fix unit test

pkg/workerpool/pool.go

@@ -44,7 +44,6 @@ type EventHandle interface {
 	// SetTimer is used to provide a function that is periodic called, as long as the EventHandle has not been unregistered.
 	// The current implementation uses as the base clock source a ticker whose interval is the const workerPoolDefaultClockSourceInterval.
 	// DO NOT set an interval less than workerPoolDefaultClockSourceInterval.
-	// DO NOT set an interval less than workerPoolDefaultClockSourceInterval.
 	// Cancelling `ctx` here will cancel the on-going or next execution of `f`.
 	SetTimer(ctx context.Context, interval time.Duration, f func(ctx context.Context) error) EventHandle
 

pkg/workerpool/pool_test.go

@@ -379,7 +379,7 @@ func (s *workerPoolSuite) TestCancelByAddEventContext(c *check.C) {
 	pool := newDefaultPoolImpl(&defaultHasher{}, 4)
 	go func() {
 		err := pool.Run(poolCtx)
-		c.Assert(err, check.IsNil)
+		c.Assert(err, check.ErrorMatches, ".*context canceled.*")
 	}()
 
 	ctx, cancel := context.WithTimeout(context.Background(), time.Second*20)