testing: add TB.TempDir

Fixes #35998

Change-Id: I87c6bf4e34e832be68862ca16ecfa6ea12048d31
Reviewed-on: https://go-review.googlesource.com/c/go/+/226877
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

diff --git a/src/go/build/deps_test.go b/src/go/build/deps_test.go
index 9ef85dbf1bab9b282d1ad09ca66b679277ea9895..91ecae836a0976d2ad493e6adcc6a760ef7e9f90 100644 (file)
--- a/src/go/build/deps_test.go
+++ b/src/go/build/deps_test.go
@@ -199,7 +199,7 @@ var pkgDeps = map[string][]string{
        "runtime/trace":  {"L0", "context", "fmt"},
        "text/tabwriter": {"L2"},
 
-       "testing":                  {"L2", "flag", "fmt", "internal/race", "os", "runtime/debug", "runtime/pprof", "runtime/trace", "time"},
+       "testing":                  {"L2", "flag", "fmt", "internal/race", "io/ioutil", "os", "runtime/debug", "runtime/pprof", "runtime/trace", "time"},
        "testing/iotest":           {"L2", "log"},
        "testing/quick":            {"L2", "flag", "fmt", "reflect", "time"},
        "internal/obscuretestdata": {"L2", "OS", "encoding/base64"},

diff --git a/src/io/ioutil/export_test.go b/src/io/ioutil/export_test.go
new file mode 100644 (file)
index 0000000..dff55f0
--- /dev/null
+++ b/src/io/ioutil/export_test.go
@@ -0,0 +1,7 @@
+// Copyright 2020 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 ioutil
+
+var ErrPatternHasSeparator = errPatternHasSeparator

diff --git a/src/io/ioutil/ioutil_test.go b/src/io/ioutil/ioutil_test.go
index ef3c6d7975eeb21ccdf50390cc4e7d381f726258..db85755bdbad882f07fa36527fe639aafd9d08b5 100644 (file)
--- a/src/io/ioutil/ioutil_test.go
+++ b/src/io/ioutil/ioutil_test.go
@@ -2,10 +2,11 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package ioutil
+package ioutil_test
 
 import (
        "bytes"
+       . "io/ioutil"
        "os"
        "path/filepath"
        "testing"

diff --git a/src/io/ioutil/tempfile_test.go b/src/io/ioutil/tempfile_test.go
index 469d2c98b3dbdeefb65e444a2f999adf2c39e167..fcc5101fcc8cdc112a41f028aba144f22462fde4 100644 (file)
--- a/src/io/ioutil/tempfile_test.go
+++ b/src/io/ioutil/tempfile_test.go
@@ -2,9 +2,10 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package ioutil
+package ioutil_test
 
 import (
+       . "io/ioutil"
        "os"
        "path/filepath"
        "regexp"
@@ -59,7 +60,7 @@ func TestTempFile_BadPattern(t *testing.T) {
        tests := []struct {
                pattern string
                wantErr bool
-       } {
+       }{
                {"ioutil*test", false},
                {"ioutil_test*foo", false},
                {"ioutil_test" + sep + "foo", true},
@@ -80,7 +81,7 @@ func TestTempFile_BadPattern(t *testing.T) {
                                if err == nil {
                                        t.Errorf("Expected an error for pattern %q", tt.pattern)
                                }
-                               if g, w := err, errPatternHasSeparator; g != w {
+                               if g, w := err, ErrPatternHasSeparator; g != w {
                                        t.Errorf("Error mismatch: got %#v, want %#v for pattern %q", g, w, tt.pattern)
                                }
                        } else if err != nil {
@@ -166,7 +167,7 @@ func TestTempDir_BadPattern(t *testing.T) {
        tests := []struct {
                pattern string
                wantErr bool
-       } {
+       }{
                {"ioutil*test", false},
                {"ioutil_test*foo", false},
                {"ioutil_test" + sep + "foo", true},
@@ -182,7 +183,7 @@ func TestTempDir_BadPattern(t *testing.T) {
                                if err == nil {
                                        t.Errorf("Expected an error for pattern %q", tt.pattern)
                                }
-                               if g, w := err, errPatternHasSeparator; g != w {
+                               if g, w := err, ErrPatternHasSeparator; g != w {
                                        t.Errorf("Error mismatch: got %#v, want %#v for pattern %q", g, w, tt.pattern)
                                }
                        } else if err != nil {

