Adding upstream version 1.21.8.upstream/1.21.8

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

2 files changed, 761 insertions, 0 deletions

diff --git a/src/cmd/go/internal/generate/generate.go b/src/cmd/go/internal/generate/generate.go
new file mode 100644
index 0000000..353506f
--- /dev/null
+++ b/src/cmd/go/internal/generate/generate.go
@@ -0,0 +1,502 @@
+// 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 generate implements the “go generate” command.
+package generate
+
+import (
+	"bufio"
+	"bytes"
+	"context"
+	"fmt"
+	"go/parser"
+	"go/token"
+	"io"
+	"log"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"regexp"
+	"slices"
+	"strconv"
+	"strings"
+
+	"cmd/go/internal/base"
+	"cmd/go/internal/cfg"
+	"cmd/go/internal/load"
+	"cmd/go/internal/modload"
+	"cmd/go/internal/str"
+	"cmd/go/internal/work"
+)
+
+var CmdGenerate = &base.Command{
+	Run:       runGenerate,
+	UsageLine: "go generate [-run regexp] [-n] [-v] [-x] [build flags] [file.go... | packages]",
+	Short:     "generate Go files by processing source",
+	Long: `
+Generate runs commands described by directives within existing
+files. Those commands can run any process but the intent is to
+create or update Go source files.
+
+Go generate is never run automatically by go build, go test,
+and so on. It must be run explicitly.
+
+Go generate scans the file for directives, which are lines of
+the form,
+
+	//go:generate command argument...
+
+(note: no leading spaces and no space in "//go") where command
+is the generator to be run, corresponding to an executable file
+that can be run locally. It must either be in the shell path
+(gofmt), a fully qualified path (/usr/you/bin/mytool), or a
+command alias, described below.
+
+Note that go generate does not parse the file, so lines that look
+like directives in comments or multiline strings will be treated
+as directives.
+
+The arguments to the directive are space-separated tokens or
+double-quoted strings passed to the generator as individual
+arguments when it is run.
+
+Quoted strings use Go syntax and are evaluated before execution; a
+quoted string appears as a single argument to the generator.
+
+To convey to humans and machine tools that code is generated,
+generated source should have a line that matches the following
+regular expression (in Go syntax):
+
+	^// Code generated .* DO NOT EDIT\.$
+
+This line must appear before the first non-comment, non-blank
+text in the file.
+
+Go generate sets several variables when it runs the generator:
+
+	$GOARCH
+		The execution architecture (arm, amd64, etc.)
+	$GOOS
+		The execution operating system (linux, windows, etc.)
+	$GOFILE
+		The base name of the file.
+	$GOLINE
+		The line number of the directive in the source file.
+	$GOPACKAGE
+		The name of the package of the file containing the directive.
+	$GOROOT
+		The GOROOT directory for the 'go' command that invoked the
+		generator, containing the Go toolchain and standard library.
+	$DOLLAR
+		A dollar sign.
+	$PATH
+		The $PATH of the parent process, with $GOROOT/bin
+		placed at the beginning. This causes generators
+		that execute 'go' commands to use the same 'go'
+		as the parent 'go generate' command.
+
+Other than variable substitution and quoted-string evaluation, no
+special processing such as "globbing" is performed on the command
+line.
+
+As a last step before running the command, any invocations of any
+environment variables with alphanumeric names, such as $GOFILE or
+$HOME, are expanded throughout the command line. The syntax for
+variable expansion is $NAME on all operating systems. Due to the
+order of evaluation, variables are expanded even inside quoted
+strings. If the variable NAME is not set, $NAME expands to the
+empty string.
+
+A directive of the form,
+
+	//go:generate -command xxx args...
+
+specifies, for the remainder of this source file only, that the
+string xxx represents the command identified by the arguments. This
+can be used to create aliases or to handle multiword generators.
+For example,
+
+	//go:generate -command foo go tool foo
+
+specifies that the command "foo" represents the generator
+"go tool foo".
+
+Generate processes packages in the order given on the command line,
+one at a time. If the command line lists .go files from a single directory,
+they are treated as a single package. Within a package, generate processes the
+source files in a package in file name order, one at a time. Within
+a source file, generate runs generators in the order they appear
+in the file, one at a time. The go generate tool also sets the build
+tag "generate" so that files may be examined by go generate but ignored
+during build.
+
+For packages with invalid code, generate processes only source files with a
+valid package clause.
