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mirror of https://github.com/golang/go synced 2024-11-05 17:26:11 -07:00

os/exec: simplify Windows-specific tests

- Use the test binary itself for printing paths instead of building a
  separate binary and running it through additional subprocesses.

- Factor out a common chdir helper.

- Use t.Setenv where appropriate.

- Reduce indirection in test helpers.

- Set NoDefaultCurrentDirectoryInExePath consistently in the
  environment.

Also add a test case demonstrating an interesting behavior for
relative paths that may interact with #62596.

Fixes #62594.
For #62596.

Change-Id: I19b9325034edf78cd0ca747594476cd7432bb451
Reviewed-on: https://go-review.googlesource.com/c/go/+/528035
Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Bryan Mills <bcmills@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
This commit is contained in:
Bryan C. Mills 2023-09-12 14:50:50 -04:00 committed by Gopher Robot
parent dd2279ee34
commit 105f9d5169
4 changed files with 418 additions and 441 deletions

View File

@ -24,7 +24,7 @@ var pathVar string = func() string {
func TestLookPath(t *testing.T) {
testenv.MustHaveExec(t)
// Not parallel: uses os.Chdir and t.Setenv.
// Not parallel: uses Chdir and Setenv.
tmpDir := filepath.Join(t.TempDir(), "testdir")
if err := os.Mkdir(tmpDir, 0777); err != nil {
@ -38,18 +38,7 @@ func TestLookPath(t *testing.T) {
if err := os.WriteFile(filepath.Join(tmpDir, executable), []byte{1, 2, 3}, 0777); err != nil {
t.Fatal(err)
}
cwd, err := os.Getwd()
if err != nil {
t.Fatal(err)
}
defer func() {
if err := os.Chdir(cwd); err != nil {
panic(err)
}
}()
if err = os.Chdir(tmpDir); err != nil {
t.Fatal(err)
}
chdir(t, tmpDir)
t.Setenv("PWD", tmpDir)
t.Logf(". is %#q", tmpDir)

View File

@ -77,6 +77,21 @@ func TestMain(m *testing.M) {
if os.Getenv("GO_EXEC_TEST_PID") == "" {
os.Setenv("GO_EXEC_TEST_PID", strconv.Itoa(pid))
if runtime.GOOS == "windows" {
// Normalize environment so that test behavior is consistent.
// (The behavior of LookPath varies depending on this variable.)
//
// Ideally we would test both with the variable set and with it cleared,
// but I (bcmills) am not sure that that's feasible: it may already be set
// in the Windows registry, and I'm not sure if it is possible to remove
// a registry variable in a program's environment.
//
// Per https://learn.microsoft.com/en-us/windows/win32/api/processenv/nf-processenv-needcurrentdirectoryforexepathw#remarks,
// “the existence of the NoDefaultCurrentDirectoryInExePath environment
// variable is checked, and not its value.”
os.Setenv("NoDefaultCurrentDirectoryInExePath", "TRUE")
}
code := m.Run()
if code == 0 && flag.Lookup("test.run").Value.String() == "" && flag.Lookup("test.list").Value.String() == "" {
for cmd := range helperCommands {
@ -180,6 +195,28 @@ var exeOnce struct {
sync.Once
}
func chdir(t *testing.T, dir string) {
t.Helper()
prev, err := os.Getwd()
if err != nil {
t.Fatal(err)
}
if err := os.Chdir(dir); err != nil {
t.Fatal(err)
}
t.Logf("Chdir(%#q)", dir)
t.Cleanup(func() {
if err := os.Chdir(prev); err != nil {
// Couldn't chdir back to the original working directory.
// panic instead of t.Fatal so that we don't run other tests
// in an unexpected location.
panic("couldn't restore working directory: " + err.Error())
}
})
}
var helperCommandUsed sync.Map
var helperCommands = map[string]func(...string){

View File

@ -4,30 +4,19 @@
//go:build unix
package exec
package exec_test
import (
"os"
"os/exec"
"testing"
)
func TestLookPathUnixEmptyPath(t *testing.T) {
// Not parallel: uses os.Chdir.
// Not parallel: uses Chdir and Setenv.
tmp, err := os.MkdirTemp("", "TestLookPathUnixEmptyPath")
if err != nil {
t.Fatal("TempDir failed: ", err)
}
defer os.RemoveAll(tmp)
wd, err := os.Getwd()
if err != nil {
t.Fatal("Getwd failed: ", err)
}
err = os.Chdir(tmp)
if err != nil {
t.Fatal("Chdir failed: ", err)
}
defer os.Chdir(wd)
tmp := t.TempDir()
chdir(t, tmp)
f, err := os.OpenFile("exec_me", os.O_CREATE|os.O_EXCL, 0700)
if err != nil {
@ -40,7 +29,7 @@ func TestLookPathUnixEmptyPath(t *testing.T) {
t.Setenv("PATH", "")
path, err := LookPath("exec_me")
path, err := exec.LookPath("exec_me")
if err == nil {
t.Fatal("LookPath found exec_me in empty $PATH")
}

