From: Peter Collingbourne <pcc@google.com>
Date: Wed, 20 Mar 2024 02:27:22 +0000 (-0700)
Subject: sync: name the Map.CompareAndSwap return value
X-Git-Tag: go1.23rc1~817
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=36cd880878a9804489557c29fa768647d665fbe0;p=gostls13.git

sync: name the Map.CompareAndSwap return value

The godoc for sync.Map.CompareAndSwap does not document the meaning
of its return value. Document it by giving it a name.

Change-Id: I50ad9c078a7885f5ce83489d66d138d491c35861
Reviewed-on: https://go-review.googlesource.com/c/go/+/572657
Reviewed-by: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
---

diff --git a/src/sync/map.go b/src/sync/map.go
index 7ae97bce1d..504410bc4b 100644
--- a/src/sync/map.go
+++ b/src/sync/map.go
@@ -393,7 +393,7 @@ func (m *Map) Swap(key, value any) (previous any, loaded bool) {
 // CompareAndSwap swaps the old and new values for key
 // if the value stored in the map is equal to old.
 // The old value must be of a comparable type.
-func (m *Map) CompareAndSwap(key, old, new any) bool {
+func (m *Map) CompareAndSwap(key, old, new any) (swapped bool) {
 	read := m.loadReadOnly()
 	if e, ok := read.m[key]; ok {
 		return e.tryCompareAndSwap(old, new)
@@ -404,7 +404,7 @@ func (m *Map) CompareAndSwap(key, old, new any) bool {
 	m.mu.Lock()
 	defer m.mu.Unlock()
 	read = m.loadReadOnly()
-	swapped := false
+	swapped = false
 	if e, ok := read.m[key]; ok {
 		swapped = e.tryCompareAndSwap(old, new)
 	} else if e, ok := m.dirty[key]; ok {