+
+If any generator returns an error exit status, "go generate" skips
+all further processing for that package.
+
+The generator is run in the package's source directory.
+
+Go generate accepts two specific flags:
+
+	-run=""
+		if non-empty, specifies a regular expression to select
+		directives whose full original source text (excluding
+		any trailing spaces and final newline) matches the
+		expression.
+
+	-skip=""
+		if non-empty, specifies a regular expression to suppress
+		directives whose full original source text (excluding
+		any trailing spaces and final newline) matches the
+		expression. If a directive matches both the -run and
+		the -skip arguments, it is skipped.
+
+It also accepts the standard build flags including -v, -n, and -x.
+The -v flag prints the names of packages and files as they are
+processed.
+The -n flag prints commands that would be executed.
+The -x flag prints commands as they are executed.
+
+For more about build flags, see 'go help build'.
+
+For more about specifying packages, see 'go help packages'.
+	`,
+}
+
+var (
+	generateRunFlag string         // generate -run flag
+	generateRunRE   *regexp.Regexp // compiled expression for -run
+
+	generateSkipFlag string         // generate -skip flag
+	generateSkipRE   *regexp.Regexp // compiled expression for -skip
+)
+
+func init() {
+	work.AddBuildFlags(CmdGenerate, work.DefaultBuildFlags)
+	CmdGenerate.Flag.StringVar(&generateRunFlag, "run", "", "")
+	CmdGenerate.Flag.StringVar(&generateSkipFlag, "skip", "", "")
+}
+
+func runGenerate(ctx context.Context, cmd *base.Command, args []string) {
+	modload.InitWorkfile()
+
+	if generateRunFlag != "" {
+		var err error
+		generateRunRE, err = regexp.Compile(generateRunFlag)
+		if err != nil {
+			log.Fatalf("generate: %s", err)
+		}
+	}
+	if generateSkipFlag != "" {
+		var err error
+		generateSkipRE, err = regexp.Compile(generateSkipFlag)
+		if err != nil {
+			log.Fatalf("generate: %s", err)
+		}
+	}
+
+	cfg.BuildContext.BuildTags = append(cfg.BuildContext.BuildTags, "generate")
+
+	// Even if the arguments are .go files, this loop suffices.
+	printed := false
+	pkgOpts := load.PackageOpts{IgnoreImports: true}
+	for _, pkg := range load.PackagesAndErrors(ctx, pkgOpts, args) {
+		if modload.Enabled() && pkg.Module != nil && !pkg.Module.Main {
+			if !printed {
+				fmt.Fprintf(os.Stderr, "go: not generating in packages in dependency modules\n")
+				printed = true
+			}
+			continue
+		}
+
+		for _, file := range pkg.InternalGoFiles() {
+			if !generate(file) {
+				break
+			}
+		}
+
+		for _, file := range pkg.InternalXGoFiles() {
+			if !generate(file) {
+				break
+			}
+		}
+	}
+}
+
+// generate runs the generation directives for a single file.
+func generate(absFile string) bool {
+	src, err := os.ReadFile(absFile)
+	if err != nil {
+		log.Fatalf("generate: %s", err)
+	}
+
+	// Parse package clause
+	filePkg, err := parser.ParseFile(token.NewFileSet(), "", src, parser.PackageClauseOnly)
+	if err != nil {
+		// Invalid package clause - ignore file.
+		return true
+	}
+
+	g := &Generator{
+		r:        bytes.NewReader(src),
+		path:     absFile,
+		pkg:      filePkg.Name.String(),
+		commands: make(map[string][]string),
+	}
+	return g.run()
+}
+
+// A Generator represents the state of a single Go source file
+// being scanned for generator commands.
+type Generator struct {
+	r        io.Reader
+	path     string // full rooted path name.
+	dir      string // full rooted directory of file.
+	file     string // base name of file.
+	pkg      string
+	commands map[string][]string
+	lineNum  int // current line number.
+	env      []string
+}
+
+// run runs the generators in the current file.
+func (g *Generator) run() (ok bool) {
+	// Processing below here calls g.errorf on failure, which does panic(stop).
+	// If we encounter an error, we abort the package.
+	defer func() {
+		e := recover()
+		if e != nil {
+			ok = false
+			if e != stop {
+				panic(e)
+			}
+			base.SetExitStatus(1)
+		}
+	}()
+	g.dir, g.file = filepath.Split(g.path)
+	g.dir = filepath.Clean(g.dir) // No final separator please.