View File

@ -12,496 +12,435 @@ import (
"fmt"
"internal/testenv"
"io"
"io/fs"
"os"
"os/exec"
"path/filepath"
"strconv"
"slices"
"strings"
"testing"
)
func init() {
registerHelperCommand("exec", cmdExec)
registerHelperCommand("lookpath", cmdLookPath)
registerHelperCommand("printpath", cmdPrintPath)
}
func cmdLookPath(args ...string) {
p, err := exec.LookPath(args[0])
func cmdPrintPath(args ...string) {
exe, err := os.Executable()
if err != nil {
fmt.Fprintf(os.Stderr, "LookPath failed: %v\n", err)
fmt.Fprintf(os.Stderr, "Executable: %v\n", err)
os.Exit(1)
}
fmt.Print(p)
fmt.Println(exe)
}
func cmdExec(args ...string) {
cmd := exec.Command(args[1])
cmd.Dir = args[0]
if errors.Is(cmd.Err, exec.ErrDot) {
cmd.Err = nil
}
output, err := cmd.CombinedOutput()
if err != nil {
fmt.Fprintf(os.Stderr, "Child: %s %s", err, string(output))
os.Exit(1)
}
fmt.Printf("%s", output)
}
// installProgs creates executable files (or symlinks to executable files) at
// multiple destination paths. It uses root as prefix for all destination files.
func installProgs(t *testing.T, root string, files []string) {
for _, f := range files {
dstPath := filepath.Join(root, f)
func installExe(t *testing.T, dest, src string) {
fsrc, err := os.Open(src)
if err != nil {
t.Fatal("os.Open failed: ", err)
}
defer fsrc.Close()
fdest, err := os.Create(dest)
if err != nil {
t.Fatal("os.Create failed: ", err)
}
defer fdest.Close()
_, err = io.Copy(fdest, fsrc)
if err != nil {
t.Fatal("io.Copy failed: ", err)
dir := filepath.Dir(dstPath)
if err := os.MkdirAll(dir, 0755); err != nil {
t.Fatal(err)
}
if os.IsPathSeparator(f[len(f)-1]) {
continue // directory and PATH entry only.
}
if strings.EqualFold(filepath.Ext(f), ".bat") {
installBat(t, dstPath)
} else {
installExe(t, dstPath)
}
}
}
func installBat(t *testing.T, dest string) {
f, err := os.Create(dest)
// installExe installs a copy of the test executable
// at the given location, creating directories as needed.
//
// (We use a copy instead of just a symlink to ensure that os.Executable
// always reports an unambiguous path, regardless of how it is implemented.)
func installExe(t *testing.T, dstPath string) {
src, err := os.Open(exePath(t))
if err != nil {
t.Fatalf("failed to create batch file: %v", err)
t.Fatal(err)
}
defer src.Close()
dst, err := os.OpenFile(dstPath, os.O_CREATE|os.O_EXCL|os.O_WRONLY, 0o777)
if err != nil {
t.Fatal(err)
}
defer func() {
if err := dst.Close(); err != nil {
t.Fatal(err)
}
}()
_, err = io.Copy(dst, src)
if err != nil {
t.Fatal(err)
}
defer f.Close()
fmt.Fprintf(f, "@echo %s\n", dest)
}
func installProg(t *testing.T, dest, srcExe string) {
err := os.MkdirAll(filepath.Dir(dest), 0700)
// installBat creates a batch file at dst that prints its own
// path when run.
func installBat(t *testing.T, dstPath string) {
dst, err := os.OpenFile(dstPath, os.O_CREATE|os.O_EXCL|os.O_WRONLY, 0o777)
if err != nil {
t.Fatal("os.MkdirAll failed: ", err)
t.Fatal(err)
}
if strings.ToLower(filepath.Ext(dest)) == ".bat" {
installBat(t, dest)
return
defer func() {
if err := dst.Close(); err != nil {
t.Fatal(err)
}
}()
if _, err := fmt.Fprintf(dst, "@echo %s\r\n", dstPath); err != nil {
t.Fatal(err)
}
installExe(t, dest, srcExe)
}
type lookPathTest struct {
rootDir string
PATH string
PATHEXT string
files []string
name string
PATHEXT string // empty to use default
files []string // PATH contains all named directories
searchFor string
fails bool // test is expected to fail
}
