Adding upstream version 1.16.10.upstream/1.16.10upstream

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

5 files changed, 536 insertions, 0 deletions

diff --git a/src/go/internal/srcimporter/srcimporter.go b/src/go/internal/srcimporter/srcimporter.go
new file mode 100644
index 0000000..438ae0f
--- /dev/null
+++ b/src/go/internal/srcimporter/srcimporter.go
@@ -0,0 +1,265 @@
+// 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 srcimporter implements importing directly
+// from source files rather than installed packages.
+package srcimporter // import "go/internal/srcimporter"
+
+import (
+	"fmt"
+	"go/ast"
+	"go/build"
+	"go/parser"
+	"go/token"
+	"go/types"
+	exec "internal/execabs"
+	"io"
+	"os"
+	"path/filepath"
+	"strings"
+	"sync"
+	_ "unsafe" // for go:linkname
+)
+
+// An Importer provides the context for importing packages from source code.
+type Importer struct {
+	ctxt     *build.Context
+	fset     *token.FileSet
+	sizes    types.Sizes
+	packages map[string]*types.Package
+}
+
+// NewImporter returns a new Importer for the given context, file set, and map
+// of packages. The context is used to resolve import paths to package paths,
+// and identifying the files belonging to the package. If the context provides
+// non-nil file system functions, they are used instead of the regular package
+// os functions. The file set is used to track position information of package
+// files; and imported packages are added to the packages map.
+func New(ctxt *build.Context, fset *token.FileSet, packages map[string]*types.Package) *Importer {
+	return &Importer{
+		ctxt:     ctxt,
+		fset:     fset,
+		sizes:    types.SizesFor(ctxt.Compiler, ctxt.GOARCH), // uses go/types default if GOARCH not found
+		packages: packages,
+	}
+}
+
+// Importing is a sentinel taking the place in Importer.packages
+// for a package that is in the process of being imported.
+var importing types.Package
+
+// Import(path) is a shortcut for ImportFrom(path, ".", 0).
+func (p *Importer) Import(path string) (*types.Package, error) {
+	return p.ImportFrom(path, ".", 0) // use "." rather than "" (see issue #24441)
+}
+
+// ImportFrom imports the package with the given import path resolved from the given srcDir,
+// adds the new package to the set of packages maintained by the importer, and returns the
+// package. Package path resolution and file system operations are controlled by the context
+// maintained with the importer. The import mode must be zero but is otherwise ignored.
+// Packages that are not comprised entirely of pure Go files may fail to import because the
+// type checker may not be able to determine all exported entities (e.g. due to cgo dependencies).
+func (p *Importer) ImportFrom(path, srcDir string, mode types.ImportMode) (*types.Package, error) {
+	if mode != 0 {
+		panic("non-zero import mode")
+	}
+
+	if abs, err := p.absPath(srcDir); err == nil { // see issue #14282
+		srcDir = abs
+	}
+	bp, err := p.ctxt.Import(path, srcDir, 0)
+	if err != nil {
+		return nil, err // err may be *build.NoGoError - return as is
+	}
+
+	// package unsafe is known to the type checker
+	if bp.ImportPath == "unsafe" {
+		return types.Unsafe, nil
+	}
+
+	// no need to re-import if the package was imported completely before
+	pkg := p.packages[bp.ImportPath]
+	if pkg != nil {
+		if pkg == &importing {
+			return nil, fmt.Errorf("import cycle through package %q", bp.ImportPath)
+		}
+		if !pkg.Complete() {
+			// Package exists but is not complete - we cannot handle this
+			// at the moment since the source importer replaces the package
+			// wholesale rather than augmenting it (see #19337 for details).
+			// Return incomplete package with error (see #16088).
+			return pkg, fmt.Errorf("reimported partially imported package %q", bp.ImportPath)
+		}
+		return pkg, nil
+	}
+
+	p.packages[bp.ImportPath] = &importing
+	defer func() {
+		// clean up in case of error
+		// TODO(gri) Eventually we may want to leave a (possibly empty)
+		// package in the map in all cases (and use that package to
+		// identify cycles). See also issue 16088.
