encoding/json: make use of Buffer.AvailableBuffer

Use the explicit API for acquiring an empty available buffer,
rather than the hack that's implemented in terms of Bytes and Len.

Change-Id: If286ed42693acd61ffe28dc849ed4b76c3ae4434
Reviewed-on: https://go-review.googlesource.com/c/go/+/476337
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Auto-Submit: Joseph Tsai <joetsai@digital-static.net>
Run-TryBot: Joseph Tsai <joetsai@digital-static.net>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@google.com>

1 files changed, 2 insertions, 6 deletions

diff --git a/src/encoding/json/encode.go b/src/encoding/json/encode.go
index f3c824d13e..79a82cfe75 100644
--- a/src/encoding/json/encode.go
+++ b/src/encoding/json/encode.go
@@ -259,10 +259,6 @@ type encodeState struct {
 	ptrSeen  map[any]struct{}
 }
 
-func (e *encodeState) AvailableBuffer() []byte {
-	return availableBuffer(&e.Buffer)
-}
-
 const startDetectingCyclesAfter = 1000
 
 var encodeStatePool sync.Pool
@@ -445,7 +441,7 @@ func marshalerEncoder(e *encodeState, v reflect.Value, opts encOpts) {
 	b, err := m.MarshalJSON()
 	if err == nil {
 		e.Grow(len(b))
-		out := availableBuffer(&e.Buffer)
+		out := e.AvailableBuffer()
 		out, err = appendCompact(out, b, opts.escapeHTML)
 		e.Buffer.Write(out)
 	}
@@ -464,7 +460,7 @@ func addrMarshalerEncoder(e *encodeState, v reflect.Value, opts encOpts) {
 	b, err := m.MarshalJSON()
 	if err == nil {
 		e.Grow(len(b))
-		out := availableBuffer(&e.Buffer)
+		out := e.AvailableBuffer()
 		out, err = appendCompact(out, b, opts.escapeHTML)
 		e.Buffer.Write(out)
 	}