bufiox.NewReader on *bufiox.Reader

bufiox/bufio_test.go

@@ -71,6 +71,11 @@ func TestSeeker(t *testing.T) {
 	if err != nil || string(data) != "Hello, china!!!" {
 		t.Fatal("ReadAll failed:", err, data)
 	}
+
+	b3 := NewReaderSize(b2, 32)
+	if b2 != b3 {
+		t.Fatal("NewReader on *bufiox.Reader")
+	}
 }
 
 // -------------------------------------------------------------------------------------

bufiox/seek.go

@@ -12,17 +12,24 @@ type Reader struct {
 	bufio.Reader
 }
 
+const (
+	defaultBufSize = 4096
+)
+
 // NewReader returns a new Reader whose buffer has the default size.
 func NewReader(rd io.ReadSeeker) *Reader {
-	r := bufio.NewReader(rd)
-	return &Reader{Reader: *r}
+	return NewReaderSize(rd, defaultBufSize)
 }
 
 // NewReaderSize returns a new Reader whose buffer has at least the specified
 // size. If the argument io.Reader is already a Reader with large enough size,
 // it returns the underlying Reader.
 //
 func NewReaderSize(rd io.ReadSeeker, size int) *Reader {
+	b, ok := rd.(*Reader)
+	if ok && b.Size() >= size {
+		return b
+	}
 	r := bufio.NewReaderSize(rd, size)
 	return &Reader{Reader: *r}
 }