+		if p.packages[bp.ImportPath] == &importing {
+			p.packages[bp.ImportPath] = nil
+		}
+	}()
+
+	var filenames []string
+	filenames = append(filenames, bp.GoFiles...)
+	filenames = append(filenames, bp.CgoFiles...)
+
+	files, err := p.parseFiles(bp.Dir, filenames)
+	if err != nil {
+		return nil, err
+	}
+
+	// type-check package files
+	var firstHardErr error
+	conf := types.Config{
+		IgnoreFuncBodies: true,
+		// continue type-checking after the first error
+		Error: func(err error) {
+			if firstHardErr == nil && !err.(types.Error).Soft {
+				firstHardErr = err
+			}
+		},
+		Importer: p,
+		Sizes:    p.sizes,
+	}
+	if len(bp.CgoFiles) > 0 {
+		if p.ctxt.OpenFile != nil {
+			// cgo, gcc, pkg-config, etc. do not support
+			// build.Context's VFS.
+			conf.FakeImportC = true
+		} else {
+			setUsesCgo(&conf)
+			file, err := p.cgo(bp)
+			if err != nil {
+				return nil, err
+			}
+			files = append(files, file)
+		}
+	}
+
+	pkg, err = conf.Check(bp.ImportPath, p.fset, files, nil)
+	if err != nil {
+		// If there was a hard error it is possibly unsafe
+		// to use the package as it may not be fully populated.
+		// Do not return it (see also #20837, #20855).
+		if firstHardErr != nil {
+			pkg = nil
+			err = firstHardErr // give preference to first hard error over any soft error
+		}
+		return pkg, fmt.Errorf("type-checking package %q failed (%v)", bp.ImportPath, err)
+	}
+	if firstHardErr != nil {
+		// this can only happen if we have a bug in go/types
+		panic("package is not safe yet no error was returned")
+	}
+
+	p.packages[bp.ImportPath] = pkg
+	return pkg, nil
+}
+
+func (p *Importer) parseFiles(dir string, filenames []string) ([]*ast.File, error) {
+	// use build.Context's OpenFile if there is one
+	open := p.ctxt.OpenFile
+	if open == nil {
+		open = func(name string) (io.ReadCloser, error) { return os.Open(name) }
+	}
+
+	files := make([]*ast.File, len(filenames))
+	errors := make([]error, len(filenames))
+
+	var wg sync.WaitGroup
+	wg.Add(len(filenames))
+	for i, filename := range filenames {
+		go func(i int, filepath string) {
+			defer wg.Done()
+			src, err := open(filepath)
+			if err != nil {
+				errors[i] = err // open provides operation and filename in error
+				return
+			}
+			files[i], errors[i] = parser.ParseFile(p.fset, filepath, src, 0)
+			src.Close() // ignore Close error - parsing may have succeeded which is all we need
+		}(i, p.joinPath(dir, filename))
+	}
+	wg.Wait()
+
+	// if there are errors, return the first one for deterministic results
+	for _, err := range errors {
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	return files, nil
+}
+
+func (p *Importer) cgo(bp *build.Package) (*ast.File, error) {
+	tmpdir, err := os.MkdirTemp("", "srcimporter")
+	if err != nil {
+		return nil, err
+	}
+	defer os.RemoveAll(tmpdir)
+
+	args := []string{"go", "tool", "cgo", "-objdir", tmpdir}
+	if bp.Goroot {
+		switch bp.ImportPath {
+		case "runtime/cgo":
+			args = append(args, "-import_runtime_cgo=false", "-import_syscall=false")
+		case "runtime/race":
+			args = append(args, "-import_syscall=false")
+		}
+	}
+	args = append(args, "--")
+	args = append(args, strings.Fields(os.Getenv("CGO_CPPFLAGS"))...)
