilter": htmlNameFilter, + "_html_template_htmlescaper": htmlEscaper, + "_html_template_jsregexpescaper": jsRegexpEscaper, + "_html_template_jsstrescaper": jsStrEscaper, + "_html_template_jsvalescaper": jsValEscaper, + "_html_template_nospaceescaper": htmlNospaceEscaper, + "_html_template_rcdataescaper": rcdataEscaper, + "_html_template_srcsetescaper": srcsetFilterAndEscaper, + "_html_template_urlescaper": urlEscaper, + "_html_template_urlfilter": urlFilter, + "_html_template_urlnormalizer": urlNormalizer, + "_eval_args_": evalArgs, +} + +// escaper collects type inferences about templates and changes needed to make +// templates injection safe. +type escaper struct { + // ns is the nameSpace that this escaper is associated with. + ns *nameSpace + // output[templateName] is the output context for a templateName that + // has been mangled to include its input context. + output map[string]context + // derived[c.mangle(name)] maps to a template derived from the template + // named name templateName for the start context c. + derived map[string]*template.Template + // called[templateName] is a set of called mangled template names. + called map[string]bool + // xxxNodeEdits are the accumulated edits to apply during commit. + // Such edits are not applied immediately in case a template set + // executes a given template in different escaping contexts. + actionNodeEdits map[*parse.ActionNode][]string + templateNodeEdits map[*parse.TemplateNode]string + textNodeEdits map[*parse.TextNode][]byte +} + +// makeEscaper creates a blank escaper for the given set. +func makeEscaper(n *nameSpace) escaper { + return escaper{ + n, + map[string]context{}, + map[string]*template.Template{}, + map[string]bool{}, + map[*parse.ActionNode][]string{}, + map[*parse.TemplateNode]string{}, + map[*parse.TextNode][]byte{}, + } +} + +// filterFailsafe is an innocuous word that is emitted in place of unsafe values +// by sanitizer functions. It is not a keyword in any programming language, +// contains no special characters, is not empty, and when it appears in output +// it is distinct enough that a developer can find the source of the problem +// via a search engine. +const filterFailsafe = "ZgotmplZ" + +// escape escapes a template node. +func (e *escaper) escape(c context, n parse.Node) context { + switch n := n.(type) { + case *parse.ActionNode: + return e.escapeAction(c, n) + case *parse.CommentNode: + return c + case *parse.IfNode: + return e.escapeBranch(c, &n.BranchNode, "if") + case *parse.ListNode: + return e.escapeList(c, n) + case *parse.RangeNode: + return e.escapeBranch(c, &n.BranchNode, "range") + case *parse.TemplateNode: + return e.escapeTemplate(c, n) + case *parse.TextNode: + return e.escapeText(c, n) + case *parse.WithNode: + return e.escapeBranch(c, &n.BranchNode, "with") + } + panic("escaping " + n.String() + " is unimplemented") +} + +// escapeAction escapes an action template node. +func (e *escaper) escapeAction(c context, n *parse.ActionNode) context { + if len(n.Pipe.Decl) != 0 { + // A local variable assignment, not an interpolation. + return c + } + c = nudge(c) + // Check for disallowed use of predefined escapers in the pipeline. + for pos, idNode := range n.Pipe.Cmds { + node, ok := idNode.Args[0].(*parse.IdentifierNode) + if !ok { + // A predefined escaper "esc" will never be found as an identifier in a + // Chain or Field node, since: + // - "esc.x ..." is invalid, since predefined escapers return strings, and + // strings do not have methods, keys or fields. + // - "... .esc" is invalid, since predefined escapers are global functions, + // not methods or fields of any types. + // Therefore, it is safe to ignore these two node types. + continue + } + ident := node.Ident + if _, ok := predefinedEscapers[ident]; ok { + if pos < len(n.Pipe.Cmds)-1 || + c.state == stateAttr && c.delim == delimSpaceOrTagEnd && ident == "html" { + return context{ + state: stateError, + err: errorf(ErrPredefinedEscaper, n, n.Line, "predefined escaper %q disallowed in template", ident), + } + } + } + } + s := make([]string, 0, 3) + switch c.state { + case stateError: + return c + case stateURL, stateCSSDqStr, stateCSSSqStr, stateCSSDqURL, stateCSSSqURL, stateCSSURL: + switch c.urlPart { + case urlPartNone: + s = append(s, "_html_template_urlfilter") + fallthrough + case urlPartPreQuery: + switch c.state { + case stateCSSDqStr, stateCSSSqStr: + s = append(s, "_html_template_cssescaper") + default: + s = append(s, "_html_template_urlnormalizer") + } + case urlPartQueryOrFrag: + s = append(s, "_html_template_urlescaper") + case urlPartUnknown: + return context{ + state: stateError, + err: errorf(ErrAmbigContext, n, n.Line, "%s appears in an ambiguous context within a URL", n), + } + default: + panic(c.urlPart.String()) + } + case stateJS: + s = append(s, "_html_template_jsvalescaper") + // A slash after a value starts a div operator. + c.jsCtx = jsCtxDivOp + case stateJSDqStr, stateJSSqStr: + s = append(s, "_html_template_jsstrescaper") + case stateJSRegexp: + s = append(s, "_html_template_jsregexpescaper") + case stateCSS: + s = append(s, "_html_template_cssvaluefilter") + case stateText: + s = append(s, "_html_template_htmlescaper") + case stateRCDATA: + s = append(s, "_html_template_rcdataescaper") + case stateAttr: + // Handled below in delim check. + case stateAttrName, stateTag: + c.state = stateAttrName + s = append(s, "_html_template_htmlnamefilter") + case stateSrcset: + s = append(s, "_html_template_srcsetescaper") + default: + if isComment(c.state) { + s = append(s, "_html_template_commentescaper") + } else { + panic("unexpected state " + c.state.String()) + } + } + switch c.delim { + case delimNone: + // No extra-escaping needed for raw text content. + case delimSpaceOrTagEnd: + s = append(s, "_html_template_nospaceescaper") + default: + s = append(s, "_html_template_attrescaper") + } + e.editActionNode(n, s) + return c +} + +// ensurePipelineContains ensures that the pipeline ends with the commands with +// the identifiers in s in order. If the pipeline ends with a predefined escaper +// (i.e. "html" or "urlquery"), merge it with the identifiers in s. +func ensurePipelineContains(p *parse.PipeNode, s []string) { + if len(s) == 0 { + // Do not rewrite pipeline if we have no escapers to insert. + return + } + // Precondition: p.Cmds contains at most one predefined escaper and the + // escaper will be present at p.Cmds[len(p.Cmds)-1]. This precondition is + // always true because of the checks in escapeAction. + pipelineLen := len(p.Cmds) + if pipelineLen > 0 { + lastCmd := p.Cmds[pipelineLen-1] + if idNode, ok := lastCmd.Args[0].(*parse.IdentifierNode); ok { + if esc := idNode.Ident; predefinedEscapers[esc] { + // Pipeline ends with a predefined escaper. + if len(p.Cmds) == 1 && len(lastCmd.Args) > 1 { + // Special case: pipeline is of the form {{ esc arg1 arg2 ... argN }}, + // where esc is the predefined escaper, and arg1...argN are its arguments. + // Convert this into the equivalent form + // {{ _eval_args_ arg1 arg2 ... argN | esc }}, so that esc can be easily + // merged with the escapers in s. + lastCmd.Args[0] = parse.NewIdentifier("_eval_args_").SetTree(nil).SetPos(lastCmd.Args[0].Position()) + p.Cmds = appendCmd(p.Cmds, newIdentCmd(esc, p.Position())) + pipelineLen++ + } + // If any of the commands in s that we are about to insert is equivalent + // to the predefined escaper, use the predefined escaper instead. + dup := false + for i, escaper := range s { + if escFnsEq(esc, escaper) { + s[i] = idNode.Ident + dup = true + } + } + if dup { + // The predefined escaper will already be inserted along with the + // escapers in s, so do not copy it to the rewritten pipeline. + pipelineLen-- + } + } + } + } + // Rewrite the pipeline, creating the escapers in s at the end of the pipeline. + newCmds := make([]*parse.CommandNode, pipelineLen, pipelineLen+len(s)) + insertedIdents := make(map[string]bool) + for i := 0; i < pipelineLen; i++ { + cmd := p.Cmds[i] + newCmds[i] = cmd + if idNode, ok := cmd.Args[0].(*parse.IdentifierNode); ok { + insertedIdents[normalizeEscFn(idNode.Ident)] = true + } + } + for _, name := range s { + if !insertedIdents[normalizeEscFn(name)] { + // When two templates share an underlying parse tree via the use of + // AddParseTree and one template is executed after the other, this check + // ensures that escapers that were already inserted into the pipeline on + // the first escaping pass do not get inserted again. + newCmds = appendCmd(newCmds, newIdentCmd(name, p.Position())) + } + } + p.Cmds = newCmds +} + +// predefinedEscapers contains template predefined escapers that are equivalent +// to some contextual escapers. Keep in sync with equivEscapers. +var predefinedEscapers = map[string]bool{ + "html": true, + "urlquery": true, +} + +// equivEscapers matches contextual escapers to equivalent predefined +// template escapers. +var equivEscapers = map[string]string{ + // The following pairs of HTML escapers provide equivalent security + // guarantees, since they all escape '\000', '\'', '"', '&', '<', and '>'. + "_html_template_attrescaper": "html", + "_html_template_htmlescaper": "html", + "_html_template_rcdataescaper": "html", + // These two URL escapers produce URLs safe for embedding in a URL query by + // percent-encoding all the reserved characters specified in RFC 3986 Section + // 2.2 + "_html_template_urlescaper": "urlquery", + // These two functions are not actually equivalent; urlquery is stricter as it + // escapes reserved characters (e.g. '#'), while _html_template_urlnormalizer + // does not. It is therefore only safe to replace _html_template_urlnormalizer + // with urlquery (this happens in ensurePipelineContains), but not the otherI've + // way around. We keep this entry around to preserve the behavior of templates + // written before Go 1.9, which might depend on this substitution taking place. + "_html_template_urlnormalizer": "urlquery", +} + +// escFnsEq reports whether the two escaping functions are equivalent. +func escFnsEq(a, b string) bool { + return normalizeEscFn(a) == normalizeEscFn(b) +} + +// normalizeEscFn(a) is equal to normalizeEscFn(b) for any pair of names of +// escaper functions a and b that are equivalent. +func normalizeEscFn(e string) string { + if norm := equivEscapers[e]; norm != "" { + return norm + } + return e +} + +// redundantFuncs[a][b] implies that funcMap[b](funcMap[a](x)) == funcMap[a](x) +// for all x. +var redundantFuncs = map[string]map[string]bool{ + "_html_template_commentescaper": { + "_html_template_attrescaper": true, + "_html_template_nospaceescaper": true, + "_html_template_htmlescaper": true, + }, + "_html_template_cssescaper": { + "_html_template_attrescaper": true, + }, + "_html_template_jsregexpescaper": { + "_html_template_attrescaper": true, + }, + "_html_template_jsstrescaper": { + "_html_template_attrescaper": true, + }, + "_html_template_urlescaper": { + "_html_template_urlnormalizer": true, + }, +} + +// appendCmd appends the given command to the end of the command pipeline +// unless it is redundant with the last command. +func appendCmd(cmds []*parse.CommandNode, cmd *parse.CommandNode) []*parse.CommandNode { + if n := len(cmds); n != 0 { + last, okLast := cmds[n-1].Args[0].(*parse.IdentifierNode) + next, okNext := cmd.Args[0].(*parse.IdentifierNode) + if okLast && okNext && redundantFuncs[last.Ident][next.Ident] { + return cmds + } + } + return append(cmds, cmd) +} + +// newIdentCmd produces a command containing a single identifier node. +func newIdentCmd(identifier string, pos parse.Pos) *parse.CommandNode { + return &parse.CommandNode{ + NodeType: parse.NodeCommand, + Args: []parse.Node{parse.NewIdentifier(identifier).SetTree(nil).SetPos(pos)}, // TODO: SetTree. + } +} + +// nudge returns the context that would result from following empty string +// transitions from the input context. +// For example, parsing: +// `<a href=` +// will end in context{stateBeforeValue, attrURL}, but parsing one extra rune: +// `<a href=x` +// will end in context{stateURL, delimSpaceOrTagEnd, ...}. +// There are two transitions that happen when the 'x' is seen: +// (1) Transition from a before-value state to a start-of-value state without +// consuming any character. +// (2) Consume 'x' and transition past the first value character. +// In this case, nudging produces the context after (1) happens. +func nudge(c context) context { + switch c.state { + case stateTag: + // In `<foo {{.}}`, the action should emit an attribute. + c.state = stateAttrName + case stateBeforeValue: + // In `<foo bar={{.}}`, the action is an undelimited value. + c.state, c.delim, c.attr = attrStartStates[c.attr], delimSpaceOrTagEnd, attrNone + case stateAfterName: + // In `<foo bar {{.}}`, the action is an attribute name. + c.state, c.attr = stateAttrName, attrNone + } + return c +} + +// join joins the two contexts of a branch template node. The result is an +// error context if either of the input contexts are error contexts, or if the +// input contexts differ. +func join(a, b context, node parse.Node, nodeName string) context { + if a.state == stateError { + return a + } + if b.state == stateError { + return b + } + if a.eq(b) { + return a + } + + c := a + c.urlPart = b.urlPart + if c.eq(b) { + // The contexts differ only by urlPart. + c.urlPart = urlPartUnknown + return c + } + + c = a + c.jsCtx = b.jsCtx + if c.eq(b) { + // The contexts differ only by jsCtx. + c.jsCtx = jsCtxUnknown + return c + } + + // Allow a nudged context to join with an unnudged one. + // This means that + // <p title={{if .C}}{{.}}{{end}} + // ends in an unquoted value state even though the else branch + // ends in stateBeforeValue. + if c, d := nudge(a), nudge(b); !(c.eq(a) && d.eq(b)) { + if e := join(c, d, node, nodeName); e.state != stateError { + return e + } + } + + return context{ + state: stateError, + err: errorf(ErrBranchEnd, node, 0, "{{%s}} branches end in different contexts: %v, %v", nodeName, a, b), + } +} + +// escapeBranch escapes a branch template node: "if", "range" and "with". +func (e *escaper) escapeBranch(c context, n *parse.BranchNode, nodeName string) context { + c0 := e.escapeList(c, n.List) + if nodeName == "range" && c0.state != stateError { + // The "true" branch of a "range" node can execute multiple times. + // We check that executing n.List once results in the same context + // as executing n.List twice. + c1, _ := e.escapeListConditionally(c0, n.List, nil) + c0 = join(c0, c1, n, nodeName) + if c0.state == stateError { + // Make clear that this is a problem on loop re-entry + // since developers tend to overlook that branch when + // debugging templates. + c0.err.Line = n.Line + c0.err.Description = "on range loop re-entry: " + c0.err.Description + return c0 + } + } + c1 := e.escapeList(c, n.ElseList) + return join(c0, c1, n, nodeName) +} + +// escapeList escapes a list template node. +func (e *escaper) escapeList(c context, n *parse.ListNode) context { + if n == nil { + return c + } + for _, m := range n.Nodes { + c = e.escape(c, m) + } + return c +} + +// escapeListConditionally escapes a list node but only preserves edits and +// inferences in e if the inferences and output context satisfy filter. +// It returns the best guess at an output context, and the result of the filter +// which is the same as whether e was updated. +func (e *escaper) escapeListConditionally(c context, n *parse.ListNode, filter func(*escaper, context) bool) (context, bool) { + e1 := makeEscaper(e.ns) + // Make type inferences available to f. + for k, v := range e.output { + e1.output[k] = v + } + c = e1.escapeList(c, n) + ok := filter != nil && filter(&e1, c) + if ok { + // Copy inferences and edits from e1 back into e. + for k, v := range e1.output { + e.output[k] = v + } + for k, v := range e1.derived { + e.derived[k] = v + } + for k, v := range e1.called { + e.called[k] = v + } + for k, v := range e1.actionNodeEdits { + e.editActionNode(k, v) + } + for k, v := range e1.templateNodeEdits { + e.editTemplateNode(k, v) + } + for k, v := range e1.textNodeEdits { + e.editTextNode(k, v) + } + } + return c, ok +} + +// escapeTemplate escapes a {{template}} call node. +func (e *escaper) escapeTemplate(c context, n *parse.TemplateNode) context { + c, name := e.escapeTree(c, n, n.Name, n.Line) + if name != n.Name { + e.editTemplateNode(n, name) + } + return c +} + +// escapeTree escapes the named template starting in the given context as +// necessary and returns its output context. +func (e *escaper) escapeTree(c context, node parse.Node, name string, line int) (context, string) { + // Mangle the template name with the input context to produce a reliable + // identifier. + dname := c.mangle(name) + e.called[dname] = true + if out, ok := e.output[dname]; ok { + // Already escaped. + return out, dname + } + t := e.template(name) + if t == nil { + // Two cases: The template exists but is empty, or has never been mentioned at + // all. Distinguish the cases in the error messages. + if e.ns.set[name] != nil { + return context{ + state: stateError, + err: errorf(ErrNoSuchTemplate, node, line, "%q is an incomplete or empty template", name), + }, dname + } + return context{ + state: stateError, + err: errorf(ErrNoSuchTemplate, node, line, "no such template %q", name), + }, dname + } + if dname != name { + // Use any template derived during an earlier call to escapeTemplate + // with different top level templates, or clone if necessary. + dt := e.template(dname) + if dt == nil { + dt = template.New(dname) + dt.Tree = &parse.Tree{Name: dname, Root: t.Root.CopyList()} + e.derived[dname] = dt + } + t = dt + } + return e.computeOutCtx(c, t), dname +} + +// computeOutCtx takes a template and its start context and computes the output +// context while storing any inferences in e. +func (e *escaper) computeOutCtx(c context, t *template.Template) context { + // Propagate context over the body. + c1, ok := e.escapeTemplateBody(c, t) + if !ok { + // Look for a fixed point by assuming c1 as the output context. + if c2, ok2 := e.escapeTemplateBody(c1, t); ok2 { + c1, ok = c2, true + } + // Use c1 as the error context if neither assumption worked. + } + if !ok && c1.state != stateError { + return context{ + state: stateError, + err: errorf(ErrOutputContext, t.Tree.Root, 0, "cannot compute output context for template %s", t.Name()), + } + } + return c1 +} + +// escapeTemplateBody escapes the given template assuming the given output +// context, and returns the best guess at the output context and whether the +// assumption was correct. +func (e *escaper) escapeTemplateBody(c context, t *template.Template) (context, bool) { + filter := func(e1 *escaper, c1 context) bool { + if c1.state == stateError { + // Do not update the input escaper, e. + return false + } + if !e1.called[t.Name()] { + // If t is not recursively called, then c1 is an + // accurate output context. + return true + } + // c1 is accurate if it matches our assumed output context. + return c.eq(c1) + } + // We need to assume an output context so that recursive template calls + // take the fast path out of escapeTree instead of infinitely recursing. + // Naively assuming that the input context is the same as the output + // works >90% of the time. + e.output[t.Name()] = c + return e.escapeListConditionally(c, t.Tree.Root, filter) +} + +// delimEnds maps each delim to a string of characters that terminate it. +var delimEnds = [...]string{ + delimDoubleQuote: `"`, + delimSingleQuote: "'", + // Determined empirically by running the below in various browsers. + // var div = document.createElement("DIV"); + // for (var i = 0; i < 0x10000; ++i) { + // div.innerHTML = "<span title=x" + String.fromCharCode(i) + "-bar>"; + // if (div.getElementsByTagName("SPAN")[0].title.indexOf("bar") < 0) + // document.write("<p>U+" + i.toString(16)); + // } + delimSpaceOrTagEnd: " \t\n\f\r>", +} + +var doctypeBytes = []byte("<!DOCTYPE") + +// escapeText escapes a text template node. +func (e *escaper) escapeText(c context, n *parse.TextNode) context { + s, written, i, b := n.Text, 0, 0, new(bytes.Buffer) + for i != len(s) { + c1, nread := contextAfterText(c, s[i:]) + i1 := i + nread + if c.state == stateText || c.state == stateRCDATA { + end := i1 + if c1.state != c.state { + for j := end - 1; j >= i; j-- { + if s[j] == '<' { + end = j + break + } + } + } + for j := i; j < end; j++ { + if s[j] == '<' && !bytes.HasPrefix(bytes.ToUpper(s[j:]), doctypeBytes) { + b.Write(s[written:j]) + b.WriteString("<") + written = j + 1 + } + } + } else if isComment(c.state) && c.delim == delimNone { + switch c.state { + case stateJSBlockCmt: + // https://es5.github.com/#x7.4: + // "Comments behave like white space and are + // discarded except that, if a MultiLineComment + // contains a line terminator character, then + // the entire comment is considered to be a + // LineTerminator for purposes of parsing by + // the syntactic grammar." + if bytes.ContainsAny(s[written:i1], "\n\r\u2028\u2029") { + b.WriteByte('\n') + } else { + b.WriteByte(' ') + } + case stateCSSBlockCmt: + b.WriteByte(' ') + } + written = i1 + } + if c.state != c1.state && isComment(c1.state) && c1.delim == delimNone { + // Preserve the portion between written and the comment start. + cs := i1 - 2 + if c1.state == stateHTMLCmt { + // "<!--" instead of "/*" or "//" + cs -= 2 + } + b.Write(s[written:cs]) + written = i1 + } + if i == i1 && c.state == c1.state { + panic(fmt.Sprintf("infinite loop from %v to %v on %q..%q", c, c1, s[:i], s[i:])) + } + c, i = c1, i1 + } + + if written != 0 && c.state != stateError { + if !isComment(c.state) || c.delim != delimNone { + b.Write(n.Text[written:]) + } + e.editTextNode(n, b.Bytes()) + } + return c +} + +// contextAfterText starts in context c, consumes some tokens from the front of +// s, then returns the context after those tokens and the unprocessed suffix. +func contextAfterText(c context, s []byte) (context, int) { + if c.delim == delimNone { + c1, i := tSpecialTagEnd(c, s) + if i == 0 { + // A special end tag (`</script>`) has been seen and + // all content preceding it has been consumed. + return c1, 0 + } + // Consider all content up to any end tag. + return transitionFunc[c.state](c, s[:i]) + } + + // We are at the beginning of an attribute value. + + i := bytes.IndexAny(s, delimEnds[c.delim]) + if i == -1 { + i = len(s) + } + if c.delim == delimSpaceOrTagEnd { + // https://www.w3.org/TR/html5/syntax.html#attribute-value-(unquoted)-state + // lists the runes below as error characters. + // Error out because HTML parsers may differ on whether + // "<a id= onclick=f(" ends inside id's or onclick's value, + // "<a class=`foo " ends inside a value, + // "<a style=font:'Arial'" needs open-quote fixup. + // IE treats '`' as a quotation character. + if j := bytes.IndexAny(s[:i], "\"'<=`"); j >= 0 { + return context{ + state: stateError, + err: errorf(ErrBadHTML, nil, 0, "%q in unquoted attr: %q", s[j:j+1], s[:i]), + }, len(s) + } + } + if i == len(s) { + // Remain inside the attribute. + // Decode the value so non-HTML rules can easily handle + // <button onclick="alert("Hi!")"> + // without having to entity decode token boundaries. + for u := []byte(html.UnescapeString(string(s))); len(u) != 0; { + c1, i1 := transitionFunc[c.state](c, u) + c, u = c1, u[i1:] + } + return c, len(s) + } + + element := c.element + + // If this is a non-JS "type" attribute inside "script" tag, do not treat the contents as JS. + if c.state == stateAttr && c.element == elementScript && c.attr == attrScriptType && !isJSType(string(s[:i])) { + element = elementNone + } + + if c.delim != delimSpaceOrTagEnd { + // Consume any quote. + i++ + } + // On exiting an attribute, we discard all state information + // except the state and element. + return context{state: stateTag, element: element}, i +} + +// editActionNode records a change to an action pipeline for later commit. +func (e *escaper) editActionNode(n *parse.ActionNode, cmds []string) { + if _, ok := e.actionNodeEdits[n]; ok { + panic(fmt.Sprintf("node %s shared between templates", n)) + } + e.actionNodeEdits[n] = cmds +} + +// editTemplateNode records a change to a {{template}} callee for later commit. +func (e *escaper) editTemplateNode(n *parse.TemplateNode, callee string) { + if _, ok := e.templateNodeEdits[n]; ok { + panic(fmt.Sprintf("node %s shared between templates", n)) + } + e.templateNodeEdits[n] = callee +} + +// editTextNode records a change to a text node for later commit. +func (e *escaper) editTextNode(n *parse.TextNode, text []byte) { + if _, ok := e.textNodeEdits[n]; ok { + panic(fmt.Sprintf("node %s shared between templates", n)) + } + e.textNodeEdits[n] = text +} + +// commit applies changes to actions and template calls needed to contextually +// autoescape content and adds any derived templates to the set. +func (e *escaper) commit() { + for name := range e.output { + e.template(name).Funcs(funcMap) + } + // Any template from the name space associated with this escaper can be used + // to add derived templates to the underlying text/template name space. + tmpl := e.arbitraryTemplate() + for _, t := range e.derived { + if _, err := tmpl.text.AddParseTree(t.Name(), t.Tree); err != nil { + panic("error adding derived template") + } + } + for n, s := range e.actionNodeEdits { + ensurePipelineContains(n.Pipe, s) + } + for n, name := range e.templateNodeEdits { + n.Name = name + } + for n, s := range e.textNodeEdits { + n.Text = s + } + // Reset state that is specific to this commit so that the same changes are + // not re-applied to the template on subsequent calls to commit. + e.called = make(map[string]bool) + e.actionNodeEdits = make(map[*parse.ActionNode][]string) + e.templateNodeEdits = make(map[*parse.TemplateNode]string) + e.textNodeEdits = make(map[*parse.TextNode][]byte) +} + +// template returns the named template given a mangled template name. +func (e *escaper) template(name string) *template.Template { + // Any template from the name space associated with this escaper can be used + // to look up templates in the underlying text/template name space. + t := e.arbitraryTemplate().text.Lookup(name) + if t == nil { + t = e.derived[name] + } + return t +} + +// arbitraryTemplate returns an arbitrary template from the name space +// associated with e and panics if no templates are found. +func (e *escaper) arbitraryTemplate() *Template { + for _, t := range e.ns.set { + return t + } + panic("no templates in name space") +} + +// Forwarding functions so that clients need only import this package +// to reach the general escaping functions of text/template. + +// HTMLEscape writes to w the escaped HTML equivalent of the plain text data b. +func HTMLEscape(w io.Writer, b []byte) { + template.HTMLEscape(w, b) +} + +// HTMLEscapeString returns the escaped HTML equivalent of the plain text data s. +func HTMLEscapeString(s string) string { + return template.HTMLEscapeString(s) +} + +// HTMLEscaper returns the escaped HTML equivalent of the textual +// representation of its arguments. +func HTMLEscaper(args ...interface{}) string { + return template.HTMLEscaper(args...) +} + +// JSEscape writes to w the escaped JavaScript equivalent of the plain text data b. +func JSEscape(w io.Writer, b []byte) { + template.JSEscape(w, b) +} + +// JSEscapeString returns the escaped JavaScript equivalent of the plain text data s. +func JSEscapeString(s string) string { + return template.JSEscapeString(s) +} + +// JSEscaper returns the escaped JavaScript equivalent of the textual +// representation of its arguments. +func JSEscaper(args ...interface{}) string { + return template.JSEscaper(args...) +} + +// URLQueryEscaper returns the escaped value of the textual representation of +// its arguments in a form suitable for embedding in a URL query. +func URLQueryEscaper(args ...interface{}) string { + return template.URLQueryEscaper(args...) +} diff --git a/src/html/template/escape_test.go b/src/html/template/escape_test.go new file mode 100644 index 0000000..fbc84a7 --- /dev/null +++ b/src/html/template/escape_test.go @@ -0,0 +1,1969 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package template + +import ( + "bytes" + "encoding/json" + "fmt" + "os" + "strings" + "testing" + "text/template" + "text/template/parse" +) + +type badMarshaler struct{} + +func (x *badMarshaler) MarshalJSON() ([]byte, error) { + // Keys in valid JSON must be double quoted as must all strings. + return []byte("{ foo: 'not quite valid JSON' }"), nil +} + +type goodMarshaler struct{} + +func (x *goodMarshaler) MarshalJSON() ([]byte, error) { + return []byte(`{ "<foo>": "O'Reilly" }`), nil +} + +func TestEscape(t *testing.T) { + data := struct { + F, T bool + C, G, H string + A, E []string + B, M json.Marshaler + N int + U interface{} // untyped nil + Z *int // typed nil + W HTML + }{ + F: false, + T: true, + C: "<Cincinnati>", + G: "<Goodbye>", + H: "<Hello>", + A: []string{"<a>", "<b>"}, + E: []string{}, + N: 42, + B: &badMarshaler{}, + M: &goodMarshaler{}, + U: nil, + Z: nil, + W: HTML(`¡<b class="foo">Hello</b>, <textarea>O'World</textarea>!`), + } + pdata := &data + + tests := []struct { + name string + input string + output string + }{ + { + "if", + "{{if .T}}Hello{{end}}, {{.C}}!", + "Hello, <Cincinnati>!", + }, + { + "else", + "{{if .F}}{{.H}}{{else}}{{.G}}{{end}}!", + "<Goodbye>!", + }, + { + "overescaping1", + "Hello, {{.C | html}}!", + "Hello, <Cincinnati>!", + }, + { + "overescaping2", + "Hello, {{html .C}}!", + "Hello, <Cincinnati>!", + }, + { + "overescaping3", + "{{with .C}}{{$msg := .}}Hello, {{$msg}}!{{end}}", + "Hello, <Cincinnati>!", + }, + { + "assignment", + "{{if $x := .H}}{{$x}}{{end}}", + "<Hello>", + }, + { + "withBody", + "{{with .H}}{{.}}{{end}}", + "<Hello>", + }, + { + "withElse", + "{{with .E}}{{.}}{{else}}{{.H}}{{end}}", + "<Hello>", + }, + { + "rangeBody", + "{{range .A}}{{.}}{{end}}", + "<a><b>", + }, + { + "rangeElse", + "{{range .E}}{{.