+	if cfg.BuildV {
+		fmt.Fprintf(os.Stderr, "%s\n", base.ShortPath(g.path))
+	}
+
+	// Scan for lines that start "//go:generate".
+	// Can't use bufio.Scanner because it can't handle long lines,
+	// which are likely to appear when using generate.
+	input := bufio.NewReader(g.r)
+	var err error
+	// One line per loop.
+	for {
+		g.lineNum++ // 1-indexed.
+		var buf []byte
+		buf, err = input.ReadSlice('\n')
+		if err == bufio.ErrBufferFull {
+			// Line too long - consume and ignore.
+			if isGoGenerate(buf) {
+				g.errorf("directive too long")
+			}
+			for err == bufio.ErrBufferFull {
+				_, err = input.ReadSlice('\n')
+			}
+			if err != nil {
+				break
+			}
+			continue
+		}
+
+		if err != nil {
+			// Check for marker at EOF without final \n.
+			if err == io.EOF && isGoGenerate(buf) {
+				err = io.ErrUnexpectedEOF
+			}
+			break
+		}
+
+		if !isGoGenerate(buf) {
+			continue
+		}
+		if generateRunFlag != "" && !generateRunRE.Match(bytes.TrimSpace(buf)) {
+			continue
+		}
+		if generateSkipFlag != "" && generateSkipRE.Match(bytes.TrimSpace(buf)) {
+			continue
+		}
+
+		g.setEnv()
+		words := g.split(string(buf))
+		if len(words) == 0 {
+			g.errorf("no arguments to directive")
+		}
+		if words[0] == "-command" {
+			g.setShorthand(words)
+			continue
+		}
+		// Run the command line.
+		if cfg.BuildN || cfg.BuildX {
+			fmt.Fprintf(os.Stderr, "%s\n", strings.Join(words, " "))
+		}
+		if cfg.BuildN {
+			continue
+		}
+		g.exec(words)
+	}
+	if err != nil && err != io.EOF {
+		g.errorf("error reading %s: %s", base.ShortPath(g.path), err)
+	}
+	return true
+}
+
+func isGoGenerate(buf []byte) bool {
+	return bytes.HasPrefix(buf, []byte("//go:generate ")) || bytes.HasPrefix(buf, []byte("//go:generate\t"))
+}
+
+// setEnv sets the extra environment variables used when executing a
+// single go:generate command.
+func (g *Generator) setEnv() {
+	env := []string{
+		"GOROOT=" + cfg.GOROOT,
+		"GOARCH=" + cfg.BuildContext.GOARCH,
+		"GOOS=" + cfg.BuildContext.GOOS,
+		"GOFILE=" + g.file,
+		"GOLINE=" + strconv.Itoa(g.lineNum),
+		"GOPACKAGE=" + g.pkg,
+		"DOLLAR=" + "$",
+	}
+	env = base.AppendPATH(env)
+	env = base.AppendPWD(env, g.dir)
+	g.env = env
+}
+
+// split breaks the line into words, evaluating quoted
+// strings and evaluating environment variables.
+// The initial //go:generate element is present in line.
+func (g *Generator) split(line string) []string {
+	// Parse line, obeying quoted strings.
+	var words []string
+	line = line[len("//go:generate ") : len(line)-1] // Drop preamble and final newline.
+	// There may still be a carriage return.
+	if len(line) > 0 && line[len(line)-1] == '\r' {
+		line = line[:len(line)-1]
+	}
+	// One (possibly quoted) word per iteration.
+Words:
+	for {
+		line = strings.TrimLeft(line, " \t")
+		if len(line) == 0 {
+			break
+		}
+		if line[0] == '"' {
+			for i := 1; i < len(line); i++ {
+				c := line[i] // Only looking for ASCII so this is OK.
+				switch c {
+				case '\\':
+					if i+1 == len(line) {
+						g.errorf("bad backslash")
+					}
+					i++ // Absorb next byte (If it's a multibyte we'll get an error in Unquote).
+				case '"':
+					word, err := strconv.Unquote(line[0 : i+1])
+					if err != nil {
+						g.errorf("bad quoted string")
+					}
+					words = append(words, word)
+					line = line[i+1:]
+					// Check the next character is space or end of line.