+	args = append(args, bp.CgoCPPFLAGS...)
+	if len(bp.CgoPkgConfig) > 0 {
+		cmd := exec.Command("pkg-config", append([]string{"--cflags"}, bp.CgoPkgConfig...)...)
+		out, err := cmd.CombinedOutput()
+		if err != nil {
+			return nil, err
+		}
+		args = append(args, strings.Fields(string(out))...)
+	}
+	args = append(args, "-I", tmpdir)
+	args = append(args, strings.Fields(os.Getenv("CGO_CFLAGS"))...)
+	args = append(args, bp.CgoCFLAGS...)
+	args = append(args, bp.CgoFiles...)
+
+	cmd := exec.Command(args[0], args[1:]...)
+	cmd.Dir = bp.Dir
+	if err := cmd.Run(); err != nil {
+		return nil, err
+	}
+
+	return parser.ParseFile(p.fset, filepath.Join(tmpdir, "_cgo_gotypes.go"), nil, 0)
+}
+
+// context-controlled file system operations
+
+func (p *Importer) absPath(path string) (string, error) {
+	// TODO(gri) This should be using p.ctxt.AbsPath which doesn't
+	// exist but probably should. See also issue #14282.
+	return filepath.Abs(path)
+}
+
+func (p *Importer) isAbsPath(path string) bool {
+	if f := p.ctxt.IsAbsPath; f != nil {
+		return f(path)
+	}
+	return filepath.IsAbs(path)
+}
+
+func (p *Importer) joinPath(elem ...string) string {
+	if f := p.ctxt.JoinPath; f != nil {
+		return f(elem...)
+	}
+	return filepath.Join(elem...)
+}
+
+//go:linkname setUsesCgo go/types.srcimporter_setUsesCgo
+func setUsesCgo(conf *types.Config)
diff --git a/src/go/internal/srcimporter/srcimporter_test.go b/src/go/internal/srcimporter/srcimporter_test.go
new file mode 100644
index 0000000..05b12f1
--- /dev/null
+++ b/src/go/internal/srcimporter/srcimporter_test.go
@@ -0,0 +1,254 @@
+// 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 srcimporter
+
+import (
+	"flag"
+	"go/build"
+	"go/token"
+	"go/types"
+	"internal/testenv"
+	"os"
+	"path"
+	"path/filepath"
+	"runtime"
+	"strings"
+	"testing"
+	"time"
+)
+
+func TestMain(m *testing.M) {
+	flag.Parse()
+	if goTool, err := testenv.GoTool(); err == nil {
+		os.Setenv("PATH", filepath.Dir(goTool)+string(os.PathListSeparator)+os.Getenv("PATH"))
+	}
+	os.Exit(m.Run())
+}
+
+const maxTime = 2 * time.Second
+
+var importer = New(&build.Default, token.NewFileSet(), make(map[string]*types.Package))
+
+func doImport(t *testing.T, path, srcDir string) {
+	t0 := time.Now()
+	if _, err := importer.ImportFrom(path, srcDir, 0); err != nil {
+		// don't report an error if there's no buildable Go files
+		if _, nogo := err.(*build.NoGoError); !nogo {
+			t.Errorf("import %q failed (%v)", path, err)
+		}
+		return
+	}
+	t.Logf("import %q: %v", path, time.Since(t0))
+}
+
+// walkDir imports the all the packages with the given path
+// prefix recursively. It returns the number of packages
+// imported and whether importing was aborted because time
+// has passed endTime.
