1// Copyright 2021 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
5package maps
6
7import (
8	"math"
9	"strconv"
10	"testing"
11)
12
13var m1 = map[int]int{1: 2, 2: 4, 4: 8, 8: 16}
14var m2 = map[int]string{1: "2", 2: "4", 4: "8", 8: "16"}
15
16func TestEqual(t *testing.T) {
17	if !Equal(m1, m1) {
18		t.Errorf("Equal(%v, %v) = false, want true", m1, m1)
19	}
20	if Equal(m1, (map[int]int)(nil)) {
21		t.Errorf("Equal(%v, nil) = true, want false", m1)
22	}
23	if Equal((map[int]int)(nil), m1) {
24		t.Errorf("Equal(nil, %v) = true, want false", m1)
25	}
26	if !Equal[map[int]int, map[int]int](nil, nil) {
27		t.Error("Equal(nil, nil) = false, want true")
28	}
29	if ms := map[int]int{1: 2}; Equal(m1, ms) {
30		t.Errorf("Equal(%v, %v) = true, want false", m1, ms)
31	}
32
33	// Comparing NaN for equality is expected to fail.
34	mf := map[int]float64{1: 0, 2: math.NaN()}
35	if Equal(mf, mf) {
36		t.Errorf("Equal(%v, %v) = true, want false", mf, mf)
37	}
38}
39
40// equal is simply ==.
41func equal[T comparable](v1, v2 T) bool {
42	return v1 == v2
43}
44
45// equalNaN is like == except that all NaNs are equal.
46func equalNaN[T comparable](v1, v2 T) bool {
47	isNaN := func(f T) bool { return f != f }
48	return v1 == v2 || (isNaN(v1) && isNaN(v2))
49}
50
51// equalStr compares ints and strings.
52func equalIntStr(v1 int, v2 string) bool {
53	return strconv.Itoa(v1) == v2
54}
55
56func TestEqualFunc(t *testing.T) {
57	if !EqualFunc(m1, m1, equal[int]) {
58		t.Errorf("EqualFunc(%v, %v, equal) = false, want true", m1, m1)
59	}
60	if EqualFunc(m1, (map[int]int)(nil), equal[int]) {
61		t.Errorf("EqualFunc(%v, nil, equal) = true, want false", m1)
62	}
63	if EqualFunc((map[int]int)(nil), m1, equal[int]) {
64		t.Errorf("EqualFunc(nil, %v, equal) = true, want false", m1)
65	}
66	if !EqualFunc[map[int]int, map[int]int](nil, nil, equal[int]) {
67		t.Error("EqualFunc(nil, nil, equal) = false, want true")
68	}
69	if ms := map[int]int{1: 2}; EqualFunc(m1, ms, equal[int]) {
70		t.Errorf("EqualFunc(%v, %v, equal) = true, want false", m1, ms)
71	}
72
73	// Comparing NaN for equality is expected to fail.
74	mf := map[int]float64{1: 0, 2: math.NaN()}
75	if EqualFunc(mf, mf, equal[float64]) {
76		t.Errorf("EqualFunc(%v, %v, equal) = true, want false", mf, mf)
77	}
78	// But it should succeed using equalNaN.