}}{{else}}{{.H}}{{end}}", + "<Hello>", + }, + { + "nonStringValue", + "{{.T}}", + "true", + }, + { + "untypedNilValue", + "{{.U}}", + "", + }, + { + "typedNilValue", + "{{.Z}}", + "<nil>", + }, + { + "constant", + `<a href="/search?q={{"'a<b'"}}">`, + `<a href="/search?q=%27a%3cb%27">`, + }, + { + "multipleAttrs", + "<a b=1 c={{.H}}>", + "<a b=1 c=<Hello>>", + }, + { + "urlStartRel", + `<a href='{{"/foo/bar?a=b&c=d"}}'>`, + `<a href='/foo/bar?a=b&c=d'>`, + }, + { + "urlStartAbsOk", + `<a href='{{"http://example.com/foo/bar?a=b&c=d"}}'>`, + `<a href='http://example.com/foo/bar?a=b&c=d'>`, + }, + { + "protocolRelativeURLStart", + `<a href='{{"//example.com:8000/foo/bar?a=b&c=d"}}'>`, + `<a href='//example.com:8000/foo/bar?a=b&c=d'>`, + }, + { + "pathRelativeURLStart", + `<a href="{{"/javascript:80/foo/bar"}}">`, + `<a href="/javascript:80/foo/bar">`, + }, + { + "dangerousURLStart", + `<a href='{{"javascript:alert(%22pwned%22)"}}'>`, + `<a href='#ZgotmplZ'>`, + }, + { + "dangerousURLStart2", + `<a href=' {{"javascript:alert(%22pwned%22)"}}'>`, + `<a href=' #ZgotmplZ'>`, + }, + { + "nonHierURL", + `<a href={{"mailto:Muhammed \"The Greatest\" Ali <m.ali@example.com>"}}>`, + `<a href=mailto:Muhammed%20%22The%20Greatest%22%20Ali%20%3cm.ali@example.com%3e>`, + }, + { + "urlPath", + `<a href='http://{{"javascript:80"}}/foo'>`, + `<a href='http://javascript:80/foo'>`, + }, + { + "urlQuery", + `<a href='/search?q={{.H}}'>`, + `<a href='/search?q=%3cHello%3e'>`, + }, + { + "urlFragment", + `<a href='/faq#{{.H}}'>`, + `<a href='/faq#%3cHello%3e'>`, + }, + { + "urlBranch", + `<a href="{{if .F}}/foo?a=b{{else}}/bar{{end}}">`, + `<a href="/bar">`, + }, + { + "urlBranchConflictMoot", + `<a href="{{if .T}}/foo?a={{else}}/bar#{{end}}{{.C}}">`, + `<a href="/foo?a=%3cCincinnati%3e">`, + }, + { + "jsStrValue", + "<button onclick='alert({{.H}})'>", + `<button onclick='alert("\u003cHello\u003e")'>`, + }, + { + "jsNumericValue", + "<button onclick='alert({{.N}})'>", + `<button onclick='alert( 42 )'>`, + }, + { + "jsBoolValue", + "<button onclick='alert({{.T}})'>", + `<button onclick='alert( true )'>`, + }, + { + "jsNilValueTyped", + "<button onclick='alert(typeof{{.Z}})'>", + `<button onclick='alert(typeof null )'>`, + }, + { + "jsNilValueUntyped", + "<button onclick='alert(typeof{{.U}})'>", + `<button onclick='alert(typeof null )'>`, + }, + { + "jsObjValue", + "<button onclick='alert({{.A}})'>", + `<button onclick='alert(["\u003ca\u003e","\u003cb\u003e"])'>`, + }, + { + "jsObjValueScript", + "<script>alert({{.A}})</script>", + `<script>alert(["\u003ca\u003e","\u003cb\u003e"])</script>`, + }, + { + "jsObjValueNotOverEscaped", + "<button onclick='alert({{.A | html}})'>", + `<button onclick='alert(["\u003ca\u003e","\u003cb\u003e"])'>`, + }, + { + "jsStr", + "<button onclick='alert("{{.H}}")'>", + `<button onclick='alert("\u003cHello\u003e")'>`, + }, + { + "badMarshaler", + `<button onclick='alert(1/{{.B}}in numbers)'>`, + `<button onclick='alert(1/ /* json: error calling MarshalJSON for type *template.badMarshaler: invalid character 'f' looking for beginning of object key string */null in numbers)'>`, + }, + { + "jsMarshaler", + `<button onclick='alert({{.M}})'>`, + `<button onclick='alert({"\u003cfoo\u003e":"O'Reilly"})'>`, + }, + { + "jsStrNotUnderEscaped", + "<button onclick='alert({{.C | urlquery}})'>", + // URL escaped, then quoted for JS. + `<button onclick='alert("%3CCincinnati%3E")'>`, + }, + { + "jsRe", + `<button onclick='alert(/{{"foo+bar"}}/.test(""))'>`, + `<button onclick='alert(/foo\u002bbar/.test(""))'>`, + }, + { + "jsReBlank", + `<script>alert(/{{""}}/.test(""));</script>`, + `<script>alert(/(?:)/.test(""));</script>`, + }, + { + "jsReAmbigOk", + `<script>{{if true}}var x = 1{{end}}</script>`, + // The {if} ends in an ambiguous jsCtx but there is + // no slash following so we shouldn't care. + `<script>var x = 1</script>`, + }, + { + "styleBidiKeywordPassed", + `<p style="dir: {{"ltr"}}">`, + `<p style="dir: ltr">`, + }, + { + "styleBidiPropNamePassed", + `<p style="border-{{"left"}}: 0; border-{{"right"}}: 1in">`, + `<p style="border-left: 0; border-right: 1in">`, + }, + { + "styleExpressionBlocked", + `<p style="width: {{"expression(alert(1337))"}}">`, + `<p style="width: ZgotmplZ">`, + }, + { + "styleTagSelectorPassed", + `<style>{{"p"}} { color: pink }</style>`, + `<style>p { color: pink }</style>`, + }, + { + "styleIDPassed", + `<style>p{{"#my-ID"}} { font: Arial }</style>`, + `<style>p#my-ID { font: Arial }</style>`, + }, + { + "styleClassPassed", + `<style>p{{".my_class"}} { font: Arial }</style>`, + `<style>p.my_class { font: Arial }</style>`, + }, + { + "styleQuantityPassed", + `<a style="left: {{"2em"}}; top: {{0}}">`, + `<a style="left: 2em; top: 0">`, + }, + { + "stylePctPassed", + `<table style=width:{{"100%"}}>`, + `<table style=width:100%>`, + }, + { + "styleColorPassed", + `<p style="color: {{"#8ff"}}; background: {{"#000"}}">`, + `<p style="color: #8ff; background: #000">`, + }, + { + "styleObfuscatedExpressionBlocked", + `<p style="width: {{" e\\78preS\x00Sio/**/n(alert(1337))"}}">`, + `<p style="width: ZgotmplZ">`, + }, + { + "styleMozBindingBlocked", + `<p style="{{"-moz-binding(alert(1337))"}}: ...">`, + `<p style="ZgotmplZ: ...">`, + }, + { + "styleObfuscatedMozBindingBlocked", + `<p style="{{" -mo\\7a-B\x00I/**/nding(alert(1337))"}}: ...">`, + `<p style="ZgotmplZ: ...">`, + }, + { + "styleFontNameString", + `<p style='font-family: "{{"Times New Roman"}}"'>`, + `<p style='font-family: "Times New Roman"'>`, + }, + { + "styleFontNameString", + `<p style='font-family: "{{"Times New Roman"}}", "{{"sans-serif"}}"'>`, + `<p style='font-family: "Times New Roman", "sans-serif"'>`, + }, + { + "styleFontNameUnquoted", + `<p style='font-family: {{"Times New Roman"}}'>`, + `<p style='font-family: Times New Roman'>`, + }, + { + "styleURLQueryEncoded", + `<p style="background: url(/img?name={{"O'Reilly Animal(1)<2>.png"}})">`, + `<p style="background: url(/img?name=O%27Reilly%20Animal%281%29%3c2%3e.png)">`, + }, + { + "styleQuotedURLQueryEncoded", + `<p style="background: url('/img?name={{"O'Reilly Animal(1)<2>.png"}}')">`, + `<p style="background: url('/img?name=O%27Reilly%20Animal%281%29%3c2%3e.png')">`, + }, + { + "styleStrQueryEncoded", + `<p style="background: '/img?name={{"O'Reilly Animal(1)<2>.png"}}'">`, + `<p style="background: '/img?name=O%27Reilly%20Animal%281%29%3c2%3e.png'">`, + }, + { + "styleURLBadProtocolBlocked", + `<a style="background: url('{{"javascript:alert(1337)"}}')">`, + `<a style="background: url('#ZgotmplZ')">`, + }, + { + "styleStrBadProtocolBlocked", + `<a style="background: '{{"vbscript:alert(1337)"}}'">`, + `<a style="background: '#ZgotmplZ'">`, + }, + { + "styleStrEncodedProtocolEncoded", + `<a style="background: '{{"javascript\\3a alert(1337)"}}'">`, + // The CSS string 'javascript\\3a alert(1337)' does not contain a colon. + `<a style="background: 'javascript\\3a alert\28 1337\29 '">`, + }, + { + "styleURLGoodProtocolPassed", + `<a style="background: url('{{"http://oreilly.com/O'Reilly Animals(1)<2>;{}.html"}}')">`, + `<a style="background: url('http://oreilly.com/O%27Reilly%20Animals%281%29%3c2%3e;%7b%7d.html')">`, + }, + { + "styleStrGoodProtocolPassed", + `<a style="background: '{{"http://oreilly.com/O'Reilly Animals(1)<2>;{}.html"}}'">`, + `<a style="background: 'http\3a\2f\2foreilly.com\2fO\27Reilly Animals\28 1\29\3c 2\3e\3b\7b\7d.html'">`, + }, + { + "styleURLEncodedForHTMLInAttr", + `<a style="background: url('{{"/search?img=foo&size=icon"}}')">`, + `<a style="background: url('/search?img=foo&size=icon')">`, + }, + { + "styleURLNotEncodedForHTMLInCdata", + `<style>body { background: url('{{"/search?img=foo&size=icon"}}') }</style>`, + `<style>body { background: url('/search?img=foo&size=icon') }</style>`, + }, + { + "styleURLMixedCase", + `<p style="background: URL(#{{.H}})">`, + `<p style="background: URL(#%3cHello%3e)">`, + }, + { + "stylePropertyPairPassed", + `<a style='{{"color: red"}}'>`, + `<a style='color: red'>`, + }, + { + "styleStrSpecialsEncoded", + `<a style="font-family: '{{"/**/'\";:// \\"}}', "{{"/**/'\";:// \\"}}"">`, + `<a style="font-family: '\2f**\2f\27\22\3b\3a\2f\2f \\', "\2f**\2f\27\22\3b\3a\2f\2f \\"">`, + }, + { + "styleURLSpecialsEncoded", + `<a style="border-image: url({{"/**/'\";:// \\"}}), url("{{"/**/'\";:// \\"}}"), url('{{"/**/'\";:// \\"}}'), 'http://www.example.com/?q={{"/**/'\";:// \\"}}''">`, + `<a style="border-image: url(/**/%27%22;://%20%5c), url("/**/%27%22;://%20%5c"), url('/**/%27%22;://%20%5c'), 'http://www.example.com/?q=%2f%2a%2a%2f%27%22%3b%3a%2f%2f%20%5c''">`, + }, + { + "HTML comment", + "<b>Hello, <!-- name of world -->{{.C}}</b>", + "<b>Hello, <Cincinnati></b>", + }, + { + "HTML comment not first < in text node.", + "<<!-- -->!--", + "<!--", + }, + { + "HTML normalization 1", + "a < b", + "a < b", + }, + { + "HTML normalization 2", + "a << b", + "a << b", + }, + { + "HTML normalization 3", + "a<<!-- --><!-- -->b", + "a<b", + }, + { + "HTML doctype not normalized", + "<!DOCTYPE html>Hello, World!", + "<!DOCTYPE html>Hello, World!", + }, + { + "HTML doctype not case-insensitive", + "<!doCtYPE htMl>Hello, World!", + "<!doCtYPE htMl>Hello, World!", + }, + { + "No doctype injection", + `<!{{"DOCTYPE"}}`, + "<!DOCTYPE", + }, + { + "Split HTML comment", + "<b>Hello, <!-- name of {{if .T}}city -->{{.C}}{{else}}world -->{{.W}}{{end}}</b>", + "<b>Hello, <Cincinnati></b>", + }, + { + "JS line comment", + "<script>for (;;) { if (c()) break// foo not a label\n" + + "foo({{.T}});}</script>", + "<script>for (;;) { if (c()) break\n" + + "foo( true );}</script>", + }, + { + "JS multiline block comment", + "<script>for (;;) { if (c()) break/* foo not a label\n" + + " */foo({{.T}});}</script>", + // Newline separates break from call. If newline + // removed, then break will consume label leaving + // code invalid. + "<script>for (;;) { if (c()) break\n" + + "foo( true );}</script>", + }, + { + "JS single-line block comment", + "<script>for (;;) {\n" + + "if (c()) break/* foo a label */foo;" + + "x({{.T}});}</script>", + // Newline separates break from call. If newline + // removed, then break will consume label leaving + // code invalid. + "<script>for (;;) {\n" + + "if (c()) break foo;" + + "x( true );}</script>", + }, + { + "JS block comment flush with mathematical division", + "<script>var a/*b*//c\nd</script>", + "<script>var a /c\nd</script>", + }, + { + "JS mixed comments", + "<script>var a/*b*///c\nd</script>", + "<script>var a \nd</script>", + }, + { + "CSS comments", + "<style>p// paragraph\n" + + `{border: 1px/* color */{{"#00f"}}}</style>`, + "<style>p\n" + + "{border: 1px #00f}</style>", + }, + { + "JS attr block comment", + `<a onclick="f(""); /* alert({{.H}}) */">`, + // Attribute comment tests should pass if the comments + // are successfully elided. + `<a onclick="f(""); /* alert() */">`, + }, + { + "JS attr line comment", + `<a onclick="// alert({{.G}})">`, + `<a onclick="// alert()">`, + }, + { + "CSS attr block comment", + `<a style="/* color: {{.H}} */">`, + `<a style="/* color: */">`, + }, + { + "CSS attr line comment", + `<a style="// color: {{.G}}">`, + `<a style="// color: ">`, + }, + { + "HTML substitution commented out", + "<p><!-- {{.H}} --></p>", + "<p></p>", + }, + { + "Comment ends flush with start", + "<!--{{.}}--><script>/*{{.}}*///{{.}}\n</script><style>/*{{.}}*///{{.}}\n</style><a onclick='/*{{.}}*///{{.}}' style='/*{{.}}*///{{.}}'>", + "<script> \n</script><style> \n</style><a onclick='/**///' style='/**///'>", + }, + { + "typed HTML in text", + `{{.W}}`, + `¡<b class="foo">Hello</b>, <textarea>O'World</textarea>!`, + }, + { + "typed HTML in attribute", + `<div title="{{.W}}">`, + `<div title="¡Hello, O'World!">`, + }, + { + "typed HTML in script", + `<button onclick="alert({{.W}})">`, + `<button onclick="alert("\u0026iexcl;\u003cb class=\"foo\"\u003eHello\u003c/b\u003e, \u003ctextarea\u003eO'World\u003c/textarea\u003e!")">`, + }, + { + "typed HTML in RCDATA", + `<textarea>{{.W}}</textarea>`, + `<textarea>¡<b class="foo">Hello</b>, <textarea>O'World</textarea>!</textarea>`, + }, + { + "range in textarea", + "<textarea>{{range .A}}{{.}}{{end}}</textarea>", + "<textarea><a><b></textarea>", + }, + { + "No tag injection", + `{{"10$"}}<{{"script src,evil.org/pwnd.js"}}...`, + `10$<script src,evil.org/pwnd.js...`, + }, + { + "No comment injection", + `<{{"!--"}}`, + `<!--`, + }, + { + "No RCDATA end tag injection", + `<textarea><{{"/textarea "}}...</textarea>`, + `<textarea></textarea ...</textarea>`, + }, + { + "optional attrs", + `<img class="{{"iconClass"}}"` + + `{{if .T}} id="{{"<iconId>"}}"{{end}}` + + // Double quotes inside if/else. + ` src=` + + `{{if .T}}"?{{"<iconPath>"}}"` + + `{{else}}"images/cleardot.gif"{{end}}` + + // Missing space before title, but it is not a + // part of the src attribute. + `{{if .T}}title="{{"<title>"}}"{{end}}` + + // Quotes outside if/else. + ` alt="` + + `{{if .T}}{{"<alt>"}}` + + `{{else}}{{if .F}}{{"<title>"}}{{end}}` + + `{{end}}"` + + `>`, + `<img class="iconClass" id="<iconId>" src="?%3ciconPath%3e"title="<title>" alt="<alt>">`, + }, + { + "conditional valueless attr name", + `<input{{if .T}} checked{{end}} name=n>`, + `<input checked name=n>`, + }, + { + "conditional dynamic valueless attr name 1", + `<input{{if .T}} {{"checked"}}{{end}} name=n>`, + `<input checked name=n>`, + }, + { + "conditional dynamic valueless attr name 2", + `<input {{if .T}}{{"checked"}} {{end}}name=n>`, + `<input checked name=n>`, + }, + { + "dynamic attribute name", + `<img on{{"load"}}="alert({{"loaded"}})">`, + // Treated as JS since quotes are inserted. + `<img onload="alert("loaded")">`, + }, + { + "bad dynamic attribute name 1", + // Allow checked, selected, disabled, but not JS or + // CSS attributes. + `<input {{"onchange"}}="{{"doEvil()"}}">`, + `<input ZgotmplZ="doEvil()">`, + }, + { + "bad dynamic attribute name 2", + `<div {{"sTyle"}}="{{"color: expression(alert(1337))"}}">`, + `<div ZgotmplZ="color: expression(alert(1337))">`, + }, + { + "bad dynamic attribute name 3", + // Allow title or alt, but not a URL. + `<img {{"src"}}="{{"javascript:doEvil()"}}">`, + `<img ZgotmplZ="javascript:doEvil()">`, + }, + { + "bad dynamic attribute name 4", + // Structure preservation requires values to associate + // with a consistent attribute. + `<input checked {{""}}="Whose value am I?">`, + `<input checked ZgotmplZ="Whose value am I?">`, + }, + { + "dynamic element name", + `<h{{3}}><table><t{{"head"}}>...</h{{3}}>`, + `<h3><table><thead>...</h3>`, + }, + { + "bad dynamic element name", + // Dynamic element names are typically used to switch + // between (thead, tfoot, tbody), (ul, ol), (th, td), + // and other replaceable sets. + // We do not currently easily support (ul, ol). + // If we do change to support that, this test should + // catch failures to filter out special tag names which + // would violate the structure preservation property -- + // if any special tag name could be substituted, then + // the content could be raw text/RCDATA for some inputs + // and regular HTML content for others. + `<{{"script"}}>{{"doEvil()"}}</{{"script"}}>`, + `<script>doEvil()</script>`, + }, + { + "srcset bad URL in second position", + `<img srcset="{{"/not-an-image#,javascript:alert(1)"}}">`, + // The second URL is also filtered. + `<img srcset="/not-an-image#,#ZgotmplZ">`, + }, + { + "srcset buffer growth", + `<img srcset={{",,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,"}}>`, + `<img srcset=,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,>`, + }, + } + + for _, test := range tests { + tmpl := New(test.name) + tmpl = Must(tmpl.Parse(test.input)) + // Check for bug 6459: Tree field was not set in Parse. + if tmpl.Tree != tmpl.text.Tree { + t.Errorf("%s: tree not set properly", test.name) + continue + } + b := new(bytes.Buffer) + if err := tmpl.Execute(b, data); err != nil { + t.Errorf("%s: template execution failed: %s", test.name, err) + continue + } + if w, g := test.output, b.String(); w != g { + t.Errorf("%s: escaped output: want\n\t%q\ngot\n\t%q", test.name, w, g) + continue + } + b.Reset() + if err := tmpl.Execute(b, pdata); err != nil { + t.Errorf("%s: template execution failed for pointer: %s", test.name, err) + continue + } + if w, g := test.output, b.String(); w != g { + t.Errorf("%s: escaped output for pointer: want\n\t%q\ngot\n\t%q", test.name, w, g) + continue + } + if tmpl.Tree != tmpl.text.Tree { + t.Errorf("%s: tree mismatch", test.name) + continue + } + } +} + +func TestEscapeMap(t *testing.T) { + data := map[string]string{ + "html": `<h1>Hi!</h1>`, + "urlquery": `http://www.foo.com/index.html?title=main`, + } + for _, test := range [...]struct { + desc, input, output string + }{ + // covering issue 20323 + { + "field with predefined escaper name 1", + `{{.html | print}}`, + `<h1>Hi!</h1>`, + }, + // covering issue 20323 + { + "field with predefined escaper name 2", + `{{.urlquery | print}}`, + `http://www.foo.com/index.html?title=main`, + }, + } { + tmpl := Must(New("").Parse(test.input)) + b := new(bytes.Buffer) + if err := tmpl.Execute(b, data); err != nil { + t.Errorf("%s: template execution failed: %s", test.desc, err) + continue + } + if w, g := test.output, b.String(); w != g { + t.Errorf("%s: escaped output: want\n\t%q\ngot\n\t%q", test.desc, w, g) + continue + } + } +} + +func TestEscapeSet(t *testing.T) { + type dataItem struct { + Children []*dataItem + X string + } + + data := dataItem{ + Children: []*dataItem{ + {X: "foo"}, + {X: "<bar>"}, + { + Children: []*dataItem{ + {X: "baz"}, + }, + }, + }, + } + + tests := []struct { + inputs map[string]string + want string + }{ + // The trivial set. + { + map[string]string{ + "main": ``, + }, + ``, + }, + // A template called in the start context. + { + map[string]string{ + "main": `Hello, {{template "helper"}}!`, + // Not a valid top level HTML template. + // "<b" is not a full tag. + "helper": `{{"<World>"}}`, + }, + `Hello, <World>!`, + }, + // A template called in a context other than the start. + { + map[string]string{ + "main": `<a onclick='a = {{template "helper"}};'>`, + // Not a valid top level HTML template. + // "<b" is not a full tag. + "helper": `{{"<a>"}}<b`, + }, + `<a onclick='a = "\u003ca\u003e"<b;'>`, + }, + // A recursive template that ends in its start context. + { + map[string]string{ + "main": `{{range .Children}}{{template "main" .}}{{else}}{{.X}} {{end}}`, + }, + `foo <bar> baz `, + }, + // A recursive helper template that ends in its start context. + { + map[string]string{ + "main": `{{template "helper" .}}`, + "helper": `{{if .Children}}<ul>{{range .Children}}<li>{{template "main" .}}</li>{{end}}</ul>{{else}}{{.X}}{{end}}`, + }, + `<ul><li>foo</li><li><bar></li><li><ul><li>baz</li></ul></li></ul>`, + }, + // Co-recursive templates that end in its start context. + { + map[string]string{ + "main": `<blockquote>{{range .Children}}{{template "helper" .}}{{end}}</blockquote>`, + "helper": `{{if .Children}}{{template "main" .}}{{else}}{{.X}}<br>{{end}}`, + }, + `<blockquote>foo<br><bar><br><blockquote>baz<br></blockquote></blockquote>`, + }, + // A template that is called in two different contexts. + { + map[string]string{ + "main": `<button onclick="title='{{template "helper"}}'; ...">{{template "helper"}}</button>`, + "helper": `{{11}} of {{"<100>"}}`, + }, + `<button onclick="title='11 of \u003c100\u003e'; ...">11 of <100></button>`, + }, + // A non-recursive template that ends in a different context. + // helper starts in jsCtxRegexp and ends in jsCtxDivOp. + { + map[string]string{ + "main": `<script>var x={{template "helper"}}/{{"42"}};</script>`, + "helper": "{{126}}", + }, + `<script>var x= 126 /"42";</script>`, + }, + // A recursive template that ends in a similar context. + { + map[string]string{ + "main": `<script>var x=[{{template "countdown" 4}}];</script>`, + "countdown": `{{.}}{{if .}},{{template "countdown" . | pred}}{{end}}`, + }, + `<script>var x=[ 4 , 3 , 2 , 1 , 0 ];</script>`, + }, + // A recursive template that ends in a different context. + /* + { + map[string]string{ + "main": `<a href="/foo{{template "helper" .}}">`, + "helper": `{{if .Children}}{{range .Children}}{{template "helper" .}}{{end}}{{else}}?x={{.X}}{{end}}`, + }, + `<a href="/foo?x=foo?x=%3cbar%3e?x=baz">`, + }, + */ + } + + // pred is a template function that returns the predecessor of a + // natural number for testing recursive templates. + fns := FuncMap{"pred": func(a ...interface{}) (interface{}, error) { + if len(a) == 1 { + if i, _ := a[0].(int); i > 0 { + return i - 1, nil + } + } + return nil, fmt.Errorf("undefined pred(%v)", a) + }} + + for _, test := range tests { + source := "" + for name, body := range test.inputs { + source += fmt.Sprintf("{{define %q}}%s{{end}} ", name, body) + } + tmpl, err := New("root").Funcs(fns).Parse(source) + if err != nil { + t.Errorf("error parsing %q: %v", source, err) + continue + } + var b bytes.Buffer + + if err := tmpl.ExecuteTemplate(&b, "main", data); err != nil { + t.Errorf("%q executing %v", err.Error(), tmpl.Lookup("main")) + continue + } + if got := b.String(); test.want != got { + t.Errorf("want\n\t%q\ngot\n\t%q", test.want, got) + } + } + +} + +func TestErrors(t *testing.T) { + tests := []struct { + input string + err string + }{ + // Non-error cases. + { + "{{if .Cond}}<a>{{else}}<b>{{end}}", + "", + }, + { + "{{if .Cond}}<a>{{end}}", + "", + }, + { + "{{if .Cond}}{{else}}<b>{{end}}", + "", + }, + { + "{{with .Cond}}<div>{{end}}", + "", + }, + { + "{{range .Items}}<a>{{end}}", + "", + }, + { + "<a href='/foo?{{range .Items}}&{{.K}}={{.V}}{{end}}'>", + "", + }, + // Error cases. + { + "{{if .Cond}}<a{{end}}", + "z:1:5: {{if}} branches", + }, + { + "{{if .Cond}}\n{{else}}\n<a{{end}}", + "z:1:5: {{if}} branches", + }, + { + // Missing quote in the else branch. + `{{if .Cond}}<a href="foo">{{else}}<a href="bar>{{end}}`, + "z:1:5: {{if}} branches", + }, + { + // Different kind of attribute: href implies a URL. + "<a {{if .Cond}}href='{{else}}title='{{end}}{{.X}}'>", + "z:1:8: {{if}} branches", + }, + { + "\n{{with .X}}<a{{end}}", + "z:2:7: {{with}} branches", + }, + { + "\n{{with .X}}<a>{{else}}<a{{end}}", + "z:2:7: {{with}} branches", + }, + { + "{{range .Items}}<a{{end}}", + `z:1: on range loop re-entry: "<" in attribute name: "<a"`, + }, + { + "\n{{range .Items}} x='<a{{end}}", + "z:2:8: on range loop re-entry: {{range}} branches", + }, + { + "<a b=1 c={{.H}}", + "z: ends in a non-text context: {stateAttr delimSpaceOrTagEnd", + }, + { + "<script>foo();", + "z: ends in a non-text context: {stateJS", + }, + { + `<a href="{{if .F}}/foo?a={{else}}/bar/{{end}}{{.H}}">`, + "z:1:47: {{.H}} appears in an ambiguous context within a URL", + }, + { + `<a onclick="alert('Hello \`, + `unfinished escape sequence in JS string: "Hello \\"`, + }, + { + `<a onclick='alert("Hello\, World\`, + `unfinished escape sequence in JS string: "Hello\\, World\\"`, + }, + { + `<a onclick='alert(/x+\`, + `unfinished escape sequence in JS string: "x+\\"`, + }, + { + `<a onclick="/foo[\]/`, + `unfinished JS regexp charset: "foo[\\]/"`, + }, + { + // It is ambiguous whether 1.5 should be 1\.5 or 1.5. + // Either `var x = 1/- 1.5 /i.test(x)` + // where `i.test(x)` is a method call of reference i, + // or `/-1\.5/i.test(x)` which is a method call on a + // case insensitive regular expression. + `<script>{{if false}}var x = 1{{end}}/-{{"1.5"}}/i.test(x)</script>`, + `'/' could start a division or regexp: "/-"`, + }, + { + `{{template "foo"}}`, + "z:1:11: no such template \"foo\"", + }, + { + `<div{{template "y"}}>` + + // Illegal starting in stateTag but not in stateText. + `{{define "y"}} foo<b{{end}}`, + `"<" in attribute name: " foo<b"`, + }, + { + `<script>reverseList = [{{template "t"}}]</script>` + + // Missing " after recursive call. + `{{define "t"}}{{if .Tail}}{{template "t" .Tail}}{{end}}{{.Head}}",{{end}}`, + `: cannot compute output context for template t$htmltemplate_stateJS_elementScript`, + }, + { + `<input type=button value=onclick=>`, + `html/template:z: "=" in unquoted attr: "onclick="`, + }, + { + `<input type=button value= onclick=>`, + `html/template:z: "=" in unquoted attr: "onclick="`, + }, + { + `<input type=button value= 1+1=2>`, + `html/template:z: "=" in unquoted attr: "1+1=2"`, + }, + { + "<a class=`foo>", + "html/template:z: \"`\" in unquoted attr: \"`foo\"", + }, + { + `<a style=font:'Arial'>`, + `html/template:z: "'" in unquoted attr: "font:'Arial'"`, + }, + { + `<a=foo>`, + `: expected space, attr name, or end of tag, but got "=foo>"`, + }, + { + `Hello, {{. | urlquery | print}}!`, + // urlquery is disallowed if it is not the last command in the pipeline. + `predefined escaper "urlquery" disallowed in template`, + }, + { + `Hello, {{. | html | print}}!`, + // html is disallowed if it is not the last command in the pipeline. + `predefined escaper "html" disallowed in template`, + }, + { + `Hello, {{html . | print}}!`, + // A direct call to html is disallowed if it is not the last command in the pipeline. + `predefined escaper "html" disallowed in template`, + }, + { + `<div class={{. | html}}>Hello<div>`, + // html is disallowed in a pipeline that is in an unquoted attribute context, + // even if it is the last command in the pipeline. + `predefined escaper "html" disallowed in template`, + }, + { + `Hello, {{. | urlquery | html}}!`, + // html is allowed since it is the last command in the pipeline, but urlquery is not. + `predefined escaper "urlquery" disallowed in template`, + }, + } + for _, test := range tests { + buf := new(bytes.Buffer) + tmpl, err := New("z").Parse(test.input) + if err != nil { + t.Errorf("input=%q: unexpected parse error %s\n", test.input, err) + continue + } + err = tmpl.Execute(buf, nil) + var got string + if err != nil { + got = err.Error() + } + if test.err == "" { + if got != "" { + t.Errorf("input=%q: unexpected error %q", test.input, got) + } + continue + } + if !strings.Contains(got, test.err) { + t.Errorf("input=%q: error\n\t%q\ndoes not contain expected string\n\t%q", test.input, got, test.err) + continue + } + // Check that we get the same error if we call Execute again. + if err := tmpl.Execute(buf, nil); err == nil || err.Error() != got { + t.Errorf("input=%q: unexpected error on second call %q", test.input, err) + + } + } +} + +func TestEscapeText(t *testing.T) { + tests := []struct { + input string + output context + }{ + { + ``, + context{}, + }, + { + `Hello, World!`, + context{}, + }, + { + // An orphaned "<" is OK. + `I <3 Ponies!`, + context{}, + }, + { + `<a`, + context{state: stateTag}, + }, + { + `<a `, + context{state: stateTag}, + }, + { + `<a>`, + context{state: stateText}, + }, + { + `<a href`, + context{state: stateAttrName, attr: attrURL}, + }, + { + `<a on`, + context{state: stateAttrName, attr: attrScript}, + }, + { + `<a href `, + context{state: stateAfterName, attr: attrURL}, + }, + { + `<a style = `, + context{state: stateBeforeValue, attr: attrStyle}, + }, + { + `<a href=`, + context{state: stateBeforeValue, attr: attrURL}, + }, + { + `<a href=x`, + context{state: stateURL, delim: delimSpaceOrTagEnd, urlPart: urlPartPreQuery, attr: attrURL}, + }, + { + `<a href=x `, + context{state: stateTag}, + }, + { + `<a href=>`, + context{state: stateText}, + }, + { + `<a href=x>`, + context{state: stateText}, + }, + { + `<a href ='`, + context{state: stateURL, delim: delimSingleQuote, attr: attrURL}, + }, + { + `<a href=''`, + context{state: stateTag}, + }, + { + `<a href= "`, + context{state: stateURL, delim: delimDoubleQuote, attr: attrURL}, + }, + { + `<a href=""`, + context{state: stateTag}, + }, + { + `<a title="`, + context{state: stateAttr, delim: delimDoubleQuote}, + }, + { + `<a HREF='http:`, + context{state: stateURL, delim: delimSingleQuote, urlPart: urlPartPreQuery, attr: attrURL}, + }, + { + `<a Href='/`, + context{state: stateURL, delim: delimSingleQuote, urlPart: urlPartPreQuery, attr: attrURL}, + }, + { + `<a href='"`, + context{state: stateURL, delim: delimSingleQuote, urlPart: urlPartPreQuery, attr: attrURL}, + }, + { + `<a href="'`, + context{state: stateURL, delim: delimDoubleQuote, urlPart: urlPartPreQuery, attr: attrURL}, + }, + { + `<a href=''`, + context{state: stateURL, delim: delimSingleQuote, urlPart: urlPartPreQuery, attr: attrURL}, + }, + { + `<a href=""`, + context{state: stateURL, delim: delimDoubleQuote, urlPart: urlPartPreQuery, attr: attrURL}, + }, + { + `<a href=""`, + context{state: stateURL, delim: delimDoubleQuote, urlPart: urlPartPreQuery, attr: attrURL}, + }, + { + `<a href="`, + context{state: stateURL, delim: delimSpaceOrTagEnd, urlPart: urlPartPreQuery, attr: attrURL}, + }, + { + `<img alt="1">`, + context{state: stateText}, + }, + { + `<img alt="1>"`, + context{state: stateTag}, + }, + { + `<img alt="1>">`, + context{state: stateText}, + }, + { + `<input checked type="checkbox"`, + context{state: stateTag}, + }, + { + `<a onclick="`, + context{state: stateJS, delim: delimDoubleQuote, attr: attrScript}, + }, + { + `<a onclick="//foo`, + context{state: stateJSLineCmt, delim: delimDoubleQuote, attr: attrScript}, + }, + { + "<a onclick='//\n", + context{state: stateJS, delim: delimSingleQuote, attr: attrScript}, + }, + { + "<a onclick='//\r\n", + context{state: stateJS, delim: delimSingleQuote, attr: attrScript}, + }, + { + "<a onclick='//\u2028", + context{state: stateJS, delim: delimSingleQuote, attr: attrScript}, + }, + { + `<a onclick="/*`, + context{state: stateJSBlockCmt, delim: delimDoubleQuote, attr: attrScript}, + }, + { + `<a onclick="/*/`, + context{state: stateJSBlockCmt, delim: delimDoubleQuote, attr: attrScript}, + }, + { + `<a onclick="/**/`, + context{state: stateJS, delim: delimDoubleQuote, attr: attrScript}, + }, + { + `<a onkeypress=""`, + context{state: stateJSDqStr, delim: delimDoubleQuote, attr: attrScript}, + }, + { + `<a onclick='"foo"`, + context{state: stateJS, delim: delimSingleQuote, jsCtx: jsCtxDivOp, attr: attrScript}, + }, + { + `<a onclick='foo'`, + context{state: stateJS, delim: delimSpaceOrTagEnd, jsCtx: jsCtxDivOp, attr: attrScript}, + }, + { + `<a onclick='foo`, + context{state: stateJSSqStr, delim: delimSpaceOrTagEnd, attr: attrScript}, + }, + { + `<a onclick=""foo'`, + context{state: stateJSDqStr, delim: delimDoubleQuote, attr: attrScript}, + }, + { + `<a onclick="'foo"`, + context{state: stateJSSqStr, delim: delimDoubleQuote, attr: attrScript}, + }, + { + `<A ONCLICK="'`, + context{state: stateJSSqStr, delim: delimDoubleQuote, attr: attrScript}, + }, + { + `<a onclick="/`, + context{state: stateJSRegexp, delim: delimDoubleQuote, attr: attrScript}, + }, + { + `<a onclick="'foo'`, + context{state: stateJS, delim: delimDoubleQuote, jsCtx: jsCtxDivOp, attr: attrScript}, + }, + { + `<a onclick="'foo\'`, + context{state: stateJSSqStr, delim: delimDoubleQuote, attr: attrScript}, + }, + { + `<a onclick="'foo\'`, + context{state: stateJSSqStr, delim: delimDoubleQuote, attr: attrScript}, + }, + { + `<a onclick="/foo/`, + context{state: stateJS, delim: delimDoubleQuote, jsCtx: jsCtxDivOp, attr: attrScript}, + }, + { + `<script>/foo/ /=`, + context{state: stateJS, element: elementScript}, + }, + { + `<a onclick="1 /foo`, + context{state: stateJS, delim: delimDoubleQuote, jsCtx: jsCtxDivOp, attr: attrScript}, + }, + { + `<a onclick="1 /*c*/ /foo`, + context{state: stateJS, delim: delimDoubleQuote, jsCtx: jsCtxDivOp, attr: attrScript}, + }, + { + `<a onclick="/foo[/]`, + context{state: stateJSRegexp, delim: delimDoubleQuote, attr: attrScript}, + }, + { + `<a onclick="/foo\/`, + context{state: stateJSRegexp, delim: delimDoubleQuote, attr: attrScript}, + }, + { + `<a onclick="/foo/`, + context{state: stateJS, delim: delimDoubleQuote, jsCtx: jsCtxDivOp, attr: attrScript}, + }, + { + `<input checked style="`, + context{state: stateCSS, delim: delimDoubleQuote, attr: attrStyle}, + }, + { + `<a style="//`, + context{state: stateCSSLineCmt, delim: delimDoubleQuote, attr: attrStyle}, + }, + { + `<a style="//</script>`, + context{state: stateCSSLineCmt, delim: delimDoubleQuote, attr: attrStyle}, + }, + { + "<a style='//\n", + context{state: stateCSS, delim: delimSingleQuote, attr: attrStyle}, + }, + { + "<a style='//\r", + context{state: stateCSS, delim: delimSingleQuote, attr: attrStyle}, + }, + { + `<a style="/*`, + context{state: stateCSSBlockCmt, delim: delimDoubleQuote, attr: attrStyle}, + }, + { + `<a style="/*/`, + context{state: stateCSSBlockCmt, delim: delimDoubleQuote, attr: attrStyle}, + }, + { + `<a style="/**/`, + context{state: stateCSS, delim: delimDoubleQuote, attr: attrStyle}, + }, + { + `<a style="background: '`, + context{state: stateCSSSqStr, delim: delimDoubleQuote, attr: attrStyle}, + }, + { + `<a style="background: "`, + context{state: stateCSSDqStr, delim: delimDoubleQuote, attr: attrStyle}, + }, + { + `<a style="background: '/foo?img=`, + context{state: stateCSSSqStr, delim: delimDoubleQuote, urlPart: urlPartQueryOrFrag, attr: attrStyle}, + }, + { + `<a style="background: '/`, + context{state: stateCSSSqStr, delim: delimDoubleQuote, urlPart: urlPartPreQuery, attr: attrStyle}, + }, + { + `<a style="background: url("/`, + context{state: stateCSSDqURL, delim: delimDoubleQuote, urlPart: urlPartPreQuery, attr: attrStyle}, + }, + { + `<a style="background: url('/`, + context{state: stateCSSSqURL, delim: delimDoubleQuote, urlPart: urlPartPreQuery, attr: attrStyle}, + }, + { + `<a style="background: url('/)`, + context{state: stateCSSSqURL, delim: delimDoubleQuote, urlPart: urlPartPreQuery, attr: attrStyle}, + }, + { + `<a style="background: url('/ `, + context{state: stateCSSSqURL, delim: delimDoubleQuote, urlPart: urlPartPreQuery, attr: attrStyle}, + }, + { + `<a style="background: url(/`, + context{state: stateCSSURL, delim: delimDoubleQuote, urlPart: urlPartPreQuery, attr: attrStyle}, + }, + { + `<a style="background: url( `, + context{state: stateCSSURL, delim: delimDoubleQuote, attr: attrStyle}, + }, + { + `<a style="background: url( /image?name=`, + context{state: stateCSSURL, delim: delimDoubleQuote, urlPart: urlPartQueryOrFrag, attr: attrStyle}, + }, + { + `<a style="background: url(x)`, + context{state: stateCSS, delim: delimDoubleQuote, attr: attrStyle}, + }, + { + `<a style="background: url('x'`, + context{state: stateCSS, delim: delimDoubleQuote, attr: attrStyle}, + }, + { + `<a style="background: url( x `, + context{state: stateCSS, delim: delimDoubleQuote, attr: attrStyle}, + }, + { + `<!