+func walkDir(t *testing.T, path string, endTime time.Time) (int, bool) {
+	if time.Now().After(endTime) {
+		t.Log("testing time used up")
+		return 0, true
+	}
+
+	// ignore fake packages and testdata directories
+	if path == "builtin" || path == "unsafe" || strings.HasSuffix(path, "testdata") {
+		return 0, false
+	}
+
+	list, err := os.ReadDir(filepath.Join(runtime.GOROOT(), "src", path))
+	if err != nil {
+		t.Fatalf("walkDir %s failed (%v)", path, err)
+	}
+
+	nimports := 0
+	hasGoFiles := false
+	for _, f := range list {
+		if f.IsDir() {
+			n, abort := walkDir(t, filepath.Join(path, f.Name()), endTime)
+			nimports += n
+			if abort {
+				return nimports, true
+			}
+		} else if strings.HasSuffix(f.Name(), ".go") {
+			hasGoFiles = true
+		}
+	}
+
+	if hasGoFiles {
+		doImport(t, path, "")
+		nimports++
+	}
+
+	return nimports, false
+}
+
+func TestImportStdLib(t *testing.T) {
+	if !testenv.HasSrc() {
+		t.Skip("no source code available")
+	}
+
+	if testing.Short() && testenv.Builder() == "" {
+		t.Skip("skipping in -short mode")
+	}
+	dt := maxTime
+	nimports, _ := walkDir(t, "", time.Now().Add(dt)) // installed packages
+	t.Logf("tested %d imports", nimports)
+}
+
+var importedObjectTests = []struct {
+	name string
+	want string
+}{
+	{"flag.Bool", "func Bool(name string, value bool, usage string) *bool"},
+	{"io.Reader", "type Reader interface{Read(p []byte) (n int, err error)}"},
+	{"io.ReadWriter", "type ReadWriter interface{Reader; Writer}"}, // go/types.gcCompatibilityMode is off => interface not flattened
+	{"math.Pi", "const Pi untyped float"},
+	{"math.Sin", "func Sin(x float64) float64"},
+	{"math/big.Int", "type Int struct{neg bool; abs nat}"},
+	{"golang.org/x/text/unicode/norm.MaxSegmentSize", "const MaxSegmentSize untyped int"},
+}
+
+func TestImportedTypes(t *testing.T) {
+	if !testenv.HasSrc() {
+		t.Skip("no source code available")
+	}
+
+	for _, test := range importedObjectTests {
+		i := strings.LastIndex(test.name, ".")
+		if i < 0 {
+			t.Fatal("invalid test data format")
+		}
+		importPath := test.name[:i]
+		objName := test.name[i+1:]
+
+		pkg, err := importer.ImportFrom(importPath, ".", 0)
+		if err != nil {
+			t.Error(err)
+			continue
+		}
+
+		obj := pkg.Scope().Lookup(objName)
+		if obj == nil {
+			t.Errorf("%s: object not found", test.name)
+			continue
+		}
+
+		got := types.ObjectString(obj, types.RelativeTo(pkg))
+		if got != test.want {
+			t.Errorf("%s: got %q; want %q", test.name, got, test.want)
+		}
+
+		if named, _ := obj.Type().(*types.Named); named != nil {
+			verifyInterfaceMethodRecvs(t, named, 0)
+		}
+	}
+}
+
+// verifyInterfaceMethodRecvs verifies that method receiver types
+// are named if the methods belong to a named interface type.
+func verifyInterfaceMethodRecvs(t *testing.T, named *types.Named, level int) {
+	// avoid endless recursion in case of an embedding bug that lead to a cycle
+	if level > 10 {
+		t.Errorf("%s: embeds itself", named)
+		return
+	}
+
+	iface, _ := named.Underlying().(*types.Interface)
+	if iface == nil {
+		return // not an interface
+	}
+
+	// check explicitly declared methods
+	for i := 0; i < iface.NumExplicitMethods(); i++ {
+		m := iface.ExplicitMethod(i)
+		recv := m.Type().(*types.Signature).Recv()
+		if recv == nil {
+			t.Errorf("%s: missing receiver type", m)
+			continue
+		}
+		if recv.Type() != named {
+			t.Errorf("%s: got recv type %s; want %s", m, recv.Type(), named)
+		}
+	}
+
+	// check embedded interfaces (they are named, too)
+	for i := 0; i < iface.NumEmbeddeds(); i++ {
+		// embedding of interfaces cannot have cycles; recursion will terminate
+		verifyInterfaceMethodRecvs(t, iface.Embedded(i), level+1)
+	}
+}
+
+func TestReimport(t *testing.T) {
+	if !testenv.HasSrc() {
+		t.Skip("no source code available")
+	}
+
+	// Reimporting a partially imported (incomplete) package is not supported (see issue #19337).