+					if len(line) > 0 && line[0] != ' ' && line[0] != '\t' {
+						g.errorf("expect space after quoted argument")
+					}
+					continue Words
+				}
+			}
+			g.errorf("mismatched quoted string")
+		}
+		i := strings.IndexAny(line, " \t")
+		if i < 0 {
+			i = len(line)
+		}
+		words = append(words, line[0:i])
+		line = line[i:]
+	}
+	// Substitute command if required.
+	if len(words) > 0 && g.commands[words[0]] != nil {
+		// Replace 0th word by command substitution.
+		//
+		// Force a copy of the command definition to
+		// ensure words doesn't end up as a reference
+		// to the g.commands content.
+		tmpCmdWords := append([]string(nil), (g.commands[words[0]])...)
+		words = append(tmpCmdWords, words[1:]...)
+	}
+	// Substitute environment variables.
+	for i, word := range words {
+		words[i] = os.Expand(word, g.expandVar)
+	}
+	return words
+}
+
+var stop = fmt.Errorf("error in generation")
+
+// errorf logs an error message prefixed with the file and line number.
+// It then exits the program (with exit status 1) because generation stops
+// at the first error.
+func (g *Generator) errorf(format string, args ...any) {
+	fmt.Fprintf(os.Stderr, "%s:%d: %s\n", base.ShortPath(g.path), g.lineNum,
+		fmt.Sprintf(format, args...))
+	panic(stop)
+}
+
+// expandVar expands the $XXX invocation in word. It is called
+// by os.Expand.
+func (g *Generator) expandVar(word string) string {
+	w := word + "="
+	for _, e := range g.env {
+		if strings.HasPrefix(e, w) {
+			return e[len(w):]
+		}
+	}
+	return os.Getenv(word)
+}
+
+// setShorthand installs a new shorthand as defined by a -command directive.
+func (g *Generator) setShorthand(words []string) {
+	// Create command shorthand.
+	if len(words) == 1 {
+		g.errorf("no command specified for -command")
+	}
+	command := words[1]
+	if g.commands[command] != nil {
+		g.errorf("command %q multiply defined", command)
+	}
+	g.commands[command] = slices.Clip(words[2:])
+}
+
+// exec runs the command specified by the argument. The first word is
+// the command name itself.
+func (g *Generator) exec(words []string) {
+	path := words[0]
+	if path != "" && !strings.Contains(path, string(os.PathSeparator)) {
+		// If a generator says '//go:generate go run <blah>' it almost certainly
+		// intends to use the same 'go' as 'go generate' itself.
+		// Prefer to resolve the binary from GOROOT/bin, and for consistency
+		// prefer to resolve any other commands there too.
+		gorootBinPath, err := exec.LookPath(filepath.Join(cfg.GOROOTbin, path))
+		if err == nil {
+			path = gorootBinPath
+		}
+	}
+	cmd := exec.Command(path, words[1:]...)
+	cmd.Args[0] = words[0] // Overwrite with the original in case it was rewritten above.
+
+	// Standard in and out of generator should be the usual.
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	// Run the command in the package directory.
+	cmd.Dir = g.dir
+	cmd.Env = str.StringList(cfg.OrigEnv, g.env)
+	err := cmd.Run()
+	if err != nil {
+		g.errorf("running %q: %s", words[0], err)
+	}
+}
diff --git a/src/cmd/go/internal/generate/generate_test.go b/src/cmd/go/internal/generate/generate_test.go
new file mode 100644
index 0000000..d61ecf1
--- /dev/null
+++ b/src/cmd/go/internal/generate/generate_test.go
@@ -0,0 +1,259 @@
+// 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 generate
+
+import (
+	"internal/testenv"
+	"os"
+	"path/filepath"
+	"reflect"
+	"runtime"
+	"testing"
+)
+
+type splitTest struct {
+	in  string
+	out []string
+}
+
+// Same as above, except including source line number to set
+type splitTestWithLine struct {
+	in         string
+	out        []string
+	lineNumber int
+}
+
+const anyLineNo = 0
+
+var splitTests = []splitTest{
+	{"", nil},
+	{"x", []string{"x"}},
+	{" a b\tc ", []string{"a", "b", "c"}},
+	{` " a " `, []string{" a "}},
+	{"$GOARCH", []string{runtime.GOARCH}},
+	{"$GOOS", []string{runtime.GOOS}},
+	{"$GOFILE", []string{"proc.go"}},
+	{"$GOPACKAGE", []string{"sys"}},
+	{"a $XXNOTDEFINEDXX b", []string{"a", "", "b"}},
+	{"/$XXNOTDEFINED/", []string{"//"}},
+	{"/$DOLLAR/", []string{"/$/"}},
+	{"yacc -o $GOARCH/yacc_$GOFILE", []string{"go", "tool", "yacc", "-o", runtime.GOARCH + "/yacc_proc.go"}},
+}
+
+func TestGenerateCommandParse(t *testing.T) {
+	dir := filepath.Join(testenv.GOROOT(t), "src", "sys")
+	g := &Generator{
+		r:        nil, // Unused here.
