Adding upstream version 1.21.8.upstream/1.21.8

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

2 files changed, 217 insertions, 0 deletions

diff --git a/src/cmd/internal/quoted/quoted.go b/src/cmd/internal/quoted/quoted.go
new file mode 100644
index 0000000..a812275
--- /dev/null
+++ b/src/cmd/internal/quoted/quoted.go
@@ -0,0 +1,129 @@
+// Copyright 2017 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 quoted provides string manipulation utilities.
+package quoted
+
+import (
+	"flag"
+	"fmt"
+	"strings"
+	"unicode"
+)
+
+func isSpaceByte(c byte) bool {
+	return c == ' ' || c == '\t' || c == '\n' || c == '\r'
+}
+
+// Split splits s into a list of fields,
+// allowing single or double quotes around elements.
+// There is no unescaping or other processing within
+// quoted fields.
+//
+// Keep in sync with cmd/dist/quoted.go
+func Split(s string) ([]string, error) {
+	// Split fields allowing '' or "" around elements.
+	// Quotes further inside the string do not count.
+	var f []string
+	for len(s) > 0 {
+		for len(s) > 0 && isSpaceByte(s[0]) {
+			s = s[1:]
+		}
+		if len(s) == 0 {
+			break
+		}
+		// Accepted quoted string. No unescaping inside.
+		if s[0] == '"' || s[0] == '\'' {
+			quote := s[0]
+			s = s[1:]
+			i := 0
+			for i < len(s) && s[i] != quote {
+				i++
+			}
+			if i >= len(s) {
+				return nil, fmt.Errorf("unterminated %c string", quote)
+			}
+			f = append(f, s[:i])
+			s = s[i+1:]
+			continue
+		}
+		i := 0
+		for i < len(s) && !isSpaceByte(s[i]) {
+			i++
+		}
+		f = append(f, s[:i])
+		s = s[i:]
+	}
+	return f, nil
+}
+
+// Join joins a list of arguments into a string that can be parsed
+// with Split. Arguments are quoted only if necessary; arguments
+// without spaces or quotes are kept as-is. No argument may contain both
+// single and double quotes.
+func Join(args []string) (string, error) {
+	var buf []byte
+	for i, arg := range args {
+		if i > 0 {
+			buf = append(buf, ' ')
+		}
+		var sawSpace, sawSingleQuote, sawDoubleQuote bool
+		for _, c := range arg {
+			switch {
+			case c > unicode.MaxASCII:
+				continue
+			case isSpaceByte(byte(c)):
+				sawSpace = true
+			case c == '\'':
+				sawSingleQuote = true
+			case c == '"':
+				sawDoubleQuote = true
+			}
+		}
+		switch {
+		case !sawSpace && !sawSingleQuote && !sawDoubleQuote:
+			buf = append(buf, arg...)
+
+		case !sawSingleQuote:
+			buf = append(buf, '\'')
+			buf = append(buf, arg...)
+			buf = append(buf, '\'')
+
+		case !sawDoubleQuote:
+			buf = append(buf, '"')
+			buf = append(buf, arg...)
+			buf = append(buf, '"')
+
+		default:
+			return "", fmt.Errorf("argument %q contains both single and double quotes and cannot be quoted", arg)
+		}
+	}
+	return string(buf), nil
+}
+
+// A Flag parses a list of string arguments encoded with Join.
+// It is useful for flags like cmd/link's -extldflags.
+type Flag []string
+
+var _ flag.Value = (*Flag)(nil)
+
+func (f *Flag) Set(v string) error {
+	fs, err := Split(v)
+	if err != nil {
+		return err
+	}
+	*f = fs[:len(fs):len(fs)]
+	return nil
+}
+
+func (f *Flag) String() string {
+	if f == nil {
+		return ""
+	}
+	s, err := Join(*f)
+	if err != nil {
+		return strings.Join(*f, " ")
+	}
+	return s
+}
diff --git a/src/cmd/internal/quoted/quoted_test.go b/src/cmd/internal/quoted/quoted_test.go
new file mode 100644
index 0000000..d76270c
--- /dev/null
+++ b/src/cmd/internal/quoted/quoted_test.go
@@ -0,0 +1,88 @@
+// Copyright 2020 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 quoted
+
+import (
+	"reflect"
+	"strings"
+	"testing"
+)
+
+func TestSplit(t *testing.T) {
+	for _, test := range []struct {
+		name    string
+		value   string
+		want    []string
+		wantErr string
+	}{
+		{name: "empty", value: "", want: nil},
+		{name: "space", value: " ", want: nil},
+		{name: "one", value: "a", want: []string{"a"}},
+		{name: "leading_space", value: " a", want: []string{"a"}},
+		{name: "trailing_space", value: "a ", want: []string{"a"}},
+		{name: "two", value: "a b", want: []string{"a", "b"}},
+		{name: "two_multi_space", value: "a  b", want: []string{"a", "b"}},
+		{name: "two_tab", value: "a\tb", want: []string{"a", "b"}},
+		{name: "two_newline", value: "a\nb", want: []string{"a", "b"}},
+		{name: "quote_single", value: `'a b'`, want: []string{"a b"}},
+		{name: "quote_double", value: `"a b"`, want: []string{"a b"}},
+		{name: "quote_both", value: `'a '"b "`, want: []string{"a ", "b "}},
+		{name: "quote_contains", value: `'a "'"'b"`, want: []string{`a "`, `'b`}},
+		{name: "escape", value: `\'`, want: []string{`\'`}},
+		{name: "quote_unclosed", value: `'a`, wantErr: "unterminated ' string"},
+	} {
+		t.Run(test.name, func(t *testing.T) {
+			got, err := Split(test.value)
+			if err != nil {
+				if test.wantErr == "" {
+					t.Fatalf("unexpected error: %v", err)
+				} else if errMsg := err.Error(); !strings.Contains(errMsg, test.wantErr) {
+					t.Fatalf("error %q does not contain %q", errMsg, test.wantErr)
+				}
+				return
+			}
+			if test.wantErr != "" {
+				t.Fatalf("unexpected success; wanted error containing %q", test.wantErr)
+			}
+			if !reflect.DeepEqual(got, test.want) {
+				t.Errorf("got %q; want %q", got, test.want)
+			}
+		})
+	}
+}
+
+func TestJoin(t *testing.T) {
+	for _, test := range []struct {
+		name          string
+		args          []string
+		want, wantErr string
+	}{
+		{name: "empty", args: nil, want: ""},
+		{name: "one", args: []string{"a"}, want: "a"},
+		{name: "two", args: []string{"a", "b"}, want: "a b"},
+		{name: "space", args: []string{"a ", "b"}, want: "'a ' b"},
+		{name: "newline", args: []string{"a\n", "b"}, want: "'a\n' b"},
+		{name: "quote", args: []string{`'a `, "b"}, want: `"'a " b`},
+		{name: "unquoteable", args: []string{`'"`}, wantErr: "contains both single and double quotes and cannot be quoted"},
+	} {
+		t.Run(test.name, func(t *testing.T) {
+			got, err := Join(test.args)
+			if err != nil {
+				if test.wantErr == "" {
+					t.Fatalf("unexpected error: %v", err)
+				} else if errMsg := err.Error(); !strings.Contains(errMsg, test.wantErr) {
+					t.Fatalf("error %q does not contain %q", errMsg, test.wantErr)
+				}
+				return
+			}
+			if test.wantErr != "" {
+				t.Fatalf("unexpected success; wanted error containing %q", test.wantErr)
+			}
+			if got != test.want {
+				t.Errorf("got %s; want %s", got, test.want)
+			}
+		})
+	}
+}