+	// Make sure we recognize the situation and report an error.
+
+	mathPkg := types.NewPackage("math", "math") // incomplete package
+	importer := New(&build.Default, token.NewFileSet(), map[string]*types.Package{mathPkg.Path(): mathPkg})
+	_, err := importer.ImportFrom("math", ".", 0)
+	if err == nil || !strings.HasPrefix(err.Error(), "reimport") {
+		t.Errorf("got %v; want reimport error", err)
+	}
+}
+
+func TestIssue20855(t *testing.T) {
+	if !testenv.HasSrc() {
+		t.Skip("no source code available")
+	}
+
+	pkg, err := importer.ImportFrom("go/internal/srcimporter/testdata/issue20855", ".", 0)
+	if err == nil || !strings.Contains(err.Error(), "missing function body") {
+		t.Fatalf("got unexpected or no error: %v", err)
+	}
+	if pkg == nil {
+		t.Error("got no package despite no hard errors")
+	}
+}
+
+func testImportPath(t *testing.T, pkgPath string) {
+	if !testenv.HasSrc() {
+		t.Skip("no source code available")
+	}
+
+	pkgName := path.Base(pkgPath)
+
+	pkg, err := importer.Import(pkgPath)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if pkg.Name() != pkgName {
+		t.Errorf("got %q; want %q", pkg.Name(), pkgName)
+	}
+
+	if pkg.Path() != pkgPath {
+		t.Errorf("got %q; want %q", pkg.Path(), pkgPath)
+	}
+}
+
+// TestIssue23092 tests relative imports.
+func TestIssue23092(t *testing.T) {
+	testImportPath(t, "./testdata/issue23092")
+}
+
+// TestIssue24392 tests imports against a path containing 'testdata'.
+func TestIssue24392(t *testing.T) {
+	testImportPath(t, "go/internal/srcimporter/testdata/issue24392")
+}
+
+func TestCgo(t *testing.T) {
+	testenv.MustHaveGoBuild(t)
+	testenv.MustHaveCGO(t)
+
+	importer := New(&build.Default, token.NewFileSet(), make(map[string]*types.Package))
+	_, err := importer.ImportFrom("./misc/cgo/test", runtime.GOROOT(), 0)
+	if err != nil {
+		t.Fatalf("Import failed: %v", err)
+	}
+}
diff --git a/src/go/internal/srcimporter/testdata/issue20855/issue20855.go b/src/go/internal/srcimporter/testdata/issue20855/issue20855.go
new file mode 100644
index 0000000..d55448b
--- /dev/null
+++ b/src/go/internal/srcimporter/testdata/issue20855/issue20855.go
@@ -0,0 +1,7 @@
+// 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 issue20855
+
+func init() // "missing function body" is a soft error
diff --git a/src/go/internal/srcimporter/testdata/issue23092/issue23092.go b/src/go/internal/srcimporter/testdata/issue23092/issue23092.go
new file mode 100644
index 0000000..608698b
--- /dev/null
+++ b/src/go/internal/srcimporter/testdata/issue23092/issue23092.go
@@ -0,0 +1,5 @@
+// Copyright 2018 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 issue23092
diff --git a/src/go/internal/srcimporter/testdata/issue24392/issue24392.go b/src/go/internal/srcimporter/testdata/issue24392/issue24392.go
new file mode 100644
index 0000000..8ad5221
--- /dev/null
+++ b/src/go/internal/srcimporter/testdata/issue24392/issue24392.go
@@ -0,0 +1,5 @@
+// Copyright 2018 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 issue24392