1 files changed, 234 insertions, 0 deletions
diff --git a/src/testing/testing_test.go b/src/testing/testing_test.go
new file mode 100644
index 0000000..3616f04
--- /dev/null
+++ b/src/testing/testing_test.go
@@ -0,0 +1,234 @@
+// Copyright 2014 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 testing_test
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+)
+
+// This is exactly what a test would do without a TestMain.
+// It's here only so that there is at least one package in the
+// standard library with a TestMain, so that code is executed.
+
+func TestMain(m *testing.M) {
+	os.Exit(m.Run())
+}
+
+func TestTempDirInCleanup(t *testing.T) {
+	var dir string
+
+	t.Run("test", func(t *testing.T) {
+		t.Cleanup(func() {
+			dir = t.TempDir()
+		})
+		_ = t.TempDir()
+	})
+
+	fi, err := os.Stat(dir)
+	if fi != nil {
+		t.Fatalf("Directory %q from user Cleanup still exists", dir)
+	}
+	if !os.IsNotExist(err) {
+		t.Fatalf("Unexpected error: %v", err)
+	}
+}
+
+func TestTempDirInBenchmark(t *testing.T) {
+	testing.Benchmark(func(b *testing.B) {
+		if !b.Run("test", func(b *testing.B) {
+			// Add a loop so that the test won't fail. See issue 38677.
+			for i := 0; i < b.N; i++ {
+				_ = b.TempDir()
+			}
+		}) {
+			t.Fatal("Sub test failure in a benchmark")
+		}
+	})
+}
+
+func TestTempDir(t *testing.T) {
+	testTempDir(t)
+	t.Run("InSubtest", testTempDir)
+	t.Run("test/subtest", testTempDir)
+	t.Run("test\\subtest", testTempDir)
+	t.Run("test:subtest", testTempDir)
+	t.Run("test/..", testTempDir)
+	t.Run("../test", testTempDir)
+	t.Run("test[]", testTempDir)
+	t.Run("test*", testTempDir)
+	t.Run("äöüéè", testTempDir)
+}
+
+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 still 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("subsequent calls to TempDir returned the same directory")
+	}
+	if filepath.Dir(dir) != filepath.Dir(dir2) {
+		t.Fatalf("calls to TempDir do not share a parent; got %q, %q", dir, dir2)
+	}
+	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)
+	}
+	files, err := os.ReadDir(dir)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(files) > 0 {
+		t.Errorf("unexpected %d files in TempDir: %v", len(files), files)
+	}
+
+	glob := filepath.Join(dir, "*.txt")
+	if _, err := filepath.Glob(glob); err != nil {
+		t.Error(err)
+	}
+}
+
+func TestSetenv(t *testing.T) {
+	tests := []struct {
+		name               string
+		key                string
+		initialValueExists bool
+		initialValue       string
+		newValue           string
+	}{
+		{
+			name:               "initial value exists",
+			key:                "GO_TEST_KEY_1",
+			initialValueExists: true,
+			initialValue:       "111",
+			newValue:           "222",
+		},
+		{
+			name:               "initial value exists but empty",
+			key:                "GO_TEST_KEY_2",
+			initialValueExists: true,
+			initialValue:       "",
+			newValue:           "222",
+		},
+		{
+			name:               "initial value is not exists",
+			key:                "GO_TEST_KEY_3",
+			initialValueExists: false,
+			initialValue:       "",
+			newValue:           "222",
+		},
+	}
+
+	for _, test := range tests {
+		if test.initialValueExists {
+			if err := os.Setenv(test.key, test.initialValue); err != nil {
+				t.Fatalf("unable to set env: got %v", err)
+			}
+		} else {
+			os.Unsetenv(test.key)
+		}
+
+		t.Run(test.name, func(t *testing.T) {
+			t.Setenv(test.key, test.newValue)
+			if os.Getenv(test.key) != test.newValue {
+				t.Fatalf("unexpected value after t.Setenv: got %s, want %s", os.Getenv(test.key), test.newValue)
+			}
+		})
+
+		got, exists := os.LookupEnv(test.key)
+		if got != test.initialValue {
+			t.Fatalf("unexpected value after t.Setenv cleanup: got %s, want %s", got, test.initialValue)
+		}
+		if exists != test.initialValueExists {
+			t.Fatalf("unexpected value after t.Setenv cleanup: got %t, want %t", exists, test.initialValueExists)
+		}
+	}
+}
+
+func TestSetenvWithParallelAfterSetenv(t *testing.T) {
+	defer func() {
+		want := "testing: t.Parallel called after t.Setenv; cannot set environment variables in parallel tests"
+		if got := recover(); got != want {
+			t.Fatalf("expected panic; got %#v want %q", got, want)
+		}
+	}()
+
+	t.Setenv("GO_TEST_KEY_1", "value")
+
+	t.Parallel()
+}
+
+func TestSetenvWithParallelBeforeSetenv(t *testing.T) {
+	defer func() {
+		want := "testing: t.Setenv called after t.Parallel; cannot set environment variables in parallel tests"
+		if got := recover(); got != want {
+			t.Fatalf("expected panic; got %#v want %q", got, want)
+		}
+	}()
+
+	t.Parallel()
+
+	t.Setenv("GO_TEST_KEY_1", "value")
+}
+
+func TestSetenvWithParallelParentBeforeSetenv(t *testing.T) {
+	t.Parallel()
+
+	t.Run("child", func(t *testing.T) {
+		defer func() {
+			want := "testing: t.Setenv called after t.Parallel; cannot set environment variables in parallel tests"
+			if got := recover(); got != want {
+				t.Fatalf("expected panic; got %#v want %q", got, want)
+			}
+		}()
+
+		t.Setenv("GO_TEST_KEY_1", "value")
+	})
+}
+
+func TestSetenvWithParallelGrandParentBeforeSetenv(t *testing.T) {
+	t.Parallel()
+
+	t.Run("child", func(t *testing.T) {
+		t.Run("grand-child", func(t *testing.T) {
+			defer func() {
+				want := "testing: t.Setenv called after t.Parallel; cannot set environment variables in parallel tests"
+				if got := recover(); got != want {
+					t.Fatalf("expected panic; got %#v want %q", got, want)
+				}
+			}()
+
+			t.Setenv("GO_TEST_KEY_1", "value")
+		})
+	})
+}