From: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Date: Sat, 13 Aug 2022 17:35:24 +0000 (+0700)
Subject: internal/singleflight: make DoChan only return Result channel
X-Git-Tag: go1.20rc1~1435
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=75cdd2c75dfa3f8095f9e9304513445d461580d4;p=gostls13.git

internal/singleflight: make DoChan only return Result channel

So next CL can delete "internal/singleflight" and vendor
"golang.org/x/sync/singleflight" instead.

For #31697

Change-Id: I020da1e5a48d484637b538c010029218f5a4a744
Reviewed-on: https://go-review.googlesource.com/c/go/+/423655
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Bryan Mills <bcmills@google.com>
Reviewed-by: David Chase <drchase@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
---

diff --git a/src/internal/singleflight/singleflight.go b/src/internal/singleflight/singleflight.go
index 07b3f40ec0..19d5a94a0b 100644
--- a/src/internal/singleflight/singleflight.go
+++ b/src/internal/singleflight/singleflight.go
@@ -65,10 +65,8 @@ func (g *Group) Do(key string, fn func() (any, error)) (v any, err error, shared
 }
 
 // DoChan is like Do but returns a channel that will receive the
-// results when they are ready. The second result is true if the function
-// will eventually be called, false if it will not (because there is
-// a pending request with this key).
-func (g *Group) DoChan(key string, fn func() (any, error)) (<-chan Result, bool) {
+// results when they are ready.
+func (g *Group) DoChan(key string, fn func() (any, error)) <-chan Result {
 	ch := make(chan Result, 1)
 	g.mu.Lock()
 	if g.m == nil {
@@ -78,7 +76,7 @@ func (g *Group) DoChan(key string, fn func() (any, error)) (<-chan Result, bool)
 		c.dups++
 		c.chans = append(c.chans, ch)
 		g.mu.Unlock()
-		return ch, false
+		return ch
 	}
 	c := &call{chans: []chan<- Result{ch}}
 	c.wg.Add(1)
@@ -87,7 +85,7 @@ func (g *Group) DoChan(key string, fn func() (any, error)) (<-chan Result, bool)
 
 	go g.doCall(c, key, fn)
 
-	return ch, true
+	return ch
 }
 
 // doCall handles the single call for a key.
diff --git a/src/net/lookup.go b/src/net/lookup.go
index 3cc53f1db6..b283c67945 100644
--- a/src/net/lookup.go
+++ b/src/net/lookup.go
@@ -316,7 +316,7 @@ func (r *Resolver) lookupIPAddr(ctx context.Context, network, host string) ([]IP
 
 	lookupKey := network + "\000" + host
 	dnsWaitGroup.Add(1)
-	ch, _ := r.getLookupGroup().DoChan(lookupKey, func() (any, error) {
+	ch := r.getLookupGroup().DoChan(lookupKey, func() (any, error) {
 		return testHookLookupIP(lookupGroupCtx, resolverFunc, network, host)
 	})