test: let TLog take a testing.B too. add tests.

Change-Id: I25c47960ef63be85994a133da85072005ca47a85

pkg/test/test.go

@@ -34,9 +34,27 @@ func BrokenTest(t *testing.T) {
 	}
 }
 
+// TB is a copy of Go 1.2's testing.TB.
+type TB interface {
+	Error(args ...interface{})
+	Errorf(format string, args ...interface{})
+	Fail()
+	FailNow()
+	Failed() bool
+	Fatal(args ...interface{})
+	Fatalf(format string, args ...interface{})
+	Log(args ...interface{})
+	Logf(format string, args ...interface{})
+	Skip(args ...interface{})
+	SkipNow()
+	Skipf(format string, args ...interface{})
+	Skipped() bool
+}
+
 // TLog changes the log package's output to log to t and returns a function
 // to reset it back to stderr.
-func TLog(t *testing.T) func() {
+func TLog(t TB) func() {
+	// TODO(bradfitz): once we rely on Go 1.2, change this to take a testing.TB.
 	log.SetOutput(&twriter{t: t})
 	return func() {
 		log.SetOutput(os.Stderr)
@@ -44,7 +62,7 @@ func TLog(t *testing.T) func() {
 }
 
 type twriter struct {
-	t   *testing.T
+	t   TB
 	buf bytes.Buffer
 }
 

pkg/test/test_test.go

@@ -17,8 +17,41 @@ limitations under the License.
 package test_test
 
 import (
+	"log"
+	"reflect"
+	"testing"
+
 	"camlistore.org/pkg/index"
 	. "camlistore.org/pkg/test"
 )
 
 var _ index.Interface = (*FakeIndex)(nil)
+
+type tbLogger struct {
+	TB
+	log []string
+}
+
+func (l *tbLogger) Log(args ...interface{}) {
+	l.log = append(l.log, args[0].(string))
+}
+
+func TestTLog(t *testing.T) {
+	tb := new(tbLogger)
+	defer TLog(tb)()
+	defer log.SetFlags(log.Flags())
+	log.SetFlags(0)
+
+	log.Printf("hello")
+	log.Printf("hello\n")
+	log.Printf("some text\nand more text\n")
+	want := []string{
+		"hello",
+		"hello",
+		"some text",
+		"and more text",
+	}
+	if !reflect.DeepEqual(tb.log, want) {
+		t.Errorf("Got %q; want %q", tb.log, want)
+	}
+}