func (test lookPathTest) runProg(t *testing.T, env []string, cmd *exec.Cmd) (string, error) {
cmd.Env = env
cmd.Dir = test.rootDir
args := append([]string(nil), cmd.Args...)
args[0] = filepath.Base(args[0])
cmdText := fmt.Sprintf("%q command", strings.Join(args, " "))
out, err := cmd.CombinedOutput()
if (err != nil) != test.fails {
if test.fails {
t.Fatalf("test=%+v: %s succeeded, but expected to fail", test, cmdText)
}
t.Fatalf("test=%+v: %s failed, but expected to succeed: %v - %v", test, cmdText, err, string(out))
}
if err != nil {
return "", fmt.Errorf("test=%+v: %s failed: %v - %v", test, cmdText, err, string(out))
}
// normalise program output
p := string(out)
// trim terminating \r and \n that batch file outputs
for len(p) > 0 && (p[len(p)-1] == '\n' || p[len(p)-1] == '\r') {
p = p[:len(p)-1]
}
if !filepath.IsAbs(p) {
return p, nil
}
if p[:len(test.rootDir)] != test.rootDir {
t.Fatalf("test=%+v: %s output is wrong: %q must have %q prefix", test, cmdText, p, test.rootDir)
}
return p[len(test.rootDir)+1:], nil
}
func updateEnv(env []string, name, value string) []string {
for i, e := range env {
if strings.HasPrefix(strings.ToUpper(e), name+"=") {
env[i] = name + "=" + value
return env
}
}
return append(env, name+"="+value)
}
func createEnv(dir, PATH, PATHEXT string) []string {
env := os.Environ()
env = updateEnv(env, "PATHEXT", PATHEXT)
// Add dir in front of every directory in the PATH.
dirs := filepath.SplitList(PATH)
for i := range dirs {
dirs[i] = filepath.Join(dir, dirs[i])
}
path := strings.Join(dirs, ";")
env = updateEnv(env, "PATH", os.Getenv("SystemRoot")+"/System32;"+path)
return env
}
// createFiles copies srcPath file into multiply files.
// It uses dir as prefix for all destination files.
func createFiles(t *testing.T, dir string, files []string, srcPath string) {
for _, f := range files {
installProg(t, filepath.Join(dir, f), srcPath)
}
}
func (test lookPathTest) run(t *testing.T, tmpdir, printpathExe string) {
test.rootDir = tmpdir
createFiles(t, test.rootDir, test.files, printpathExe)
env := createEnv(test.rootDir, test.PATH, test.PATHEXT)
// Run "cmd.exe /c test.searchFor" with new environment and
// work directory set. All candidates are copies of printpath.exe.
// These will output their program paths when run.
should, errCmd := test.runProg(t, env, testenv.Command(t, "cmd", "/c", test.searchFor))
// Run the lookpath program with new environment and work directory set.
have, errLP := test.runProg(t, env, helperCommand(t, "lookpath", test.searchFor))
// Compare results.
if errCmd == nil && errLP == nil {
// both succeeded
if should != have {
t.Fatalf("test=%+v:\ncmd /c ran: %s\nlookpath found: %s", test, should, have)
}
return
}
if errCmd != nil && errLP != nil {
// both failed -> continue
return
}
if errCmd != nil {
t.Fatal(errCmd)
}
if errLP != nil {
t.Fatal(errLP)
}
want string
wantErr error
}
var lookPathTests = []lookPathTest{
{
PATHEXT: `.COM;.EXE;.BAT`,
PATH: `p1;p2`,
name: "first match",
files: []string{`p1\a.exe`, `p2\a.exe`, `p2\a`},
searchFor: `a`,
want: `p1\a.exe`,
},
{
PATHEXT: `.COM;.EXE;.BAT`,
PATH: `p1.dir;p2.dir`,
name: "dirs with extensions",
files: []string{`p1.dir\a`, `p2.dir\a.exe`},
searchFor: `a`,
want: `p2.dir\a.exe`,
},
{
PATHEXT: `.COM;.EXE;.BAT`,
PATH: `p1;p2`,
name: "first with extension",
files: []string{`p1\a.exe`, `p2\a.exe`},
searchFor: `a.exe`,
want: `p1\a.exe`,
},
{
PATHEXT: `.COM;.EXE;.BAT`,
PATH: `p1;p2`,
name: "specific name",
files: []string{`p1\a.exe`, `p2\b.exe`},
searchFor: `b`,
want: `p2\b.exe`,
