1 files changed, 12 insertions, 0 deletions
diff --git a/libgo/go/bytes/reader_test.go b/libgo/go/bytes/reader_test.go
index d3dce53499e..b929a282609 100644
--- a/libgo/go/bytes/reader_test.go
+++ b/libgo/go/bytes/reader_test.go
@@ -244,3 +244,15 @@ func TestReaderCopyNothing(t *testing.T) {
 		t.Errorf("behavior differs: with = %#v; without: %#v", with, withOut)
 	}
 }
+
+// tests that Len is affected by reads, but Size is not.
+func TestReaderLenSize(t *testing.T) {
+	r := NewReader([]byte("abc"))
+	io.CopyN(ioutil.Discard, r, 1)
+	if r.Len() != 2 {
+		t.Errorf("Len = %d; want 2", r.Len())
+	}
+	if r.Size() != 3 {
+		t.Errorf("Size = %d; want 3", r.Size())
+	}
+}