*context = build.Default
	context.Dir = filepath.Join(testenv.GOROOT(t), "src")

	w := NewWalker(context, context.Dir)
	for _, pkg := range w.stdPackages {
		if strings.HasPrefix(pkg, "vendor/") || strings.HasPrefix(pkg, "golang.org/x/") {
			t.Fatalf("stdPackages contains unexpected package %s", pkg)
		}
	}
}

func TestIssue64958(t *testing.T) {
	defer func() {
		if x := recover(); x != nil {

					break
				}
				// Fall through in the unlikely case
				// that filter at some point is
				// "Pid:\t".
			}
			if strings.HasPrefix(line, filter) {
				if line == expected {
					foundAThread = true
					break
				}
				if filter == "Groups:" && strings.HasPrefix(line, "Groups:\t") {
					// https://github.com/golang/go/issues/46145

func cname(s string) string {
	if t, ok := nameToC[s]; ok {
		return t
	}

	if strings.HasPrefix(s, "struct_") {
		return "struct " + s[len("struct_"):]
	}
	if strings.HasPrefix(s, "union_") {
		return "union " + s[len("union_"):]
	}
	if strings.HasPrefix(s, "enum_") {
		return "enum " + s[len("enum_"):]
	}
	if strings.HasPrefix(s, "sizeof_") {
		return "sizeof(" + cname(s[len("sizeof_"):]) + ")"
	}
	return s
}

			continue
		}
		// In module mode, this package has a fully-qualified import path.
		// Remove it if present.
		fname = strings.TrimPrefix(fname, "cmd/cgo/internal/")
		if !strings.HasPrefix(fname, "test.") {
			continue
		}
		got = append(got, fname)
	}
	if !reflect.DeepEqual(want, got) {
		t.Errorf("incorrect backtrace:\nwant:\t%v\ngot:\t%v", want, got)
	}

	// Output: Fields are: ["foo1" "bar2" "baz3"]
}

func ExampleHasPrefix() {
	fmt.Println(bytes.HasPrefix([]byte("Gopher"), []byte("Go")))
	fmt.Println(bytes.HasPrefix([]byte("Gopher"), []byte("C")))
	fmt.Println(bytes.HasPrefix([]byte("Gopher"), []byte("")))
	// Output:
	// true
	// false
	// true
}

func ExampleHasSuffix() {

func (f *File) saveExport(x interface{}, context astContext) {
	n, ok := x.(*ast.FuncDecl)
	if !ok {
		return
	}

	if n.Doc == nil {
		return
	}
	for _, c := range n.Doc.List {
		if !strings.HasPrefix(c.Text, "//export ") {
			continue
		}

		name := strings.TrimSpace(c.Text[9:])
		if name == "" {
			error_(c.Pos(), "export missing name")
		}

		if name != n.Name.Name {

					!strings.Contains(test.input, "<>")

				wantName := ""
				if isFuncSym {
					// Strip $|* and (SB) and +Int.
					wantName = test.output[:len(test.output)-4]
					if strings.HasPrefix(wantName, "$") || strings.HasPrefix(wantName, "*") {
						wantName = wantName[1:]
					}
					if i := strings.Index(wantName, "+"); i >= 0 {
						wantName = wantName[:i]
					}
				}

	b := bytealg.MakeNoZero(n)[:n:n]
	bp := copy(b, s[0])
	for _, v := range s[1:] {
		bp += copy(b[bp:], sep)
		bp += copy(b[bp:], v)
	}
	return b
}

// HasPrefix reports whether the byte slice s begins with prefix.
func HasPrefix(s, prefix []byte) bool {
	return len(s) >= len(prefix) && Equal(s[0:len(prefix)], prefix)
}

// HasSuffix reports whether the byte slice s ends with suffix.

	lines := strings.SplitAfter(string(data), "\n")
Diff:
	for _, line := range lines {
		lineno++

		// Ignore include of textflag.h.
		if strings.HasPrefix(line, "#include ") {
			continue
		}

		// Ignore GLOBL.
		if strings.HasPrefix(line, "GLOBL ") {
			continue
		}

		// The general form of a test input line is:
		//	// comment
		//	INST args [// printed form] [// hex encoding]

		exitCode = 1
	}
	if filepath.Base(filename) == "go1.4.txt" {
		// No use for blank lines in api files, except go1.4.txt
		// used them in a reasonable way and we should let it be.
	} else if strings.HasPrefix(s, "\n") || strings.Contains(s, "\n\n") {
		log.Printf("%s: contains a blank line", filename)
		exitCode = 1
	}
	if s == "" {
		log.Printf("%s: empty file", filename)
		exitCode = 1