},
{
PATHEXT: `.COM;.EXE;.BAT`,
PATH: `p1;p2`,
name: "no extension",
files: []string{`p1\b`, `p2\a`},
searchFor: `a`,
fails: true, // TODO(brainman): do not know why this fails
wantErr: exec.ErrNotFound,
},
// If the command name specifies a path, the shell searches
// the specified path for an executable file matching
// the command name. If a match is found, the external
// command (the executable file) executes.
{
PATHEXT: `.COM;.EXE;.BAT`,
PATH: `p1;p2`,
name: "directory, no extension",
files: []string{`p1\a.exe`, `p2\a.exe`},
searchFor: `p2\a`,
want: `p2\a.exe`,
},
// If the command name specifies a path, the shell searches
// the specified path for an executable file matching the command
// name. ... If no match is found, the shell reports an error
// and command processing completes.
{
PATHEXT: `.COM;.EXE;.BAT`,
PATH: `p1;p2`,
files: []string{`p1\b.exe`, `p2\a.exe`},
searchFor: `p2\b`,
fails: true,
},
// If the command name does not specify a path, the shell
// searches the current directory for an executable file
// matching the command name. If a match is found, the external
// command (the executable file) executes.
{
PATHEXT: `.COM;.EXE;.BAT`,
PATH: `p1;p2`,
files: []string{`a`, `p1\a.exe`, `p2\a.exe`},
searchFor: `a`,
},
// The shell now searches each directory specified by the
// PATH environment variable, in the order listed, for an
// executable file matching the command name. If a match
// is found, the external command (the executable file) executes.
{
PATHEXT: `.COM;.EXE;.BAT`,
PATH: `p1;p2`,
files: []string{`p1\a.exe`, `p2\a.exe`},
searchFor: `a`,
},
// The shell now searches each directory specified by the
// PATH environment variable, in the order listed, for an
// executable file matching the command name. If no match
// is found, the shell reports an error and command processing
// completes.
{
PATHEXT: `.COM;.EXE;.BAT`,
PATH: `p1;p2`,
name: "no match",
files: []string{`p1\a.exe`, `p2\a.exe`},
searchFor: `b`,
fails: true,
},
// If the command name includes a file extension, the shell
// searches each directory for the exact file name specified
// by the command name.
{
PATHEXT: `.COM;.EXE;.BAT`,
PATH: `p1;p2`,
files: []string{`p1\a.exe`, `p2\a.exe`},
searchFor: `a.exe`,
wantErr: exec.ErrNotFound,
},
{
PATHEXT: `.COM;.EXE;.BAT`,
PATH: `p1;p2`,
name: "no match with dir",
files: []string{`p1\b.exe`, `p2\a.exe`},
searchFor: `p2\b`,
wantErr: fs.ErrNotExist,
},
{
name: "extensionless file in CWD ignored",
files: []string{`a`, `p1\a.exe`, `p2\a.exe`},
searchFor: `a`,
want: `p1\a.exe`,
},
{
name: "extensionless file in PATH ignored",
files: []string{`p1\a`, `p2\a.exe`},
searchFor: `a`,
want: `p2\a.exe`,
},
{
name: "specific extension",
files: []string{`p1\a.exe`, `p2\a.bat`},
searchFor: `a.bat`,
want: `p2\a.bat`,
},
{
name: "mismatched extension",
files: []string{`p1\a.exe`, `p2\a.exe`},
searchFor: `a.com`,
fails: true, // includes extension and not exact file name match
wantErr: exec.ErrNotFound,
},
{
PATHEXT: `.COM;.EXE;.BAT`,
PATH: `p1`,
name: "doubled extension",
files: []string{`p1\a.exe.exe`},
searchFor: `a.exe`,
want: `p1\a.exe.exe`,
},
{
name: "extension not in PATHEXT",
PATHEXT: `.COM;.BAT`,
PATH: `p1;p2`,
files: []string{`p1\a.exe`, `p2\a.exe`},
searchFor: `a.exe`,
want: `p1\a.exe`,
},
// If the command name does not include a file extension, the shell
// adds the extensions listed in the PATHEXT environment variable,
// one by one, and searches the directory for that file name. Note