-- foo`, + context{state: stateHTMLCmt}, + }, + { + `<!-->`, + context{state: stateHTMLCmt}, + }, + { + `<!--->`, + context{state: stateHTMLCmt}, + }, + { + `<!-- foo -->`, + context{state: stateText}, + }, + { + `<script`, + context{state: stateTag, element: elementScript}, + }, + { + `<script `, + context{state: stateTag, element: elementScript}, + }, + { + `<script src="foo.js" `, + context{state: stateTag, element: elementScript}, + }, + { + `<script src='foo.js' `, + context{state: stateTag, element: elementScript}, + }, + { + `<script type=text/javascript `, + context{state: stateTag, element: elementScript}, + }, + { + `<script>`, + context{state: stateJS, jsCtx: jsCtxRegexp, element: elementScript}, + }, + { + `<script>foo`, + context{state: stateJS, jsCtx: jsCtxDivOp, element: elementScript}, + }, + { + `<script>foo</script>`, + context{state: stateText}, + }, + { + `<script>foo</script><!--`, + context{state: stateHTMLCmt}, + }, + { + `<script>document.write("<p>foo</p>");`, + context{state: stateJS, element: elementScript}, + }, + { + `<script>document.write("<p>foo<\/script>");`, + context{state: stateJS, element: elementScript}, + }, + { + `<script>document.write("<script>alert(1)</script>");`, + context{state: stateText}, + }, + { + `<script type="text/template">`, + context{state: stateText}, + }, + // covering issue 19968 + { + `<script type="TEXT/JAVASCRIPT">`, + context{state: stateJS, element: elementScript}, + }, + // covering issue 19965 + { + `<script TYPE="text/template">`, + context{state: stateText}, + }, + { + `<script type="notjs">`, + context{state: stateText}, + }, + { + `<Script>`, + context{state: stateJS, element: elementScript}, + }, + { + `<SCRIPT>foo`, + context{state: stateJS, jsCtx: jsCtxDivOp, element: elementScript}, + }, + { + `<textarea>value`, + context{state: stateRCDATA, element: elementTextarea}, + }, + { + `<textarea>value</TEXTAREA>`, + context{state: stateText}, + }, + { + `<textarea name=html><b`, + context{state: stateRCDATA, element: elementTextarea}, + }, + { + `<title>value`, + context{state: stateRCDATA, element: elementTitle}, + }, + { + `<style>value`, + context{state: stateCSS, element: elementStyle}, + }, + { + `<a xlink:href`, + context{state: stateAttrName, attr: attrURL}, + }, + { + `<a xmlns`, + context{state: stateAttrName, attr: attrURL}, + }, + { + `<a xmlns:foo`, + context{state: stateAttrName, attr: attrURL}, + }, + { + `<a xmlnsxyz`, + context{state: stateAttrName}, + }, + { + `<a data-url`, + context{state: stateAttrName, attr: attrURL}, + }, + { + `<a data-iconUri`, + context{state: stateAttrName, attr: attrURL}, + }, + { + `<a data-urlItem`, + context{state: stateAttrName, attr: attrURL}, + }, + { + `<a g:`, + context{state: stateAttrName}, + }, + { + `<a g:url`, + context{state: stateAttrName, attr: attrURL}, + }, + { + `<a g:iconUri`, + context{state: stateAttrName, attr: attrURL}, + }, + { + `<a g:urlItem`, + context{state: stateAttrName, attr: attrURL}, + }, + { + `<a g:value`, + context{state: stateAttrName}, + }, + { + `<a svg:style='`, + context{state: stateCSS, delim: delimSingleQuote, attr: attrStyle}, + }, + { + `<svg:font-face`, + context{state: stateTag}, + }, + { + `<svg:a svg:onclick="`, + context{state: stateJS, delim: delimDoubleQuote, attr: attrScript}, + }, + { + `<svg:a svg:onclick="x()">`, + context{}, + }, + } + + for _, test := range tests { + b, e := []byte(test.input), makeEscaper(nil) + c := e.escapeText(context{}, &parse.TextNode{NodeType: parse.NodeText, Text: b}) + if !test.output.eq(c) { + t.Errorf("input %q: want context\n\t%v\ngot\n\t%v", test.input, test.output, c) + continue + } + if test.input != string(b) { + t.Errorf("input %q: text node was modified: want %q got %q", test.input, test.input, b) + continue + } + } +} + +func TestEnsurePipelineContains(t *testing.T) { + tests := []struct { + input, output string + ids []string + }{ + { + "{{.X}}", + ".X", + []string{}, + }, + { + "{{.X | html}}", + ".X | html", + []string{}, + }, + { + "{{.X}}", + ".X | html", + []string{"html"}, + }, + { + "{{html .X}}", + "_eval_args_ .X | html | urlquery", + []string{"html", "urlquery"}, + }, + { + "{{html .X .Y .Z}}", + "_eval_args_ .X .Y .Z | html | urlquery", + []string{"html", "urlquery"}, + }, + { + "{{.X | print}}", + ".X | print | urlquery", + []string{"urlquery"}, + }, + { + "{{.X | print | urlquery}}", + ".X | print | urlquery", + []string{"urlquery"}, + }, + { + "{{.X | urlquery}}", + ".X | html | urlquery", + []string{"html", "urlquery"}, + }, + { + "{{.X | print 2 | .f 3}}", + ".X | print 2 | .f 3 | urlquery | html", + []string{"urlquery", "html"}, + }, + { + // covering issue 10801 + "{{.X | println.x }}", + ".X | println.x | urlquery | html", + []string{"urlquery", "html"}, + }, + { + // covering issue 10801 + "{{.X | (print 12 | println).x }}", + ".X | (print 12 | println).x | urlquery | html", + []string{"urlquery", "html"}, + }, + // The following test cases ensure that the merging of internal escapers + // with the predefined "html" and "urlquery" escapers is correct. + { + "{{.X | urlquery}}", + ".X | _html_template_urlfilter | urlquery", + []string{"_html_template_urlfilter", "_html_template_urlnormalizer"}, + }, + { + "{{.X | urlquery}}", + ".X | urlquery | _html_template_urlfilter | _html_template_cssescaper", + []string{"_html_template_urlfilter", "_html_template_cssescaper"}, + }, + { + "{{.X | urlquery}}", + ".X | urlquery", + []string{"_html_template_urlnormalizer"}, + }, + { + "{{.X | urlquery}}", + ".X | urlquery", + []string{"_html_template_urlescaper"}, + }, + { + "{{.X | html}}", + ".X | html", + []string{"_html_template_htmlescaper"}, + }, + { + "{{.X | html}}", + ".X | html", + []string{"_html_template_rcdataescaper"}, + }, + } + for i, test := range tests { + tmpl := template.Must(template.New("test").Parse(test.input)) + action, ok := (tmpl.Tree.Root.Nodes[0].(*parse.ActionNode)) + if !ok { + t.Errorf("First node is not an action: %s", test.input) + continue + } + pipe := action.Pipe + originalIDs := make([]string, len(test.ids)) + copy(originalIDs, test.ids) + ensurePipelineContains(pipe, test.ids) + got := pipe.String() + if got != test.output { + t.Errorf("#%d: %s, %v: want\n\t%s\ngot\n\t%s", i, test.input, originalIDs, test.output, got) + } + } +} + +func TestEscapeMalformedPipelines(t *testing.T) { + tests := []string{ + "{{ 0 | $ }}", + "{{ 0 | $ | urlquery }}", + "{{ 0 | (nil) }}", + "{{ 0 | (nil) | html }}", + } + for _, test := range tests { + var b bytes.Buffer + tmpl, err := New("test").Parse(test) + if err != nil { + t.Errorf("failed to parse set: %q", err) + } + err = tmpl.Execute(&b, nil) + if err == nil { + t.Errorf("Expected error for %q", test) + } + } +} + +func TestEscapeErrorsNotIgnorable(t *testing.T) { + var b bytes.Buffer + tmpl, _ := New("dangerous").Parse("<a") + err := tmpl.Execute(&b, nil) + if err == nil { + t.Errorf("Expected error") + } else if b.Len() != 0 { + t.Errorf("Emitted output despite escaping failure") + } +} + +func TestEscapeSetErrorsNotIgnorable(t *testing.T) { + var b bytes.Buffer + tmpl, err := New("root").Parse(`{{define "t"}}<a{{end}}`) + if err != nil { + t.Errorf("failed to parse set: %q", err) + } + err = tmpl.ExecuteTemplate(&b, "t", nil) + if err == nil { + t.Errorf("Expected error") + } else if b.Len() != 0 { + t.Errorf("Emitted output despite escaping failure") + } +} + +func TestRedundantFuncs(t *testing.T) { + inputs := []interface{}{ + "\x00\x01\x02\x03\x04\x05\x06\x07\x08\t\n\x0b\x0c\r\x0e\x0f" + + "\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f" + + ` !"#$%&'()*+,-./` + + `0123456789:;<=>?` + + `@ABCDEFGHIJKLMNO` + + `PQRSTUVWXYZ[\]^_` + + "`abcdefghijklmno" + + "pqrstuvwxyz{|}~\x7f" + + "\u00A0\u0100\u2028\u2029\ufeff\ufdec\ufffd\uffff\U0001D11E" + + "&%22\\", + CSS(`a[href =~ "//example.com"]#foo`), + HTML(`Hello, <b>World</b> &tc!`), + HTMLAttr(` dir="ltr"`), + JS(`c && alert("Hello, World!");`), + JSStr(`Hello, World & O'Reilly\x21`), + URL(`greeting=H%69&addressee=(World)`), + } + + for n0, m := range redundantFuncs { + f0 := funcMap[n0].(func(...interface{}) string) + for n1 := range m { + f1 := funcMap[n1].(func(...interface{}) string) + for _, input := range inputs { + want := f0(input) + if got := f1(want); want != got { + t.Errorf("%s %s with %T %q: want\n\t%q,\ngot\n\t%q", n0, n1, input, input, want, got) + } + } + } + } +} + +func TestIndirectPrint(t *testing.T) { + a := 3 + ap := &a + b := "hello" + bp := &b + bpp := &bp + tmpl := Must(New("t").Parse(`{{.}}`)) + var buf bytes.Buffer + err := tmpl.Execute(&buf, ap) + if err != nil { + t.Errorf("Unexpected error: %s", err) + } else if buf.String() != "3" { + t.Errorf(`Expected "3"; got %q`, buf.String()) + } + buf.Reset() + err = tmpl.Execute(&buf, bpp) + if err != nil { + t.Errorf("Unexpected error: %s", err) + } else if buf.String() != "hello" { + t.Errorf(`Expected "hello"; got %q`, buf.String()) + } +} + +// This is a test for issue 3272. +func TestEmptyTemplateHTML(t *testing.T) { + page := Must(New("page").ParseFiles(os.DevNull)) + if err := page.ExecuteTemplate(os.Stdout, "page", "nothing"); err == nil { + t.Fatal("expected error") + } +} + +type Issue7379 int + +func (Issue7379) SomeMethod(x int) string { + return fmt.Sprintf("<%d>", x) +} + +// This is a test for issue 7379: type assertion error caused panic, and then +// the code to handle the panic breaks escaping. It's hard to see the second +// problem once the first is fixed, but its fix is trivial so we let that go. See +// the discussion for issue 7379. +func TestPipeToMethodIsEscaped(t *testing.T) { + tmpl := Must(New("x").Parse("<html>{{0 | .SomeMethod}}</html>\n")) + tryExec := func() string { + defer func() { + panicValue := recover() + if panicValue != nil { + t.Errorf("panicked: %v\n", panicValue) + } + }() + var b bytes.Buffer + tmpl.Execute(&b, Issue7379(0)) + return b.String() + } + for i := 0; i < 3; i++ { + str := tryExec() + const expect = "<html><0></html>\n" + if str != expect { + t.Errorf("expected %q got %q", expect, str) + } + } +} + +// Unlike text/template, html/template crashed if given an incomplete +// template, that is, a template that had been named but not given any content. +// This is issue #10204. +func TestErrorOnUndefined(t *testing.T) { + tmpl := New("undefined") + + err := tmpl.Execute(nil, nil) + if err == nil { + t.Error("expected error") + } else if !strings.Contains(err.Error(), "incomplete") { + t.Errorf("expected error about incomplete template; got %s", err) + } +} + +// This covers issue #20842. +func TestIdempotentExecute(t *testing.T) { + tmpl := Must(New(""). + Parse(`{{define "main"}}<body>{{template "hello"}}</body>{{end}}`)) + Must(tmpl. + Parse(`{{define "hello"}}Hello, {{"Ladies & Gentlemen!"}}{{end}}`)) + got := new(bytes.Buffer) + var err error + // Ensure that "hello" produces the same output when executed twice. + want := "Hello, Ladies & Gentlemen!" + for i := 0; i < 2; i++ { + err = tmpl.ExecuteTemplate(got, "hello", nil) + if err != nil { + t.Errorf("unexpected error: %s", err) + } + if got.String() != want { + t.Errorf("after executing template \"hello\", got:\n\t%q\nwant:\n\t%q\n", got.String(), want) + } + got.Reset() + } + // Ensure that the implicit re-execution of "hello" during the execution of + // "main" does not cause the output of "hello" to change. + err = tmpl.ExecuteTemplate(got, "main", nil) + if err != nil { + t.Errorf("unexpected error: %s", err) + } + // If the HTML escaper is added again to the action {{"Ladies & Gentlemen!"}}, + // we would expected to see the ampersand overescaped to "&amp;". + want = "<body>Hello, Ladies & Gentlemen!</body>" + if got.String() != want { + t.Errorf("after executing template \"main\", got:\n\t%q\nwant:\n\t%q\n", got.String(), want) + } +} + +func BenchmarkEscapedExecute(b *testing.B) { + tmpl := Must(New("t").Parse(`<a onclick="alert('{{.}}')">{{.}}</a>`)) + var buf bytes.Buffer + b.ResetTimer() + for i := 0; i < b.N; i++ { + tmpl.Execute(&buf, "foo & 'bar' & baz") + buf.Reset() + } +} + +// Covers issue 22780. +func TestOrphanedTemplate(t *testing.T) { + t1 := Must(New("foo").Parse(`<a href="{{.}}">link1</a>`)) + t2 := Must(t1.New("foo").Parse(`bar`)) + + var b bytes.Buffer + const wantError = `template: "foo" is an incomplete or empty template` + if err := t1.Execute(&b, "javascript:alert(1)"); err == nil { + t.Fatal("expected error executing t1") + } else if gotError := err.Error(); gotError != wantError { + t.Fatalf("got t1 execution error:\n\t%s\nwant:\n\t%s", gotError, wantError) + } + b.Reset() + if err := t2.Execute(&b, nil); err != nil { + t.Fatalf("error executing t2: %s", err) + } + const want = "bar" + if got := b.String(); got != want { + t.Fatalf("t2 rendered %q, want %q", got, want) + } +} + +// Covers issue 21844. +func TestAliasedParseTreeDoesNotOverescape(t *testing.T) { + const ( + tmplText = `{{.}}` + data = `<baz>` + want = `<baz>` + ) + // Templates "foo" and "bar" both alias the same underlying parse tree. + tpl := Must(New("foo").Parse(tmplText)) + if _, err := tpl.AddParseTree("bar", tpl.Tree); err != nil { + t.Fatalf("AddParseTree error: %v", err) + } + var b1, b2 bytes.Buffer + if err := tpl.ExecuteTemplate(&b1, "foo", data); err != nil { + t.Fatalf(`ExecuteTemplate failed for "foo": %v`, err) + } + if err := tpl.ExecuteTemplate(&b2, "bar", data); err != nil { + t.Fatalf(`ExecuteTemplate failed for "foo": %v`, err) + } + got1, got2 := b1.String(), b2.String() + if got1 != want { + t.Fatalf(`Template "foo" rendered %q, want %q`, got1, want) + } + if got1 != got2 { + t.Fatalf(`Template "foo" and "bar" rendered %q and %q respectively, expected equal values`, got1, got2) + } +} diff --git a/src/html/template/example_test.go b/src/html/template/example_test.go new file mode 100644 index 0000000..6cf936f --- /dev/null +++ b/src/html/template/example_test.go @@ -0,0 +1,181 @@ +// Copyright 2015 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package template_test + +import ( + "fmt" + "html/template" + "log" + "os" + "strings" +) + +func Example() { + const tpl = ` +<!DOCTYPE html> +<html> + <head> + <meta charset="UTF-8"> + <title>{{.Title}}</title> + </head> + <body> + {{range .Items}}<div>{{ . }}</div>{{else}}<div><strong>no rows</strong></div>{{end}} + </body> +</html>` + + check := func(err error) { + if err != nil { + log.Fatal(err) + } + } + t, err := template.New("webpage").Parse(tpl) + check(err) + + data := struct { + Title string + Items []string + }{ + Title: "My page", + Items: []string{ + "My photos", + "My blog", + }, + } + + err = t.Execute(os.Stdout, data) + check(err) + + noItems := struct { + Title string + Items []string + }{ + Title: "My another page", + Items: []string{}, + } + + err = t.Execute(os.Stdout, noItems) + check(err) + + // Output: + // <!DOCTYPE html> + // <html> + // <head> + // <meta charset="UTF-8"> + // <title>My page</title> + // </head> + // <body> + // <div>My photos</div><div>My blog</div> + // </body> + // </html> + // <!DOCTYPE html> + // <html> + // <head> + // <meta charset="UTF-8"> + // <title>My another page</title> + // </head> + // <body> + // <div><strong>no rows</strong></div> + // </body> + // </html> + +} + +func Example_autoescaping() { + check := func(err error) { + if err != nil { + log.Fatal(err) + } + } + t, err := template.New("foo").Parse(`{{define "T"}}Hello, {{.}}!{{end}}`) + check(err) + err = t.ExecuteTemplate(os.Stdout, "T", "<script>alert('you have been pwned')</script>") + check(err) + // Output: + // Hello, <script>alert('you have been pwned')</script>! +} + +func Example_escape() { + const s = `"Fran & Freddie's Diner" <tasty@example.com>` + v := []interface{}{`"Fran & Freddie's Diner"`, ' ', `<tasty@example.com>`} + + fmt.Println(template.HTMLEscapeString(s)) + template.HTMLEscape(os.Stdout, []byte(s)) + fmt.Fprintln(os.Stdout, "") + fmt.Println(template.HTMLEscaper(v...)) + + fmt.Println(template.JSEscapeString(s)) + template.JSEscape(os.Stdout, []byte(s)) + fmt.Fprintln(os.Stdout, "") + fmt.Println(template.JSEscaper(v...)) + + fmt.Println(template.URLQueryEscaper(v...)) + + // Output: + // "Fran & Freddie's Diner" <tasty@example.com> + // "Fran & Freddie's Diner" <tasty@example.com> + // "Fran & Freddie's Diner"32<tasty@example.com> + // \"Fran \u0026 Freddie\'s Diner\" \u003Ctasty@example.com\u003E + // \"Fran \u0026 Freddie\'s Diner\" \u003Ctasty@example.com\u003E + // \"Fran \u0026 Freddie\'s Diner\"32\u003Ctasty@example.com\u003E + // %22Fran+%26+Freddie%27s+Diner%2232%3Ctasty%40example.com%3E + +} + +func ExampleTemplate_Delims() { + const text = "<<.Greeting>> {{.Name}}" + + data := struct { + Greeting string + Name string + }{ + Greeting: "Hello", + Name: "Joe", + } + + t := template.Must(template.New("tpl").Delims("<<", ">>").Parse(text)) + + err := t.Execute(os.Stdout, data) + if err != nil { + log.Fatal(err) + } + + // Output: + // Hello {{.Name}} +} + +// The following example is duplicated in text/template; keep them in sync. + +func ExampleTemplate_block() { + const ( + master = `Names:{{block "list" .}}{{"\n"}}{{range .}}{{println "-" .}}{{end}}{{end}}` + overlay = `{{define "list"}} {{join . ", "}}{{end}} ` + ) + var ( + funcs = template.FuncMap{"join": strings.Join} + guardians = []string{"Gamora", "Groot", "Nebula", "Rocket", "Star-Lord"} + ) + masterTmpl, err := template.New("master").Funcs(funcs).Parse(master) + if err != nil { + log.Fatal(err) + } + overlayTmpl, err := template.Must(masterTmpl.Clone()).Parse(overlay) + if err != nil { + log.Fatal(err) + } + if err := masterTmpl.Execute(os.Stdout, guardians); err != nil { + log.Fatal(err) + } + if err := overlayTmpl.Execute(os.Stdout, guardians); err != nil { + log.Fatal(err) + } + // Output: + // Names: + // - Gamora + // - Groot + // - Nebula + // - Rocket + // - Star-Lord + // Names: Gamora, Groot, Nebula, Rocket, Star-Lord +} diff --git a/src/html/template/examplefiles_test.go b/src/html/template/examplefiles_test.go new file mode 100644 index 0000000..5eb2597 --- /dev/null +++ b/src/html/template/examplefiles_test.go @@ -0,0 +1,225 @@ +// Copyright 2016 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package template_test + +import ( + "io" + "log" + "os" + "path/filepath" + "text/template" +) + +// templateFile defines the contents of a template to be stored in a file, for testing. +type templateFile struct { + name string + contents string +} + +func createTestDir(files []templateFile) string { + dir, err := os.MkdirTemp("", "template") + if err != nil { + log.Fatal(err) + } + for _, file := range files { + f, err := os.Create(filepath.Join(dir, file.name)) + if err != nil { + log.Fatal(err) + } + defer f.Close() + _, err = io.WriteString(f, file.contents) + if err != nil { + log.Fatal(err) + } + } + return dir +} + +// The following example is duplicated in text/template; keep them in sync. + +// Here we demonstrate loading a set of templates from a directory. +func ExampleTemplate_glob() { + // Here we create a temporary directory and populate it with our sample + // template definition files; usually the template files would already + // exist in some location known to the program. + dir := createTestDir([]templateFile{ + // T0.tmpl is a plain template file that just invokes T1. + {"T0.tmpl", `T0 invokes T1: ({{template "T1"}})`}, + // T1.tmpl defines a template, T1 that invokes T2. + {"T1.tmpl", `{{define "T1"}}T1 invokes T2: ({{template "T2"}}){{end}}`}, + // T2.tmpl defines a template T2. + {"T2.tmpl", `{{define "T2"}}This is T2{{end}}`}, + }) + // Clean up after the test; another quirk of running as an example. + defer os.RemoveAll(dir) + + // pattern is the glob pattern used to find all the template files. + pattern := filepath.Join(dir, "*.tmpl") + + // Here starts the example proper. + // T0.tmpl is the first name matched, so it becomes the starting template, + // the value returned by ParseGlob. + tmpl := template.Must(template.ParseGlob(pattern)) + + err := tmpl.Execute(os.Stdout, nil) + if err != nil { + log.Fatalf("template execution: %s", err) + } + // Output: + // T0 invokes T1: (T1 invokes T2: (This is T2)) +} + +// Here we demonstrate loading a set of templates from files in different directories +func ExampleTemplate_parsefiles() { + // Here we create different temporary directories and populate them with our sample + // template definition files; usually the template files would already + // exist in some location known to the program. + dir1 := createTestDir([]templateFile{ + // T1.tmpl is a plain template file that just invokes T2. + {"T1.tmpl", `T1 invokes T2: ({{template "T2"}})`}, + }) + + dir2 := createTestDir([]templateFile{ + // T2.tmpl defines a template T2. + {"T2.tmpl", `{{define "T2"}}This is T2{{end}}`}, + }) + + // Clean up after the test; another quirk of running as an example. + defer func(dirs ...string) { + for _, dir := range dirs { + os.RemoveAll(dir) + } + }(dir1, dir2) + + // Here starts the example proper. + // Let's just parse only dir1/T0 and dir2/T2 + paths := []string{ + filepath.Join(dir1, "T1.tmpl"), + filepath.Join(dir2, "T2.tmpl"), + } + tmpl := template.Must(template.ParseFiles(paths...)) + + err := tmpl.Execute(os.Stdout, nil) + if err != nil { + log.Fatalf("template execution: %s", err) + } + // Output: + // T1 invokes T2: (This is T2) +} + +// The following example is duplicated in text/template; keep them in sync. + +// This example demonstrates one way to share some templates +// and use them in different contexts. In this variant we add multiple driver +// templates by hand to an existing bundle of templates. +func ExampleTemplate_helpers() { + // Here we create a temporary directory and populate it with our sample + // template definition files; usually the template files would already + // exist in some location known to the program. + dir := createTestDir([]templateFile{ + // T1.tmpl defines a template, T1 that invokes T2. + {"T1.tmpl", `{{define "T1"}}T1 invokes T2: ({{template "T2"}}){{end}}`}, + // T2.tmpl defines a template T2. + {"T2.tmpl", `{{define "T2"}}This is T2{{end}}`}, + }) + // Clean up after the test; another quirk of running as an example. + defer os.RemoveAll(dir) + + // pattern is the glob pattern used to find all the template files. + pattern := filepath.Join(dir, "*.tmpl") + + // Here starts the example proper. + // Load the helpers. + templates := template.Must(template.ParseGlob(pattern)) + // Add one driver template to the bunch; we do this with an explicit template definition. + _, err := templates.Parse("{{define `driver1`}}Driver 1 calls T1: ({{template `T1`}})\n{{end}}") + if err != nil { + log.Fatal("parsing driver1: ", err) + } + // Add another driver template. + _, err = templates.Parse("{{define `driver2`}}Driver 2 calls T2: ({{template `T2`}})\n{{end}}") + if err != nil { + log.Fatal("parsing driver2: ", err) + } + // We load all the templates before execution. This package does not require + // that behavior but html/template's escaping does, so it's a good habit. + err = templates.ExecuteTemplate(os.Stdout, "driver1", nil) + if err != nil { + log.Fatalf("driver1 execution: %s", err) + } + err = templates.ExecuteTemplate(os.Stdout, "driver2", nil) + if err != nil { + log.Fatalf("driver2 execution: %s", err) + } + // Output: + // Driver 1 calls T1: (T1 invokes T2: (This is T2)) + // Driver 2 calls T2: (This is T2) +} + +// The following example is duplicated in text/template; keep them in sync. + +// This example demonstrates how to use one group of driver +// templates with distinct sets of helper templates. +func ExampleTemplate_share() { + // Here we create a temporary directory and populate it with our sample + // template definition files; usually the template files would already + // exist in some location known to the program. + dir := createTestDir([]templateFile{ + // T0.tmpl is a plain template file that just invokes T1. + {"T0.tmpl", "T0 ({{.}} version) invokes T1: ({{template `T1`}})\n"}, + // T1.tmpl defines a template, T1 that invokes T2. Note T2 is not defined + {"T1.tmpl", `{{define "T1"}}T1 invokes T2: ({{template "T2"}}){{end}}`}, + }) + // Clean up after the test; another quirk of running as an example. + defer os.RemoveAll(dir) + + // pattern is the glob pattern used to find all the template files. + pattern := filepath.Join(dir, "*.tmpl") + + // Here starts the example proper. + // Load the drivers. + drivers := template.Must(template.ParseGlob(pattern)) + + // We must define an implementation of the T2 template. First we clone + // the drivers, then add a definition of T2 to the template name space. + + // 1. Clone the helper set to create a new name space from which to run them. + first, err := drivers.Clone() + if err != nil { + log.Fatal("cloning helpers: ", err) + } + // 2. Define T2, version A, and parse it. + _, err = first.Parse("{{define `T2`}}T2, version A{{end}}") + if err != nil { + log.Fatal("parsing T2: ", err) + } + + // Now repeat the whole thing, using a different version of T2. + // 1. Clone the drivers. + second, err := drivers.Clone() + if err != nil { + log.Fatal("cloning drivers: ", err) + } + // 2. Define T2, version B, and parse it. + _, err = second.Parse("{{define `T2`}}T2, version B{{end}}") + if err != nil { + log.Fatal("parsing T2: ", err) + } + + // Execute the templates in the reverse order to verify the + // first is unaffected by the second. + err = second.ExecuteTemplate(os.Stdout, "T0.tmpl", "second") + if err != nil { + log.Fatalf("second execution: %s", err) + } + err = first.ExecuteTemplate(os.Stdout, "T0.tmpl", "first") + if err != nil { + log.Fatalf("first: execution: %s", err) + } + + // Output: + // T0 (second version) invokes T1: (T1 invokes T2: (T2, version B)) + // T0 (first version) invokes T1: (T1 invokes T2: (T2, version A)) +} diff --git a/src/html/template/exec_test.go b/src/html/template/exec_test.go new file mode 100644 index 0000000..8885873 --- /dev/null +++ b/src/html/template/exec_test.go @@ -0,0 +1,1831 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// Tests for template execution, copied from text/template. + +package template + +import ( + "bytes" + "errors" + "flag" + "fmt" + "io" + "reflect" + "strings" + "sync" + "testing" + "text/template" +) + +var debug = flag.Bool("debug", false, "show the errors produced by the tests") + +// T has lots of interesting pieces to use to test execution. +type T struct { + // Basics + True bool + I int + U16 uint16 + X, S string + FloatZero float64 + ComplexZero complex128 + // Nested structs. + U *U + // Struct with String method. + V0 V + V1, V2 *V + // Struct with Error method. + W0 W + W1, W2 *W + // Slices + SI []int + SICap []int + SIEmpty []int + SB []bool + // Arrays + AI [3]int + // Maps + MSI map[string]int + MSIone map[string]int // one element, for deterministic output + MSIEmpty map[string]int + MXI map[interface{}]int + MII map[int]int + MI32S map[int32]string + MI64S map[int64]string + MUI32S map[uint32]string + MUI64S map[uint64]string + MI8S map[int8]string + MUI8S map[uint8]string + SMSI []map[string]int + // Empty interfaces; used to see if we can dig inside one. + Empty0 interface{} // nil + Empty1 interface{} + Empty2 interface{} + Empty3 interface{} + Empty4 interface{} + // Non-empty interfaces. + NonEmptyInterface I + NonEmptyInterfacePtS *I + NonEmptyInterfaceNil I + NonEmptyInterfaceTypedNil I + // Stringer. + Str fmt.Stringer + Err error + // Pointers + PI *int + PS *string + PSI *[]int + NIL *int + // Function (not method) + BinaryFunc func(string, string) string + VariadicFunc func(...string) string + VariadicFuncInt func(int, ...string) string + NilOKFunc func(*int) bool + ErrFunc func() (string, error) + PanicFunc func() string + // Template to test evaluation of templates. + Tmpl *Template + // Unexported field; cannot be accessed by template. + unexported int +} + +type S []string + +func (S) Method0() string { + return "M0" +} + +type U struct { + V string +} + +type V struct { + j int +} + +func (v *V) String() string { + if v == nil { + return "nilV" + } + return fmt.Sprintf("<%d>", v.j) +} + +type W struct { + k int +} + +func (w *W) Error() string { + if w == nil { + return "nilW" + } + return fmt.Sprintf("[%d]", w.k) +} + +var siVal = I(S{"a", "b"}) + +var tVal = &T{ + True: true, + I: 17, + U16: 16, + X: "x", + S: "xyz", + U: &U{"v"}, + V0: V{6666}, + V1: &V{7777}, // leave V2 as nil + W0: W{888}, + W1: &W{999}, // leave W2 as nil + SI: []int{3, 4, 5}, + SICap: make([]int, 5, 10), + AI: [3]int{3, 4, 5}, + SB: []bool{true, false}, + MSI: map[string]int{"one": 1, "two": 2, "three": 3}, + MSIone: map[string]int{"one": 1}, + MXI: map[interface{}]int{"one": 1}, + MII: map[int]int{1: 1}, + MI32S: map[int32]string{1: "one", 2: "two"}, + MI64S: map[int64]string{2: "i642", 3: "i643"}, + MUI32S: map[uint32]string{2: "u322", 3: "u323"}, + MUI64S: map[uint64]string{2: "ui642", 3: "ui643"}, + MI8S: map[int8]string{2: "i82", 3: "i83"}, + MUI8S: map[uint8]string{2: "u82", 3: "u83"}, + SMSI: []map[string]int{ + {"one": 1, "two": 2}, + {"eleven": 11, "twelve": 12}, + }, + Empty1: 3, + Empty2: "empty2", + Empty3: []int{7, 8}, + Empty4: &U{"UinEmpty"}, + NonEmptyInterface: &T{X: "x"}, + NonEmptyInterfacePtS: &siVal, + NonEmptyInterfaceTypedNil: (*T)(nil), + Str: bytes.NewBuffer([]byte("foozle")), + Err: errors.New("erroozle"), + PI: newInt(23), + PS: newString("a string"), + PSI: newIntSlice(21, 22, 23), + BinaryFunc: func(a, b string) string { return fmt.Sprintf("[%s=%s]", a, b) }, + VariadicFunc: func(s ...string) string { return fmt.Sprint("<", strings.Join(s, "+"), ">") }, + VariadicFuncInt: func(a int, s ...string) string { return fmt.Sprint(a, "=<", strings.Join(s, "+"), ">") }, + NilOKFunc: func(s *int) bool { return s == nil }, + ErrFunc: func() (string, error) { return "bla", nil }, + PanicFunc: func() string { panic("test panic") }, + Tmpl: Must(New("x").Parse("test template")), // "x" is the value of .X +} + +var tSliceOfNil = []*T{nil} + +// A non-empty interface. +type I interface { + Method0() string +} + +var iVal I = tVal + +// Helpers for creation. +func newInt(n int) *int { + return &n +} + +func newString(s string) *string { + return &s +} + +func newIntSlice(n ...int) *[]int { + p := new([]int) + *p = make([]int, len(n)) + copy(*p, n) + return p +} + +// Simple methods with and without arguments. +func (t *T) Method0() string { + return "M0" +} + +func (t *T) Method1(a int) int { + return a +} + +func (t *T) Method2(a uint16, b string) string { + return fmt.Sprintf("Method2: %d %s", a, b) +} + +func (t *T) Method3(v interface{}) string { + return fmt.Sprintf("Method3: %v", v) +} + +func (t *T) Copy() *T { + n := new(T) + *n = *t + return n +} + +func (t *T) MAdd(a int, b []int) []int { + v := make([]int, len(b)) + for i, x := range b { + v[i] = x + a + } + return v +} + +var myError = errors.New("my error") + +// MyError returns a value and an error according to its argument. +func (t *T) MyError(error bool) (bool, error) { + if error { + return true, myError + } + return false, nil +} + +// A few methods to test chaining. +func (t *T) GetU() *U { + return t.U +} + +func (u *U) TrueFalse(b bool) string { + if b { + return "true" + } + return "" +} + +func typeOf(arg interface{}) string { + return fmt.Sprintf("%T", arg) +} + +type execTest struct { + name string + input string + output string + data interface{} + ok bool +} + +// bigInt and bigUint are hex string representing numbers either side +// of the max int boundary. +// We do it this way so the test doesn't depend on ints being 32 bits. +var ( + bigInt = fmt.Sprintf("0x%x", int(1<<uint(reflect.TypeOf(0).Bits()-1)-1)) + bigUint = fmt.Sprintf("0x%x", uint(1<<uint(reflect.TypeOf(0).Bits()-1))) +) + +var execTests = []execTest{ + // Trivial cases. + {"empty", "", "", nil, true}, + {"text", "some text", "some text", nil, true}, + {"nil action", "{{nil}}", "", nil, false}, + + // Ideal constants. + {"ideal int", "{{typeOf 3}}", "int", 0, true}, + {"ideal float", "{{typeOf 1.0}}", "float64", 0, true}, + {"ideal exp float", "{{typeOf 1e1}}", "float64", 0, true}, + {"ideal complex", "{{typeOf 1i}}", "complex128", 0, true}, + {"ideal int", "{{typeOf " + bigInt + "}}", "int", 0, true}, + {"ideal too big", "{{typeOf " + bigUint + "}}", "", 0, false}, + {"ideal nil without type", "{{nil}}", "", 0, false}, + + // Fields of structs. + {".X", "-{{.X}}-", "-x-", tVal, true}, + {".U.V", "-{{.U.V}}-", "-v-", tVal, true}, + {".unexported", "{{.unexported}}", "", tVal, false}, + + // Fields on maps. + {"map .one", "{{.MSI.one}}", "1", tVal, true}, + {"map .two", "{{.MSI.two}}", "2", tVal, true}, + {"map .NO", "{{.MSI.NO}}", "", tVal, true}, // NOTE: <no value> in text/template + {"map .one interface", "{{.MXI.one}}", "1", tVal, true}, + {"map .WRONG args", "{{.MSI.one 1}}", "", tVal, false}, + {"map .WRONG type", "{{.MII.one}}", "", tVal, false}, + + // Dots of all kinds to test basic evaluation. + {"dot int", "<{{.