bufio: use strings.Builder

Change-Id: Ia8d6cea75b32c8839837c1bb1e13cde9b236abdd
Reviewed-on: https://go-review.googlesource.com/c/go/+/435939
Run-TryBot: xie cui <523516579@qq.com>
Reviewed-by: Robert Griesemer <gri@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Auto-Submit: Dmitri Shuralyov <dmitshur@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>

diff --git a/src/bufio/bufio_test.go b/src/bufio/bufio_test.go
index e6a6c23dbf52421a1caba1e804edf304b46a2754..64ccd025ea11a9ff8aaffa633f068a930836eccd 100644 (file)
--- a/src/bufio/bufio_test.go
+++ b/src/bufio/bufio_test.go
@@ -746,7 +746,7 @@ func TestNewWriterSizeIdempotent(t *testing.T) {
 
 func TestWriteString(t *testing.T) {
        const BufSize = 8
-       buf := new(bytes.Buffer)
+       buf := new(strings.Builder)
        b := NewWriterSize(buf, BufSize)
        b.WriteString("0")                         // easy
        b.WriteString("123456")                    // still easy
@@ -757,8 +757,8 @@ func TestWriteString(t *testing.T) {
                t.Error("WriteString", err)
        }
        s := "01234567890abcdefghijklmnopqrstuvwxyz"
-       if string(buf.Bytes()) != s {
-               t.Errorf("WriteString wants %q gets %q", s, string(buf.Bytes()))
+       if buf.String() != s {
+               t.Errorf("WriteString wants %q gets %q", s, buf.String())
        }
 }
 
@@ -1389,7 +1389,7 @@ func TestWriterReadFromUntilEOF(t *testing.T) {
                t.Fatalf("ReadFrom returned (%v, %v), want (4, nil)", n2, err)
        }
        w.Flush()
-       if got, want := string(buf.Bytes()), "0123abcd"; got != want {
+       if got, want := buf.String(), "0123abcd"; got != want {
                t.Fatalf("buf.Bytes() returned %q, want %q", got, want)
        }
 }