// that the shell tries all possible file extensions in a specific
// directory before moving on to search the next directory
// (if there is one).
{
name: "first allowed by PATHEXT",
PATHEXT: `.COM;.EXE`,
PATH: `p1;p2`,
files: []string{`p1\a.bat`, `p2\a.exe`},
searchFor: `a`,
want: `p2\a.exe`,
},
{
name: "first directory containing a PATHEXT match",
PATHEXT: `.COM;.EXE;.BAT`,
PATH: `p1;p2`,
files: []string{`p1\a.bat`, `p2\a.exe`},
searchFor: `a`,
want: `p1\a.bat`,
},
{
name: "first PATHEXT entry",
PATHEXT: `.COM;.EXE;.BAT`,
PATH: `p1;p2`,
files: []string{`p1\a.bat`, `p1\a.exe`, `p2\a.bat`, `p2\a.exe`},
searchFor: `a`,
want: `p1\a.exe`,
},
{
PATHEXT: `.COM`,
PATH: `p1;p2`,
files: []string{`p1\a.bat`, `p2\a.exe`},
name: "ignore dir with PATHEXT extension",
files: []string{`a.exe\`},
searchFor: `a`,
fails: true, // tried all extensions in PATHEXT, but none matches
wantErr: exec.ErrNotFound,
},
}
func TestLookPathWindows(t *testing.T) {
if testing.Short() {
maySkipHelperCommand("lookpath")
t.Skipf("skipping test in short mode that would build a helper binary")
// Not parallel: uses Chdir and Setenv.
// We are using the "printpath" command mode to test exec.Command here,
// so we won't be calling helperCommand to resolve it.
// That may cause it to appear to be unused.
maySkipHelperCommand("printpath")
// Before we begin, find the absolute path to cmd.exe.
// In non-short mode, we will use it to check the ground truth
// of the test's "want" field.
cmdExe, err := exec.LookPath("cmd")
if err != nil {
t.Fatal(err)
}
t.Parallel()
tmp := t.TempDir()
printpathExe := buildPrintPathExe(t, tmp)
// Run all tests.
for i, test := range lookPathTests {
i, test := i, test
t.Run(fmt.Sprint(i), func(t *testing.T) {
t.Parallel()
dir := filepath.Join(tmp, "d"+strconv.Itoa(i))
err := os.Mkdir(dir, 0700)
if err != nil {
t.Fatal("Mkdir failed: ", err)
for _, tt := range lookPathTests {
t.Run(tt.name, func(t *testing.T) {
if tt.want == "" && tt.wantErr == nil {
t.Fatalf("test must specify either want or wantErr")
}
root := t.TempDir()
installProgs(t, root, tt.files)
if tt.PATHEXT != "" {
t.Setenv("PATHEXT", tt.PATHEXT)
t.Logf("set PATHEXT=%s", tt.PATHEXT)
}
var pathVar string
{
paths := make([]string, 0, len(tt.files))
for _, f := range tt.files {
dir := filepath.Join(root, filepath.Dir(f))
if !slices.Contains(paths, dir) {
paths = append(paths, dir)
}
}
pathVar = strings.Join(paths, string(os.PathListSeparator))
}
t.Setenv("PATH", pathVar)
t.Logf("set PATH=%s", pathVar)
chdir(t, root)
if !testing.Short() {
// Check that cmd.exe, which is our source of ground truth,
// agrees that our test case is correct.
cmd := testenv.Command(t, cmdExe, "/c", tt.searchFor, "printpath")
out, err := cmd.Output()
if err == nil {
gotAbs := strings.TrimSpace(string(out))
wantAbs := ""
if tt.want != "" {
wantAbs = filepath.Join(root, tt.want)
}
if gotAbs != wantAbs {
// cmd.exe disagrees. Probably the test case is wrong?
t.Fatalf("%v\n\tresolved to %s\n\twant %s", cmd, gotAbs, wantAbs)
}
} else if tt.wantErr == nil {
if ee, ok := err.(*exec.ExitError); ok && len(ee.Stderr) > 0 {
t.Fatalf("%v: %v\n%s", cmd, err, ee.Stderr)
}
t.Fatalf("%v: %v", cmd, err)
}
}
got, err := exec.LookPath(tt.searchFor)
if filepath.IsAbs(got) {
got, err = filepath.Rel(root, got)
if err != nil {
t.Fatal(err)
}
}
if got != tt.want {
t.Errorf("LookPath(%#q) = %#q; want %#q", tt.searchFor, got, tt.want)
}
if !errors.Is(err, tt.wantErr) {
t.Errorf("LookPath(%#q): %v; want %v", tt.searchFor, err, tt.wantErr)