}}>", "<13>", 13, true}, + {"dot uint", "<{{.}}>", "<14>", uint(14), true}, + {"dot float", "<{{.}}>", "<15.1>", 15.1, true}, + {"dot bool", "<{{.}}>", "<true>", true, true}, + {"dot complex", "<{{.}}>", "<(16.2-17i)>", 16.2 - 17i, true}, + {"dot string", "<{{.}}>", "<hello>", "hello", true}, + {"dot slice", "<{{.}}>", "<[-1 -2 -3]>", []int{-1, -2, -3}, true}, + {"dot map", "<{{.}}>", "<map[two:22]>", map[string]int{"two": 22}, true}, + {"dot struct", "<{{.}}>", "<{7 seven}>", struct { + a int + b string + }{7, "seven"}, true}, + + // Variables. + {"$ int", "{{$}}", "123", 123, true}, + {"$.I", "{{$.I}}", "17", tVal, true}, + {"$.U.V", "{{$.U.V}}", "v", tVal, true}, + {"declare in action", "{{$x := $.U.V}}{{$x}}", "v", tVal, true}, + {"simple assignment", "{{$x := 2}}{{$x = 3}}{{$x}}", "3", tVal, true}, + {"nested assignment", + "{{$x := 2}}{{if true}}{{$x = 3}}{{end}}{{$x}}", + "3", tVal, true}, + {"nested assignment changes the last declaration", + "{{$x := 1}}{{if true}}{{$x := 2}}{{if true}}{{$x = 3}}{{end}}{{end}}{{$x}}", + "1", tVal, true}, + + // Type with String method. + {"V{6666}.String()", "-{{.V0}}-", "-{6666}-", tVal, true}, // NOTE: -<6666>- in text/template + {"&V{7777}.String()", "-{{.V1}}-", "-<7777>-", tVal, true}, + {"(*V)(nil).String()", "-{{.V2}}-", "-nilV-", tVal, true}, + + // Type with Error method. + {"W{888}.Error()", "-{{.W0}}-", "-{888}-", tVal, true}, // NOTE: -[888] in text/template + {"&W{999}.Error()", "-{{.W1}}-", "-[999]-", tVal, true}, + {"(*W)(nil).Error()", "-{{.W2}}-", "-nilW-", tVal, true}, + + // Pointers. + {"*int", "{{.PI}}", "23", tVal, true}, + {"*string", "{{.PS}}", "a string", tVal, true}, + {"*[]int", "{{.PSI}}", "[21 22 23]", tVal, true}, + {"*[]int[1]", "{{index .PSI 1}}", "22", tVal, true}, + {"NIL", "{{.NIL}}", "<nil>", tVal, true}, + + // Empty interfaces holding values. + {"empty nil", "{{.Empty0}}", "", tVal, true}, // NOTE: <no value> in text/template + {"empty with int", "{{.Empty1}}", "3", tVal, true}, + {"empty with string", "{{.Empty2}}", "empty2", tVal, true}, + {"empty with slice", "{{.Empty3}}", "[7 8]", tVal, true}, + {"empty with struct", "{{.Empty4}}", "{UinEmpty}", tVal, true}, + {"empty with struct, field", "{{.Empty4.V}}", "UinEmpty", tVal, true}, + + // Edge cases with <no value> with an interface value + {"field on interface", "{{.foo}}", "", nil, true}, // NOTE: <no value> in text/template + {"field on parenthesized interface", "{{(.).foo}}", "", nil, true}, // NOTE: <no value> in text/template + + // Issue 31810: Parenthesized first element of pipeline with arguments. + // See also TestIssue31810. + {"unparenthesized non-function", "{{1 2}}", "", nil, false}, + {"parenthesized non-function", "{{(1) 2}}", "", nil, false}, + {"parenthesized non-function with no args", "{{(1)}}", "1", nil, true}, // This is fine. + + // Method calls. + {".Method0", "-{{.Method0}}-", "-M0-", tVal, true}, + {".Method1(1234)", "-{{.Method1 1234}}-", "-1234-", tVal, true}, + {".Method1(.I)", "-{{.Method1 .I}}-", "-17-", tVal, true}, + {".Method2(3, .X)", "-{{.Method2 3 .X}}-", "-Method2: 3 x-", tVal, true}, + {".Method2(.U16, `str`)", "-{{.Method2 .U16 `str`}}-", "-Method2: 16 str-", tVal, true}, + {".Method2(.U16, $x)", "{{if $x := .X}}-{{.Method2 .U16 $x}}{{end}}-", "-Method2: 16 x-", tVal, true}, + {".Method3(nil constant)", "-{{.Method3 nil}}-", "-Method3: <nil>-", tVal, true}, + {".Method3(nil value)", "-{{.Method3 .MXI.unset}}-", "-Method3: <nil>-", tVal, true}, + {"method on var", "{{if $x := .}}-{{$x.Method2 .U16 $x.X}}{{end}}-", "-Method2: 16 x-", tVal, true}, + {"method on chained var", + "{{range .MSIone}}{{if $.U.TrueFalse $.True}}{{$.U.TrueFalse $.True}}{{else}}WRONG{{end}}{{end}}", + "true", tVal, true}, + {"chained method", + "{{range .MSIone}}{{if $.GetU.TrueFalse $.True}}{{$.U.TrueFalse $.True}}{{else}}WRONG{{end}}{{end}}", + "true", tVal, true}, + {"chained method on variable", + "{{with $x := .}}{{with .SI}}{{$.GetU.TrueFalse $.True}}{{end}}{{end}}", + "true", tVal, true}, + {".NilOKFunc not nil", "{{call .NilOKFunc .PI}}", "false", tVal, true}, + {".NilOKFunc nil", "{{call .NilOKFunc nil}}", "true", tVal, true}, + {"method on nil value from slice", "-{{range .}}{{.Method1 1234}}{{end}}-", "-1234-", tSliceOfNil, true}, + {"method on typed nil interface value", "{{.NonEmptyInterfaceTypedNil.Method0}}", "M0", tVal, true}, + + // Function call builtin. + {".BinaryFunc", "{{call .BinaryFunc `1` `2`}}", "[1=2]", tVal, true}, + {".VariadicFunc0", "{{call .VariadicFunc}}", "<>", tVal, true}, + {".VariadicFunc2", "{{call .VariadicFunc `he` `llo`}}", "<he+llo>", tVal, true}, + {".VariadicFuncInt", "{{call .VariadicFuncInt 33 `he` `llo`}}", "33=<he+llo>", tVal, true}, + {"if .BinaryFunc call", "{{ if .BinaryFunc}}{{call .BinaryFunc `1` `2`}}{{end}}", "[1=2]", tVal, true}, + {"if not .BinaryFunc call", "{{ if not .BinaryFunc}}{{call .BinaryFunc `1` `2`}}{{else}}No{{end}}", "No", tVal, true}, + {"Interface Call", `{{stringer .S}}`, "foozle", map[string]interface{}{"S": bytes.NewBufferString("foozle")}, true}, + {".ErrFunc", "{{call .ErrFunc}}", "bla", tVal, true}, + {"call nil", "{{call nil}}", "", tVal, false}, + + // Erroneous function calls (check args). + {".BinaryFuncTooFew", "{{call .BinaryFunc `1`}}", "", tVal, false}, + {".BinaryFuncTooMany", "{{call .BinaryFunc `1` `2` `3`}}", "", tVal, false}, + {".BinaryFuncBad0", "{{call .BinaryFunc 1 3}}", "", tVal, false}, + {".BinaryFuncBad1", "{{call .BinaryFunc `1` 3}}", "", tVal, false}, + {".VariadicFuncBad0", "{{call .VariadicFunc 3}}", "", tVal, false}, + {".VariadicFuncIntBad0", "{{call .VariadicFuncInt}}", "", tVal, false}, + {".VariadicFuncIntBad`", "{{call .VariadicFuncInt `x`}}", "", tVal, false}, + {".VariadicFuncNilBad", "{{call .VariadicFunc nil}}", "", tVal, false}, + + // Pipelines. + {"pipeline", "-{{.Method0 | .Method2 .U16}}-", "-Method2: 16 M0-", tVal, true}, + {"pipeline func", "-{{call .VariadicFunc `llo` | call .VariadicFunc `he` }}-", "-<he+<llo>>-", tVal, true}, + + // Nil values aren't missing arguments. + {"nil pipeline", "{{ .Empty0 | call .NilOKFunc }}", "true", tVal, true}, + {"nil call arg", "{{ call .NilOKFunc .Empty0 }}", "true", tVal, true}, + {"bad nil pipeline", "{{ .Empty0 | .VariadicFunc }}", "", tVal, false}, + + // Parenthesized expressions + {"parens in pipeline", "{{printf `%d %d %d` (1) (2 | add 3) (add 4 (add 5 6))}}", "1 5 15", tVal, true}, + + // Parenthesized expressions with field accesses + {"parens: $ in paren", "{{($).X}}", "x", tVal, true}, + {"parens: $.GetU in paren", "{{($.GetU).V}}", "v", tVal, true}, + {"parens: $ in paren in pipe", "{{($ | echo).X}}", "x", tVal, true}, + {"parens: spaces and args", `{{(makemap "up" "down" "left" "right").left}}`, "right", tVal, true}, + + // If. + {"if true", "{{if true}}TRUE{{end}}", "TRUE", tVal, true}, + {"if false", "{{if false}}TRUE{{else}}FALSE{{end}}", "FALSE", tVal, true}, + {"if nil", "{{if nil}}TRUE{{end}}", "", tVal, false}, + {"if on typed nil interface value", "{{if .NonEmptyInterfaceTypedNil}}TRUE{{ end }}", "", tVal, true}, + {"if 1", "{{if 1}}NON-ZERO{{else}}ZERO{{end}}", "NON-ZERO", tVal, true}, + {"if 0", "{{if 0}}NON-ZERO{{else}}ZERO{{end}}", "ZERO", tVal, true}, + {"if 1.5", "{{if 1.5}}NON-ZERO{{else}}ZERO{{end}}", "NON-ZERO", tVal, true}, + {"if 0.0", "{{if .FloatZero}}NON-ZERO{{else}}ZERO{{end}}", "ZERO", tVal, true}, + {"if 1.5i", "{{if 1.5i}}NON-ZERO{{else}}ZERO{{end}}", "NON-ZERO", tVal, true}, + {"if 0.0i", "{{if .ComplexZero}}NON-ZERO{{else}}ZERO{{end}}", "ZERO", tVal, true}, + {"if emptystring", "{{if ``}}NON-EMPTY{{else}}EMPTY{{end}}", "EMPTY", tVal, true}, + {"if string", "{{if `notempty`}}NON-EMPTY{{else}}EMPTY{{end}}", "NON-EMPTY", tVal, true}, + {"if emptyslice", "{{if .SIEmpty}}NON-EMPTY{{else}}EMPTY{{end}}", "EMPTY", tVal, true}, + {"if slice", "{{if .SI}}NON-EMPTY{{else}}EMPTY{{end}}", "NON-EMPTY", tVal, true}, + {"if emptymap", "{{if .MSIEmpty}}NON-EMPTY{{else}}EMPTY{{end}}", "EMPTY", tVal, true}, + {"if map", "{{if .MSI}}NON-EMPTY{{else}}EMPTY{{end}}", "NON-EMPTY", tVal, true}, + {"if map unset", "{{if .MXI.none}}NON-ZERO{{else}}ZERO{{end}}", "ZERO", tVal, true}, + {"if map not unset", "{{if not .MXI.none}}ZERO{{else}}NON-ZERO{{end}}", "ZERO", tVal, true}, + {"if $x with $y int", "{{if $x := true}}{{with $y := .I}}{{$x}},{{$y}}{{end}}{{end}}", "true,17", tVal, true}, + {"if $x with $x int", "{{if $x := true}}{{with $x := .I}}{{$x}},{{end}}{{$x}}{{end}}", "17,true", tVal, true}, + {"if else if", "{{if false}}FALSE{{else if true}}TRUE{{end}}", "TRUE", tVal, true}, + {"if else chain", "{{if eq 1 3}}1{{else if eq 2 3}}2{{else if eq 3 3}}3{{end}}", "3", tVal, true}, + + // Print etc. + {"print", `{{print "hello, print"}}`, "hello, print", tVal, true}, + {"print 123", `{{print 1 2 3}}`, "1 2 3", tVal, true}, + {"print nil", `{{print nil}}`, "<nil>", tVal, true}, + {"println", `{{println 1 2 3}}`, "1 2 3\n", tVal, true}, + {"printf int", `{{printf "%04x" 127}}`, "007f", tVal, true}, + {"printf float", `{{printf "%g" 3.5}}`, "3.5", tVal, true}, + {"printf complex", `{{printf "%g" 1+7i}}`, "(1+7i)", tVal, true}, + {"printf string", `{{printf "%s" "hello"}}`, "hello", tVal, true}, + {"printf function", `{{printf "%#q" zeroArgs}}`, "`zeroArgs`", tVal, true}, + {"printf field", `{{printf "%s" .U.V}}`, "v", tVal, true}, + {"printf method", `{{printf "%s" .Method0}}`, "M0", tVal, true}, + {"printf dot", `{{with .I}}{{printf "%d" .}}{{end}}`, "17", tVal, true}, + {"printf var", `{{with $x := .I}}{{printf "%d" $x}}{{end}}`, "17", tVal, true}, + {"printf lots", `{{printf "%d %s %g %s" 127 "hello" 7-3i .Method0}}`, "127 hello (7-3i) M0", tVal, true}, + + // HTML. + {"html", `{{html "<script>alert(\"XSS\");</script>"}}`, + "<script>alert("XSS");</script>", nil, true}, + {"html pipeline", `{{printf "<script>alert(\"XSS\");</script>" | html}}`, + "<script>alert("XSS");</script>", nil, true}, + {"html", `{{html .PS}}`, "a string", tVal, true}, + {"html typed nil", `{{html .NIL}}`, "<nil>", tVal, true}, + {"html untyped nil", `{{html .Empty0}}`, "<nil>", tVal, true}, // NOTE: "<no value>" in text/template + + // JavaScript. + {"js", `{{js .}}`, `It\'d be nice.`, `It'd be nice.`, true}, + + // URL query. + {"urlquery", `{{"http://www.example.org/"|urlquery}}`, "http%3A%2F%2Fwww.example.org%2F", nil, true}, + + // Booleans + {"not", "{{not true}} {{not false}}", "false true", nil, true}, + {"and", "{{and false 0}} {{and 1 0}} {{and 0 true}} {{and 1 1}}", "false 0 0 1", nil, true}, + {"or", "{{or 0 0}} {{or 1 0}} {{or 0 true}} {{or 1 1}}", "0 1 true 1", nil, true}, + {"boolean if", "{{if and true 1 `hi`}}TRUE{{else}}FALSE{{end}}", "TRUE", tVal, true}, + {"boolean if not", "{{if and true 1 `hi` | not}}TRUE{{else}}FALSE{{end}}", "FALSE", nil, true}, + + // Indexing. + {"slice[0]", "{{index .SI 0}}", "3", tVal, true}, + {"slice[1]", "{{index .SI 1}}", "4", tVal, true}, + {"slice[HUGE]", "{{index .SI 10}}", "", tVal, false}, + {"slice[WRONG]", "{{index .SI `hello`}}", "", tVal, false}, + {"slice[nil]", "{{index .SI nil}}", "", tVal, false}, + {"map[one]", "{{index .MSI `one`}}", "1", tVal, true}, + {"map[two]", "{{index .MSI `two`}}", "2", tVal, true}, + {"map[NO]", "{{index .MSI `XXX`}}", "0", tVal, true}, + {"map[nil]", "{{index .MSI nil}}", "", tVal, false}, + {"map[``]", "{{index .MSI ``}}", "0", tVal, true}, + {"map[WRONG]", "{{index .MSI 10}}", "", tVal, false}, + {"double index", "{{index .SMSI 1 `eleven`}}", "11", tVal, true}, + {"nil[1]", "{{index nil 1}}", "", tVal, false}, + {"map MI64S", "{{index .MI64S 2}}", "i642", tVal, true}, + {"map MI32S", "{{index .MI32S 2}}", "two", tVal, true}, + {"map MUI64S", "{{index .MUI64S 3}}", "ui643", tVal, true}, + {"map MI8S", "{{index .MI8S 3}}", "i83", tVal, true}, + {"map MUI8S", "{{index .MUI8S 2}}", "u82", tVal, true}, + {"index of an interface field", "{{index .Empty3 0}}", "7", tVal, true}, + + // Slicing. + {"slice[:]", "{{slice .SI}}", "[3 4 5]", tVal, true}, + {"slice[1:]", "{{slice .SI 1}}", "[4 5]", tVal, true}, + {"slice[1:2]", "{{slice .SI 1 2}}", "[4]", tVal, true}, + {"slice[-1:]", "{{slice .SI -1}}", "", tVal, false}, + {"slice[1:-2]", "{{slice .SI 1 -2}}", "", tVal, false}, + {"slice[1:2:-1]", "{{slice .SI 1 2 -1}}", "", tVal, false}, + {"slice[2:1]", "{{slice .SI 2 1}}", "", tVal, false}, + {"slice[2:2:1]", "{{slice .SI 2 2 1}}", "", tVal, false}, + {"out of range", "{{slice .SI 4 5}}", "", tVal, false}, + {"out of range", "{{slice .SI 2 2 5}}", "", tVal, false}, + {"len(s) < indexes < cap(s)", "{{slice .SICap 6 10}}", "[0 0 0 0]", tVal, true}, + {"len(s) < indexes < cap(s)", "{{slice .SICap 6 10 10}}", "[0 0 0 0]", tVal, true}, + {"indexes > cap(s)", "{{slice .SICap 10 11}}", "", tVal, false}, + {"indexes > cap(s)", "{{slice .SICap 6 10 11}}", "", tVal, false}, + {"array[:]", "{{slice .AI}}", "[3 4 5]", tVal, true}, + {"array[1:]", "{{slice .AI 1}}", "[4 5]", tVal, true}, + {"array[1:2]", "{{slice .AI 1 2}}", "[4]", tVal, true}, + {"string[:]", "{{slice .S}}", "xyz", tVal, true}, + {"string[0:1]", "{{slice .S 0 1}}", "x", tVal, true}, + {"string[1:]", "{{slice .S 1}}", "yz", tVal, true}, + {"string[1:2]", "{{slice .S 1 2}}", "y", tVal, true}, + {"out of range", "{{slice .S 1 5}}", "", tVal, false}, + {"3-index slice of string", "{{slice .S 1 2 2}}", "", tVal, false}, + {"slice of an interface field", "{{slice .Empty3 0 1}}", "[7]", tVal, true}, + + // Len. + {"slice", "{{len .SI}}", "3", tVal, true}, + {"map", "{{len .MSI }}", "3", tVal, true}, + {"len of int", "{{len 3}}", "", tVal, false}, + {"len of nothing", "{{len .Empty0}}", "", tVal, false}, + {"len of an interface field", "{{len .Empty3}}", "2", tVal, true}, + + // With. + {"with true", "{{with true}}{{.}}{{end}}", "true", tVal, true}, + {"with false", "{{with false}}{{.}}{{else}}FALSE{{end}}", "FALSE", tVal, true}, + {"with 1", "{{with 1}}{{.}}{{else}}ZERO{{end}}", "1", tVal, true}, + {"with 0", "{{with 0}}{{.}}{{else}}ZERO{{end}}", "ZERO", tVal, true}, + {"with 1.5", "{{with 1.5}}{{.}}{{else}}ZERO{{end}}", "1.5", tVal, true}, + {"with 0.0", "{{with .FloatZero}}{{.}}{{else}}ZERO{{end}}", "ZERO", tVal, true}, + {"with 1.5i", "{{with 1.5i}}{{.}}{{else}}ZERO{{end}}", "(0+1.5i)", tVal, true}, + {"with 0.0i", "{{with .ComplexZero}}{{.}}{{else}}ZERO{{end}}", "ZERO", tVal, true}, + {"with emptystring", "{{with ``}}{{.}}{{else}}EMPTY{{end}}", "EMPTY", tVal, true}, + {"with string", "{{with `notempty`}}{{.}}{{else}}EMPTY{{end}}", "notempty", tVal, true}, + {"with emptyslice", "{{with .SIEmpty}}{{.}}{{else}}EMPTY{{end}}", "EMPTY", tVal, true}, + {"with slice", "{{with .SI}}{{.}}{{else}}EMPTY{{end}}", "[3 4 5]", tVal, true}, + {"with emptymap", "{{with .MSIEmpty}}{{.}}{{else}}EMPTY{{end}}", "EMPTY", tVal, true}, + {"with map", "{{with .MSIone}}{{.}}{{else}}EMPTY{{end}}", "map[one:1]", tVal, true}, + {"with empty interface, struct field", "{{with .Empty4}}{{.V}}{{end}}", "UinEmpty", tVal, true}, + {"with $x int", "{{with $x := .I}}{{$x}}{{end}}", "17", tVal, true}, + {"with $x struct.U.V", "{{with $x := $}}{{$x.U.V}}{{end}}", "v", tVal, true}, + {"with variable and action", "{{with $x := $}}{{$y := $.U.V}}{{$y}}{{end}}", "v", tVal, true}, + {"with on typed nil interface value", "{{with .NonEmptyInterfaceTypedNil}}TRUE{{ end }}", "", tVal, true}, + + // Range. + {"range []int", "{{range .SI}}-{{.}}-{{end}}", "-3--4--5-", tVal, true}, + {"range empty no else", "{{range .SIEmpty}}-{{.}}-{{end}}", "", tVal, true}, + {"range []int else", "{{range .SI}}-{{.}}-{{else}}EMPTY{{end}}", "-3--4--5-", tVal, true}, + {"range empty else", "{{range .SIEmpty}}-{{.}}-{{else}}EMPTY{{end}}", "EMPTY", tVal, true}, + {"range []bool", "{{range .SB}}-{{.}}-{{end}}", "-true--false-", tVal, true}, + {"range []int method", "{{range .SI | .MAdd .I}}-{{.}}-{{end}}", "-20--21--22-", tVal, true}, + {"range map", "{{range .MSI}}-{{.}}-{{end}}", "-1--3--2-", tVal, true}, + {"range empty map no else", "{{range .MSIEmpty}}-{{.}}-{{end}}", "", tVal, true}, + {"range map else", "{{range .MSI}}-{{.}}-{{else}}EMPTY{{end}}", "-1--3--2-", tVal, true}, + {"range empty map else", "{{range .MSIEmpty}}-{{.}}-{{else}}EMPTY{{end}}", "EMPTY", tVal, true}, + {"range empty interface", "{{range .Empty3}}-{{.}}-{{else}}EMPTY{{end}}", "-7--8-", tVal, true}, + {"range empty nil", "{{range .Empty0}}-{{.}}-{{end}}", "", tVal, true}, + {"range $x SI", "{{range $x := .SI}}<{{$x}}>{{end}}", "<3><4><5>", tVal, true}, + {"range $x $y SI", "{{range $x, $y := .SI}}<{{$x}}={{$y}}>{{end}}", "<0=3><1=4><2=5>", tVal, true}, + {"range $x MSIone", "{{range $x := .MSIone}}<{{$x}}>{{end}}", "<1>", tVal, true}, + {"range $x $y MSIone", "{{range $x, $y := .MSIone}}<{{$x}}={{$y}}>{{end}}", "<one=1>", tVal, true}, + {"range $x PSI", "{{range $x := .PSI}}<{{$x}}>{{end}}", "<21><22><23>", tVal, true}, + {"declare in range", "{{range $x := .PSI}}<{{$foo:=$x}}{{$x}}>{{end}}", "<21><22><23>", tVal, true}, + {"range count", `{{range $i, $x := count 5}}[{{$i}}]{{$x}}{{end}}`, "[0]a[1]b[2]c[3]d[4]e", tVal, true}, + {"range nil count", `{{range $i, $x := count 0}}{{else}}empty{{end}}`, "empty", tVal, true}, + + // Cute examples. + {"or as if true", `{{or .SI "slice is empty"}}`, "[3 4 5]", tVal, true}, + {"or as if false", `{{or .SIEmpty "slice is empty"}}`, "slice is empty", tVal, true}, + + // Error handling. + {"error method, error", "{{.MyError true}}", "", tVal, false}, + {"error method, no error", "{{.MyError false}}", "false", tVal, true}, + + // Numbers + {"decimal", "{{print 1234}}", "1234", tVal, true}, + {"decimal _", "{{print 12_34}}", "1234", tVal, true}, + {"binary", "{{print 0b101}}", "5", tVal, true}, + {"binary _", "{{print 0b_1_0_1}}", "5", tVal, true}, + {"BINARY", "{{print 0B101}}", "5", tVal, true}, + {"octal0", "{{print 0377}}", "255", tVal, true}, + {"octal", "{{print 0o377}}", "255", tVal, true}, + {"octal _", "{{print 0o_3_7_7}}", "255", tVal, true}, + {"OCTAL", "{{print 0O377}}", "255", tVal, true}, + {"hex", "{{print 0x123}}", "291", tVal, true}, + {"hex _", "{{print 0x1_23}}", "291", tVal, true}, + {"HEX", "{{print 0X123ABC}}", "1194684", tVal, true}, + {"float", "{{print 123.4}}", "123.4", tVal, true}, + {"float _", "{{print 0_0_1_2_3.4}}", "123.4", tVal, true}, + {"hex float", "{{print +0x1.ep+2}}", "7.5", tVal, true}, + {"hex float _", "{{print +0x_1.e_0p+0_2}}", "7.5", tVal, true}, + {"HEX float", "{{print +0X1.EP+2}}", "7.5", tVal, true}, + {"print multi", "{{print 1_2_3_4 7.5_00_00_00}}", "1234 7.5", tVal, true}, + {"print multi2", "{{print 1234 0x0_1.e_0p+02}}", "1234 7.5", tVal, true}, + + // Fixed bugs. + // Must separate dot and receiver; otherwise args are evaluated with dot set to variable. + {"bug0", "{{range .MSIone}}{{if $.Method1 .}}X{{end}}{{end}}", "X", tVal, true}, + // Do not loop endlessly in indirect for non-empty interfaces. + // The bug appears with *interface only; looped forever. + {"bug1", "{{.Method0}}", "M0", &iVal, true}, + // Was taking address of interface field, so method set was empty. + {"bug2", "{{$.NonEmptyInterface.Method0}}", "M0", tVal, true}, + // Struct values were not legal in with - mere oversight. + {"bug3", "{{with $}}{{.Method0}}{{end}}", "M0", tVal, true}, + // Nil interface values in if. + {"bug4", "{{if .Empty0}}non-nil{{else}}nil{{end}}", "nil", tVal, true}, + // Stringer. + {"bug5", "{{.Str}}", "foozle", tVal, true}, + {"bug5a", "{{.Err}}", "erroozle", tVal, true}, + // Args need to be indirected and dereferenced sometimes. + {"bug6a", "{{vfunc .V0 .V1}}", "vfunc", tVal, true}, + {"bug6b", "{{vfunc .V0 .V0}}", "vfunc", tVal, true}, + {"bug6c", "{{vfunc .V1 .V0}}", "vfunc", tVal, true}, + {"bug6d", "{{vfunc .V1 .V1}}", "vfunc", tVal, true}, + // Legal parse but illegal execution: non-function should have no arguments. + {"bug7a", "{{3 2}}", "", tVal, false}, + {"bug7b", "{{$x := 1}}{{$x 2}}", "", tVal, false}, + {"bug7c", "{{$x := 1}}{{3 | $x}}", "", tVal, false}, + // Pipelined arg was not being type-checked. + {"bug8a", "{{3|oneArg}}", "", tVal, false}, + {"bug8b", "{{4|dddArg 3}}", "", tVal, false}, + // A bug was introduced that broke map lookups for lower-case names. + {"bug9", "{{.cause}}", "neglect", map[string]string{"cause": "neglect"}, true}, + // Field chain starting with function did not work. + {"bug10", "{{mapOfThree.three}}-{{(mapOfThree).three}}", "3-3", 0, true}, + // Dereferencing nil pointer while evaluating function arguments should not panic. Issue 7333. + {"bug11", "{{valueString .PS}}", "", T{}, false}, + // 0xef gave constant type float64. Issue 8622. + {"bug12xe", "{{printf `%T` 0xef}}", "int", T{}, true}, + {"bug12xE", "{{printf `%T` 0xEE}}", "int", T{}, true}, + {"bug12Xe", "{{printf `%T` 0Xef}}", "int", T{}, true}, + {"bug12XE", "{{printf `%T` 0XEE}}", "int", T{}, true}, + // Chained nodes did not work as arguments. Issue 8473. + {"bug13", "{{print (.Copy).I}}", "17", tVal, true}, + // Didn't protect against nil or literal values in field chains. + {"bug14a", "{{(nil).True}}", "", tVal, false}, + {"bug14b", "{{$x := nil}}{{$x.anything}}", "", tVal, false}, + {"bug14c", `{{$x := (1.0)}}{{$y := ("hello")}}{{$x.anything}}{{$y.true}}`, "", tVal, false}, + // Didn't call validateType on function results. Issue 10800. + {"bug15", "{{valueString returnInt}}", "", tVal, false}, + // Variadic function corner cases. Issue 10946. + {"bug16a", "{{true|printf}}", "", tVal, false}, + {"bug16b", "{{1|printf}}", "", tVal, false}, + {"bug16c", "{{1.1|printf}}", "", tVal, false}, + {"bug16d", "{{'x'|printf}}", "", tVal, false}, + {"bug16e", "{{0i|printf}}", "", tVal, false}, + {"bug16f", "{{true|twoArgs \"xxx\"}}", "", tVal, false}, + {"bug16g", "{{\"aaa\" |twoArgs \"bbb\"}}", "twoArgs=bbbaaa", tVal, true}, + {"bug16h", "{{1|oneArg}}", "", tVal, false}, + {"bug16i", "{{\"aaa\"|oneArg}}", "oneArg=aaa", tVal, true}, + {"bug16j", "{{1+2i|printf \"%v\"}}", "(1+2i)", tVal, true}, + {"bug16k", "{{\"aaa\"|printf }}", "aaa", tVal, true}, + {"bug17a", "{{.NonEmptyInterface.X}}", "x", tVal, true}, + {"bug17b", "-{{.NonEmptyInterface.Method1 1234}}-", "-1234-", tVal, true}, + {"bug17c", "{{len .NonEmptyInterfacePtS}}", "2", tVal, true}, + {"bug17d", "{{index .NonEmptyInterfacePtS 0}}", "a", tVal, true}, + {"bug17e", "{{range .NonEmptyInterfacePtS}}-{{.}}-{{end}}", "-a--b-", tVal, true}, + + // More variadic function corner cases. Some runes would get evaluated + // as constant floats instead of ints. Issue 34483. + {"bug18a", "{{eq . '.'}}", "true", '.', true}, + {"bug18b", "{{eq . 'e'}}", "true", 'e', true}, + {"bug18c", "{{eq . 'P'}}", "true", 'P', true}, +} + +func zeroArgs() string { + return "zeroArgs" +} + +func oneArg(a string) string { + return "oneArg=" + a +} + +func twoArgs(a, b string) string { + return "twoArgs=" + a + b +} + +func dddArg(a int, b ...string) string { + return fmt.Sprintln(a, b) +} + +// count returns a channel that will deliver n sequential 1-letter strings starting at "a" +func count(n int) chan string { + if n == 0 { + return nil + } + c := make(chan string) + go func() { + for i := 0; i < n; i++ { + c <- "abcdefghijklmnop"[i : i+1] + } + close(c) + }() + return c +} + +// vfunc takes a *V and a V +func vfunc(V, *V) string { + return "vfunc" +} + +// valueString takes a string, not a pointer. +func valueString(v string) string { + return "value is ignored" +} + +// returnInt returns an int +func returnInt() int { + return 7 +} + +func add(args ...int) int { + sum := 0 + for _, x := range args { + sum += x + } + return sum +} + +func echo(arg interface{}) interface{} { + return arg +} + +func makemap(arg ...string) map[string]string { + if len(arg)%2 != 0 { + panic("bad makemap") + } + m := make(map[string]string) + for i := 0; i < len(arg); i += 2 { + m[arg[i]] = arg[i+1] + } + return m +} + +func stringer(s fmt.Stringer) string { + return s.String() +} + +func mapOfThree() interface{} { + return map[string]int{"three": 3} +} + +func testExecute(execTests []execTest, template *Template, t *testing.T) { + b := new(bytes.Buffer) + funcs := FuncMap{ + "add": add, + "count": count, + "dddArg": dddArg, + "echo": echo, + "makemap": makemap, + "mapOfThree": mapOfThree, + "oneArg": oneArg, + "returnInt": returnInt, + "stringer": stringer, + "twoArgs": twoArgs, + "typeOf": typeOf, + "valueString": valueString, + "vfunc": vfunc, + "zeroArgs": zeroArgs, + } + for _, test := range execTests { + var tmpl *Template + var err error + if template == nil { + tmpl, err = New(test.name).Funcs(funcs).Parse(test.input) + } else { + tmpl, err = template.Clone() + if err != nil { + t.Errorf("%s: clone error: %s", test.name, err) + continue + } + tmpl, err = tmpl.New(test.name).Funcs(funcs).Parse(test.input) + } + if err != nil { + t.Errorf("%s: parse error: %s", test.name, err) + continue + } + b.Reset() + err = tmpl.Execute(b, test.data) + switch { + case !test.ok && err == nil: + t.Errorf("%s: expected error; got none", test.name) + continue + case test.ok && err != nil: + t.Errorf("%s: unexpected execute error: %s", test.name, err) + continue + case !test.ok && err != nil: + // expected error, got one + if *debug { + fmt.Printf("%s: %s\n\t%s\n", test.name, test.input, err) + } + } + result := b.String() + if result != test.output { + t.Errorf("%s: expected\n\t%q\ngot\n\t%q", test.name, test.output, result) + } + } +} + +func TestExecute(t *testing.T) { + testExecute(execTests, nil, t) +} + +var delimPairs = []string{ + "", "", // default + "{{", "}}", // same as default + "|", "|", // same + "(日)", "(本)", // peculiar +} + +func TestDelims(t *testing.T) { + const hello = "Hello, world" + var value = struct{ Str string }{hello} + for i := 0; i < len(delimPairs); i += 2 { + text := ".Str" + left := delimPairs[i+0] + trueLeft := left + right := delimPairs[i+1] + trueRight := right + if left == "" { // default case + trueLeft = "{{" + } + if right == "" { // default case + trueRight = "}}" + } + text = trueLeft + text + trueRight + // Now add a comment + text += trueLeft + "/*comment*/" + trueRight + // Now add an action containing a string. + text += trueLeft + `"` + trueLeft + `"` + trueRight + // At this point text looks like `{{.Str}}{{/*comment*/}}{{"{{"}}`. + tmpl, err := New("delims").Delims(left, right).Parse(text) + if err != nil { + t.Fatalf("delim %q text %q parse err %s", left, text, err) + } + var b = new(bytes.Buffer) + err = tmpl.Execute(b, value) + if err != nil { + t.Fatalf("delim %q exec err %s", left, err) + } + if b.String() != hello+trueLeft { + t.Errorf("expected %q got %q", hello+trueLeft, b.String()) + } + } +} + +// Check that an error from a method flows back to the top. +func TestExecuteError(t *testing.T) { + b := new(bytes.Buffer) + tmpl := New("error") + _, err := tmpl.Parse("{{.MyError true}}") + if err != nil { + t.Fatalf("parse error: %s", err) + } + err = tmpl.Execute(b, tVal) + if err == nil { + t.Errorf("expected error; got none") + } else if !strings.Contains(err.Error(), myError.Error()) { + if *debug { + fmt.Printf("test execute error: %s\n", err) + } + t.Errorf("expected myError; got %s", err) + } +} + +const execErrorText = `line 1 +line 2 +line 3 +{{template "one" .}} +{{define "one"}}{{template "two" .}}{{end}} +{{define "two"}}{{template "three" .