td, err := os.Open("testdata/src/pkg")
	if err != nil {
		t.Fatal(err)
	}
	fis, err := td.Readdir(0)
	if err != nil {
		t.Fatal(err)
	}
	for _, fi := range fis {
		if !fi.IsDir() {
			continue
		}

		// TODO(gri) remove extra pkg directory eventually
		goldenFile := filepath.Join("testdata", "src", "pkg", fi.Name(), "golden.txt")
		w := NewWalker(nil, "testdata/src/pkg")
		pkg, _ := w.import_(fi.Name())

Vendoring in std and cmd
========================

The Go command maintains copies of external packages needed by the
standard library in the src/vendor and src/cmd/vendor directories.

There are two modules, std and cmd, defined in src/go.mod and
src/cmd/go.mod. When a package outside std or cmd is imported
by a package inside std or cmd, the import path is interpreted
as if it had a "vendor/" prefix. For example, within "crypto/tls",

//
// This function mutates src and returns a normalized map where:
//   - adjacent fragments are coalesced together
//   - only the last fragment may be empty
//   - the endOffset of the last fragment is the total size
func invertSparseEntries(src []sparseEntry, size int64) []sparseEntry {
	dst := src[:0]
	var pre sparseEntry
	for _, cur := range src {
		if cur.Length == 0 {

# Use of this source code is governed by a BSD-style
# license that can be found in the LICENSE file.

set -e
if [ ! -f make.bash ]; then
	echo 'all.bash must be run from $GOROOT/src' 1>&2
	exit 1
fi
. ./make.bash "$@" --no-banner
bash run.bash --no-rebuild

file. This allows pre-compiled static libraries to be included in the package
directory and linked properly.
For example if package foo is in the directory /go/src/foo:

	// #cgo LDFLAGS: -L${SRCDIR}/libs -lfoo

Will be expanded to:

	// #cgo LDFLAGS: -L/go/src/foo/libs -lfoo

When the Go tool sees that one or more Go files use the special import
"C", it will look for other non-Go files in the directory and compile

	for i := 2; ; i++ {
		ch <- i  // Send 'i' to channel 'ch'.
	}
}

// Copy the values from channel 'src' to channel 'dst',
// removing those divisible by 'prime'.
func filter(src <-chan int, dst chan<- int, prime int) {
	for i := range src {  // Loop over values received from 'src'.
		if i%prime != 0 {
			dst <- i  // Send 'i' to channel 'dst'.
		}
	}
}

Files in this directory are data for Go's API checker ("go tool api", in src/cmd/api).

Each file is a list of API features, one per line.

go1.txt (and similarly named files) are frozen once a version has been
shipped. Each file adds new lines but does not remove any.

except.txt lists features that may disappear without breaking true
compatibility.

Starting with go1.19.txt, each API feature line must end in "#nnnnn"

// string to a slice of bytes.) The source and destination may overlap. Copy
// returns the number of elements copied, which will be the minimum of
// len(src) and len(dst).
func copy(dst, src []Type) int

// The delete built-in function deletes the element with the specified key
// (m[key]) from the map. If m is nil or there is no such element, delete
// is a no-op.

	}
	fmt.Fprintf(p.errorWriter, format, args...)
	p.errorCount++
	if p.errorCount > 10 && !*flags.AllErrors {
		log.Fatal("too many errors")
	}
}

func (p *Parser) pos() src.XPos {
	return p.ctxt.PosTable.XPos(src.MakePos(p.lex.Base(), uint(p.lineNum), 0))
}

func (p *Parser) Parse() (*obj.Prog, bool) {
	scratch := make([][]lex.Token, 0, 3)
	for {
		word, cond, operands, ok := p.line(scratch)

# so this script no longer runs in any automated fashion.
#
# Options:
#   -e: stop at first failure

if [ ! -f run.bash ]; then
	echo 'buildall.bash must be run from $GOROOT/src' 1>&2
	exit 1
fi

sete=false
if [ "$1" = "-e" ]; then
	sete=true
	shift
fi

if [ "$sete" = true ]; then
	set -e
fi

pattern="$1"
if [ "$pattern" = "" ]; then
	pattern=.
fi