}
test.run(t, dir, printpathExe)
})
}
}
type commandTest struct {
PATH string
files []string
dir string
arg0 string
want string
fails bool // test is expected to fail
}
func (test commandTest) isSuccess(rootDir, output string, err error) error {
if err != nil {
return fmt.Errorf("test=%+v: exec: %v %v", test, err, output)
}
path := output
if path[:len(rootDir)] != rootDir {
return fmt.Errorf("test=%+v: %q must have %q prefix", test, path, rootDir)
}
path = path[len(rootDir)+1:]
if path != test.want {
return fmt.Errorf("test=%+v: want %q, got %q", test, test.want, path)
}
return nil
}
func (test commandTest) runOne(t *testing.T, rootDir string, env []string, dir, arg0 string) {
cmd := helperCommand(t, "exec", dir, arg0)
cmd.Dir = rootDir
cmd.Env = env
output, err := cmd.CombinedOutput()
err = test.isSuccess(rootDir, string(output), err)
if (err != nil) != test.fails {
if test.fails {
t.Errorf("test=%+v: succeeded, but expected to fail", test)
} else {
t.Error(err)
}
}
}
func (test commandTest) run(t *testing.T, rootDir, printpathExe string) {
createFiles(t, rootDir, test.files, printpathExe)
PATHEXT := `.COM;.EXE;.BAT`
env := createEnv(rootDir, test.PATH, PATHEXT)
test.runOne(t, rootDir, env, test.dir, test.arg0)
name string
PATH []string
files []string
dir string
arg0 string
want string
wantPath string // the resolved c.Path, if different from want
wantErrDot bool
wantRunErr error
}
var commandTests = []commandTest{
// testing commands with no slash, like `a.exe`
{
// should find a.exe in current directory
files: []string{`a.exe`},
arg0: `a.exe`,
want: `a.exe`,
name: "current directory",
files: []string{`a.exe`},
PATH: []string{"."},
arg0: `a.exe`,
want: `a.exe`,
wantErrDot: true,
},
{
// like above, but add PATH in attempt to break the test
PATH: `p2;p`,
files: []string{`a.exe`, `p\a.exe`, `p2\a.exe`},
arg0: `a.exe`,
want: `a.exe`,
name: "with extra PATH",
files: []string{`a.exe`, `p\a.exe`, `p2\a.exe`},
PATH: []string{".", "p2", "p"},
arg0: `a.exe`,
want: `a.exe`,
wantErrDot: true,
},
{
// like above, but use "a" instead of "a.exe" for command
PATH: `p2;p`,
files: []string{`a.exe`, `p\a.exe`, `p2\a.exe`},
arg0: `a`,
want: `a.exe`,
name: "with extra PATH and no extension",
files: []string{`a.exe`, `p\a.exe`, `p2\a.exe`},
PATH: []string{".", "p2", "p"},
arg0: `a`,
want: `a.exe`,
wantErrDot: true,
},
// testing commands with slash, like `.\a.exe`
{
// should find p\a.exe
name: "with dir",
files: []string{`p\a.exe`},
PATH: []string{"."},
arg0: `p\a.exe`,
want: `p\a.exe`,
},
{
// like above, but adding `.` in front of executable should still be OK
name: "with explicit dot",
files: []string{`p\a.exe`},
PATH: []string{"."},
arg0: `.\p\a.exe`,
want: `p\a.exe`,
},
{
// like above, but with PATH added in attempt to break it
PATH: `p2`,
name: "with irrelevant PATH",
files: []string{`p\a.exe`, `p2\a.exe`},
PATH: []string{".", "p2"},
arg0: `p\a.exe`,
want: `p\a.exe`,
},
{
// like above, but make sure .exe is tried even for commands with slash
PATH: `p2`,
name: "with slash and no extension",
files: []string{`p\a.exe`, `p2\a.exe`},
PATH: []string{".", "p2"},
arg0: `p\a`,
want: `p\a.exe`,
},
// tests commands, like `a.exe`, with c.Dir set
{
// should not find a.exe in p, because LookPath(`a.exe`) will fail
files: []string{`p\a.exe`},
dir: `p`,
arg0: `a.exe`,
want: `p\a.exe`,
fails: true,
// should not find a.exe in p, because LookPath(`a.exe`) will fail when
// called by Command (before Dir is set), and that error is sticky.
