kubernetes/staging/src/k8s.io/apiserver/pkg/util/flowcontrol/fairqueuing/testing/promise/counting.go

type countingPromise …

var _ …

// NewCountingWriteOnce creates a WriteOnce that uses locking and counts goroutine activity.
//
// The final three arguments are like those for a regular WriteOnce factory:
// - an optional initial value,
// - an optional "done" channel,
// - the value that is Set after the "done" channel becomes selectable.
// Note that for this implementation, the reaction to `doneCh`
// becoming selectable does not wait for a Get.
// If `doneCh != nil` then the caller promises to close it reasonably promptly
// (to the degree allowed by the Go runtime scheduler), and increment the
// goroutine counter before that.
// The WriteOnce's Get method must be called without the lock held.
// The WriteOnce's Set method must be called with the lock held.
func NewCountingWriteOnce(activeCounter counter.GoRoutineCounter, lock sync.Locker, initial interface{ … }

func (p *countingPromise) Get() interface{ … }

func (p *countingPromise) Set(value interface{ … }