}}{{end}} +{{define "three"}}{{index "hi" $}}{{end}}` + +// Check that an error from a nested template contains all the relevant information. +func TestExecError(t *testing.T) { + tmpl, err := New("top").Parse(execErrorText) + if err != nil { + t.Fatal("parse error:", err) + } + var b bytes.Buffer + err = tmpl.Execute(&b, 5) // 5 is out of range indexing "hi" + if err == nil { + t.Fatal("expected error") + } + const want = `template: top:7:20: executing "three" at <index "hi" $>: error calling index: index out of range: 5` + got := err.Error() + if got != want { + t.Errorf("expected\n%q\ngot\n%q", want, got) + } +} + +func TestJSEscaping(t *testing.T) { + testCases := []struct { + in, exp string + }{ + {`a`, `a`}, + {`'foo`, `\'foo`}, + {`Go "jump" \`, `Go \"jump\" \\`}, + {`Yukihiro says "今日は世界"`, `Yukihiro says \"今日は世界\"`}, + {"unprintable \uFDFF", `unprintable \uFDFF`}, + {`<html>`, `\u003Chtml\u003E`}, + {`no = in attributes`, `no \u003D in attributes`}, + {`' does not become HTML entity`, `\u0026#x27; does not become HTML entity`}, + } + for _, tc := range testCases { + s := JSEscapeString(tc.in) + if s != tc.exp { + t.Errorf("JS escaping [%s] got [%s] want [%s]", tc.in, s, tc.exp) + } + } +} + +// A nice example: walk a binary tree. + +type Tree struct { + Val int + Left, Right *Tree +} + +// Use different delimiters to test Set.Delims. +// Also test the trimming of leading and trailing spaces. +const treeTemplate = ` + (- define "tree" -) + [ + (- .Val -) + (- with .Left -) + (template "tree" . -) + (- end -) + (- with .Right -) + (- template "tree" . -) + (- end -) + ] + (- end -) +` + +func TestTree(t *testing.T) { + var tree = &Tree{ + 1, + &Tree{ + 2, &Tree{ + 3, + &Tree{ + 4, nil, nil, + }, + nil, + }, + &Tree{ + 5, + &Tree{ + 6, nil, nil, + }, + nil, + }, + }, + &Tree{ + 7, + &Tree{ + 8, + &Tree{ + 9, nil, nil, + }, + nil, + }, + &Tree{ + 10, + &Tree{ + 11, nil, nil, + }, + nil, + }, + }, + } + tmpl, err := New("root").Delims("(", ")").Parse(treeTemplate) + if err != nil { + t.Fatal("parse error:", err) + } + var b bytes.Buffer + const expect = "[1[2[3[4]][5[6]]][7[8[9]][10[11]]]]" + // First by looking up the template. + err = tmpl.Lookup("tree").Execute(&b, tree) + if err != nil { + t.Fatal("exec error:", err) + } + result := b.String() + if result != expect { + t.Errorf("expected %q got %q", expect, result) + } + // Then direct to execution. + b.Reset() + err = tmpl.ExecuteTemplate(&b, "tree", tree) + if err != nil { + t.Fatal("exec error:", err) + } + result = b.String() + if result != expect { + t.Errorf("expected %q got %q", expect, result) + } +} + +func TestExecuteOnNewTemplate(t *testing.T) { + // This is issue 3872. + New("Name").Templates() + // This is issue 11379. + // new(Template).Templates() // TODO: crashes + // new(Template).Parse("") // TODO: crashes + // new(Template).New("abc").Parse("") // TODO: crashes + // new(Template).Execute(nil, nil) // TODO: crashes; returns an error (but does not crash) + // new(Template).ExecuteTemplate(nil, "XXX", nil) // TODO: crashes; returns an error (but does not crash) +} + +const testTemplates = `{{define "one"}}one{{end}}{{define "two"}}two{{end}}` + +func TestMessageForExecuteEmpty(t *testing.T) { + // Test a truly empty template. + tmpl := New("empty") + var b bytes.Buffer + err := tmpl.Execute(&b, 0) + if err == nil { + t.Fatal("expected initial error") + } + got := err.Error() + want := `template: "empty" is an incomplete or empty template` // NOTE: text/template has extra "empty: " in message + if got != want { + t.Errorf("expected error %s got %s", want, got) + } + + // Add a non-empty template to check that the error is helpful. + tmpl = New("empty") + tests, err := New("").Parse(testTemplates) + if err != nil { + t.Fatal(err) + } + tmpl.AddParseTree("secondary", tests.Tree) + err = tmpl.Execute(&b, 0) + if err == nil { + t.Fatal("expected second error") + } + got = err.Error() + if got != want { + t.Errorf("expected error %s got %s", want, got) + } + // Make sure we can execute the secondary. + err = tmpl.ExecuteTemplate(&b, "secondary", 0) + if err != nil { + t.Fatal(err) + } +} + +func TestFinalForPrintf(t *testing.T) { + tmpl, err := New("").Parse(`{{"x" | printf}}`) + if err != nil { + t.Fatal(err) + } + var b bytes.Buffer + err = tmpl.Execute(&b, 0) + if err != nil { + t.Fatal(err) + } +} + +type cmpTest struct { + expr string + truth string + ok bool +} + +var cmpTests = []cmpTest{ + {"eq true true", "true", true}, + {"eq true false", "false", true}, + {"eq 1+2i 1+2i", "true", true}, + {"eq 1+2i 1+3i", "false", true}, + {"eq 1.5 1.5", "true", true}, + {"eq 1.5 2.5", "false", true}, + {"eq 1 1", "true", true}, + {"eq 1 2", "false", true}, + {"eq `xy` `xy`", "true", true}, + {"eq `xy` `xyz`", "false", true}, + {"eq .Uthree .Uthree", "true", true}, + {"eq .Uthree .Ufour", "false", true}, + {"eq 3 4 5 6 3", "true", true}, + {"eq 3 4 5 6 7", "false", true}, + {"ne true true", "false", true}, + {"ne true false", "true", true}, + {"ne 1+2i 1+2i", "false", true}, + {"ne 1+2i 1+3i", "true", true}, + {"ne 1.5 1.5", "false", true}, + {"ne 1.5 2.5", "true", true}, + {"ne 1 1", "false", true}, + {"ne 1 2", "true", true}, + {"ne `xy` `xy`", "false", true}, + {"ne `xy` `xyz`", "true", true}, + {"ne .Uthree .Uthree", "false", true}, + {"ne .Uthree .Ufour", "true", true}, + {"lt 1.5 1.5", "false", true}, + {"lt 1.5 2.5", "true", true}, + {"lt 1 1", "false", true}, + {"lt 1 2", "true", true}, + {"lt `xy` `xy`", "false", true}, + {"lt `xy` `xyz`", "true", true}, + {"lt .Uthree .Uthree", "false", true}, + {"lt .Uthree .Ufour", "true", true}, + {"le 1.5 1.5", "true", true}, + {"le 1.5 2.5", "true", true}, + {"le 2.5 1.5", "false", true}, + {"le 1 1", "true", true}, + {"le 1 2", "true", true}, + {"le 2 1", "false", true}, + {"le `xy` `xy`", "true", true}, + {"le `xy` `xyz`", "true", true}, + {"le `xyz` `xy`", "false", true}, + {"le .Uthree .Uthree", "true", true}, + {"le .Uthree .Ufour", "true", true}, + {"le .Ufour .Uthree", "false", true}, + {"gt 1.5 1.5", "false", true}, + {"gt 1.5 2.5", "false", true}, + {"gt 1 1", "false", true}, + {"gt 2 1", "true", true}, + {"gt 1 2", "false", true}, + {"gt `xy` `xy`", "false", true}, + {"gt `xy` `xyz`", "false", true}, + {"gt .Uthree .Uthree", "false", true}, + {"gt .Uthree .Ufour", "false", true}, + {"gt .Ufour .Uthree", "true", true}, + {"ge 1.5 1.5", "true", true}, + {"ge 1.5 2.5", "false", true}, + {"ge 2.5 1.5", "true", true}, + {"ge 1 1", "true", true}, + {"ge 1 2", "false", true}, + {"ge 2 1", "true", true}, + {"ge `xy` `xy`", "true", true}, + {"ge `xy` `xyz`", "false", true}, + {"ge `xyz` `xy`", "true", true}, + {"ge .Uthree .Uthree", "true", true}, + {"ge .Uthree .Ufour", "false", true}, + {"ge .Ufour .Uthree", "true", true}, + // Mixing signed and unsigned integers. + {"eq .Uthree .Three", "true", true}, + {"eq .Three .Uthree", "true", true}, + {"le .Uthree .Three", "true", true}, + {"le .Three .Uthree", "true", true}, + {"ge .Uthree .Three", "true", true}, + {"ge .Three .Uthree", "true", true}, + {"lt .Uthree .Three", "false", true}, + {"lt .Three .Uthree", "false", true}, + {"gt .Uthree .Three", "false", true}, + {"gt .Three .Uthree", "false", true}, + {"eq .Ufour .Three", "false", true}, + {"lt .Ufour .Three", "false", true}, + {"gt .Ufour .Three", "true", true}, + {"eq .NegOne .Uthree", "false", true}, + {"eq .Uthree .NegOne", "false", true}, + {"ne .NegOne .Uthree", "true", true}, + {"ne .Uthree .NegOne", "true", true}, + {"lt .NegOne .Uthree", "true", true}, + {"lt .Uthree .NegOne", "false", true}, + {"le .NegOne .Uthree", "true", true}, + {"le .Uthree .NegOne", "false", true}, + {"gt .NegOne .Uthree", "false", true}, + {"gt .Uthree .NegOne", "true", true}, + {"ge .NegOne .Uthree", "false", true}, + {"ge .Uthree .NegOne", "true", true}, + {"eq (index `x` 0) 'x'", "true", true}, // The example that triggered this rule. + {"eq (index `x` 0) 'y'", "false", true}, + {"eq .V1 .V2", "true", true}, + {"eq .Ptr .Ptr", "true", true}, + {"eq .Ptr .NilPtr", "false", true}, + {"eq .NilPtr .NilPtr", "true", true}, + {"eq .Iface1 .Iface1", "true", true}, + {"eq .Iface1 .Iface2", "false", true}, + {"eq .Iface2 .Iface2", "true", true}, + // Errors + {"eq `xy` 1", "", false}, // Different types. + {"eq 2 2.0", "", false}, // Different types. + {"lt true true", "", false}, // Unordered types. + {"lt 1+0i 1+0i", "", false}, // Unordered types. + {"eq .Ptr 1", "", false}, // Incompatible types. + {"eq .Ptr .NegOne", "", false}, // Incompatible types. + {"eq .Map .Map", "", false}, // Uncomparable types. + {"eq .Map .V1", "", false}, // Uncomparable types. +} + +func TestComparison(t *testing.T) { + b := new(bytes.Buffer) + var cmpStruct = struct { + Uthree, Ufour uint + NegOne, Three int + Ptr, NilPtr *int + Map map[int]int + V1, V2 V + Iface1, Iface2 fmt.Stringer + }{ + Uthree: 3, + Ufour: 4, + NegOne: -1, + Three: 3, + Ptr: new(int), + Iface1: b, + } + for _, test := range cmpTests { + text := fmt.Sprintf("{{if %s}}true{{else}}false{{end}}", test.expr) + tmpl, err := New("empty").Parse(text) + if err != nil { + t.Fatalf("%q: %s", test.expr, err) + } + b.Reset() + err = tmpl.Execute(b, &cmpStruct) + if test.ok && err != nil { + t.Errorf("%s errored incorrectly: %s", test.expr, err) + continue + } + if !test.ok && err == nil { + t.Errorf("%s did not error", test.expr) + continue + } + if b.String() != test.truth { + t.Errorf("%s: want %s; got %s", test.expr, test.truth, b.String()) + } + } +} + +func TestMissingMapKey(t *testing.T) { + data := map[string]int{ + "x": 99, + } + tmpl, err := New("t1").Parse("{{.x}} {{.y}}") + if err != nil { + t.Fatal(err) + } + var b bytes.Buffer + // By default, just get "<no value>" // NOTE: not in html/template, get empty string + err = tmpl.Execute(&b, data) + if err != nil { + t.Fatal(err) + } + want := "99 " + got := b.String() + if got != want { + t.Errorf("got %q; expected %q", got, want) + } + // Same if we set the option explicitly to the default. + tmpl.Option("missingkey=default") + b.Reset() + err = tmpl.Execute(&b, data) + if err != nil { + t.Fatal("default:", err) + } + got = b.String() + if got != want { + t.Errorf("got %q; expected %q", got, want) + } + // Next we ask for a zero value + tmpl.Option("missingkey=zero") + b.Reset() + err = tmpl.Execute(&b, data) + if err != nil { + t.Fatal("zero:", err) + } + want = "99 0" + got = b.String() + if got != want { + t.Errorf("got %q; expected %q", got, want) + } + // Now we ask for an error. + tmpl.Option("missingkey=error") + err = tmpl.Execute(&b, data) + if err == nil { + t.Errorf("expected error; got none") + } + // same Option, but now a nil interface: ask for an error + err = tmpl.Execute(&b, nil) + t.Log(err) + if err == nil { + t.Errorf("expected error for nil-interface; got none") + } +} + +// Test that the error message for multiline unterminated string +// refers to the line number of the opening quote. +func TestUnterminatedStringError(t *testing.T) { + _, err := New("X").Parse("hello\n\n{{`unterminated\n\n\n\n}}\n some more\n\n") + if err == nil { + t.Fatal("expected error") + } + str := err.Error() + if !strings.Contains(str, "X:3: unterminated raw quoted string") { + t.Fatalf("unexpected error: %s", str) + } +} + +const alwaysErrorText = "always be failing" + +var alwaysError = errors.New(alwaysErrorText) + +type ErrorWriter int + +func (e ErrorWriter) Write(p []byte) (int, error) { + return 0, alwaysError +} + +func TestExecuteGivesExecError(t *testing.T) { + // First, a non-execution error shouldn't be an ExecError. + tmpl, err := New("X").Parse("hello") + if err != nil { + t.Fatal(err) + } + err = tmpl.Execute(ErrorWriter(0), 0) + if err == nil { + t.Fatal("expected error; got none") + } + if err.Error() != alwaysErrorText { + t.Errorf("expected %q error; got %q", alwaysErrorText, err) + } + // This one should be an ExecError. + tmpl, err = New("X").Parse("hello, {{.X.Y}}") + if err != nil { + t.Fatal(err) + } + err = tmpl.Execute(io.Discard, 0) + if err == nil { + t.Fatal("expected error; got none") + } + eerr, ok := err.(template.ExecError) + if !ok { + t.Fatalf("did not expect ExecError %s", eerr) + } + expect := "field X in type int" + if !strings.Contains(err.Error(), expect) { + t.Errorf("expected %q; got %q", expect, err) + } +} + +func funcNameTestFunc() int { + return 0 +} + +func TestGoodFuncNames(t *testing.T) { + names := []string{ + "_", + "a", + "a1", + "a1", + "Ӵ", + } + for _, name := range names { + tmpl := New("X").Funcs( + FuncMap{ + name: funcNameTestFunc, + }, + ) + if tmpl == nil { + t.Fatalf("nil result for %q", name) + } + } +} + +func TestBadFuncNames(t *testing.T) { + names := []string{ + "", + "2", + "a-b", + } + for _, name := range names { + testBadFuncName(name, t) + } +} + +func testBadFuncName(name string, t *testing.T) { + t.Helper() + defer func() { + recover() + }() + New("X").Funcs( + FuncMap{ + name: funcNameTestFunc, + }, + ) + // If we get here, the name did not cause a panic, which is how Funcs + // reports an error. + t.Errorf("%q succeeded incorrectly as function name", name) +} + +func TestBlock(t *testing.T) { + const ( + input = `a({{block "inner" .}}bar({{.}})baz{{end}})b` + want = `a(bar(hello)baz)b` + overlay = `{{define "inner"}}foo({{.}})bar{{end}}` + want2 = `a(foo(goodbye)bar)b` + ) + tmpl, err := New("outer").Parse(input) + if err != nil { + t.Fatal(err) + } + tmpl2, err := Must(tmpl.Clone()).Parse(overlay) + if err != nil { + t.Fatal(err) + } + + var buf bytes.Buffer + if err := tmpl.Execute(&buf, "hello"); err != nil { + t.Fatal(err) + } + if got := buf.String(); got != want { + t.Errorf("got %q, want %q", got, want) + } + + buf.Reset() + if err := tmpl2.Execute(&buf, "goodbye"); err != nil { + t.Fatal(err) + } + if got := buf.String(); got != want2 { + t.Errorf("got %q, want %q", got, want2) + } +} + +func TestEvalFieldErrors(t *testing.T) { + tests := []struct { + name, src string + value interface{} + want string + }{ + { + // Check that calling an invalid field on nil pointer + // prints a field error instead of a distracting nil + // pointer error. https://golang.org/issue/15125 + "MissingFieldOnNil", + "{{.MissingField}}", + (*T)(nil), + "can't evaluate field MissingField in type *template.T", + }, + { + "MissingFieldOnNonNil", + "{{.MissingField}}", + &T{}, + "can't evaluate field MissingField in type *template.T", + }, + { + "ExistingFieldOnNil", + "{{.X}}", + (*T)(nil), + "nil pointer evaluating *template.T.X", + }, + { + "MissingKeyOnNilMap", + "{{.MissingKey}}", + (*map[string]string)(nil), + "nil pointer evaluating *map[string]string.MissingKey", + }, + { + "MissingKeyOnNilMapPtr", + "{{.MissingKey}}", + (*map[string]string)(nil), + "nil pointer evaluating *map[string]string.MissingKey", + }, + { + "MissingKeyOnMapPtrToNil", + "{{.MissingKey}}", + &map[string]string{}, + "<nil>", + }, + } + for _, tc := range tests { + t.Run(tc.name, func(t *testing.T) { + tmpl := Must(New("tmpl").Parse(tc.src)) + err := tmpl.Execute(io.Discard, tc.value) + got := "<nil>" + if err != nil { + got = err.Error() + } + if !strings.HasSuffix(got, tc.want) { + t.Fatalf("got error %q, want %q", got, tc.want) + } + }) + } +} + +func TestMaxExecDepth(t *testing.T) { + if testing.Short() { + t.Skip("skipping in -short mode") + } + tmpl := Must(New("tmpl").Parse(`{{template "tmpl" .}}`)) + err := tmpl.Execute(io.Discard, nil) + got := "<nil>" + if err != nil { + got = err.Error() + } + const want = "exceeded maximum template depth" + if !strings.Contains(got, want) { + t.Errorf("got error %q; want %q", got, want) + } +} + +func TestAddrOfIndex(t *testing.T) { + // golang.org/issue/14916. + // Before index worked on reflect.Values, the .String could not be + // found on the (incorrectly unaddressable) V value, + // in contrast to range, which worked fine. + // Also testing that passing a reflect.Value to tmpl.Execute works. + texts := []string{ + `{{range .}}{{.String}}{{end}}`, + `{{with index . 0}}{{.String}}{{end}}`, + } + for _, text := range texts { + tmpl := Must(New("tmpl").Parse(text)) + var buf bytes.Buffer + err := tmpl.Execute(&buf, reflect.ValueOf([]V{{1}})) + if err != nil { + t.Fatalf("%s: Execute: %v", text, err) + } + if buf.String() != "<1>" { + t.Fatalf("%s: template output = %q, want %q", text, &buf, "<1>") + } + } +} + +func TestInterfaceValues(t *testing.T) { + // golang.org/issue/17714. + // Before index worked on reflect.Values, interface values + // were always implicitly promoted to the underlying value, + // except that nil interfaces were promoted to the zero reflect.Value. + // Eliminating a round trip to interface{} and back to reflect.Value + // eliminated this promotion, breaking these cases. + tests := []struct { + text string + out string + }{ + {`{{index .Nil 1}}`, "ERROR: index of untyped nil"}, + {`{{index .Slice 2}}`, "2"}, + {`{{index .Slice .Two}}`, "2"}, + {`{{call .Nil 1}}`, "ERROR: call of nil"}, + {`{{call .PlusOne 1}}`, "2"}, + {`{{call .PlusOne .One}}`, "2"}, + {`{{and (index .Slice 0) true}}`, "0"}, + {`{{and .Zero true}}`, "0"}, + {`{{and (index .Slice 1) false}}`, "false"}, + {`{{and .One false}}`, "false"}, + {`{{or (index .Slice 0) false}}`, "false"}, + {`{{or .Zero false}}`, "false"}, + {`{{or (index .Slice 1) true}}`, "1"}, + {`{{or .One true}}`, "1"}, + {`{{not (index .Slice 0)}}`, "true"}, + {`{{not .Zero}}`, "true"}, + {`{{not (index .Slice 1)}}`, "false"}, + {`{{not .One}}`, "false"}, + {`{{eq (index .Slice 0) .Zero}}`, "true"}, + {`{{eq (index .Slice 1) .One}}`, "true"}, + {`{{ne (index .Slice 0) .Zero}}`, "false"}, + {`{{ne (index .Slice 1) .One}}`, "false"}, + {`{{ge (index .Slice 0) .One}}`, "false"}, + {`{{ge (index .Slice 1) .Zero}}`, "true"}, + {`{{gt (index .Slice 0) .One}}`, "false"}, + {`{{gt (index .Slice 1) .Zero}}`, "true"}, + {`{{le (index .Slice 0) .One}}`, "true"}, + {`{{le (index .Slice 1) .Zero}}`, "false"}, + {`{{lt (index .Slice 0) .One}}`, "true"}, + {`{{lt (index .Slice 1) .Zero}}`, "false"}, + } + + for _, tt := range tests { + tmpl := Must(New("tmpl").Parse(tt.text)) + var buf bytes.Buffer + err := tmpl.Execute(&buf, map[string]interface{}{ + "PlusOne": func(n int) int { + return n + 1 + }, + "Slice": []int{0, 1, 2, 3}, + "One": 1, + "Two": 2, + "Nil": nil, + "Zero": 0, + }) + if strings.HasPrefix(tt.out, "ERROR:") { + e := strings.TrimSpace(strings.TrimPrefix(tt.out, "ERROR:")) + if err == nil || !strings.Contains(err.Error(), e) { + t.Errorf("%s: Execute: %v, want error %q", tt.text, err, e) + } + continue + } + if err != nil { + t.Errorf("%s: Execute: %v", tt.text, err) + continue + } + if buf.String() != tt.out { + t.Errorf("%s: template output = %q, want %q", tt.text, &buf, tt.out) + } + } +} + +// Check that panics during calls are recovered and returned as errors. +func TestExecutePanicDuringCall(t *testing.T) { + funcs := map[string]interface{}{ + "doPanic": func() string { + panic("custom panic string") + }, + } + tests := []struct { + name string + input string + data interface{} + wantErr string + }{ + { + "direct func call panics", + "{{doPanic}}", (*T)(nil), + `template: t:1:2: executing "t" at <doPanic>: error calling doPanic: custom panic string`, + }, + { + "indirect func call panics", + "{{call doPanic}}", (*T)(nil), + `template: t:1:7: executing "t" at <doPanic>: error calling doPanic: custom panic string`, + }, + { + "direct method call panics", + "{{.GetU}}", (*T)(nil), + `template: t:1:2: executing "t" at <.GetU>: error calling GetU: runtime error: invalid memory address or nil pointer dereference`, + }, + { + "indirect method call panics", + "{{call .GetU}}", (*T)(nil), + `template: t:1:7: executing "t" at <.GetU>: error calling GetU: runtime error: invalid memory address or nil pointer dereference`, + }, + { + "func field call panics", + "{{call .PanicFunc}}", tVal, + `template: t:1:2: executing "t" at <call .PanicFunc>: error calling call: test panic`, + }, + { + "method call on nil interface", + "{{.NonEmptyInterfaceNil.Method0}}", tVal, + `template: t:1:23: executing "t" at <.NonEmptyInterfaceNil.Method0>: nil pointer evaluating template.I.Method0`, + }, + } + for _, tc := range tests { + b := new(bytes.Buffer) + tmpl, err := New("t").Funcs(funcs).Parse(tc.input) + if err != nil { + t.Fatalf("parse error: %s", err) + } + err = tmpl.Execute(b, tc.data) + if err == nil { + t.Errorf("%s: expected error; got none", tc.name) + } else if !strings.Contains(err.Error(), tc.wantErr) { + if *debug { + fmt.Printf("%s: test execute error: %s\n", tc.name, err) + } + t.Errorf("%s: expected error:\n%s\ngot:\n%s", tc.name, tc.wantErr, err) + } + } +} + +// Issue 31810. Check that a parenthesized first argument behaves properly. +func TestIssue31810(t *testing.T) { + t.Skip("broken in html/template") + + // A simple value with no arguments is fine. + var b bytes.Buffer + const text = "{{ (.) }}" + tmpl, err := New("").Parse(text) + if err != nil { + t.Error(err) + } + err = tmpl.Execute(&b, "result") + if err != nil { + t.Error(err) + } + if b.String() != "result" { + t.Errorf("%s got %q, expected %q", text, b.String(), "result") + } + + // Even a plain function fails - need to use call. + f := func() string { return "result" } + b.Reset() + err = tmpl.Execute(&b, f) + if err == nil { + t.Error("expected error with no call, got none") + } + + // Works if the function is explicitly called. + const textCall = "{{ (call .) }}" + tmpl, err = New("").Parse(textCall) + b.Reset() + err = tmpl.Execute(&b, f) + if err != nil { + t.Error(err) + } + if b.String() != "result" { + t.Errorf("%s got %q, expected %q", textCall, b.String(), "result") + } +} + +// Issue 39807. There was a race applying escapeTemplate. + +const raceText = ` +{{- define "jstempl" -}} +var v = "v"; +{{- end -}} +<script type="application/javascript"> +{{ template "jstempl" $ }} +</script> +` + +func TestEscapeRace(t *testing.T) { + tmpl := New("") + _, err := tmpl.New("templ.html").Parse(raceText) + if err != nil { + t.Fatal(err) + } + const count = 20 + for i := 0; i < count; i++ { + _, err := tmpl.New(fmt.Sprintf("x%d.html", i)).Parse(`{{ template "templ.html" .}}`) + if err != nil { + t.Fatal(err) + } + } + + var wg sync.WaitGroup + for i := 0; i < 10; i++ { + wg.Add(1) + go func() { + defer wg.Done() + for j := 0; j < count; j++ { + sub := tmpl.Lookup(fmt.Sprintf("x%d.html", j)) + if err := sub.Execute(io.Discard, nil); err != nil { + t.Error(err) + } + } + }() + } + wg.Wait() +} + +func TestRecursiveExecute(t *testing.T) { + tmpl := New("") + + recur := func() (HTML, error) { + var sb strings.Builder + if err := tmpl.ExecuteTemplate(&sb, "subroutine", nil); err != nil { + t.Fatal(err) + } + return HTML(sb.String()), nil + } + + m := FuncMap{ + "recur": recur, + } + + top, err := tmpl.New("x.html").Funcs(m).Parse(`{{recur}}`) + if err != nil { + t.Fatal(err) + } + _, err = tmpl.New("subroutine").Parse(`<a href="/x?p={{"'a<b'"}}">`) + if err != nil { + t.Fatal(err) + } + if err := top.Execute(io.Discard, nil); err != nil { + t.Fatal(err) + } +} + +// recursiveInvoker is for TestRecursiveExecuteViaMethod. +type recursiveInvoker struct { + t *testing.T + tmpl *Template +} + +func (r *recursiveInvoker) Recur() (string, error) { + var sb strings.Builder + if err := r.tmpl.ExecuteTemplate(&sb, "subroutine", nil); err != nil { + r.t.Fatal(err) + } + return sb.String(), nil +} + +func TestRecursiveExecuteViaMethod(t *testing.T) { + tmpl := New("") + top, err := tmpl.New("x.html").Parse(`{{.Recur}}`) + if err != nil { + t.Fatal(err) + } + _, err = tmpl.New("subroutine").Parse(`<a href="/x?p={{"'a<b'"}}">`) + if err != nil { + t.Fatal(err) + } + r := &recursiveInvoker{ + t: t, + tmpl: tmpl, + } + if err := top.Execute(io.Discard, r); err != nil { + t.Fatal(err) + } +} + +// Issue 43295. +func TestTemplateFuncsAfterClone(t *testing.T) { + s := `{{ f . }}` + want := "test" + orig := New("orig").Funcs(map[string]interface{}{ + "f": func(in string) string { + return in + }, + }).New("child") + + overviewTmpl := Must(Must(orig.Clone()).Parse(s)) + var out strings.Builder + if err := overviewTmpl.Execute(&out, want); err != nil { + t.Fatal(err) + } + if got := out.String(); got != want { + t.Fatalf("got %q; want %q", got, want) + } +} diff --git a/src/html/template/html.go b/src/html/template/html.go new file mode 100644 index 0000000..356b829 --- /dev/null +++ b/src/html/template/html.go @@ -0,0 +1,265 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package template + +import ( + "bytes" + "fmt" + "strings" + "unicode/utf8" +) + +// htmlNospaceEscaper escapes for inclusion in unquoted attribute values. +func htmlNospaceEscaper(args ...interface{}) string { + s, t := stringify(args...) + if t == contentTypeHTML { + return htmlReplacer(stripTags(s), htmlNospaceNormReplacementTable, false) + } + return htmlReplacer(s, htmlNospaceReplacementTable, false) +} + +// attrEscaper escapes for inclusion in quoted attribute values. +func attrEscaper(args ...interface{}) string { + s, t := stringify(args...) + if t == contentTypeHTML { + return htmlReplacer(stripTags(s), htmlNormReplacementTable, true) + } + return htmlReplacer(s, htmlReplacementTable, true) +} + +// rcdataEscaper escapes for inclusion in an RCDATA element body. +func rcdataEscaper(args ...interface{}) string { + s, t := stringify(args...) + if t == contentTypeHTML { + return htmlReplacer(s, htmlNormReplacementTable, true) + } + return htmlReplacer(s, htmlReplacementTable, true) +} + +// htmlEscaper escapes for inclusion in HTML text. +func htmlEscaper(args ...interface{}) string { + s, t := stringify(args...) + if t == contentTypeHTML { + return s + } + return htmlReplacer(s, htmlReplacementTable, true) +} + +// htmlReplacementTable contains the runes that need to be escaped +// inside a quoted attribute value or in a text node. +var htmlReplacementTable = []string{ + // https://www.w3.org/TR/html5/syntax.html#attribute-value-(unquoted)-state + // U+0000 NULL Parse error. Append a U+FFFD REPLACEMENT + // CHARACTER character to the current attribute's value. + // " + // and similarly + // https://www.w3.org/TR/html5/syntax.html#before-attribute-value-state + 0: "\uFFFD", + '"': """, + '&': "&", + '\'': "'", + '+': "+", + '<': "<", + '>': ">", +} + +// htmlNormReplacementTable is like htmlReplacementTable but without '&' to +// avoid over-encoding existing entities. +var htmlNormReplacementTable = []string{ + 0: "\uFFFD", + '"': """, + '\'': "'", + '+': "+", + '<': "<", + '>': ">", +} + +// htmlNospaceReplacementTable contains the runes that need to be escaped +// inside an unquoted attribute value. +// The set of runes escaped is the union of the HTML specials and +// those determined by running the JS below in browsers: +// <div id=d></div> +// <script>(function () { +// var a = [], d = document.getElementById("d"), i, c, s; +// for (i = 0; i < 0x10000; ++i) { +// c = String.fromCharCode(i); +// d.innerHTML = "<span title=" + c + "lt" + c + "></span>" +// s = d.getElementsByTagName("SPAN")[0]; +// if (!s || s.title !== c + "lt" + c) { a.push(i.toString(16)); } +// } +// document.write(a.join(", ")); +// })()</script> +var htmlNospaceReplacementTable = []string{ + 0: "�", + '\t': "	", + '\n': " ", + '\v': "", + '\f': "", + '\r': " ", + ' ': " ", + '"': """, + '&': "&", + '\'': "'", + '+': "+", + '<': "<", + '=': "=", + '>': ">", + // A parse error in the attribute value (unquoted) and + // before attribute value states. + // Treated as a quoting character by IE. + '`': "`", +} + +// htmlNospaceNormReplacementTable is like htmlNospaceReplacementTable but +// without '&' to avoid over-encoding existing entities. +var htmlNospaceNormReplacementTable = []string{ + 0: "�", + '\t': "	", + '\n': " ", + '\v': "", + '\f': "", + '\r': " ", + ' ': " ", + '"': """, + '\'': "'", + '+': "+", + '<': "<", + '=': "=", + '>': ">", + // A parse error in the attribute value (unquoted) and + // before attribute value states. + // Treated as a quoting character by IE. + '`': "`", +} + +// htmlReplacer returns s with runes replaced according to replacementTable +// and when badRunes is true, certain bad runes are allowed through unescaped. +func htmlReplacer(s string, replacementTable []string, badRunes bool) string { + written, b := 0, new(strings.Builder) + r, w := rune(0), 0 + for i := 0; i < len(s); i += w { + // Cannot use 'for range s' because we need to preserve the width + // of the runes in the input. If we see a decoding error, the input + // width will not be utf8.Runelen(r) and we will overrun the buffer. + r, w = utf8.DecodeRuneInString(s[i:]) + if int(r) < len(replacementTable) { + if repl := replacementTable[r]; len(repl) != 0 { + if written == 0 { + b.Grow(len(s)) + } + b.WriteString(s[written:i]) + b.WriteString(repl) + written = i + w + } + } else if badRunes { + // No-op. + // IE does not allow these ranges in unquoted attrs. + } else if 0xfdd0 <= r && r <= 0xfdef || 0xfff0 <= r && r <= 0xffff { + if written == 0 { + b.Grow(len(s)) + } + fmt.Fprintf(b, "%s&#x%x;", s[written:i], r) + written = i + w + } + } + if written == 0 { + return s + } + b.WriteString(s[written:]) + return b.String() +} + +// stripTags takes a snippet of HTML and returns only the text content. +// For example, `<b>¡Hi!</b> <script>...</script>` -> `¡Hi! `. +func stripTags(html string) string { + var b bytes.Buffer + s, c, i, allText := []byte(html), context{}, 0, true + // Using the transition funcs helps us avoid mangling + // `<div title="1>2">` or `I <3 Ponies!`. + for i != len(s) { + if c.delim == delimNone { + st := c.state + // Use RCDATA instead of parsing into JS or CSS styles. + if c.element != elementNone && !isInTag(st) { + st = stateRCDATA + } + d, nread := transitionFunc[st](c, s[i:]) + i1 := i + nread + if c.state == stateText || c.state == stateRCDATA { + // Emit text up to the start of the tag or comment. + j := i1 + if d.state != c.state { + for j1 := j - 1; j1 >= i; j1-- { + if s[j1] == '<' { + j = j1 + break + } + } + } + b.Write(s[i:j]) + } else { + allText = false + } + c, i = d, i1 + continue + } + i1 := i + bytes.IndexAny(s[i:], delimEnds[c.delim]) + if i1 < i { + break + } + if c.delim != delimSpaceOrTagEnd { + // Consume any quote. + i1++ + } + c, i = context{state: stateTag, element: c.element}, i1 + } + if allText { + return html + } else if c.state == stateText || c.state == stateRCDATA { + b.Write(s[i:]) + } + return b.String() +} + +// htmlNameFilter accepts valid parts of an HTML attribute or tag name or +// a known-safe HTML attribute. +func htmlNameFilter(args ...interface{}) string { + s, t := stringify(args...) + if t == contentTypeHTMLAttr { + return s + } + if len(s) == 0 { + // Avoid violation of structure preservation. + // <input checked {{.K}}={{.V}}>. + // Without this, if .K is empty then .V is the value of + // checked, but otherwise .V is the value of the attribute + // named .K. + return filterFailsafe + } + s = strings.ToLower(s) + if t := attrType(s); t != contentTypePlain { + // TODO: Split attr and element name part filters so we can recognize known attributes. + return filterFailsafe + } + for _, r := range s { + switch { + case '0' <= r && r <= '9': + case 'a' <= r && r <= 'z': + default: + return filterFailsafe + } + } + return s +} + +// commentEscaper returns the empty string regardless of input. +// Comment content does not correspond to any parsed structure or +// human-readable content, so the simplest and most secure policy is to drop +// content interpolated into comments. +// This approach is equally valid whether or not static comment content is +// removed from the template. +func commentEscaper(args ...interface{}) string { + return "" +} diff --git a/src/html/template/html_test.go b/src/html/template/html_test.go new file mode 100644 index 0000000..f04ee04 --- /dev/null +++ b/src/html/template/html_test.go @@ -0,0 +1,97 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package template + +import ( + "html" + "strings" + "testing" +) + +func TestHTMLNospaceEscaper(t *testing.T) { + input := ("\x00\x01\x02\x03\x04\x05\x06\x07\x08\t\n\x0b\x0c\r\x0e\x0f" + + "\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f" + + ` !"