summaryrefslogtreecommitdiff
path: root/src/pkg/time/sleep_test.go
blob: 9e36288f886306225914133c8dbcc9fbb774ca3e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
// Copyright 2009 The Go 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 time_test

import (
	"os"
	"syscall"
	"testing"
	"sort"
	. "time"
)

func TestSleep(t *testing.T) {
	const delay = int64(100e6)
	go func() {
		Sleep(delay / 2)
		syscall.Kill(os.Getpid(), syscall.SIGCHLD)
	}()
	start := Nanoseconds()
	Sleep(delay)
	duration := Nanoseconds() - start
	if duration < delay {
		t.Fatalf("Sleep(%d) slept for only %d ns", delay, duration)
	}
}

// Test the basic function calling behavior. Correct queueing
// behavior is tested elsewhere, since After and AfterFunc share
// the same code.
func TestAfterFunc(t *testing.T) {
	i := 10
	c := make(chan bool)
	var f func()
	f = func() {
		i--
		if i >= 0 {
			AfterFunc(0, f)
			Sleep(1e9)
		} else {
			c <- true
		}
	}

	AfterFunc(0, f)
	<-c
}

func BenchmarkAfterFunc(b *testing.B) {
	i := b.N
	c := make(chan bool)
	var f func()
	f = func() {
		i--
		if i >= 0 {
			AfterFunc(0, f)
		} else {
			c <- true
		}
	}

	AfterFunc(0, f)
	<-c
}

func TestAfter(t *testing.T) {
	const delay = int64(100e6)
	start := Nanoseconds()
	end := <-After(delay)
	if duration := Nanoseconds() - start; duration < delay {
		t.Fatalf("After(%d) slept for only %d ns", delay, duration)
	}
	if min := start + delay; end < min {
		t.Fatalf("After(%d) expect >= %d, got %d", delay, min, end)
	}
}

func TestAfterTick(t *testing.T) {
	const (
		Delta = 100 * 1e6
		Count = 10
	)
	t0 := Nanoseconds()
	for i := 0; i < Count; i++ {
		<-After(Delta)
	}
	t1 := Nanoseconds()
	ns := t1 - t0
	target := int64(Delta * Count)
	slop := target * 2 / 10
	if ns < target-slop || ns > target+slop {
		t.Fatalf("%d ticks of %g ns took %g ns, expected %g", Count, float64(Delta), float64(ns), float64(target))
	}
}

var slots = []int{5, 3, 6, 6, 6, 1, 1, 2, 7, 9, 4, 8, 0}

type afterResult struct {
	slot int
	t    int64
}

func await(slot int, result chan<- afterResult, ac <-chan int64) {
	result <- afterResult{slot, <-ac}
}

func TestAfterQueuing(t *testing.T) {
	const (
		Delta = 100 * 1e6
	)
	// make the result channel buffered because we don't want
	// to depend on channel queueing semantics that might
	// possibly change in the future.
	result := make(chan afterResult, len(slots))

	t0 := Nanoseconds()
	for _, slot := range slots {
		go await(slot, result, After(int64(slot)*Delta))
	}
	sort.SortInts(slots)
	for _, slot := range slots {
		r := <-result
		if r.slot != slot {
			t.Fatalf("after queue got slot %d, expected %d", r.slot, slot)
		}
		ns := r.t - t0
		target := int64(slot * Delta)
		slop := int64(Delta) / 4
		if ns < target-slop || ns > target+slop {
			t.Fatalf("after queue slot %d arrived at %g, expected [%g,%g]", slot, float64(ns), float64(target-slop), float64(target+slop))
		}
	}
}