libgo/go/time/tick_test.go

   1 // Copyright 2009 The Go Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style
   3 // license that can be found in the LICENSE file.
   4
   5 package time_test
   6
   7 import (
   8         "testing"
   9         . "time"
  10 )
  11
  12 func TestTicker(t *testing.T) {
  13         const Count = 10
  14         Delta := 100 * Millisecond
  15         ticker := NewTicker(Delta)
  16         t0 := Now()
  17         for i := 0; i < Count; i++ {
  18                 <-ticker.C
  19         }
  20         ticker.Stop()
  21         t1 := Now()
  22         dt := t1.Sub(t0)
  23         target := Delta * Count
  24         slop := target * 2 / 10
  25         if dt < target-slop || (!testing.Short() && dt > target+slop) {
  26                 t.Fatalf("%d %s ticks took %s, expected [%s,%s]", Count, Delta, dt, target-slop, target+slop)
  27         }
  28         // Now test that the ticker stopped
  29         Sleep(2 * Delta)
  30         select {
  31         case <-ticker.C:
  32                 t.Fatal("Ticker did not shut down")
  33         default:
  34                 // ok
  35         }
  36 }
  37
  38 // Test that a bug tearing down a ticker has been fixed.  This routine should not deadlock.
  39 func TestTeardown(t *testing.T) {
  40         Delta := 100 * Millisecond
  41         if testing.Short() {
  42                 Delta = 20 * Millisecond
  43         }
  44         for i := 0; i < 3; i++ {
  45                 ticker := NewTicker(Delta)
  46                 <-ticker.C
  47                 ticker.Stop()
  48         }
  49 }
  50
  51 // Test the Tick convenience wrapper.
  52 func TestTick(t *testing.T) {
  53         // Test that giving a negative duration returns nil.
  54         if got := Tick(-1); got != nil {
  55                 t.Errorf("Tick(-1) = %v; want nil", got)
  56         }
  57 }
  58
  59 // Test that NewTicker panics when given a duration less than zero.
  60 func TestNewTickerLtZeroDuration(t *testing.T) {
  61         defer func() {
  62                 if err := recover(); err == nil {
  63                         t.Errorf("NewTicker(-1) should have panicked")
  64                 }
  65         }()
  66         NewTicker(-1)
  67 }
  68
  69 func BenchmarkTicker(b *testing.B) {
  70         ticker := NewTicker(1)
  71         b.ResetTimer()
  72         b.StartTimer()
  73         for i := 0; i < b.N; i++ {
  74                 <-ticker.C
  75         }
  76         b.StopTimer()
  77         ticker.Stop()
  78 }