io/ioutil, old/template: do not assume _test exists for scratch space

R=golang-dev, r
CC=golang-dev
https://golang.org/cl/5496052

src/pkg/io/ioutil/ioutil_test.go

@@ -37,7 +37,11 @@ func TestReadFile(t *testing.T) {
 }
 
 func TestWriteFile(t *testing.T) {
-	filename := "_test/rumpelstilzchen"
+	f, err := TempFile("", "ioutil-test")
+	if err != nil {
+		t.Fatal(err)
+	}
+	filename := f.Name()
 	data := "Programming today is a race between software engineers striving to " +
 		"build bigger and better idiot-proof programs, and the Universe trying " +
 		"to produce bigger and better idiots. So far, the Universe is winning."

src/pkg/old/template/template_test.go

@@ -10,6 +10,7 @@ import (
 	"fmt"
 	"io"
 	"io/ioutil"
+	"os"
 	"strings"
 	"testing"
 )
@@ -463,23 +464,28 @@ func TestAll(t *testing.T) {
 	// Parse
 	testAll(t, func(test *Test) (*Template, error) { return Parse(test.in, formatters) })
 	// ParseFile
+	f, err := ioutil.TempFile("", "template-test")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer os.Remove(f.Name())
 	testAll(t, func(test *Test) (*Template, error) {
-		err := ioutil.WriteFile("_test/test.tmpl", []byte(test.in), 0600)
+		err := ioutil.WriteFile(f.Name(), []byte(test.in), 0600)
 		if err != nil {
 			t.Error("unexpected write error:", err)
 			return nil, err
 		}
-		return ParseFile("_test/test.tmpl", formatters)
+		return ParseFile(f.Name(), formatters)
 	})
 	// tmpl.ParseFile
 	testAll(t, func(test *Test) (*Template, error) {
-		err := ioutil.WriteFile("_test/test.tmpl", []byte(test.in), 0600)
+		err := ioutil.WriteFile(f.Name(), []byte(test.in), 0600)
 		if err != nil {
 			t.Error("unexpected write error:", err)
 			return nil, err
 		}
 		tmpl := New(formatters)
-		return tmpl, tmpl.ParseFile("_test/test.tmpl")
+		return tmpl, tmpl.ParseFile(f.Name())
 	})
 }