name: "not found before Dir",
files: []string{`p\a.exe`},
PATH: []string{"."},
dir: `p`,
arg0: `a.exe`,
want: `p\a.exe`,
wantRunErr: exec.ErrNotFound,
},
{
// LookPath(`a.exe`) will find `.\a.exe`, but prefixing that with
// LookPath(`a.exe`) will resolve to `.\a.exe`, but prefixing that with
// dir `p\a.exe` will refer to a non-existent file
files: []string{`a.exe`, `p\not_important_file`},
dir: `p`,
arg0: `a.exe`,
want: `a.exe`,
fails: true,
name: "resolved before Dir",
files: []string{`a.exe`, `p\not_important_file`},
PATH: []string{"."},
dir: `p`,
arg0: `a.exe`,
want: `a.exe`,
wantErrDot: true,
wantRunErr: fs.ErrNotExist,
},
{
// like above, but making test succeed by installing file
// in referred destination (so LookPath(`a.exe`) will still
// find `.\a.exe`, but we successfully execute `p\a.exe`)
files: []string{`a.exe`, `p\a.exe`},
dir: `p`,
arg0: `a.exe`,
want: `p\a.exe`,
name: "relative to Dir",
files: []string{`a.exe`, `p\a.exe`},
PATH: []string{"."},
dir: `p`,
arg0: `a.exe`,
want: `p\a.exe`,
wantErrDot: true,
},
{
// like above, but add PATH in attempt to break the test
PATH: `p2;p`,
files: []string{`a.exe`, `p\a.exe`, `p2\a.exe`},
dir: `p`,
arg0: `a.exe`,
want: `p\a.exe`,
name: "relative to Dir with extra PATH",
files: []string{`a.exe`, `p\a.exe`, `p2\a.exe`},
PATH: []string{".", "p2", "p"},
dir: `p`,
arg0: `a.exe`,
want: `p\a.exe`,
wantErrDot: true,
},
{
// like above, but use "a" instead of "a.exe" for command
PATH: `p2;p`,
files: []string{`a.exe`, `p\a.exe`, `p2\a.exe`},
dir: `p`,
arg0: `a`,
want: `p\a.exe`,
name: "relative to Dir with extra PATH and no extension",
files: []string{`a.exe`, `p\a.exe`, `p2\a.exe`},
PATH: []string{".", "p2", "p"},
dir: `p`,
arg0: `a`,
want: `p\a.exe`,
wantErrDot: true,
},
{
// finds `a.exe` in the PATH regardless of dir set
// because LookPath returns full path in that case
PATH: `p2;p`,
// finds `a.exe` in the PATH regardless of Dir because Command resolves the
// full path (using LookPath) before Dir is set.
name: "from PATH with no match in Dir",
files: []string{`p\a.exe`, `p2\a.exe`},
PATH: []string{".", "p2", "p"},
dir: `p`,
arg0: `a.exe`,
want: `p2\a.exe`,
@ -509,104 +448,127 @@ var commandTests = []commandTest{
// tests commands, like `.\a.exe`, with c.Dir set
{
// should use dir when command is path, like ".\a.exe"
name: "relative to Dir with explicit dot",
files: []string{`p\a.exe`},
PATH: []string{"."},
dir: `p`,
arg0: `.\a.exe`,
want: `p\a.exe`,
},
{
// like above, but with PATH added in attempt to break it
PATH: `p2`,
name: "relative to Dir with dot and extra PATH",
files: []string{`p\a.exe`, `p2\a.exe`},
PATH: []string{".", "p2"},
dir: `p`,
arg0: `.\a.exe`,
want: `p\a.exe`,
},
{
// like above, but make sure .exe is tried even for commands with slash
PATH: `p2`,
// LookPath(".\a") will fail before Dir is set, and that error is sticky.
name: "relative to Dir with dot and extra PATH and no extension",
files: []string{`p\a.exe`, `p2\a.exe`},
PATH: []string{".", "p2"},
dir: `p`,
arg0: `.\a`,
want: `p\a.exe`,
},
{
// LookPath(".\a") will fail before Dir is set, and that error is sticky.
name: "relative to Dir with different extension",
files: []string{`a.exe`, `p\a.bat`},
PATH: []string{"."},
dir: `p`,
arg0: `.\a`,
want: `p\a.bat`,
},
}
func TestCommand(t *testing.T) {
if testing.Short() {
maySkipHelperCommand("exec")
t.Skipf("skipping test in short mode that would build a helper binary")
}
t.Parallel()
// Not parallel: uses Chdir and Setenv.
tmp := t.TempDir()