+		path:     filepath.Join(dir, "proc.go"),
+		dir:      dir,
+		file:     "proc.go",
+		pkg:      "sys",
+		commands: make(map[string][]string),
+	}
+	g.setEnv()
+	g.setShorthand([]string{"-command", "yacc", "go", "tool", "yacc"})
+	for _, test := range splitTests {
+		// First with newlines.
+		got := g.split("//go:generate " + test.in + "\n")
+		if !reflect.DeepEqual(got, test.out) {
+			t.Errorf("split(%q): got %q expected %q", test.in, got, test.out)
+		}
+		// Then with CRLFs, thank you Windows.
+		got = g.split("//go:generate " + test.in + "\r\n")
+		if !reflect.DeepEqual(got, test.out) {
+			t.Errorf("split(%q): got %q expected %q", test.in, got, test.out)
+		}
+	}
+}
+
+// These environment variables will be undefined before the splitTestWithLine tests
+var undefEnvList = []string{
+	"_XYZZY_",
+}
+
+// These environment variables will be defined before the splitTestWithLine tests
+var defEnvMap = map[string]string{
+	"_PLUGH_": "SomeVal",
+	"_X":      "Y",
+}
+
+// TestGenerateCommandShortHand - similar to TestGenerateCommandParse,
+// except:
+//  1. if the result starts with -command, record that shorthand
+//     before moving on to the next test.
+//  2. If a source line number is specified, set that in the parser
+//     before executing the test.  i.e., execute the split as if it
+//     processing that source line.
+func TestGenerateCommandShorthand(t *testing.T) {
+	dir := filepath.Join(testenv.GOROOT(t), "src", "sys")
+	g := &Generator{
+		r:        nil, // Unused here.
+		path:     filepath.Join(dir, "proc.go"),
+		dir:      dir,
+		file:     "proc.go",
+		pkg:      "sys",
+		commands: make(map[string][]string),
+	}
+
+	var inLine string
+	var expected, got []string
+
+	g.setEnv()
+
+	// Set up the system environment variables
+	for i := range undefEnvList {
+		os.Unsetenv(undefEnvList[i])
+	}
+	for k := range defEnvMap {
+		os.Setenv(k, defEnvMap[k])
+	}
+
+	// simple command from environment variable
+	inLine = "//go:generate -command CMD0 \"ab${_X}cd\""
+	expected = []string{"-command", "CMD0", "abYcd"}
+	got = g.split(inLine + "\n")
+
+	if !reflect.DeepEqual(got, expected) {
+		t.Errorf("split(%q): got %q expected %q", inLine, got, expected)
+	}
+
+	// try again, with an extra level of indirection (should leave variable in command)
+	inLine = "//go:generate -command CMD0 \"ab${DOLLAR}{_X}cd\""
+	expected = []string{"-command", "CMD0", "ab${_X}cd"}
+	got = g.split(inLine + "\n")
+
+	if !reflect.DeepEqual(got, expected) {
+		t.Errorf("split(%q): got %q expected %q", inLine, got, expected)
+	}
+
+	// Now the interesting part, record that output as a command
+	g.setShorthand(got)
+
+	// see that the command still substitutes correctly from env. variable
+	inLine = "//go:generate CMD0"
+	expected = []string{"abYcd"}
+	got = g.split(inLine + "\n")
+
+	if !reflect.DeepEqual(got, expected) {
+		t.Errorf("split(%q): got %q expected %q", inLine, got, expected)
+	}
+
+	// Now change the value of $X and see if the recorded definition is
+	// still intact (vs. having the $_X already substituted out)
+
+	os.Setenv("_X", "Z")
+	inLine = "//go:generate CMD0"
+	expected = []string{"abZcd"}
+	got = g.split(inLine + "\n")
+
+	if !reflect.DeepEqual(got, expected) {
+		t.Errorf("split(%q): got %q expected %q", inLine, got, expected)
+	}
+
+	// What if the variable is now undefined?  Should be empty substitution.
