io: check n in testReadAtLeast

Change-Id: I53859d4d3c729cce9f73b14dc2dd8571f7e7ffb3
Reviewed-on: https://go-review.googlesource.com/c/go/+/216457
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Robert Griesemer <gri@golang.org>

diff --git a/src/io/io_test.go b/src/io/io_test.go
index ca90403c59c66b848bef83e7c8ff09ccf175e77e..170513dcc0d5921b08c120d7ee6c2352332de298 100644 (file)
--- a/src/io/io_test.go
+++ b/src/io/io_test.go
@@ -285,6 +285,9 @@ func testReadAtLeast(t *testing.T, rb ReadWriter) {
        if err != nil {
                t.Error(err)
        }
+       if n != 2 {
+               t.Errorf("expected to have read 2 bytes, got %v", n)
+       }
        n, err = ReadAtLeast(rb, buf, 4)
        if err != ErrShortBuffer {
                t.Errorf("expected ErrShortBuffer got %v", err)