cond_test.go

package main

import (
	"testing"
	"sync"
	"sync/atomic"
)

func TestOneBarrier(t *testing.T) {
	expected := int32(2)
	actual := int32(0)

	var barrier sync.WaitGroup
	finished := make(chan bool, expected)

        barrier.Add(expected)

	for i := int32(0); i < expected; i++ {
		go func() {
		        barrier.Done()
		        barrier.Wait()
			atomic.AddInt32(&actual, 1)
			finished <- true
		}()
	}

	for i := int32(0); i < expected; i++ {
		<-finished
	}

	if actual != expected {
		t.Errorf("actual=%d expected=%d\n", actual, expected)
	}
}

func TestTwoBarriers(t *testing.T) {
	expected := int32(2)
	actual := int32(0)

	var ready sync.WaitGroup
	var completed sync.WaitGroup

        barrier.Add(expected)
        completed.Add(expected)

	for i := int32(0); i < expected; i++ {
		go func() {
		        ready.Done()
		        ready.Wait()
			atomic.AddInt32(&actual, 1)
			completed.Done()
		}()
	}

	completed.Wait()

	if actual != expected {
		t.Errorf("actual=%d expected=%d\n", actual, expected)
	}
}