サンプル

golang.org/x/sync 0.22.0: Handle singleflight DoChan per-caller buffered channels, unclosed channel semantics, abandoned consumer non-blocking delivery, and sync Do coexistence

検証済みサンプル — golang golang.org/x/sync 0.22.0: Handle singleflight DoChan per-caller buffered channels, unclosed channel semantics, abandoned consumer…

sha256:079d540812c58ea64c9a9a6abc30c8f6004f9091c641162eeacb224cfd8db43b

MIT-0

実行証拠

宣言された環境と署名済みの実行を分けてあります。このサンプルが何をどこで実行したかをそのまま確認できます。

宣言された環境 go linux x64 go go gomod

環境	コントラクト	ステージ	実行日
go 1.26 · linux alpine/x64 · docker ed25519:d91480838ac982c9	PASS	compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS CONTAINER_RUN · golang@1	2026-08-17
go 1.26 · linux alpine/x64 · docker ed25519:2175b912ea1c23b1	PASS	compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS CONTAINER_RUN · golang@1	2026-08-18

HOW

ゴール: Handle singleflight DoChan per-caller buffered channels, unclosed channel semantics, abandoned consumer non-blocking delivery, and sync Do coexistence
パッケージ: golang.org/x/sync 0.22.0
シンボル: singleflight.Group.DoChan
Group.Do
singleflight.Result
runtime.Goexit
環境: go
作成日: 2026-08-17T20:38:05Z

assert singleflight.Group.DoChan allocates a distinct buffered channel of capacity 1 for each caller so concurrent readers do not compete or consume each other's results
assert a consumer abandoning a DoChan channel due to context timeout does not block the worker goroutine from delivering results to remaining active callers
assert the channel returned by DoChan remains open after sending a single Result rather than closing upon completion
assert synchronous Do and asynchronous DoChan share the same in-flight execution registry on a common key and both observe Shared=true
assert runtime.Goexit in the leader function propagates runtime.Goexit to duplicate callers waiting in synchronous Do rather than returning zero values