#$%&'()*+,-./` + + `0123456789:;<=>?` + + `@ABCDEFGHIJKLMNO` + + `PQRSTUVWXYZ[\]^_` + + "`abcdefghijklmno" + + "pqrstuvwxyz{|}~\x7f" + + "\u00A0\u0100\u2028\u2029\ufeff\ufdec\U0001D11E" + + "erroneous\x960") // keep at the end + + want := ("�\x01\x02\x03\x04\x05\x06\x07" + + "\x08	  \x0E\x0F" + + "\x10\x11\x12\x13\x14\x15\x16\x17" + + "\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f" + + ` !"#$%&'()*+,-./` + + `0123456789:;<=>?` + + `@ABCDEFGHIJKLMNO` + + `PQRSTUVWXYZ[\]^_` + + ``abcdefghijklmno` + + `pqrstuvwxyz{|}~` + "\u007f" + + "\u00A0\u0100\u2028\u2029\ufeff\U0001D11E" + + "erroneous�0") // keep at the end + + got := htmlNospaceEscaper(input) + if got != want { + t.Errorf("encode: want\n\t%q\nbut got\n\t%q", want, got) + } + + r := strings.NewReplacer("\x00", "\ufffd", "\x96", "\ufffd") + got, want = html.UnescapeString(got), r.Replace(input) + if want != got { + t.Errorf("decode: want\n\t%q\nbut got\n\t%q", want, got) + } +} + +func TestStripTags(t *testing.T) { + tests := []struct { + input, want string + }{ + {"", ""}, + {"Hello, World!", "Hello, World!"}, + {"foo&bar", "foo&bar"}, + {`Hello <a href="www.example.com/">World</a>!`, "Hello World!"}, + {"Foo <textarea>Bar</textarea> Baz", "Foo Bar Baz"}, + {"Foo <!-- Bar --> Baz", "Foo Baz"}, + {"<", "<"}, + {"foo < bar", "foo < bar"}, + {`Foo<script type="text/javascript">alert(1337)</script>Bar`, "FooBar"}, + {`Foo<div title="1>2">Bar`, "FooBar"}, + {`I <3 Ponies!`, `I <3 Ponies!`}, + {`<script>foo()</script>`, ``}, + } + + for _, test := range tests { + if got := stripTags(test.input); got != test.want { + t.Errorf("%q: want %q, got %q", test.input, test.want, got) + } + } +} + +func BenchmarkHTMLNospaceEscaper(b *testing.B) { + for i := 0; i < b.N; i++ { + htmlNospaceEscaper("The <i>quick</i>,\r\n<span style='color:brown'>brown</span> fox jumps\u2028over the <canine class=\"lazy\">dog</canine>") + } +} + +func BenchmarkHTMLNospaceEscaperNoSpecials(b *testing.B) { + for i := 0; i < b.N; i++ { + htmlNospaceEscaper("The_quick,_brown_fox_jumps_over_the_lazy_dog.") + } +} + +func BenchmarkStripTags(b *testing.B) { + for i := 0; i < b.N; i++ { + stripTags("The <i>quick</i>,\r\n<span style='color:brown'>brown</span> fox jumps\u2028over the <canine class=\"lazy\">dog</canine>") + } +} + +func BenchmarkStripTagsNoSpecials(b *testing.B) { + for i := 0; i < b.N; i++ { + stripTags("The quick, brown fox jumps over the lazy dog.") + } +} diff --git a/src/html/template/js.go b/src/html/template/js.go new file mode 100644 index 0000000..ea9c183 --- /dev/null +++ b/src/html/template/js.go @@ -0,0 +1,431 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package template + +import ( + "bytes" + "encoding/json" + "fmt" + "reflect" + "strings" + "unicode/utf8" +) + +// nextJSCtx returns the context that determines whether a slash after the +// given run of tokens starts a regular expression instead of a division +// operator: / or /=. +// +// This assumes that the token run does not include any string tokens, comment +// tokens, regular expression literal tokens, or division operators. +// +// This fails on some valid but nonsensical JavaScript programs like +// "x = ++/foo/i" which is quite different than "x++/foo/i", but is not known to +// fail on any known useful programs. It is based on the draft +// JavaScript 2.0 lexical grammar and requires one token of lookbehind: +// https://www.mozilla.org/js/language/js20-2000-07/rationale/syntax.html +func nextJSCtx(s []byte, preceding jsCtx) jsCtx { + s = bytes.TrimRight(s, "\t\n\f\r \u2028\u2029") + if len(s) == 0 { + return preceding + } + + // All cases below are in the single-byte UTF-8 group. + switch c, n := s[len(s)-1], len(s); c { + case '+', '-': + // ++ and -- are not regexp preceders, but + and - are whether + // they are used as infix or prefix operators. + start := n - 1 + // Count the number of adjacent dashes or pluses. + for start > 0 && s[start-1] == c { + start-- + } + if (n-start)&1 == 1 { + // Reached for trailing minus signs since "---" is the + // same as "-- -". + return jsCtxRegexp + } + return jsCtxDivOp + case '.': + // Handle "42." + if n != 1 && '0' <= s[n-2] && s[n-2] <= '9' { + return jsCtxDivOp + } + return jsCtxRegexp + // Suffixes for all punctuators from section 7.7 of the language spec + // that only end binary operators not handled above. + case ',', '<', '>', '=', '*', '%', '&', '|', '^', '?': + return jsCtxRegexp + // Suffixes for all punctuators from section 7.7 of the language spec + // that are prefix operators not handled above. + case '!', '~': + return jsCtxRegexp + // Matches all the punctuators from section 7.7 of the language spec + // that are open brackets not handled above. + case '(', '[': + return jsCtxRegexp + // Matches all the punctuators from section 7.7 of the language spec + // that precede expression starts. + case ':', ';', '{': + return jsCtxRegexp + // CAVEAT: the close punctuators ('}', ']', ')') precede div ops and + // are handled in the default except for '}' which can precede a + // division op as in + // ({ valueOf: function () { return 42 } } / 2 + // which is valid, but, in practice, developers don't divide object + // literals, so our heuristic works well for code like + // function () { ... } /foo/.test(x) && sideEffect(); + // The ')' punctuator can precede a regular expression as in + // if (b) /foo/.test(x) && ... + // but this is much less likely than + // (a + b) / c + case '}': + return jsCtxRegexp + default: + // Look for an IdentifierName and see if it is a keyword that + // can precede a regular expression. + j := n + for j > 0 && isJSIdentPart(rune(s[j-1])) { + j-- + } + if regexpPrecederKeywords[string(s[j:])] { + return jsCtxRegexp + } + } + // Otherwise is a punctuator not listed above, or + // a string which precedes a div op, or an identifier + // which precedes a div op. + return jsCtxDivOp +} + +// regexpPrecederKeywords is a set of reserved JS keywords that can precede a +// regular expression in JS source. +var regexpPrecederKeywords = map[string]bool{ + "break": true, + "case": true, + "continue": true, + "delete": true, + "do": true, + "else": true, + "finally": true, + "in": true, + "instanceof": true, + "return": true, + "throw": true, + "try": true, + "typeof": true, + "void": true, +} + +var jsonMarshalType = reflect.TypeOf((*json.Marshaler)(nil)).Elem() + +// indirectToJSONMarshaler returns the value, after dereferencing as many times +// as necessary to reach the base type (or nil) or an implementation of json.Marshal. +func indirectToJSONMarshaler(a interface{}) interface{} { + // text/template now supports passing untyped nil as a func call + // argument, so we must support it. Otherwise we'd panic below, as one + // cannot call the Type or Interface methods on an invalid + // reflect.Value. See golang.org/issue/18716. + if a == nil { + return nil + } + + v := reflect.ValueOf(a) + for !v.Type().Implements(jsonMarshalType) && v.Kind() == reflect.Ptr && !v.IsNil() { + v = v.Elem() + } + return v.Interface() +} + +// jsValEscaper escapes its inputs to a JS Expression (section 11.14) that has +// neither side-effects nor free variables outside (NaN, Infinity). +func jsValEscaper(args ...interface{}) string { + var a interface{} + if len(args) == 1 { + a = indirectToJSONMarshaler(args[0]) + switch t := a.(type) { + case JS: + return string(t) + case JSStr: + // TODO: normalize quotes. + return `"` + string(t) + `"` + case json.Marshaler: + // Do not treat as a Stringer. + case fmt.Stringer: + a = t.String() + } + } else { + for i, arg := range args { + args[i] = indirectToJSONMarshaler(arg) + } + a = fmt.Sprint(args...) + } + // TODO: detect cycles before calling Marshal which loops infinitely on + // cyclic data. This may be an unacceptable DoS risk. + b, err := json.Marshal(a) + if err != nil { + // Put a space before comment so that if it is flush against + // a division operator it is not turned into a line comment: + // x/{{y}} + // turning into + // x//* error marshaling y: + // second line of error message */null + return fmt.Sprintf(" /* %s */null ", strings.ReplaceAll(err.Error(), "*/", "* /")) + } + + // TODO: maybe post-process output to prevent it from containing + // "<!--", "-->", "<![CDATA[", "]]>", or "</script" + // in case custom marshalers produce output containing those. + // Note: Do not use \x escaping to save bytes because it is not JSON compatible and this escaper + // supports ld+json content-type. + if len(b) == 0 { + // In, `x=y/{{.}}*z` a json.Marshaler that produces "" should + // not cause the output `x=y/*z`. + return " null " + } + first, _ := utf8.DecodeRune(b) + last, _ := utf8.DecodeLastRune(b) + var buf strings.Builder + // Prevent IdentifierNames and NumericLiterals from running into + // keywords: in, instanceof, typeof, void + pad := isJSIdentPart(first) || isJSIdentPart(last) + if pad { + buf.WriteByte(' ') + } + written := 0 + // Make sure that json.Marshal escapes codepoints U+2028 & U+2029 + // so it falls within the subset of JSON which is valid JS. + for i := 0; i < len(b); { + rune, n := utf8.DecodeRune(b[i:]) + repl := "" + if rune == 0x2028 { + repl = `\u2028` + } else if rune == 0x2029 { + repl = `\u2029` + } + if repl != "" { + buf.Write(b[written:i]) + buf.WriteString(repl) + written = i + n + } + i += n + } + if buf.Len() != 0 { + buf.Write(b[written:]) + if pad { + buf.WriteByte(' ') + } + return buf.String() + } + return string(b) +} + +// jsStrEscaper produces a string that can be included between quotes in +// JavaScript source, in JavaScript embedded in an HTML5 <script> element, +// or in an HTML5 event handler attribute such as onclick. +func jsStrEscaper(args ...interface{}) string { + s, t := stringify(args...) + if t == contentTypeJSStr { + return replace(s, jsStrNormReplacementTable) + } + return replace(s, jsStrReplacementTable) +} + +// jsRegexpEscaper behaves like jsStrEscaper but escapes regular expression +// specials so the result is treated literally when included in a regular +// expression literal. /foo{{.X}}bar/ matches the string "foo" followed by +// the literal text of {{.X}} followed by the string "bar". +func jsRegexpEscaper(args ...interface{}) string { + s, _ := stringify(args...) + s = replace(s, jsRegexpReplacementTable) + if s == "" { + // /{{.X}}/ should not produce a line comment when .X == "". + return "(?:)" + } + return s +} + +// replace replaces each rune r of s with replacementTable[r], provided that +// r < len(replacementTable). If replacementTable[r] is the empty string then +// no replacement is made. +// It also replaces runes U+2028 and U+2029 with the raw strings `\u2028` and +// `\u2029`. +func replace(s string, replacementTable []string) string { + var b strings.Builder + r, w, written := rune(0), 0, 0 + for i := 0; i < len(s); i += w { + // See comment in htmlEscaper. + r, w = utf8.DecodeRuneInString(s[i:]) + var repl string + switch { + case int(r) < len(lowUnicodeReplacementTable): + repl = lowUnicodeReplacementTable[r] + case int(r) < len(replacementTable) && replacementTable[r] != "": + repl = replacementTable[r] + case r == '\u2028': + repl = `\u2028` + case r == '\u2029': + repl = `\u2029` + default: + continue + } + if written == 0 { + b.Grow(len(s)) + } + b.WriteString(s[written:i]) + b.WriteString(repl) + written = i + w + } + if written == 0 { + return s + } + b.WriteString(s[written:]) + return b.String() +} + +var lowUnicodeReplacementTable = []string{ + 0: `\u0000`, 1: `\u0001`, 2: `\u0002`, 3: `\u0003`, 4: `\u0004`, 5: `\u0005`, 6: `\u0006`, + '\a': `\u0007`, + '\b': `\u0008`, + '\t': `\t`, + '\n': `\n`, + '\v': `\u000b`, // "\v" == "v" on IE 6. + '\f': `\f`, + '\r': `\r`, + 0xe: `\u000e`, 0xf: `\u000f`, 0x10: `\u0010`, 0x11: `\u0011`, 0x12: `\u0012`, 0x13: `\u0013`, + 0x14: `\u0014`, 0x15: `\u0015`, 0x16: `\u0016`, 0x17: `\u0017`, 0x18: `\u0018`, 0x19: `\u0019`, + 0x1a: `\u001a`, 0x1b: `\u001b`, 0x1c: `\u001c`, 0x1d: `\u001d`, 0x1e: `\u001e`, 0x1f: `\u001f`, +} + +var jsStrReplacementTable = []string{ + 0: `\u0000`, + '\t': `\t`, + '\n': `\n`, + '\v': `\u000b`, // "\v" == "v" on IE 6. + '\f': `\f`, + '\r': `\r`, + // Encode HTML specials as hex so the output can be embedded + // in HTML attributes without further encoding. + '"': `\u0022`, + '&': `\u0026`, + '\'': `\u0027`, + '+': `\u002b`, + '/': `\/`, + '<': `\u003c`, + '>': `\u003e`, + '\\': `\\`, +} + +// jsStrNormReplacementTable is like jsStrReplacementTable but does not +// overencode existing escapes since this table has no entry for `\`. +var jsStrNormReplacementTable = []string{ + 0: `\u0000`, + '\t': `\t`, + '\n': `\n`, + '\v': `\u000b`, // "\v" == "v" on IE 6. + '\f': `\f`, + '\r': `\r`, + // Encode HTML specials as hex so the output can be embedded + // in HTML attributes without further encoding. + '"': `\u0022`, + '&': `\u0026`, + '\'': `\u0027`, + '+': `\u002b`, + '/': `\/`, + '<': `\u003c`, + '>': `\u003e`, +} +var jsRegexpReplacementTable = []string{ + 0: `\u0000`, + '\t': `\t`, + '\n': `\n`, + '\v': `\u000b`, // "\v" == "v" on IE 6. + '\f': `\f`, + '\r': `\r`, + // Encode HTML specials as hex so the output can be embedded + // in HTML attributes without further encoding. + '"': `\u0022`, + '$': `\$`, + '&': `\u0026`, + '\'': `\u0027`, + '(': `\(`, + ')': `\)`, + '*': `\*`, + '+': `\u002b`, + '-': `\-`, + '.': `\.`, + '/': `\/`, + '<': `\u003c`, + '>': `\u003e`, + '?': `\?`, + '[': `\[`, + '\\': `\\`, + ']': `\]`, + '^': `\^`, + '{': `\{`, + '|': `\|`, + '}': `\}`, +} + +// isJSIdentPart reports whether the given rune is a JS identifier part. +// It does not handle all the non-Latin letters, joiners, and combining marks, +// but it does handle every codepoint that can occur in a numeric literal or +// a keyword. +func isJSIdentPart(r rune) bool { + switch { + case r == '$': + return true + case '0' <= r && r <= '9': + return true + case 'A' <= r && r <= 'Z': + return true + case r == '_': + return true + case 'a' <= r && r <= 'z': + return true + } + return false +} + +// isJSType reports whether the given MIME type should be considered JavaScript. +// +// It is used to determine whether a script tag with a type attribute is a javascript container. +func isJSType(mimeType string) bool { + // per + // https://www.w3.org/TR/html5/scripting-1.html#attr-script-type + // https://tools.ietf.org/html/rfc7231#section-3.1.1 + // https://tools.ietf.org/html/rfc4329#section-3 + // https://www.ietf.org/rfc/rfc4627.txt + // discard parameters + if i := strings.Index(mimeType, ";"); i >= 0 { + mimeType = mimeType[:i] + } + mimeType = strings.ToLower(mimeType) + mimeType = strings.TrimSpace(mimeType) + switch mimeType { + case + "application/ecmascript", + "application/javascript", + "application/json", + "application/ld+json", + "application/x-ecmascript", + "application/x-javascript", + "module", + "text/ecmascript", + "text/javascript", + "text/javascript1.0", + "text/javascript1.1", + "text/javascript1.2", + "text/javascript1.3", + "text/javascript1.4", + "text/javascript1.5", + "text/jscript", + "text/livescript", + "text/x-ecmascript", + "text/x-javascript": + return true + default: + return false + } +} diff --git a/src/html/template/js_test.go b/src/html/template/js_test.go new file mode 100644 index 0000000..d7ee47b --- /dev/null +++ b/src/html/template/js_test.go @@ -0,0 +1,423 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package template + +import ( + "bytes" + "math" + "strings" + "testing" +) + +func TestNextJsCtx(t *testing.T) { + tests := []struct { + jsCtx jsCtx + s string + }{ + // Statement terminators precede regexps. + {jsCtxRegexp, ";"}, + // This is not airtight. + // ({ valueOf: function () { return 1 } } / 2) + // is valid JavaScript but in practice, devs do not do this. + // A block followed by a statement starting with a RegExp is + // much more common: + // while (x) {...} /foo/.test(x) || panic() + {jsCtxRegexp, "}"}, + // But member, call, grouping, and array expression terminators + // precede div ops. + {jsCtxDivOp, ")"}, + {jsCtxDivOp, "]"}, + // At the start of a primary expression, array, or expression + // statement, expect a regexp. + {jsCtxRegexp, "("}, + {jsCtxRegexp, "["}, + {jsCtxRegexp, "{"}, + // Assignment operators precede regexps as do all exclusively + // prefix and binary operators. + {jsCtxRegexp, "="}, + {jsCtxRegexp, "+="}, + {jsCtxRegexp, "*="}, + {jsCtxRegexp, "*"}, + {jsCtxRegexp, "!"}, + // Whether the + or - is infix or prefix, it cannot precede a + // div op. + {jsCtxRegexp, "+"}, + {jsCtxRegexp, "-"}, + // An incr/decr op precedes a div operator. + // This is not airtight. In (g = ++/h/i) a regexp follows a + // pre-increment operator, but in practice devs do not try to + // increment or decrement regular expressions. + // (g++/h/i) where ++ is a postfix operator on g is much more + // common. + {jsCtxDivOp, "--"}, + {jsCtxDivOp, "++"}, + {jsCtxDivOp, "x--"}, + // When we have many dashes or pluses, then they are grouped + // left to right. + {jsCtxRegexp, "x---"}, // A postfix -- then a -. + // return followed by a slash returns the regexp literal or the + // slash starts a regexp literal in an expression statement that + // is dead code. + {jsCtxRegexp, "return"}, + {jsCtxRegexp, "return "}, + {jsCtxRegexp, "return\t"}, + {jsCtxRegexp, "return\n"}, + {jsCtxRegexp, "return\u2028"}, + // Identifiers can be divided and cannot validly be preceded by + // a regular expressions. Semicolon insertion cannot happen + // between an identifier and a regular expression on a new line + // because the one token lookahead for semicolon insertion has + // to conclude that it could be a div binary op and treat it as + // such. + {jsCtxDivOp, "x"}, + {jsCtxDivOp, "x "}, + {jsCtxDivOp, "x\t"}, + {jsCtxDivOp, "x\n"}, + {jsCtxDivOp, "x\u2028"}, + {jsCtxDivOp, "preturn"}, + // Numbers precede div ops. + {jsCtxDivOp, "0"}, + // Dots that are part of a number are div preceders. + {jsCtxDivOp, "0."}, + } + + for _, test := range tests { + if nextJSCtx([]byte(test.s), jsCtxRegexp) != test.jsCtx { + t.Errorf("want %s got %q", test.jsCtx, test.s) + } + if nextJSCtx([]byte(test.s), jsCtxDivOp) != test.jsCtx { + t.Errorf("want %s got %q", test.jsCtx, test.s) + } + } + + if nextJSCtx([]byte(" "), jsCtxRegexp) != jsCtxRegexp { + t.Error("Blank tokens") + } + + if nextJSCtx([]byte(" "), jsCtxDivOp) != jsCtxDivOp { + t.Error("Blank tokens") + } +} + +func TestJSValEscaper(t *testing.T) { + tests := []struct { + x interface{} + js string + }{ + {int(42), " 42 "}, + {uint(42), " 42 "}, + {int16(42), " 42 "}, + {uint16(42), " 42 "}, + {int32(-42), " -42 "}, + {uint32(42), " 42 "}, + {int16(-42), " -42 "}, + {uint16(42), " 42 "}, + {int64(-42), " -42 "}, + {uint64(42), " 42 "}, + {uint64(1) << 53, " 9007199254740992 "}, + // ulp(1 << 53) > 1 so this loses precision in JS + // but it is still a representable integer literal. + {uint64(1)<<53 + 1, " 9007199254740993 "}, + {float32(1.0), " 1 "}, + {float32(-1.0), " -1 "}, + {float32(0.5), " 0.5 "}, + {float32(-0.5), " -0.5 "}, + {float32(1.0) / float32(256), " 0.00390625 "}, + {float32(0), " 0 "}, + {math.Copysign(0, -1), " -0 "}, + {float64(1.0), " 1 "}, + {float64(-1.0), " -1 "}, + {float64(0.5), " 0.5 "}, + {float64(-0.5), " -0.5 "}, + {float64(0), " 0 "}, + {math.Copysign(0, -1), " -0 "}, + {"", `""`}, + {"foo", `"foo"`}, + // Newlines. + {"\r\n\u2028\u2029", `"\r\n\u2028\u2029"`}, + // "\v" == "v" on IE 6 so use "\u000b" instead. + {"\t\x0b", `"\t\u000b"`}, + {struct{ X, Y int }{1, 2}, `{"X":1,"Y":2}`}, + {[]interface{}{}, "[]"}, + {[]interface{}{42, "foo", nil}, `[42,"foo",null]`}, + {[]string{"<!--", "</script>", "-->"}, `["\u003c!--","\u003c/script\u003e","--\u003e"]`}, + {"<!--", `"\u003c!--"`}, + {"-->", `"--\u003e"`}, + {"<![CDATA[", `"\u003c![CDATA["`}, + {"]]>", `"]]\u003e"`}, + {"</script", `"\u003c/script"`}, + {"\U0001D11E", "\"\U0001D11E\""}, // or "\uD834\uDD1E" + {nil, " null "}, + } + + for _, test := range tests { + if js := jsValEscaper(test.x); js != test.js { + t.Errorf("%+v: want\n\t%q\ngot\n\t%q", test.x, test.js, js) + } + // Make sure that escaping corner cases are not broken + // by nesting. + a := []interface{}{test.x} + want := "[" + strings.TrimSpace(test.js) + "]" + if js := jsValEscaper(a); js != want { + t.Errorf("%+v: want\n\t%q\ngot\n\t%q", a, want, js) + } + } +} + +func TestJSStrEscaper(t *testing.T) { + tests := []struct { + x interface{} + esc string + }{ + {"", ``}, + {"foo", `foo`}, + {"\u0000", `\u0000`}, + {"\t", `\t`}, + {"\n", `\n`}, + {"\r", `\r`}, + {"\u2028", `\u2028`}, + {"\u2029", `\u2029`}, + {"\\", `\\`}, + {"\\n", `\\n`}, + {"foo\r\nbar", `foo\r\nbar`}, + // Preserve attribute boundaries. + {`"`, `\u0022`}, + {`'`, `\u0027`}, + // Allow embedding in HTML without further escaping. + {`&`, `\u0026amp;`}, + // Prevent breaking out of text node and element boundaries. + {"</script>", `\u003c\/script\u003e`}, + {"<![CDATA[", `\u003c![CDATA[`}, + {"]]>", `]]\u003e`}, + // https://dev.w3.org/html5/markup/aria/syntax.html#escaping-text-span + // "The text in style, script, title, and textarea elements + // must not have an escaping text span start that is not + // followed by an escaping text span end." + // Furthermore, spoofing an escaping text span end could lead + // to different interpretation of a </script> sequence otherwise + // masked by the escaping text span, and spoofing a start could + // allow regular text content to be interpreted as script + // allowing script execution via a combination of a JS string + // injection followed by an HTML text injection. + {"<!--", `\u003c!--`}, + {"-->", `--\u003e`}, + // From https://code.google.com/p/doctype/wiki/ArticleUtf7 + {"+ADw-script+AD4-alert(1)+ADw-/script+AD4-", + `\u002bADw-script\u002bAD4-alert(1)\u002bADw-\/script\u002bAD4-`, + }, + // Invalid UTF-8 sequence + {"foo\xA0bar", "foo\xA0bar"}, + // Invalid unicode scalar value. + {"foo\xed\xa0\x80bar", "foo\xed\xa0\x80bar"}, + } + + for _, test := range tests { + esc := jsStrEscaper(test.x) + if esc != test.esc { + t.Errorf("%q: want %q got %q", test.x, test.esc, esc) + } + } +} + +func TestJSRegexpEscaper(t *testing.T) { + tests := []struct { + x interface{} + esc string + }{ + {"", `(?:)`}, + {"foo", `foo`}, + {"\u0000", `\u0000`}, + {"\t", `\t`}, + {"\n", `\n`}, + {"\r", `\r`}, + {"\u2028", `\u2028`}, + {"\u2029", `\u2029`}, + {"\\", `\\`}, + {"\\n", `\\n`}, + {"foo\r\nbar", `foo\r\nbar`}, + // Preserve attribute boundaries. + {`"`, `\u0022`}, + {`'`, `\u0027`}, + // Allow embedding in HTML without further escaping. + {`&`, `\u0026amp;`}, + // Prevent breaking out of text node and element boundaries. + {"</script>", `\u003c\/script\u003e`}, + {"<![CDATA[", `\u003c!\[CDATA\[`}, + {"]]>", `\]\]\u003e`}, + // Escaping text spans. + {"<!--", `\u003c!\-\-`}, + {"-->", `\-\-\u003e`}, + {"*", `\*`}, + {"+", `\u002b`}, + {"?", `\?`}, + {"[](){}", `\[\]\(\)\{\}`}, + {"$foo|x.y", `\$foo\|x\.y`}, + {"x^y", `x\^y`}, + } + + for _, test := range tests { + esc := jsRegexpEscaper(test.x) + if esc != test.esc { + t.Errorf("%q: want %q got %q", test.x, test.esc, esc) + } + } +} + +func TestEscapersOnLower7AndSelectHighCodepoints(t *testing.T) { + input := ("\x00\x01\x02\x03\x04\x05\x06\x07\x08\t\n\x0b\x0c\r\x0e\x0f" + + "\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f" + + ` !"#$%&'()*+,-./` + + `0123456789:;<=>?` + + `@ABCDEFGHIJKLMNO` + + `PQRSTUVWXYZ[\]^_` + + "`abcdefghijklmno" + + "pqrstuvwxyz{|}~\x7f" + + "\u00A0\u0100\u2028\u2029\ufeff\U0001D11E") + + tests := []struct { + name string + escaper func(...interface{}) string + escaped string + }{ + { + "jsStrEscaper", + jsStrEscaper, + `\u0000\u0001\u0002\u0003\u0004\u0005\u0006\u0007` + + `\u0008\t\n\u000b\f\r\u000e\u000f` + + `\u0010\u0011\u0012\u0013\u0014\u0015\u0016\u0017` + + `\u0018\u0019\u001a\u001b\u001c\u001d\u001e\u001f` + + ` !\u0022#$%\u0026\u0027()*\u002b,-.\/` + + `0123456789:;\u003c=\u003e?` + + `@ABCDEFGHIJKLMNO` + + `PQRSTUVWXYZ[\\]^_` + + "`abcdefghijklmno" + + "pqrstuvwxyz{|}~\u007f" + + "\u00A0\u0100\\u2028\\u2029\ufeff\U0001D11E", + }, + { + "jsRegexpEscaper", + jsRegexpEscaper, + `\u0000\u0001\u0002\u0003\u0004\u0005\u0006\u0007` + + `\u0008\t\n\u000b\f\r\u000e\u000f` + + `\u0010\u0011\u0012\u0013\u0014\u0015\u0016\u0017` + + `\u0018\u0019\u001a\u001b\u001c\u001d\u001e\u001f` + + ` !\u0022#\$%\u0026\u0027\(\)\*\u002b,\-\.\/` + + `0123456789:;\u003c=\u003e\?` + + `@ABCDEFGHIJKLMNO` + + `PQRSTUVWXYZ\[\\\]\^_` + + "`abcdefghijklmno" + + `pqrstuvwxyz\{\|\}~` + "\u007f" + + "\u00A0\u0100\\u2028\\u2029\ufeff\U0001D11E", + }, + } + + for _, test := range tests { + if s := test.escaper(input); s != test.escaped { + t.Errorf("%s once: want\n\t%q\ngot\n\t%q", test.name, test.escaped, s) + continue + } + + // Escape it rune by rune to make sure that any + // fast-path checking does not break escaping. + var buf bytes.Buffer + for _, c := range input { + buf.WriteString(test.escaper(string(c))) + } + + if s := buf.String(); s != test.escaped { + t.Errorf("%s rune-wise: want\n\t%q\ngot\n\t%q", test.name, test.escaped, s) + continue + } + } +} + +func TestIsJsMimeType(t *testing.T) { + tests := []struct { + in string + out bool + }{ + {"application/javascript;version=1.8", true}, + {"application/javascript;version=1.8;foo=bar", true}, + {"application/javascript/version=1.8", false}, + {"text/javascript", true}, + {"application/json", true}, + {"application/ld+json", true}, + {"module", true}, + } + + for _, test := range tests { + if isJSType(test.in) != test.out { + t.Errorf("isJSType(%q) = %v, want %v", test.in, !test.out, test.out) + } + } +} + +func BenchmarkJSValEscaperWithNum(b *testing.B) { + for i := 0; i < b.N; i++ { + jsValEscaper(3.141592654) + } +} + +func BenchmarkJSValEscaperWithStr(b *testing.B) { + for i := 0; i < b.N; i++ { + jsValEscaper("The <i>quick</i>,\r\n<span style='color:brown'>brown</span> fox jumps\u2028over the <canine class=\"lazy\">dog</canine>") + } +} + +func BenchmarkJSValEscaperWithStrNoSpecials(b *testing.B) { + for i := 0; i < b.N; i++ { + jsValEscaper("The quick, brown fox jumps over the lazy dog") + } +} + +func BenchmarkJSValEscaperWithObj(b *testing.B) { + o := struct { + S string + N int + }{ + "The <i>quick</i>,\r\n<span style='color:brown'>brown</span> fox jumps\u2028over the <canine class=\"lazy\">dog</canine>\u2028", + 42, + } + for i := 0; i < b.N; i++ { + jsValEscaper(o) + } +} + +func BenchmarkJSValEscaperWithObjNoSpecials(b *testing.B) { + o := struct { + S string + N int + }{ + "The quick, brown fox jumps over the lazy dog", + 42, + } + for i := 0; i < b.N; i++ { + jsValEscaper(o) + } +} + +func BenchmarkJSStrEscaperNoSpecials(b *testing.B) { + for i := 0; i < b.N; i++ { + jsStrEscaper("The quick, brown fox jumps over the lazy dog.") + } +} + +func BenchmarkJSStrEscaper(b *testing.B) { + for i := 0; i < b.N; i++ { + jsStrEscaper("The <i>quick</i>,\r\n<span style='color:brown'>brown</span> fox jumps\u2028over the <canine class=\"lazy\">dog</canine>") + } +} + +func BenchmarkJSRegexpEscaperNoSpecials(b *testing.B) { + for i := 0; i < b.N; i++ { + jsRegexpEscaper("The quick, brown fox jumps over the lazy dog") + } +} + +func BenchmarkJSRegexpEscaper(b *testing.B) { + for i := 0; i < b.N; i++ { + jsRegexpEscaper("The <i>quick</i>,\r\n<span style='color:brown'>brown</span> fox jumps\u2028over the <canine class=\"lazy\">dog</canine>") + } +} diff --git a/src/html/template/jsctx_string.go b/src/html/template/jsctx_string.go new file mode 100644 index 0000000..dd1d87e --- /dev/null +++ b/src/html/template/jsctx_string.go @@ -0,0 +1,16 @@ +// Code generated by "stringer -type jsCtx"; DO NOT EDIT. + +package template + +import "strconv" + +const _jsCtx_name = "jsCtxRegexpjsCtxDivOpjsCtxUnknown" + +var _jsCtx_index = [...]uint8{0, 11, 21, 33} + +func (i jsCtx) String() string { + if i >= jsCtx(len(_jsCtx_index)-1) { + return "jsCtx(" + strconv.FormatInt(int64(i), 10) + ")" + } + return _jsCtx_name[_jsCtx_index[i]:_jsCtx_index[i+1]] +} diff --git a/src/html/template/multi_test.go b/src/html/template/multi_test.go new file mode 100644 index 0000000..6535ab6 --- /dev/null +++ b/src/html/template/multi_test.go @@ -0,0 +1,289 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// Tests for multiple-template execution, copied from text/template. + +package template + +import ( + "archive/zip" + "bytes" + "os" + "testing" + "text/template/parse" +) + +var multiExecTests = []execTest{ + {"empty", "", "", nil, true}, + {"text", "some text", "some text", nil, true}, + {"invoke x", `{{template "x" .SI}}`, "TEXT", tVal, true}, + {"invoke x no args", `{{template "x"}}`, "TEXT", tVal, true}, + {"invoke dot int", `{{template "dot" .I}}`, "17", tVal, true}, + {"invoke dot []int", `{{template "dot" .SI}}`, "[3 4 5]", tVal, true}, + {"invoke dotV", `{{template "dotV" .U}}`, "v", tVal, true}, + {"invoke nested int", `{{template "nested" .I}}`, "17", tVal, true}, + {"variable declared by template", `{{template "nested" $x:=.SI}},{{index $x 1}}`, "[3 4 5],4", tVal, true}, + + // User-defined function: test argument evaluator. + {"testFunc literal", `{{oneArg "joe"}}`, "oneArg=joe", tVal, true}, + {"testFunc .", `{{oneArg .}}`, "oneArg=joe", "joe", true}, +} + +// These strings are also in testdata/*. +const multiText1 = ` + {{define "x"}}TEXT{{end}} + {{define "dotV"}}{{.V}}{{end}} +` + +const multiText2 = ` + {{define "dot"}}{{.}}{{end}} + {{define "nested"}}{{template "dot" .