+
+	os.Unsetenv("_X")
+	inLine = "//go:generate CMD0"
+	expected = []string{"abcd"}
+	got = g.split(inLine + "\n")
+
+	if !reflect.DeepEqual(got, expected) {
+		t.Errorf("split(%q): got %q expected %q", inLine, got, expected)
+	}
+
+	// Try another undefined variable as an extra check
+	os.Unsetenv("_Z")
+	inLine = "//go:generate -command CMD1 \"ab${_Z}cd\""
+	expected = []string{"-command", "CMD1", "abcd"}
+	got = g.split(inLine + "\n")
+
+	if !reflect.DeepEqual(got, expected) {
+		t.Errorf("split(%q): got %q expected %q", inLine, got, expected)
+	}
+
+	g.setShorthand(got)
+
+	inLine = "//go:generate CMD1"
+	expected = []string{"abcd"}
+	got = g.split(inLine + "\n")
+
+	if !reflect.DeepEqual(got, expected) {
+		t.Errorf("split(%q): got %q expected %q", inLine, got, expected)
+	}
+
+	const val = "someNewValue"
+	os.Setenv("_Z", val)
+
+	// try again with the properly-escaped variable.
+
+	inLine = "//go:generate -command CMD2 \"ab${DOLLAR}{_Z}cd\""
+	expected = []string{"-command", "CMD2", "ab${_Z}cd"}
+	got = g.split(inLine + "\n")
+
+	if !reflect.DeepEqual(got, expected) {
+		t.Errorf("split(%q): got %q expected %q", inLine, got, expected)
+	}
+
+	g.setShorthand(got)
+
+	inLine = "//go:generate CMD2"
+	expected = []string{"ab" + val + "cd"}
+	got = g.split(inLine + "\n")
+
+	if !reflect.DeepEqual(got, expected) {
+		t.Errorf("split(%q): got %q expected %q", inLine, got, expected)
+	}
+}
+
+// Command-related tests for TestGenerateCommandShortHand2
+// -- Note line numbers included to check substitutions from "build-in" variable - $GOLINE
+var splitTestsLines = []splitTestWithLine{
+	{"-command TEST1 $GOLINE", []string{"-command", "TEST1", "22"}, 22},
+	{"-command TEST2 ${DOLLAR}GOLINE", []string{"-command", "TEST2", "$GOLINE"}, 26},
+	{"TEST1", []string{"22"}, 33},
+	{"TEST2", []string{"66"}, 66},
+	{"TEST1 ''", []string{"22", "''"}, 99},
+	{"TEST2 ''", []string{"44", "''"}, 44},
+}
+
+// TestGenerateCommandShortHand - similar to TestGenerateCommandParse,
+// except:
+//  1. if the result starts with -command, record that shorthand
+//     before moving on to the next test.
+//  2. If a source line number is specified, set that in the parser
+//     before executing the test.  i.e., execute the split as if it
+//     processing that source line.
+func TestGenerateCommandShortHand2(t *testing.T) {
+	dir := filepath.Join(testenv.GOROOT(t), "src", "sys")
+	g := &Generator{
+		r:        nil, // Unused here.
+		path:     filepath.Join(dir, "proc.go"),
+		dir:      dir,
+		file:     "proc.go",
+		pkg:      "sys",
+		commands: make(map[string][]string),
+	}
+	g.setEnv()
+	for _, test := range splitTestsLines {
+		// if the test specified a line number, reflect that
+		if test.lineNumber != anyLineNo {
+			g.lineNum = test.lineNumber
+			g.setEnv()
+		}
+		// First with newlines.
+		got := g.split("//go:generate " + test.in + "\n")
+		if !reflect.DeepEqual(got, test.out) {
+			t.Errorf("split(%q): got %q expected %q", test.in, got, test.out)
+		}
+		// Then with CRLFs, thank you Windows.
+		got = g.split("//go:generate " + test.in + "\r\n")
+		if !reflect.DeepEqual(got, test.out) {
+			t.Errorf("split(%q): got %q expected %q", test.in, got, test.out)
+		}
+		if got[0] == "-command" { // record commands
+			g.setShorthand(got)
+		}
+	}
+}