diff --git a/src/testing/testing.go b/src/testing/testing.go
index 85a92c93848d67a6c06644cd7d82d6a92b90635e..d546f56478c4d759d2dd1f98736a9d46ab470b53 100644 (file)
--- a/src/testing/testing.go
+++ b/src/testing/testing.go
@@ -239,6 +239,7 @@ import (
        "fmt"
        "internal/race"
        "io"
+       "io/ioutil"
        "os"
        "runtime"
        "runtime/debug"
@@ -362,6 +363,10 @@ type common struct {
        barrier  chan bool // To signal parallel subtests they may start.
        signal   chan bool // To signal a test is done.
        sub      []*T      // Queue of subtests to be run in parallel.
+
+       tempDirOnce sync.Once
+       tempDir     string
+       tempDirErr  error
 }
 
 // Short reports whether the -test.short flag is set.
@@ -561,6 +566,7 @@ type TB interface {
        SkipNow()
        Skipf(format string, args ...interface{})
        Skipped() bool
+       TempDir() string
 
        // A private method to prevent users implementing the
        // interface and so future additions to it will not
@@ -791,6 +797,30 @@ func (c *common) Cleanup(f func()) {
        }
 }
 
+// TempDir returns a temporary directory for the test to use.
+// It is lazily created on first access, and calls t.Fatal if the directory
+// creation fails.
+// Subsequent calls to t.TempDir return the same directory.
+// The directory is automatically removed by Cleanup when the test and
+// all its subtests complete.
+func (c *common) TempDir() string {
+       c.tempDirOnce.Do(func() {
+               c.Helper()
+               c.tempDir, c.tempDirErr = ioutil.TempDir("", c.Name())
+               if c.tempDirErr == nil {
+                       c.Cleanup(func() {
+                               if err := os.RemoveAll(c.tempDir); err != nil {
+                                       c.Errorf("TempDir RemoveAll cleanup: %v", err)
+                               }
+                       })
+               }
+       })
+       if c.tempDirErr != nil {
+               c.Fatalf("TempDir: %v", c.tempDirErr)
+       }
+       return c.tempDir
+}
+
 // panicHanding is an argument to runCleanup.
 type panicHandling int
 

diff --git a/src/testing/testing_test.go b/src/testing/testing_test.go
index 45e44683b43c017cfb4512a5d8b81e19308b9d80..afb35a96d4522e000bfbea46335f17fbb9c29147 100644 (file)
--- a/src/testing/testing_test.go
+++ b/src/testing/testing_test.go
@@ -5,6 +5,7 @@
 package testing_test
 
 import (
+       "io/ioutil"
        "os"
        "testing"
 )
@@ -16,3 +17,50 @@ import (
 func TestMain(m *testing.M) {
        os.Exit(m.Run())
 }
+
+func TestTempDir(t *testing.T) {
+       dirCh := make(chan string, 1)
+       t.Cleanup(func() {
+               // Verify directory has been removed.
+               select {
+               case dir := <-dirCh:
+                       fi, err := os.Stat(dir)
+                       if os.IsNotExist(err) {
+                               // All good
+                               return
+                       }
+                       if err != nil {
+                               t.Fatal(err)
+                       }
+                       t.Errorf("directory %q stil exists: %v, isDir=%v", dir, fi, fi.IsDir())
+               default:
+                       if !t.Failed() {
+                               t.Fatal("never received dir channel")
+                       }
+               }
+       })
+
+       dir := t.TempDir()
+       if dir == "" {
+               t.Fatal("expected dir")
+       }
+       dir2 := t.TempDir()
+       if dir != dir2 {
+               t.Fatal("directory changed between calls")
+       }
+       dirCh <- dir
+       fi, err := os.Stat(dir)
+       if err != nil {
+               t.Fatal(err)
+       }
+       if !fi.IsDir() {
+               t.Errorf("dir %q is not a dir", dir)
+       }
+       fis, err := ioutil.ReadDir(dir)
+       if err != nil {
+               t.Fatal(err)
+       }
+       if len(fis) > 0 {
+               t.Errorf("unexpected %d files in TempDir: %v", len(fis), fis)
+       }
+}