// Copyright (c) 2020 Tailscale Inc & AUTHORS All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package syncs

import "testing"

func TestWaitGroupChan(t *testing.T) {
	wg := NewWaitGroupChan()

	wantNotDone := func() {
		t.Helper()
		select {
		case <-wg.DoneChan():
			t.Fatal("done too early")
		default:
		}
	}

	wantDone := func() {
		t.Helper()
		select {
		case <-wg.DoneChan():
		default:
			t.Fatal("expected to be done")
		}
	}

	wg.Add(2)
	wantNotDone()

	wg.Decr()
	wantNotDone()

	wg.Decr()
	wantDone()
	wantDone()
}

func TestClosedChan(t *testing.T) {
	ch := ClosedChan()
	for i := 0; i < 2; i++ {
		select {
		case <-ch:
		default:
			t.Fatal("not closed")
		}
	}
}