}}{{end}} +` + +func TestMultiExecute(t *testing.T) { + // Declare a couple of templates first. + template, err := New("root").Parse(multiText1) + if err != nil { + t.Fatalf("parse error for 1: %s", err) + } + _, err = template.Parse(multiText2) + if err != nil { + t.Fatalf("parse error for 2: %s", err) + } + testExecute(multiExecTests, template, t) +} + +func TestParseFiles(t *testing.T) { + _, err := ParseFiles("DOES NOT EXIST") + if err == nil { + t.Error("expected error for non-existent file; got none") + } + template := New("root") + _, err = template.ParseFiles("testdata/file1.tmpl", "testdata/file2.tmpl") + if err != nil { + t.Fatalf("error parsing files: %v", err) + } + testExecute(multiExecTests, template, t) +} + +func TestParseGlob(t *testing.T) { + _, err := ParseGlob("DOES NOT EXIST") + if err == nil { + t.Error("expected error for non-existent file; got none") + } + _, err = New("error").ParseGlob("[x") + if err == nil { + t.Error("expected error for bad pattern; got none") + } + template := New("root") + _, err = template.ParseGlob("testdata/file*.tmpl") + if err != nil { + t.Fatalf("error parsing files: %v", err) + } + testExecute(multiExecTests, template, t) +} + +func TestParseFS(t *testing.T) { + fs := os.DirFS("testdata") + + { + _, err := ParseFS(fs, "DOES NOT EXIST") + if err == nil { + t.Error("expected error for non-existent file; got none") + } + } + + { + template := New("root") + _, err := template.ParseFS(fs, "file1.tmpl", "file2.tmpl") + if err != nil { + t.Fatalf("error parsing files: %v", err) + } + testExecute(multiExecTests, template, t) + } + + { + template := New("root") + _, err := template.ParseFS(fs, "file*.tmpl") + if err != nil { + t.Fatalf("error parsing files: %v", err) + } + testExecute(multiExecTests, template, t) + } +} + +// In these tests, actual content (not just template definitions) comes from the parsed files. + +var templateFileExecTests = []execTest{ + {"test", `{{template "tmpl1.tmpl"}}{{template "tmpl2.tmpl"}}`, "template1\n\ny\ntemplate2\n\nx\n", 0, true}, +} + +func TestParseFilesWithData(t *testing.T) { + template, err := New("root").ParseFiles("testdata/tmpl1.tmpl", "testdata/tmpl2.tmpl") + if err != nil { + t.Fatalf("error parsing files: %v", err) + } + testExecute(templateFileExecTests, template, t) +} + +func TestParseGlobWithData(t *testing.T) { + template, err := New("root").ParseGlob("testdata/tmpl*.tmpl") + if err != nil { + t.Fatalf("error parsing files: %v", err) + } + testExecute(templateFileExecTests, template, t) +} + +func TestParseZipFS(t *testing.T) { + z, err := zip.OpenReader("testdata/fs.zip") + if err != nil { + t.Fatalf("error parsing zip: %v", err) + } + template, err := New("root").ParseFS(z, "tmpl*.tmpl") + if err != nil { + t.Fatalf("error parsing files: %v", err) + } + testExecute(templateFileExecTests, template, t) +} + +const ( + cloneText1 = `{{define "a"}}{{template "b"}}{{template "c"}}{{end}}` + cloneText2 = `{{define "b"}}b{{end}}` + cloneText3 = `{{define "c"}}root{{end}}` + cloneText4 = `{{define "c"}}clone{{end}}` +) + +// Issue 7032 +func TestAddParseTreeToUnparsedTemplate(t *testing.T) { + master := "{{define \"master\"}}{{end}}" + tmpl := New("master") + tree, err := parse.Parse("master", master, "", "", nil) + if err != nil { + t.Fatalf("unexpected parse err: %v", err) + } + masterTree := tree["master"] + tmpl.AddParseTree("master", masterTree) // used to panic +} + +func TestRedefinition(t *testing.T) { + var tmpl *Template + var err error + if tmpl, err = New("tmpl1").Parse(`{{define "test"}}foo{{end}}`); err != nil { + t.Fatalf("parse 1: %v", err) + } + if _, err = tmpl.Parse(`{{define "test"}}bar{{end}}`); err != nil { + t.Fatalf("got error %v, expected nil", err) + } + if _, err = tmpl.New("tmpl2").Parse(`{{define "test"}}bar{{end}}`); err != nil { + t.Fatalf("got error %v, expected nil", err) + } +} + +// Issue 10879 +func TestEmptyTemplateCloneCrash(t *testing.T) { + t1 := New("base") + t1.Clone() // used to panic +} + +// Issue 10910, 10926 +func TestTemplateLookUp(t *testing.T) { + t.Skip("broken on html/template") // TODO + t1 := New("foo") + if t1.Lookup("foo") != nil { + t.Error("Lookup returned non-nil value for undefined template foo") + } + t1.New("bar") + if t1.Lookup("bar") != nil { + t.Error("Lookup returned non-nil value for undefined template bar") + } + t1.Parse(`{{define "foo"}}test{{end}}`) + if t1.Lookup("foo") == nil { + t.Error("Lookup returned nil value for defined template") + } +} + +func TestParse(t *testing.T) { + // In multiple calls to Parse with the same receiver template, only one call + // can contain text other than space, comments, and template definitions + t1 := New("test") + if _, err := t1.Parse(`{{define "test"}}{{end}}`); err != nil { + t.Fatalf("parsing test: %s", err) + } + if _, err := t1.Parse(`{{define "test"}}{{/* this is a comment */}}{{end}}`); err != nil { + t.Fatalf("parsing test: %s", err) + } + if _, err := t1.Parse(`{{define "test"}}foo{{end}}`); err != nil { + t.Fatalf("parsing test: %s", err) + } +} + +func TestEmptyTemplate(t *testing.T) { + cases := []struct { + defn []string + in string + want string + }{ + {[]string{"x", "y"}, "", "y"}, + {[]string{""}, "once", ""}, + {[]string{"", ""}, "twice", ""}, + {[]string{"{{.}}", "{{.}}"}, "twice", "twice"}, + {[]string{"{{/* a comment */}}", "{{/* a comment */}}"}, "comment", ""}, + {[]string{"{{.}}", ""}, "twice", "twice"}, // TODO: should want "" not "twice" + } + + for i, c := range cases { + root := New("root") + + var ( + m *Template + err error + ) + for _, d := range c.defn { + m, err = root.New(c.in).Parse(d) + if err != nil { + t.Fatal(err) + } + } + buf := &bytes.Buffer{} + if err := m.Execute(buf, c.in); err != nil { + t.Error(i, err) + continue + } + if buf.String() != c.want { + t.Errorf("expected string %q: got %q", c.want, buf.String()) + } + } +} + +// Issue 19249 was a regression in 1.8 caused by the handling of empty +// templates added in that release, which got different answers depending +// on the order templates appeared in the internal map. +func TestIssue19294(t *testing.T) { + // The empty block in "xhtml" should be replaced during execution + // by the contents of "stylesheet", but if the internal map associating + // names with templates is built in the wrong order, the empty block + // looks non-empty and this doesn't happen. + var inlined = map[string]string{ + "stylesheet": `{{define "stylesheet"}}stylesheet{{end}}`, + "xhtml": `{{block "stylesheet" .}}{{end}}`, + } + all := []string{"stylesheet", "xhtml"} + for i := 0; i < 100; i++ { + res, err := New("title.xhtml").Parse(`{{template "xhtml" .}}`) + if err != nil { + t.Fatal(err) + } + for _, name := range all { + _, err := res.New(name).Parse(inlined[name]) + if err != nil { + t.Fatal(err) + } + } + var buf bytes.Buffer + res.Execute(&buf, 0) + if buf.String() != "stylesheet" { + t.Fatalf("iteration %d: got %q; expected %q", i, buf.String(), "stylesheet") + } + } +} diff --git a/src/html/template/state_string.go b/src/html/template/state_string.go new file mode 100644 index 0000000..05104be --- /dev/null +++ b/src/html/template/state_string.go @@ -0,0 +1,16 @@ +// Code generated by "stringer -type state"; DO NOT EDIT. + +package template + +import "strconv" + +const _state_name = "stateTextstateTagstateAttrNamestateAfterNamestateBeforeValuestateHTMLCmtstateRCDATAstateAttrstateURLstateSrcsetstateJSstateJSDqStrstateJSSqStrstateJSRegexpstateJSBlockCmtstateJSLineCmtstateCSSstateCSSDqStrstateCSSSqStrstateCSSDqURLstateCSSSqURLstateCSSURLstateCSSBlockCmtstateCSSLineCmtstateError" + +var _state_index = [...]uint16{0, 9, 17, 30, 44, 60, 72, 83, 92, 100, 111, 118, 130, 142, 155, 170, 184, 192, 205, 218, 231, 244, 255, 271, 286, 296} + +func (i state) String() string { + if i >= state(len(_state_index)-1) { + return "state(" + strconv.FormatInt(int64(i), 10) + ")" + } + return _state_name[_state_index[i]:_state_index[i+1]] +} diff --git a/src/html/template/template.go b/src/html/template/template.go new file mode 100644 index 0000000..69312d3 --- /dev/null +++ b/src/html/template/template.go @@ -0,0 +1,536 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package template + +import ( + "fmt" + "io" + "io/fs" + "os" + "path" + "path/filepath" + "sync" + "text/template" + "text/template/parse" +) + +// Template is a specialized Template from "text/template" that produces a safe +// HTML document fragment. +type Template struct { + // Sticky error if escaping fails, or escapeOK if succeeded. + escapeErr error + // We could embed the text/template field, but it's safer not to because + // we need to keep our version of the name space and the underlying + // template's in sync. + text *template.Template + // The underlying template's parse tree, updated to be HTML-safe. + Tree *parse.Tree + *nameSpace // common to all associated templates +} + +// escapeOK is a sentinel value used to indicate valid escaping. +var escapeOK = fmt.Errorf("template escaped correctly") + +// nameSpace is the data structure shared by all templates in an association. +type nameSpace struct { + mu sync.Mutex + set map[string]*Template + escaped bool + esc escaper +} + +// Templates returns a slice of the templates associated with t, including t +// itself. +func (t *Template) Templates() []*Template { + ns := t.nameSpace + ns.mu.Lock() + defer ns.mu.Unlock() + // Return a slice so we don't expose the map. + m := make([]*Template, 0, len(ns.set)) + for _, v := range ns.set { + m = append(m, v) + } + return m +} + +// Option sets options for the template. Options are described by +// strings, either a simple string or "key=value". There can be at +// most one equals sign in an option string. If the option string +// is unrecognized or otherwise invalid, Option panics. +// +// Known options: +// +// missingkey: Control the behavior during execution if a map is +// indexed with a key that is not present in the map. +// "missingkey=default" or "missingkey=invalid" +// The default behavior: Do nothing and continue execution. +// If printed, the result of the index operation is the string +// "<no value>". +// "missingkey=zero" +// The operation returns the zero value for the map type's element. +// "missingkey=error" +// Execution stops immediately with an error. +// +func (t *Template) Option(opt ...string) *Template { + t.text.Option(opt...) + return t +} + +// checkCanParse checks whether it is OK to parse templates. +// If not, it returns an error. +func (t *Template) checkCanParse() error { + if t == nil { + return nil + } + t.nameSpace.mu.Lock() + defer t.nameSpace.mu.Unlock() + if t.nameSpace.escaped { + return fmt.Errorf("html/template: cannot Parse after Execute") + } + return nil +} + +// escape escapes all associated templates. +func (t *Template) escape() error { + t.nameSpace.mu.Lock() + defer t.nameSpace.mu.Unlock() + t.nameSpace.escaped = true + if t.escapeErr == nil { + if t.Tree == nil { + return fmt.Errorf("template: %q is an incomplete or empty template", t.Name()) + } + if err := escapeTemplate(t, t.text.Root, t.Name()); err != nil { + return err + } + } else if t.escapeErr != escapeOK { + return t.escapeErr + } + return nil +} + +// Execute applies a parsed template to the specified data object, +// writing the output to wr. +// If an error occurs executing the template or writing its output, +// execution stops, but partial results may already have been written to +// the output writer. +// A template may be executed safely in parallel, although if parallel +// executions share a Writer the output may be interleaved. +func (t *Template) Execute(wr io.Writer, data interface{}) error { + if err := t.escape(); err != nil { + return err + } + return t.text.Execute(wr, data) +} + +// ExecuteTemplate applies the template associated with t that has the given +// name to the specified data object and writes the output to wr. +// If an error occurs executing the template or writing its output, +// execution stops, but partial results may already have been written to +// the output writer. +// A template may be executed safely in parallel, although if parallel +// executions share a Writer the output may be interleaved. +func (t *Template) ExecuteTemplate(wr io.Writer, name string, data interface{}) error { + tmpl, err := t.lookupAndEscapeTemplate(name) + if err != nil { + return err + } + return tmpl.text.Execute(wr, data) +} + +// lookupAndEscapeTemplate guarantees that the template with the given name +// is escaped, or returns an error if it cannot be. It returns the named +// template. +func (t *Template) lookupAndEscapeTemplate(name string) (tmpl *Template, err error) { + t.nameSpace.mu.Lock() + defer t.nameSpace.mu.Unlock() + t.nameSpace.escaped = true + tmpl = t.set[name] + if tmpl == nil { + return nil, fmt.Errorf("html/template: %q is undefined", name) + } + if tmpl.escapeErr != nil && tmpl.escapeErr != escapeOK { + return nil, tmpl.escapeErr + } + if tmpl.text.Tree == nil || tmpl.text.Root == nil { + return nil, fmt.Errorf("html/template: %q is an incomplete template", name) + } + if t.text.Lookup(name) == nil { + panic("html/template internal error: template escaping out of sync") + } + if tmpl.escapeErr == nil { + err = escapeTemplate(tmpl, tmpl.text.Root, name) + } + return tmpl, err +} + +// DefinedTemplates returns a string listing the defined templates, +// prefixed by the string "; defined templates are: ". If there are none, +// it returns the empty string. Used to generate an error message. +func (t *Template) DefinedTemplates() string { + return t.text.DefinedTemplates() +} + +// Parse parses text as a template body for t. +// Named template definitions ({{define ...}} or {{block ...}} statements) in text +// define additional templates associated with t and are removed from the +// definition of t itself. +// +// Templates can be redefined in successive calls to Parse, +// before the first use of Execute on t or any associated template. +// A template definition with a body containing only white space and comments +// is considered empty and will not replace an existing template's body. +// This allows using Parse to add new named template definitions without +// overwriting the main template body. +func (t *Template) Parse(text string) (*Template, error) { + if err := t.checkCanParse(); err != nil { + return nil, err + } + + ret, err := t.text.Parse(text) + if err != nil { + return nil, err + } + + // In general, all the named templates might have changed underfoot. + // Regardless, some new ones may have been defined. + // The template.Template set has been updated; update ours. + t.nameSpace.mu.Lock() + defer t.nameSpace.mu.Unlock() + for _, v := range ret.Templates() { + name := v.Name() + tmpl := t.set[name] + if tmpl == nil { + tmpl = t.new(name) + } + tmpl.text = v + tmpl.Tree = v.Tree + } + return t, nil +} + +// AddParseTree creates a new template with the name and parse tree +// and associates it with t. +// +// It returns an error if t or any associated template has already been executed. +func (t *Template) AddParseTree(name string, tree *parse.Tree) (*Template, error) { + if err := t.checkCanParse(); err != nil { + return nil, err + } + + t.nameSpace.mu.Lock() + defer t.nameSpace.mu.Unlock() + text, err := t.text.AddParseTree(name, tree) + if err != nil { + return nil, err + } + ret := &Template{ + nil, + text, + text.Tree, + t.nameSpace, + } + t.set[name] = ret + return ret, nil +} + +// Clone returns a duplicate of the template, including all associated +// templates. The actual representation is not copied, but the name space of +// associated templates is, so further calls to Parse in the copy will add +// templates to the copy but not to the original. Clone can be used to prepare +// common templates and use them with variant definitions for other templates +// by adding the variants after the clone is made. +// +// It returns an error if t has already been executed. +func (t *Template) Clone() (*Template, error) { + t.nameSpace.mu.Lock() + defer t.nameSpace.mu.Unlock() + if t.escapeErr != nil { + return nil, fmt.Errorf("html/template: cannot Clone %q after it has executed", t.Name()) + } + textClone, err := t.text.Clone() + if err != nil { + return nil, err + } + ns := &nameSpace{set: make(map[string]*Template)} + ns.esc = makeEscaper(ns) + ret := &Template{ + nil, + textClone, + textClone.Tree, + ns, + } + ret.set[ret.Name()] = ret + for _, x := range textClone.Templates() { + name := x.Name() + src := t.set[name] + if src == nil || src.escapeErr != nil { + return nil, fmt.Errorf("html/template: cannot Clone %q after it has executed", t.Name()) + } + x.Tree = x.Tree.Copy() + ret.set[name] = &Template{ + nil, + x, + x.Tree, + ret.nameSpace, + } + } + // Return the template associated with the name of this template. + return ret.set[ret.Name()], nil +} + +// New allocates a new HTML template with the given name. +func New(name string) *Template { + ns := &nameSpace{set: make(map[string]*Template)} + ns.esc = makeEscaper(ns) + tmpl := &Template{ + nil, + template.New(name), + nil, + ns, + } + tmpl.set[name] = tmpl + return tmpl +} + +// New allocates a new HTML template associated with the given one +// and with the same delimiters. The association, which is transitive, +// allows one template to invoke another with a {{template}} action. +// +// If a template with the given name already exists, the new HTML template +// will replace it. The existing template will be reset and disassociated with +// t. +func (t *Template) New(name string) *Template { + t.nameSpace.mu.Lock() + defer t.nameSpace.mu.Unlock() + return t.new(name) +} + +// new is the implementation of New, without the lock. +func (t *Template) new(name string) *Template { + tmpl := &Template{ + nil, + t.text.New(name), + nil, + t.nameSpace, + } + if existing, ok := tmpl.set[name]; ok { + emptyTmpl := New(existing.Name()) + *existing = *emptyTmpl + } + tmpl.set[name] = tmpl + return tmpl +} + +// Name returns the name of the template. +func (t *Template) Name() string { + return t.text.Name() +} + +// FuncMap is the type of the map defining the mapping from names to +// functions. Each function must have either a single return value, or two +// return values of which the second has type error. In that case, if the +// second (error) argument evaluates to non-nil during execution, execution +// terminates and Execute returns that error. FuncMap has the same base type +// as FuncMap in "text/template", copied here so clients need not import +// "text/template". +type FuncMap map[string]interface{} + +// Funcs adds the elements of the argument map to the template's function map. +// It must be called before the template is parsed. +// It panics if a value in the map is not a function with appropriate return +// type. However, it is legal to overwrite elements of the map. The return +// value is the template, so calls can be chained. +func (t *Template) Funcs(funcMap FuncMap) *Template { + t.text.Funcs(template.FuncMap(funcMap)) + return t +} + +// Delims sets the action delimiters to the specified strings, to be used in +// subsequent calls to Parse, ParseFiles, or ParseGlob. Nested template +// definitions will inherit the settings. An empty delimiter stands for the +// corresponding default: {{ or }}. +// The return value is the template, so calls can be chained. +func (t *Template) Delims(left, right string) *Template { + t.text.Delims(left, right) + return t +} + +// Lookup returns the template with the given name that is associated with t, +// or nil if there is no such template. +func (t *Template) Lookup(name string) *Template { + t.nameSpace.mu.Lock() + defer t.nameSpace.mu.Unlock() + return t.set[name] +} + +// Must is a helper that wraps a call to a function returning (*Template, error) +// and panics if the error is non-nil. It is intended for use in variable initializations +// such as +// var t = template.Must(template.New("name").Parse("html")) +func Must(t *Template, err error) *Template { + if err != nil { + panic(err) + } + return t +} + +// ParseFiles creates a new Template and parses the template definitions from +// the named files. The returned template's name will have the (base) name and +// (parsed) contents of the first file. There must be at least one file. +// If an error occurs, parsing stops and the returned *Template is nil. +// +// When parsing multiple files with the same name in different directories, +// the last one mentioned will be the one that results. +// For instance, ParseFiles("a/foo", "b/foo") stores "b/foo" as the template +// named "foo", while "a/foo" is unavailable. +func ParseFiles(filenames ...string) (*Template, error) { + return parseFiles(nil, readFileOS, filenames...) +} + +// ParseFiles parses the named files and associates the resulting templates with +// t. If an error occurs, parsing stops and the returned template is nil; +// otherwise it is t. There must be at least one file. +// +// When parsing multiple files with the same name in different directories, +// the last one mentioned will be the one that results. +// +// ParseFiles returns an error if t or any associated template has already been executed. +func (t *Template) ParseFiles(filenames ...string) (*Template, error) { + return parseFiles(t, readFileOS, filenames...) +} + +// parseFiles is the helper for the method and function. If the argument +// template is nil, it is created from the first file. +func parseFiles(t *Template, readFile func(string) (string, []byte, error), filenames ...string) (*Template, error) { + if err := t.checkCanParse(); err != nil { + return nil, err + } + + if len(filenames) == 0 { + // Not really a problem, but be consistent. + return nil, fmt.Errorf("html/template: no files named in call to ParseFiles") + } + for _, filename := range filenames { + name, b, err := readFile(filename) + if err != nil { + return nil, err + } + s := string(b) + // First template becomes return value if not already defined, + // and we use that one for subsequent New calls to associate + // all the templates together. Also, if this file has the same name + // as t, this file becomes the contents of t, so + // t, err := New(name).Funcs(xxx).ParseFiles(name) + // works. Otherwise we create a new template associated with t. + var tmpl *Template + if t == nil { + t = New(name) + } + if name == t.Name() { + tmpl = t + } else { + tmpl = t.New(name) + } + _, err = tmpl.Parse(s) + if err != nil { + return nil, err + } + } + return t, nil +} + +// ParseGlob creates a new Template and parses the template definitions from +// the files identified by the pattern. The files are matched according to the +// semantics of filepath.Match, and the pattern must match at least one file. +// The returned template will have the (base) name and (parsed) contents of the +// first file matched by the pattern. ParseGlob is equivalent to calling +// ParseFiles with the list of files matched by the pattern. +// +// When parsing multiple files with the same name in different directories, +// the last one mentioned will be the one that results. +func ParseGlob(pattern string) (*Template, error) { + return parseGlob(nil, pattern) +} + +// ParseGlob parses the template definitions in the files identified by the +// pattern and associates the resulting templates with t. The files are matched +// according to the semantics of filepath.Match, and the pattern must match at +// least one file. ParseGlob is equivalent to calling t.ParseFiles with the +// list of files matched by the pattern. +// +// When parsing multiple files with the same name in different directories, +// the last one mentioned will be the one that results. +// +// ParseGlob returns an error if t or any associated template has already been executed. +func (t *Template) ParseGlob(pattern string) (*Template, error) { + return parseGlob(t, pattern) +} + +// parseGlob is the implementation of the function and method ParseGlob. +func parseGlob(t *Template, pattern string) (*Template, error) { + if err := t.checkCanParse(); err != nil { + return nil, err + } + filenames, err := filepath.Glob(pattern) + if err != nil { + return nil, err + } + if len(filenames) == 0 { + return nil, fmt.Errorf("html/template: pattern matches no files: %#q", pattern) + } + return parseFiles(t, readFileOS, filenames...) +} + +// IsTrue reports whether the value is 'true', in the sense of not the zero of its type, +// and whether the value has a meaningful truth value. This is the definition of +// truth used by if and other such actions. +func IsTrue(val interface{}) (truth, ok bool) { + return template.IsTrue(val) +} + +// ParseFS is like ParseFiles or ParseGlob but reads from the file system fs +// instead of the host operating system's file system. +// It accepts a list of glob patterns. +// (Note that most file names serve as glob patterns matching only themselves.) +func ParseFS(fs fs.FS, patterns ...string) (*Template, error) { + return parseFS(nil, fs, patterns) +} + +// ParseFS is like ParseFiles or ParseGlob but reads from the file system fs +// instead of the host operating system's file system. +// It accepts a list of glob patterns. +// (Note that most file names serve as glob patterns matching only themselves.) +func (t *Template) ParseFS(fs fs.FS, patterns ...string) (*Template, error) { + return parseFS(t, fs, patterns) +} + +func parseFS(t *Template, fsys fs.FS, patterns []string) (*Template, error) { + var filenames []string + for _, pattern := range patterns { + list, err := fs.Glob(fsys, pattern) + if err != nil { + return nil, err + } + if len(list) == 0 { + return nil, fmt.Errorf("template: pattern matches no files: %#q", pattern) + } + filenames = append(filenames, list...) + } + return parseFiles(t, readFileFS(fsys), filenames...) +} + +func readFileOS(file string) (name string, b []byte, err error) { + name = filepath.Base(file) + b, err = os.ReadFile(file) + return +} + +func readFileFS(fsys fs.FS) func(string) (string, []byte, error) { + return func(file string) (name string, b []byte, err error) { + name = path.Base(file) + b, err = fs.ReadFile(fsys, file) + return + } +} diff --git a/src/html/template/template_test.go b/src/html/template/template_test.go new file mode 100644 index 0000000..1f2c888 --- /dev/null +++ b/src/html/template/template_test.go @@ -0,0 +1,218 @@ +// Copyright 2016 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package template_test + +import ( + "bytes" + "encoding/json" + . "html/template" + "strings" + "testing" + "text/template/parse" +) + +func TestTemplateClone(t *testing.T) { + // https://golang.org/issue/12996 + orig := New("name") + clone, err := orig.Clone() + if err != nil { + t.Fatal(err) + } + if len(clone.Templates()) != len(orig.Templates()) { + t.Fatalf("Invalid length of t.Clone().Templates()") + } + + const want = "stuff" + parsed := Must(clone.Parse(want)) + var buf bytes.Buffer + err = parsed.Execute(&buf, nil) + if err != nil { + t.Fatal(err) + } + if got := buf.String(); got != want { + t.Fatalf("got %q; want %q", got, want) + } +} + +func TestRedefineNonEmptyAfterExecution(t *testing.T) { + c := newTestCase(t) + c.mustParse(c.root, `foo`) + c.mustExecute(c.root, nil, "foo") + c.mustNotParse(c.root, `bar`) +} + +func TestRedefineEmptyAfterExecution(t *testing.T) { + c := newTestCase(t) + c.mustParse(c.root, ``) + c.mustExecute(c.root, nil, "") + c.mustNotParse(c.root, `foo`) + c.mustExecute(c.root, nil, "") +} + +func TestRedefineAfterNonExecution(t *testing.T) { + c := newTestCase(t) + c.mustParse(c.root, `{{if .}}<{{template "X"}}>{{end}}{{define "X"}}foo{{end}}`) + c.mustExecute(c.root, 0, "") + c.mustNotParse(c.root, `{{define "X"}}bar{{end}}`) + c.mustExecute(c.root, 1, "<foo>") +} + +func TestRedefineAfterNamedExecution(t *testing.T) { + c := newTestCase(t) + c.mustParse(c.root, `<{{template "X" .}}>{{define "X"}}foo{{end}}`) + c.mustExecute(c.root, nil, "<foo>") + c.mustNotParse(c.root, `{{define "X"}}bar{{end}}`) + c.mustExecute(c.root, nil, "<foo>") +} + +func TestRedefineNestedByNameAfterExecution(t *testing.T) { + c := newTestCase(t) + c.mustParse(c.root, `{{define "X"}}foo{{end}}`) + c.mustExecute(c.lookup("X"), nil, "foo") + c.mustNotParse(c.root, `{{define "X"}}bar{{end}}`) + c.mustExecute(c.lookup("X"), nil, "foo") +} + +func TestRedefineNestedByTemplateAfterExecution(t *testing.T) { + c := newTestCase(t) + c.mustParse(c.root, `{{define "X"}}foo{{end}}`) + c.mustExecute(c.lookup("X"), nil, "foo") + c.mustNotParse(c.lookup("X"), `bar`) + c.mustExecute(c.lookup("X"), nil, "foo") +} + +func TestRedefineSafety(t *testing.T) { + c := newTestCase(t) + c.mustParse(c.root, `<html><a href="{{template "X"}}">{{define "X"}}{{end}}`) + c.mustExecute(c.root, nil, `<html><a href="">`) + // Note: Every version of Go prior to Go 1.8 accepted the redefinition of "X" + // on the next line, but luckily kept it from being used in the outer template. + // Now we reject it, which makes clearer that we're not going to use it. + c.mustNotParse(c.root, `{{define "X"}}" bar="baz{{end}}`) + c.mustExecute(c.root, nil, `<html><a href="">`) +} + +func TestRedefineTopUse(t *testing.T) { + c := newTestCase(t) + c.mustParse(c.root, `{{template "X"}}{{.}}{{define "X"}}{{end}}`) + c.mustExecute(c.root, 42, `42`) + c.mustNotParse(c.root, `{{define "X"}}<script>{{end}}`) + c.mustExecute(c.root, 42, `42`) +} + +func TestRedefineOtherParsers(t *testing.T) { + c := newTestCase(t) + c.mustParse(c.root, ``) + c.mustExecute(c.root, nil, ``) + if _, err := c.root.ParseFiles("no.template"); err == nil || !strings.Contains(err.Error(), "Execute") { + t.Errorf("ParseFiles: %v\nwanted error about already having Executed", err) + } + if _, err := c.root.ParseGlob("*.no.template"); err == nil || !strings.Contains(err.Error(), "Execute") { + t.Errorf("ParseGlob: %v\nwanted error about already having Executed", err) + } + if _, err := c.root.AddParseTree("t1", c.root.Tree); err == nil || !strings.Contains(err.Error(), "Execute") { + t.Errorf("AddParseTree: %v\nwanted error about already having Executed", err) + } +} + +func TestNumbers(t *testing.T) { + c := newTestCase(t) + c.mustParse(c.root, `{{print 1_2.3_4}} {{print 0x0_1.e_0p+02}}`) + c.mustExecute(c.root, nil, "12.34 7.5") +} + +func TestStringsInScriptsWithJsonContentTypeAreCorrectlyEscaped(t *testing.T) { + // See #33671 and #37634 for more context on this. + tests := []struct{ name, in string }{ + {"empty", ""}, + {"invalid", string(rune(-1))}, + {"null", "\u0000"}, + {"unit separator", "\u001F"}, + {"tab", "\t"}, + {"gt and lt", "<>"}, + {"quotes", `'"`}, + {"ASCII letters", "ASCII letters"}, + {"Unicode", "ʕ⊙ϖ⊙ʔ"}, + {"Pizza", "🍕"}, + } + const ( + prefix = `<script type="application/ld+json">` + suffix = `</script>` + templ = prefix + `"{{.