printpathExe := buildPrintPathExe(t, tmp)
// We are using the "printpath" command mode to test exec.Command here,
// so we won't be calling helperCommand to resolve it.
// That may cause it to appear to be unused.
maySkipHelperCommand("printpath")
// Run all tests.
for i, test := range commandTests {
i, test := i, test
t.Run(fmt.Sprint(i), func(t *testing.T) {
t.Parallel()
dir := filepath.Join(tmp, "d"+strconv.Itoa(i))
err := os.Mkdir(dir, 0700)
if err != nil {
t.Fatal("Mkdir failed: ", err)
for _, tt := range commandTests {
t.Run(tt.name, func(t *testing.T) {
if tt.PATH == nil {
t.Fatalf("test must specify PATH")
}
root := t.TempDir()
installProgs(t, root, tt.files)
paths := make([]string, 0, len(tt.PATH))
for _, p := range tt.PATH {
if p == "." {
paths = append(paths, ".")
} else {
paths = append(paths, filepath.Join(root, p))
}
}
pathVar := strings.Join(paths, string(os.PathListSeparator))
t.Setenv("PATH", pathVar)
t.Logf("set PATH=%s", pathVar)
chdir(t, root)
cmd := exec.Command(tt.arg0, "printpath")
cmd.Dir = filepath.Join(root, tt.dir)
if tt.wantErrDot {
if errors.Is(cmd.Err, exec.ErrDot) {
cmd.Err = nil
} else {
t.Fatalf("cmd.Err = %v; want ErrDot", cmd.Err)
}
}
out, err := cmd.Output()
if err != nil {
if ee, ok := err.(*exec.ExitError); ok && len(ee.Stderr) > 0 {
t.Logf("%v: %v\n%s", cmd, err, ee.Stderr)
} else {
t.Logf("%v: %v", cmd, err)
}
if !errors.Is(err, tt.wantRunErr) {
t.Errorf("want %v", tt.wantRunErr)
}
return
}
got := strings.TrimSpace(string(out))
if filepath.IsAbs(got) {
got, err = filepath.Rel(root, got)
if err != nil {
t.Fatal(err)
}
}
if got != tt.want {
t.Errorf("\nran %#q\nwant %#q", got, tt.want)
}
gotPath := cmd.Path
wantPath := tt.wantPath
if wantPath == "" {
if strings.Contains(tt.arg0, `\`) {
wantPath = tt.arg0
if filepath.Ext(wantPath) == "" {
wantPath += filepath.Ext(tt.want)
}
} else if tt.wantErrDot {
wantPath = strings.TrimPrefix(tt.want, tt.dir+`\`)
if filepath.Base(wantPath) == wantPath {
wantPath = `.\` + wantPath
}
} else {
wantPath = filepath.Join(root, tt.want)
}
}
if gotPath != wantPath {
t.Errorf("\ncmd.Path = %#q\nwant %#q", gotPath, wantPath)
}
test.run(t, dir, printpathExe)
})
}
}
// buildPrintPathExe creates a Go program that prints its own path.
// dir is a temp directory where executable will be created.
// The function returns full path to the created program.
func buildPrintPathExe(t *testing.T, dir string) string {
const name = "printpath"
srcname := name + ".go"
err := os.WriteFile(filepath.Join(dir, srcname), []byte(printpathSrc), 0644)
if err != nil {
t.Fatalf("failed to create source: %v", err)
}
if err != nil {
t.Fatalf("failed to execute template: %v", err)
}
outname := name + ".exe"
cmd := testenv.Command(t, testenv.GoToolPath(t), "build", "-o", outname, srcname)
cmd.Dir = dir
out, err := cmd.CombinedOutput()
if err != nil {
t.Fatalf("failed to build executable: %v - %v", err, string(out))
}
return filepath.Join(dir, outname)
}
const printpathSrc = `
package main
import (
"os"
"syscall"
"unsafe"
)
func getMyName() (string, error) {
var sysproc = syscall.MustLoadDLL("kernel32.dll").MustFindProc("GetModuleFileNameW")
b := make([]uint16, syscall.MAX_PATH)
r, _, err := sysproc.Call(0, uintptr(unsafe.Pointer(&b[0])), uintptr(len(b)))
n := uint32(r)
if n == 0 {
return "", err
}
return syscall.UTF16ToString(b[0:n]), nil
}
func main() {
path, err := getMyName()
if err != nil {
os.Stderr.Write([]byte("getMyName failed: " + err.Error() + "\n"))
os.Exit(1)
}
os.Stdout.Write([]byte(path))
}
`