1// Copyright (c) 2021 Uber Technologies, Inc.
2//
3// Permission is hereby granted, free of charge, to any person obtaining a copy
4// of this software and associated documentation files (the "Software"), to deal
5// in the Software without restriction, including without limitation the rights
6// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
7// copies of the Software, and to permit persons to whom the Software is
8// furnished to do so, subject to the following conditions:
9//
10// The above copyright notice and this permission notice shall be included in
11// all copies or substantial portions of the Software.
12//
13// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
14// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
15// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
16// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
17// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
18// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
19// THE SOFTWARE.
20
21package atomic
22
23import (
24	"testing"
25	"time"
26
27	"github.com/stretchr/testify/assert"
28	"github.com/stretchr/testify/require"
29)
30
31func TestTime(t *testing.T) {
32	start := time.Date(2021, 6, 17, 9, 10, 0, 0, time.UTC)
33	atom := NewTime(start)
34
35	require.Equal(t, start, atom.Load(), "Load didn't work")
36	require.Equal(t, time.Time{}, NewTime(time.Time{}).Load(), "Default time value is wrong")
37}
38
39func TestTimeLocation(t *testing.T) {
40	// Check TZ data hasn't been lost from load/store.
41	ny, err := time.LoadLocation("America/New_York")
42	require.NoError(t, err, "Failed to load location")
43	nyTime := NewTime(time.Date(2021, 1, 1, 0, 0, 0, 0, ny))
44
45	var atom Time
46	atom.Store(nyTime.Load())
47
48	assert.Equal(t, ny, atom.Load().Location(), "Location information is wrong")
49}
50
51func TestLargeTime(t *testing.T) {
52	// Check "large/small" time that are beyond int64 ns
53	// representation (< year 1678 or > year 2262) can be
54	// correctly load/store'd.
55	t.Parallel()
56
57	t.Run("future", func(t *testing.T) {
58		future := time.Date(2262, 12, 31, 0, 0, 0, 0, time.UTC)
59		atom := NewTime(future)
60		dayAfterFuture := atom.Load().AddDate(0, 1, 0)
61
62		atom.Store(dayAfterFuture)
63		assert.Equal(t, 2263, atom.Load().Year())
64	})
65
66	t.Run("past", func(t *testing.T) {
67		past := time.Date(1678, 1, 1, 0, 0, 0, 0, time.UTC)
68		atom := NewTime(past)
69		dayBeforePast := atom.Load().AddDate(0, -1, 0)
70
71		atom.Store(dayBeforePast)
72		assert.Equal(t, 1677, atom.Load().Year())
73	})
74}
75
76func TestMonotonic(t *testing.T) {
77	before := NewTime(time.Now())
78	time.Sleep(15 * time.Millisecond)
79	after := NewTime(time.Now())
80
81	// try loading/storing before and test monotonic clock value hasn't been lost
82	bt := before.Load()
83	before.Store(bt)
84	d := after.Load().Sub(before.Load())
85	assert.True(t, 15 <= d.Milliseconds())
86}
87