}}"` + suffix + ) + tpl := Must(New("JS string is JSON string").Parse(templ)) + for _, tt := range tests { + t.Run(tt.name, func(t *testing.T) { + var buf bytes.Buffer + if err := tpl.Execute(&buf, tt.in); err != nil { + t.Fatalf("Cannot render template: %v", err) + } + trimmed := bytes.TrimSuffix(bytes.TrimPrefix(buf.Bytes(), []byte(prefix)), []byte(suffix)) + var got string + if err := json.Unmarshal(trimmed, &got); err != nil { + t.Fatalf("Cannot parse JS string %q as JSON: %v", trimmed[1:len(trimmed)-1], err) + } + if got != tt.in { + t.Errorf("Serialization changed the string value: got %q want %q", got, tt.in) + } + }) + } +} + +func TestSkipEscapeComments(t *testing.T) { + c := newTestCase(t) + tr := parse.New("root") + tr.Mode = parse.ParseComments + newT, err := tr.Parse("{{/* A comment */}}{{ 1 }}{{/* Another comment */}}", "", "", make(map[string]*parse.Tree)) + if err != nil { + t.Fatalf("Cannot parse template text: %v", err) + } + c.root, err = c.root.AddParseTree("root", newT) + if err != nil { + t.Fatalf("Cannot add parse tree to template: %v", err) + } + c.mustExecute(c.root, nil, "1") +} + +type testCase struct { + t *testing.T + root *Template +} + +func newTestCase(t *testing.T) *testCase { + return &testCase{ + t: t, + root: New("root"), + } +} + +func (c *testCase) lookup(name string) *Template { + return c.root.Lookup(name) +} + +func (c *testCase) mustParse(t *Template, text string) { + _, err := t.Parse(text) + if err != nil { + c.t.Fatalf("parse: %v", err) + } +} + +func (c *testCase) mustNotParse(t *Template, text string) { + _, err := t.Parse(text) + if err == nil { + c.t.Fatalf("parse: unexpected success") + } +} + +func (c *testCase) mustExecute(t *Template, val interface{}, want string) { + var buf bytes.Buffer + err := t.Execute(&buf, val) + if err != nil { + c.t.Fatalf("execute: %v", err) + } + if buf.String() != want { + c.t.Fatalf("template output:\n%s\nwant:\n%s", buf.String(), want) + } +} diff --git a/src/html/template/testdata/file1.tmpl b/src/html/template/testdata/file1.tmpl new file mode 100644 index 0000000..febf9d9 --- /dev/null +++ b/src/html/template/testdata/file1.tmpl @@ -0,0 +1,2 @@ +{{define "x"}}TEXT{{end}} +{{define "dotV"}}{{.V}}{{end}} diff --git a/src/html/template/testdata/file2.tmpl b/src/html/template/testdata/file2.tmpl new file mode 100644 index 0000000..39bf6fb --- /dev/null +++ b/src/html/template/testdata/file2.tmpl @@ -0,0 +1,2 @@ +{{define "dot"}}{{.}}{{end}} +{{define "nested"}}{{template "dot" .}}{{end}} diff --git a/src/html/template/testdata/fs.zip b/src/html/template/testdata/fs.zip Binary files differnew file mode 100644 index 0000000..8581313 --- /dev/null +++ b/src/html/template/testdata/fs.zip diff --git a/src/html/template/testdata/tmpl1.tmpl b/src/html/template/testdata/tmpl1.tmpl new file mode 100644 index 0000000..b72b3a3 --- /dev/null +++ b/src/html/template/testdata/tmpl1.tmpl @@ -0,0 +1,3 @@ +template1 +{{define "x"}}x{{end}} +{{template "y"}} diff --git a/src/html/template/testdata/tmpl2.tmpl b/src/html/template/testdata/tmpl2.tmpl new file mode 100644 index 0000000..16beba6 --- /dev/null +++ b/src/html/template/testdata/tmpl2.tmpl @@ -0,0 +1,3 @@ +template2 +{{define "y"}}y{{end}} +{{template "x"}} diff --git a/src/html/template/transition.go b/src/html/template/transition.go new file mode 100644 index 0000000..06df679 --- /dev/null +++ b/src/html/template/transition.go @@ -0,0 +1,592 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package template + +import ( + "bytes" + "strings" +) + +// transitionFunc is the array of context transition functions for text nodes. +// A transition function takes a context and template text input, and returns +// the updated context and the number of bytes consumed from the front of the +// input. +var transitionFunc = [...]func(context, []byte) (context, int){ + stateText: tText, + stateTag: tTag, + stateAttrName: tAttrName, + stateAfterName: tAfterName, + stateBeforeValue: tBeforeValue, + stateHTMLCmt: tHTMLCmt, + stateRCDATA: tSpecialTagEnd, + stateAttr: tAttr, + stateURL: tURL, + stateSrcset: tURL, + stateJS: tJS, + stateJSDqStr: tJSDelimited, + stateJSSqStr: tJSDelimited, + stateJSRegexp: tJSDelimited, + stateJSBlockCmt: tBlockCmt, + stateJSLineCmt: tLineCmt, + stateCSS: tCSS, + stateCSSDqStr: tCSSStr, + stateCSSSqStr: tCSSStr, + stateCSSDqURL: tCSSStr, + stateCSSSqURL: tCSSStr, + stateCSSURL: tCSSStr, + stateCSSBlockCmt: tBlockCmt, + stateCSSLineCmt: tLineCmt, + stateError: tError, +} + +var commentStart = []byte("<!--") +var commentEnd = []byte("-->") + +// tText is the context transition function for the text state. +func tText(c context, s []byte) (context, int) { + k := 0 + for { + i := k + bytes.IndexByte(s[k:], '<') + if i < k || i+1 == len(s) { + return c, len(s) + } else if i+4 <= len(s) && bytes.Equal(commentStart, s[i:i+4]) { + return context{state: stateHTMLCmt}, i + 4 + } + i++ + end := false + if s[i] == '/' { + if i+1 == len(s) { + return c, len(s) + } + end, i = true, i+1 + } + j, e := eatTagName(s, i) + if j != i { + if end { + e = elementNone + } + // We've found an HTML tag. + return context{state: stateTag, element: e}, j + } + k = j + } +} + +var elementContentType = [...]state{ + elementNone: stateText, + elementScript: stateJS, + elementStyle: stateCSS, + elementTextarea: stateRCDATA, + elementTitle: stateRCDATA, +} + +// tTag is the context transition function for the tag state. +func tTag(c context, s []byte) (context, int) { + // Find the attribute name. + i := eatWhiteSpace(s, 0) + if i == len(s) { + return c, len(s) + } + if s[i] == '>' { + return context{ + state: elementContentType[c.element], + element: c.element, + }, i + 1 + } + j, err := eatAttrName(s, i) + if err != nil { + return context{state: stateError, err: err}, len(s) + } + state, attr := stateTag, attrNone + if i == j { + return context{ + state: stateError, + err: errorf(ErrBadHTML, nil, 0, "expected space, attr name, or end of tag, but got %q", s[i:]), + }, len(s) + } + + attrName := strings.ToLower(string(s[i:j])) + if c.element == elementScript && attrName == "type" { + attr = attrScriptType + } else { + switch attrType(attrName) { + case contentTypeURL: + attr = attrURL + case contentTypeCSS: + attr = attrStyle + case contentTypeJS: + attr = attrScript + case contentTypeSrcset: + attr = attrSrcset + } + } + + if j == len(s) { + state = stateAttrName + } else { + state = stateAfterName + } + return context{state: state, element: c.element, attr: attr}, j +} + +// tAttrName is the context transition function for stateAttrName. +func tAttrName(c context, s []byte) (context, int) { + i, err := eatAttrName(s, 0) + if err != nil { + return context{state: stateError, err: err}, len(s) + } else if i != len(s) { + c.state = stateAfterName + } + return c, i +} + +// tAfterName is the context transition function for stateAfterName. +func tAfterName(c context, s []byte) (context, int) { + // Look for the start of the value. + i := eatWhiteSpace(s, 0) + if i == len(s) { + return c, len(s) + } else if s[i] != '=' { + // Occurs due to tag ending '>', and valueless attribute. + c.state = stateTag + return c, i + } + c.state = stateBeforeValue + // Consume the "=". + return c, i + 1 +} + +var attrStartStates = [...]state{ + attrNone: stateAttr, + attrScript: stateJS, + attrScriptType: stateAttr, + attrStyle: stateCSS, + attrURL: stateURL, + attrSrcset: stateSrcset, +} + +// tBeforeValue is the context transition function for stateBeforeValue. +func tBeforeValue(c context, s []byte) (context, int) { + i := eatWhiteSpace(s, 0) + if i == len(s) { + return c, len(s) + } + // Find the attribute delimiter. + delim := delimSpaceOrTagEnd + switch s[i] { + case '\'': + delim, i = delimSingleQuote, i+1 + case '"': + delim, i = delimDoubleQuote, i+1 + } + c.state, c.delim = attrStartStates[c.attr], delim + return c, i +} + +// tHTMLCmt is the context transition function for stateHTMLCmt. +func tHTMLCmt(c context, s []byte) (context, int) { + if i := bytes.Index(s, commentEnd); i != -1 { + return context{}, i + 3 + } + return c, len(s) +} + +// specialTagEndMarkers maps element types to the character sequence that +// case-insensitively signals the end of the special tag body. +var specialTagEndMarkers = [...][]byte{ + elementScript: []byte("script"), + elementStyle: []byte("style"), + elementTextarea: []byte("textarea"), + elementTitle: []byte("title"), +} + +var ( + specialTagEndPrefix = []byte("</") + tagEndSeparators = []byte("> \t\n\f/") +) + +// tSpecialTagEnd is the context transition function for raw text and RCDATA +// element states. +func tSpecialTagEnd(c context, s []byte) (context, int) { + if c.element != elementNone { + if i := indexTagEnd(s, specialTagEndMarkers[c.element]); i != -1 { + return context{}, i + } + } + return c, len(s) +} + +// indexTagEnd finds the index of a special tag end in a case insensitive way, or returns -1 +func indexTagEnd(s []byte, tag []byte) int { + res := 0 + plen := len(specialTagEndPrefix) + for len(s) > 0 { + // Try to find the tag end prefix first + i := bytes.Index(s, specialTagEndPrefix) + if i == -1 { + return i + } + s = s[i+plen:] + // Try to match the actual tag if there is still space for it + if len(tag) <= len(s) && bytes.EqualFold(tag, s[:len(tag)]) { + s = s[len(tag):] + // Check the tag is followed by a proper separator + if len(s) > 0 && bytes.IndexByte(tagEndSeparators, s[0]) != -1 { + return res + i + } + res += len(tag) + } + res += i + plen + } + return -1 +} + +// tAttr is the context transition function for the attribute state. +func tAttr(c context, s []byte) (context, int) { + return c, len(s) +} + +// tURL is the context transition function for the URL state. +func tURL(c context, s []byte) (context, int) { + if bytes.ContainsAny(s, "#?") { + c.urlPart = urlPartQueryOrFrag + } else if len(s) != eatWhiteSpace(s, 0) && c.urlPart == urlPartNone { + // HTML5 uses "Valid URL potentially surrounded by spaces" for + // attrs: https://www.w3.org/TR/html5/index.html#attributes-1 + c.urlPart = urlPartPreQuery + } + return c, len(s) +} + +// tJS is the context transition function for the JS state. +func tJS(c context, s []byte) (context, int) { + i := bytes.IndexAny(s, `"'/`) + if i == -1 { + // Entire input is non string, comment, regexp tokens. + c.jsCtx = nextJSCtx(s, c.jsCtx) + return c, len(s) + } + c.jsCtx = nextJSCtx(s[:i], c.jsCtx) + switch s[i] { + case '"': + c.state, c.jsCtx = stateJSDqStr, jsCtxRegexp + case '\'': + c.state, c.jsCtx = stateJSSqStr, jsCtxRegexp + case '/': + switch { + case i+1 < len(s) && s[i+1] == '/': + c.state, i = stateJSLineCmt, i+1 + case i+1 < len(s) && s[i+1] == '*': + c.state, i = stateJSBlockCmt, i+1 + case c.jsCtx == jsCtxRegexp: + c.state = stateJSRegexp + case c.jsCtx == jsCtxDivOp: + c.jsCtx = jsCtxRegexp + default: + return context{ + state: stateError, + err: errorf(ErrSlashAmbig, nil, 0, "'/' could start a division or regexp: %.32q", s[i:]), + }, len(s) + } + default: + panic("unreachable") + } + return c, i + 1 +} + +// tJSDelimited is the context transition function for the JS string and regexp +// states. +func tJSDelimited(c context, s []byte) (context, int) { + specials := `\"` + switch c.state { + case stateJSSqStr: + specials = `\'` + case stateJSRegexp: + specials = `\/[]` + } + + k, inCharset := 0, false + for { + i := k + bytes.IndexAny(s[k:], specials) + if i < k { + break + } + switch s[i] { + case '\\': + i++ + if i == len(s) { + return context{ + state: stateError, + err: errorf(ErrPartialEscape, nil, 0, "unfinished escape sequence in JS string: %q", s), + }, len(s) + } + case '[': + inCharset = true + case ']': + inCharset = false + default: + // end delimiter + if !inCharset { + c.state, c.jsCtx = stateJS, jsCtxDivOp + return c, i + 1 + } + } + k = i + 1 + } + + if inCharset { + // This can be fixed by making context richer if interpolation + // into charsets is desired. + return context{ + state: stateError, + err: errorf(ErrPartialCharset, nil, 0, "unfinished JS regexp charset: %q", s), + }, len(s) + } + + return c, len(s) +} + +var blockCommentEnd = []byte("*/") + +// tBlockCmt is the context transition function for /*comment*/ states. +func tBlockCmt(c context, s []byte) (context, int) { + i := bytes.Index(s, blockCommentEnd) + if i == -1 { + return c, len(s) + } + switch c.state { + case stateJSBlockCmt: + c.state = stateJS + case stateCSSBlockCmt: + c.state = stateCSS + default: + panic(c.state.String()) + } + return c, i + 2 +} + +// tLineCmt is the context transition function for //comment states. +func tLineCmt(c context, s []byte) (context, int) { + var lineTerminators string + var endState state + switch c.state { + case stateJSLineCmt: + lineTerminators, endState = "\n\r\u2028\u2029", stateJS + case stateCSSLineCmt: + lineTerminators, endState = "\n\f\r", stateCSS + // Line comments are not part of any published CSS standard but + // are supported by the 4 major browsers. + // This defines line comments as + // LINECOMMENT ::= "//" [^\n\f\d]* + // since https://www.w3.org/TR/css3-syntax/#SUBTOK-nl defines + // newlines: + // nl ::= #xA | #xD #xA | #xD | #xC + default: + panic(c.state.String()) + } + + i := bytes.IndexAny(s, lineTerminators) + if i == -1 { + return c, len(s) + } + c.state = endState + // Per section 7.4 of EcmaScript 5 : https://es5.github.com/#x7.4 + // "However, the LineTerminator at the end of the line is not + // considered to be part of the single-line comment; it is + // recognized separately by the lexical grammar and becomes part + // of the stream of input elements for the syntactic grammar." + return c, i +} + +// tCSS is the context transition function for the CSS state. +func tCSS(c context, s []byte) (context, int) { + // CSS quoted strings are almost never used except for: + // (1) URLs as in background: "/foo.png" + // (2) Multiword font-names as in font-family: "Times New Roman" + // (3) List separators in content values as in inline-lists: + // <style> + // ul.inlineList { list-style: none; padding:0 } + // ul.inlineList > li { display: inline } + // ul.inlineList > li:before { content: ", " } + // ul.inlineList > li:first-child:before { content: "" } + // </style> + // <ul class=inlineList><li>One<li>Two<li>Three</ul> + // (4) Attribute value selectors as in a[href="http://example.com/"] + // + // We conservatively treat all strings as URLs, but make some + // allowances to avoid confusion. + // + // In (1), our conservative assumption is justified. + // In (2), valid font names do not contain ':', '?', or '#', so our + // conservative assumption is fine since we will never transition past + // urlPartPreQuery. + // In (3), our protocol heuristic should not be tripped, and there + // should not be non-space content after a '?' or '#', so as long as + // we only %-encode RFC 3986 reserved characters we are ok. + // In (4), we should URL escape for URL attributes, and for others we + // have the attribute name available if our conservative assumption + // proves problematic for real code. + + k := 0 + for { + i := k + bytes.IndexAny(s[k:], `("'/`) + if i < k { + return c, len(s) + } + switch s[i] { + case '(': + // Look for url to the left. + p := bytes.TrimRight(s[:i], "\t\n\f\r ") + if endsWithCSSKeyword(p, "url") { + j := len(s) - len(bytes.TrimLeft(s[i+1:], "\t\n\f\r ")) + switch { + case j != len(s) && s[j] == '"': + c.state, j = stateCSSDqURL, j+1 + case j != len(s) && s[j] == '\'': + c.state, j = stateCSSSqURL, j+1 + default: + c.state = stateCSSURL + } + return c, j + } + case '/': + if i+1 < len(s) { + switch s[i+1] { + case '/': + c.state = stateCSSLineCmt + return c, i + 2 + case '*': + c.state = stateCSSBlockCmt + return c, i + 2 + } + } + case '"': + c.state = stateCSSDqStr + return c, i + 1 + case '\'': + c.state = stateCSSSqStr + return c, i + 1 + } + k = i + 1 + } +} + +// tCSSStr is the context transition function for the CSS string and URL states. +func tCSSStr(c context, s []byte) (context, int) { + var endAndEsc string + switch c.state { + case stateCSSDqStr, stateCSSDqURL: + endAndEsc = `\"` + case stateCSSSqStr, stateCSSSqURL: + endAndEsc = `\'` + case stateCSSURL: + // Unquoted URLs end with a newline or close parenthesis. + // The below includes the wc (whitespace character) and nl. + endAndEsc = "\\\t\n\f\r )" + default: + panic(c.state.String()) + } + + k := 0 + for { + i := k + bytes.IndexAny(s[k:], endAndEsc) + if i < k { + c, nread := tURL(c, decodeCSS(s[k:])) + return c, k + nread + } + if s[i] == '\\' { + i++ + if i == len(s) { + return context{ + state: stateError, + err: errorf(ErrPartialEscape, nil, 0, "unfinished escape sequence in CSS string: %q", s), + }, len(s) + } + } else { + c.state = stateCSS + return c, i + 1 + } + c, _ = tURL(c, decodeCSS(s[:i+1])) + k = i + 1 + } +} + +// tError is the context transition function for the error state. +func tError(c context, s []byte) (context, int) { + return c, len(s) +} + +// eatAttrName returns the largest j such that s[i:j] is an attribute name. +// It returns an error if s[i:] does not look like it begins with an +// attribute name, such as encountering a quote mark without a preceding +// equals sign. +func eatAttrName(s []byte, i int) (int, *Error) { + for j := i; j < len(s); j++ { + switch s[j] { + case ' ', '\t', '\n', '\f', '\r', '=', '>': + return j, nil + case '\'', '"', '<': + // These result in a parse warning in HTML5 and are + // indicative of serious problems if seen in an attr + // name in a template. + return -1, errorf(ErrBadHTML, nil, 0, "%q in attribute name: %.32q", s[j:j+1], s) + default: + // No-op. + } + } + return len(s), nil +} + +var elementNameMap = map[string]element{ + "script": elementScript, + "style": elementStyle, + "textarea": elementTextarea, + "title": elementTitle, +} + +// asciiAlpha reports whether c is an ASCII letter. +func asciiAlpha(c byte) bool { + return 'A' <= c && c <= 'Z' || 'a' <= c && c <= 'z' +} + +// asciiAlphaNum reports whether c is an ASCII letter or digit. +func asciiAlphaNum(c byte) bool { + return asciiAlpha(c) || '0' <= c && c <= '9' +} + +// eatTagName returns the largest j such that s[i:j] is a tag name and the tag type. +func eatTagName(s []byte, i int) (int, element) { + if i == len(s) || !asciiAlpha(s[i]) { + return i, elementNone + } + j := i + 1 + for j < len(s) { + x := s[j] + if asciiAlphaNum(x) { + j++ + continue + } + // Allow "x-y" or "x:y" but not "x-", "-y", or "x--y". + if (x == ':' || x == '-') && j+1 < len(s) && asciiAlphaNum(s[j+1]) { + j += 2 + continue + } + break + } + return j, elementNameMap[strings.ToLower(string(s[i:j]))] +} + +// eatWhiteSpace returns the largest j such that s[i:j] is white space. +func eatWhiteSpace(s []byte, i int) int { + for j := i; j < len(s); j++ { + switch s[j] { + case ' ', '\t', '\n', '\f', '\r': + // No-op. + default: + return j + } + } + return len(s) +} diff --git a/src/html/template/transition_test.go b/src/html/template/transition_test.go new file mode 100644 index 0000000..412a4c7 --- /dev/null +++ b/src/html/template/transition_test.go @@ -0,0 +1,60 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package template + +import ( + "bytes" + "strings" + "testing" +) + +func TestFindEndTag(t *testing.T) { + tests := []struct { + s, tag string + want int + }{ + {"", "tag", -1}, + {"hello </textarea> hello", "textarea", 6}, + {"hello </TEXTarea> hello", "textarea", 6}, + {"hello </textAREA>", "textarea", 6}, + {"hello </textarea", "textareax", -1}, + {"hello </textarea>", "tag", -1}, + {"hello tag </textarea", "tag", -1}, + {"hello </tag> </other> </textarea> <other>", "textarea", 22}, + {"</textarea> <other>", "textarea", 0}, + {"<div> </div> </TEXTAREA>", "textarea", 13}, + {"<div> </div> </TEXTAREA\t>", "textarea", 13}, + {"<div> </div> </TEXTAREA >", "textarea", 13}, + {"<div> </div> </TEXTAREAfoo", "textarea", -1}, + {"</TEXTAREAfoo </textarea>", "textarea", 14}, + {"<</script >", "script", 1}, + {"</script>", "textarea", -1}, + } + for _, test := range tests { + if got := indexTagEnd([]byte(test.s), []byte(test.tag)); test.want != got { + t.Errorf("%q/%q: want\n\t%d\nbut got\n\t%d", test.s, test.tag, test.want, got) + } + } +} + +func BenchmarkTemplateSpecialTags(b *testing.B) { + + r := struct { + Name, Gift string + }{"Aunt Mildred", "bone china tea set"} + + h1 := "<textarea> Hello Hello Hello </textarea> " + h2 := "<textarea> <p> Dear {{.Name}},\n{{with .Gift}}Thank you for the lovely {{.}}. {{end}}\nBest wishes. </p>\n</textarea>" + html := strings.Repeat(h1, 100) + h2 + strings.Repeat(h1, 100) + h2 + + var buf bytes.Buffer + for i := 0; i < b.N; i++ { + tmpl := Must(New("foo").Parse(html)) + if err := tmpl.Execute(&buf, r); err != nil { + b.Fatal(err) + } + buf.Reset() + } +} diff --git a/src/html/template/url.go b/src/html/template/url.go new file mode 100644 index 0000000..6f8185a --- /dev/null +++ b/src/html/template/url.go @@ -0,0 +1,219 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package template + +import ( + "bytes" + "fmt" + "strings" +) + +// urlFilter returns its input unless it contains an unsafe scheme in which +// case it defangs the entire URL. +// +// Schemes that cause unintended side effects that are irreversible without user +// interaction are considered unsafe. For example, clicking on a "javascript:" +// link can immediately trigger JavaScript code execution. +// +// This filter conservatively assumes that all schemes other than the following +// are unsafe: +// * http: Navigates to a new website, and may open a new window or tab. +// These side effects can be reversed by navigating back to the +// previous website, or closing the window or tab. No irreversible +// changes will take place without further user interaction with +// the new website. +// * https: Same as http. +// * mailto: Opens an email program and starts a new draft. This side effect +// is not irreversible until the user explicitly clicks send; it +// can be undone by closing the email program. +// +// To allow URLs containing other schemes to bypass this filter, developers must +// explicitly indicate that such a URL is expected and safe by encapsulating it +// in a template.URL value. +func urlFilter(args ...interface{}) string { + s, t := stringify(args...) + if t == contentTypeURL { + return s + } + if !isSafeURL(s) { + return "#" + filterFailsafe + } + return s +} + +// isSafeURL is true if s is a relative URL or if URL has a protocol in +// (http, https, mailto). +func isSafeURL(s string) bool { + if i := strings.IndexRune(s, ':'); i >= 0 && !strings.ContainsRune(s[:i], '/') { + + protocol := s[:i] + if !strings.EqualFold(protocol, "http") && !strings.EqualFold(protocol, "https") && !strings.EqualFold(protocol, "mailto") { + return false + } + } + return true +} + +// urlEscaper produces an output that can be embedded in a URL query. +// The output can be embedded in an HTML attribute without further escaping. +func urlEscaper(args ...interface{}) string { + return urlProcessor(false, args...) +} + +// urlNormalizer normalizes URL content so it can be embedded in a quote-delimited +// string or parenthesis delimited url(...). +// The normalizer does not encode all HTML specials. Specifically, it does not +// encode '&' so correct embedding in an HTML attribute requires escaping of +// '&' to '&'. +func urlNormalizer(args ...interface{}) string { + return urlProcessor(true, args...) +} + +// urlProcessor normalizes (when norm is true) or escapes its input to produce +// a valid hierarchical or opaque URL part. +func urlProcessor(norm bool, args ...interface{}) string { + s, t := stringify(args...) + if t == contentTypeURL { + norm = true + } + var b bytes.Buffer + if processURLOnto(s, norm, &b) { + return b.String() + } + return s +} + +// processURLOnto appends a normalized URL corresponding to its input to b +// and reports whether the appended content differs from s. +func processURLOnto(s string, norm bool, b *bytes.Buffer) bool { + b.Grow(len(s) + 16) + written := 0 + // The byte loop below assumes that all URLs use UTF-8 as the + // content-encoding. This is similar to the URI to IRI encoding scheme + // defined in section 3.1 of RFC 3987, and behaves the same as the + // EcmaScript builtin encodeURIComponent. + // It should not cause any misencoding of URLs in pages with + // Content-type: text/html;charset=UTF-8. + for i, n := 0, len(s); i < n; i++ { + c := s[i] + switch c { + // Single quote and parens are sub-delims in RFC 3986, but we + // escape them so the output can be embedded in single + // quoted attributes and unquoted CSS url(...) constructs. + // Single quotes are reserved in URLs, but are only used in + // the obsolete "mark" rule in an appendix in RFC 3986 + // so can be safely encoded. + case '!', '#', '$', '&', '*', '+', ',', '/', ':', ';', '=', '?', '@', '[', ']': + if norm { + continue + } + // Unreserved according to RFC 3986 sec 2.3 + // "For consistency, percent-encoded octets in the ranges of + // ALPHA (%41-%5A and %61-%7A), DIGIT (%30-%39), hyphen (%2D), + // period (%2E), underscore (%5F), or tilde (%7E) should not be + // created by URI producers + case '-', '.', '_', '~': + continue + case '%': + // When normalizing do not re-encode valid escapes. + if norm && i+2 < len(s) && isHex(s[i+1]) && isHex(s[i+2]) { + continue + } + default: + // Unreserved according to RFC 3986 sec 2.3 + if 'a' <= c && c <= 'z' { + continue + } + if 'A' <= c && c <= 'Z' { + continue + } + if '0' <= c && c <= '9' { + continue + } + } + b.WriteString(s[written:i]) + fmt.Fprintf(b, "%%%02x", c) + written = i + 1 + } + b.WriteString(s[written:]) + return written != 0 +} + +// Filters and normalizes srcset values which are comma separated +// URLs followed by metadata. +func srcsetFilterAndEscaper(args ...interface{}) string { + s, t := stringify(args...) + switch t { + case contentTypeSrcset: + return s + case contentTypeURL: + // Normalizing gets rid of all HTML whitespace + // which separate the image URL from its metadata. + var b bytes.Buffer + if processURLOnto(s, true, &b) { + s = b.String() + } + // Additionally, commas separate one source from another. + return strings.ReplaceAll(s, ",", "%2c") + } + + var b bytes.Buffer + written := 0 + for i := 0; i < len(s); i++ { + if s[i] == ',' { + filterSrcsetElement(s, written, i, &b) + b.WriteString(",") + written = i + 1 + } + } + filterSrcsetElement(s, written, len(s), &b) + return b.String() +} + +// Derived from https://play.golang.org/p/Dhmj7FORT5 +const htmlSpaceAndASCIIAlnumBytes = "\x00\x36\x00\x00\x01\x00\xff\x03\xfe\xff\xff\x07\xfe\xff\xff\x07" + +// isHTMLSpace is true iff c is a whitespace character per +// https://infra.spec.whatwg.org/#ascii-whitespace +func isHTMLSpace(c byte) bool { + return (c <= 0x20) && 0 != (htmlSpaceAndASCIIAlnumBytes[c>>3]&(1<<uint(c&0x7))) +} + +func isHTMLSpaceOrASCIIAlnum(c byte) bool { + return (c < 0x80) && 0 != (htmlSpaceAndASCIIAlnumBytes[c>>3]&(1<<uint(c&0x7))) +} + +func filterSrcsetElement(s string, left int, right int, b *bytes.Buffer) { + start := left + for start < right && isHTMLSpace(s[start]) { + start++ + } + end := right + for i := start; i < right; i++ { + if isHTMLSpace(s[i]) { + end = i + break + } + } + if url := s[start:end]; isSafeURL(url) { + // If image metadata is only spaces or alnums then + // we don't need to URL normalize it. + metadataOk := true + for i := end; i < right; i++ { + if !isHTMLSpaceOrASCIIAlnum(s[i]) { + metadataOk = false + break + } + } + if metadataOk { + b.WriteString(s[left:start]) + processURLOnto(url, true, b) + b.WriteString(s[end:right]) + return + } + } + b.WriteString("#") + b.WriteString(filterFailsafe) +} diff --git a/src/html/template/url_test.go b/src/html/template/url_test.go new file mode 100644 index 0000000..75c354e --- /dev/null +++ b/src/html/template/url_test.go @@ -0,0 +1,169 @@ +// Copyright 2011 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +package template + +import ( + "testing" +) + +func TestURLNormalizer(t *testing.T) { + tests := []struct { + url, want string + }{ + {"", ""}, + { + "http://example.com:80/foo/bar?q=foo%20&bar=x+y#frag", + "http://example.com:80/foo/bar?q=foo%20&bar=x+y#frag", + }, + {" ", "%20"}, + {"%7c", "%7c"}, + {"%7C", "%7C"}, + {"%2", "%252"}, + {"%", "%25"}, + {"%z", "%25z"}, + {"/foo|bar/%5c\u1234", "/foo%7cbar/%5c%e1%88%b4"}, + } + for _, test := range tests { + if got := urlNormalizer(test.url); test.want != got { + t.Errorf("%q: want\n\t%q\nbut got\n\t%q", test.url, test.want, got) + } + if test.want != urlNormalizer(test.want) { + t.Errorf("not idempotent: %q", test.want) + } + } +} + +func TestURLFilters(t *testing.T) { + input := ("\x00\x01\x02\x03\x04\x05\x06\x07\x08\t\n\x0b\x0c\r\x0e\x0f" + + "\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f" + + ` !"#$%&'()*+,-./` + + `0123456789:;<=>?` + + `@ABCDEFGHIJKLMNO` + + `PQRSTUVWXYZ[\]^_` + + "`abcdefghijklmno" + + "pqrstuvwxyz{|}~\x7f" + + "\u00A0\u0100\u2028\u2029\ufeff\U0001D11E") + + tests := []struct { + name string + escaper func(...interface{}) string + escaped string + }{ + { + "urlEscaper", + urlEscaper, + "%00%01%02%03%04%05%06%07%08%09%0a%0b%0c%0d%0e%0f" + + "%10%11%12%13%14%15%16%17%18%19%1a%1b%1c%1d%1e%1f" + + "%20%21%22%23%24%25%26%27%28%29%2a%2b%2c-.%2f" + + "0123456789%3a%3b%3c%3d%3e%3f" + + "%40ABCDEFGHIJKLMNO" + + "PQRSTUVWXYZ%5b%5c%5d%5e_" + + "%60abcdefghijklmno" + + "pqrstuvwxyz%7b%7c%7d~%7f" + + "%c2%a0%c4%80%e2%80%a8%e2%80%a9%ef%bb%bf%f0%9d%84%9e", + }, + { + "urlNormalizer", + urlNormalizer, + "%00%01%02%03%04%05%06%07%08%09%0a%0b%0c%0d%0e%0f" + + "%10%11%12%13%14%15%16%17%18%19%1a%1b%1c%1d%1e%1f" + + "%20!%22#$%25&%27%28%29*+,-./" + + "0123456789:;%3c=%3e?" + + "@ABCDEFGHIJKLMNO" + + "PQRSTUVWXYZ[%5c]%5e_" + + "%60abcdefghijklmno" + + "pqrstuvwxyz%7b%7c%7d~%7f" + + "%c2%a0%c4%80%e2%80%a8%e2%80%a9%ef%bb%bf%f0%9d%84%9e", + }, + } + + for _, test := range tests { + if s := test.escaper(input); s != test.escaped { + t.Errorf("%s: want\n\t%q\ngot\n\t%q", test.name, test.escaped, s) + continue + } + } +} + +func TestSrcsetFilter(t *testing.T) { + tests := []struct { + name string + input string + want string + }{ + { + "one ok", + "http://example.com/img.png", + "http://example.com/img.png", + }, + { + "one ok with metadata", + " /img.png 200w", + " /img.png 200w", + }, + { + "one bad", + "javascript:alert(1) 200w", + "#ZgotmplZ", + }, + { + "two ok", + "foo.png, bar.png", + "foo.png, bar.png", + }, + { + "left bad", + "javascript:alert(1), /foo.png", + "#ZgotmplZ, /foo.png", + }, + { + "right bad", + "/bogus#, javascript:alert(1)", + "/bogus#,#ZgotmplZ", + }, + } + + for _, test := range tests { + if got := srcsetFilterAndEscaper(test.input); got != test.want { + t.Errorf("%s: srcsetFilterAndEscaper(%q) want %q != %q", test.name, test.input, test.want, got) + } + } +} + +func BenchmarkURLEscaper(b *testing.B) { + for i := 0; i < b.N; i++ { + urlEscaper("http://example.com:80/foo?q=bar%20&baz=x+y#frag") + } +} + +func BenchmarkURLEscaperNoSpecials(b *testing.B) { + for i := 0; i < b.N; i++ { + urlEscaper("TheQuickBrownFoxJumpsOverTheLazyDog.") + } +} + +func BenchmarkURLNormalizer(b *testing.B) { + for i := 0; i < b.N; i++ { + urlNormalizer("The quick brown fox jumps over the lazy dog.\n") + } +} + +func BenchmarkURLNormalizerNoSpecials(b *testing.B) { + for i := 0; i < b.N; i++ { + urlNormalizer("http://example.com:80/foo?q=bar%20&baz=x+y#frag") + } +} + +func BenchmarkSrcsetFilter(b *testing.B) { + for i := 0; i < b.N; i++ { + srcsetFilterAndEscaper(" /foo/bar.png 200w, /baz/boo(1).png") + } +} + +func BenchmarkSrcsetFilterNoSpecials(b *testing.B) { + for i := 0; i < b.N; i++ { + srcsetFilterAndEscaper("http://example.com:80/foo?q=bar%20&baz=x+y#frag") + } +} diff --git a/src/html/template/urlpart_string.go b/src/html/template/urlpart_string.go new file mode 100644 index 0000000..813eea9 --- /dev/null +++ b/src/html/template/urlpart_string.go @@ -0,0 +1,16 @@ +// Code generated by "stringer -type urlPart"; DO NOT EDIT. + +package template + +import "strconv" + +const _urlPart_name = "urlPartNoneurlPartPreQueryurlPartQueryOrFragurlPartUnknown" + +var _urlPart_index = [...]uint8{0, 11, 26, 44, 58} + +func (i urlPart) String() string { + if i >= urlPart(len(_urlPart_index)-1) { + return "urlPart(" + strconv.FormatInt(int64(i), 10) + ")" + } + return _urlPart_name[_urlPart_index[i]:_urlPart_index[i+1]] +} |