79	if !EqualFunc(mf, mf, equalNaN[float64]) {
80		t.Errorf("EqualFunc(%v, %v, equalNaN) = false, want true", mf, mf)
81	}
82
83	if !EqualFunc(m1, m2, equalIntStr) {
84		t.Errorf("EqualFunc(%v, %v, equalIntStr) = false, want true", m1, m2)
85	}
86}
87
88func TestClone(t *testing.T) {
89	mc := Clone(m1)
90	if !Equal(mc, m1) {
91		t.Errorf("Clone(%v) = %v, want %v", m1, mc, m1)
92	}
93	mc[16] = 32
94	if Equal(mc, m1) {
95		t.Errorf("Equal(%v, %v) = true, want false", mc, m1)
96	}
97}
98
99func TestCloneNil(t *testing.T) {
100	var m1 map[string]int
101	mc := Clone(m1)
102	if mc != nil {
103		t.Errorf("Clone(%v) = %v, want %v", m1, mc, m1)
104	}
105}
106
107func TestCopy(t *testing.T) {
108	mc := Clone(m1)
109	Copy(mc, mc)
110	if !Equal(mc, m1) {
111		t.Errorf("Copy(%v, %v) = %v, want %v", m1, m1, mc, m1)
112	}
113	Copy(mc, map[int]int{16: 32})
114	want := map[int]int{1: 2, 2: 4, 4: 8, 8: 16, 16: 32}
115	if !Equal(mc, want) {
116		t.Errorf("Copy result = %v, want %v", mc, want)
117	}
118
119	type M1 map[int]bool
120	type M2 map[int]bool
121	Copy(make(M1), make(M2))
122}
123
124func TestDeleteFunc(t *testing.T) {
125	mc := Clone(m1)
126	DeleteFunc(mc, func(int, int) bool { return false })
127	if !Equal(mc, m1) {
128		t.Errorf("DeleteFunc(%v, true) = %v, want %v", m1, mc, m1)
129	}
130	DeleteFunc(mc, func(k, v int) bool { return k > 3 })
131	want := map[int]int{1: 2, 2: 4}
132	if !Equal(mc, want) {
133		t.Errorf("DeleteFunc result = %v, want %v", mc, want)
134	}
135}
136
137var n map[int]int
138
139func BenchmarkMapClone(b *testing.B) {
140	var m = make(map[int]int)
141	for i := 0; i < 1000000; i++ {
142		m[i] = i
143	}
144	b.ResetTimer()
145	for i := 0; i < b.N; i++ {
146		n = Clone(m)
147	}
148}
149
150func TestCloneWithDelete(t *testing.T) {
151	var m = make(map[int]int)
152	for i := 0; i < 32; i++ {
153		m[i] = i
154	}
155	for i := 8; i < 32; i++ {
156		delete(m, i)
157	}
158	m2 := Clone(m)
159	if len(m2) != 8 {
160		t.Errorf("len2(m2) = %d, want %d", len(m2), 8)
161	}
162	for i := 0; i < 8; i++ {
163		if m2[i] != m[i] {
164			t.Errorf("m2[%d] = %d, want %d", i, m2[i], m[i])
165		}
166	}
167}
168
169func TestCloneWithMapAssign(t *testing.T) {
170	var m = make(map[int]int)
171	const N = 25
172	for i := 0; i < N; i++ {
173		m[i] = i
174	}
175	m2 := Clone(m)
176	if len(m2) != N {
177		t.Errorf("len2(m2) = %d, want %d", len(m2), N)
178	}
179	for i := 0; i < N; i++ {
180		if m2[i] != m[i] {
181			t.Errorf("m2[%d] = %d, want %d", i, m2[i], m[i])
182		}
183	}
184}
185
186func TestCloneLarge(t *testing.T) {
187	// See issue 64474.
188	type K [17]float64 // > 128 bytes
189	type V [17]float64
190
191	var zero float64
192	negZero := -zero
193
194	for tst := 0; tst < 3; tst++ {
195		// Initialize m with a key and value.
196		m := map[K]V{}
197		var k1 K
198		var v1 V
199		m[k1] = v1
200
201		switch tst {
202		case 0: // nothing, just a 1-entry map
203		case 1:
204			// Add more entries to make it 2 buckets
205			// 1 entry already
206			// 7 more fill up 1 bucket
207			// 1 more to grow to 2 buckets
208			for i := 0; i < 7+1; i++ {
209				m[K{float64(i) + 1}] = V{}
210			}
211		case 2:
212			// Capture the map mid-grow
213			// 1 entry already
214			// 7 more fill up 1 bucket
215			// 5 more (13 total) fill up 2 buckets
216			// 13 more (26 total) fill up 4 buckets
217			// 1 more to start the 4->8 bucket grow
218			for i := 0; i < 7+5+13+1; i++ {
219				m[K{float64(i) + 1}] = V{}
220			}
221		}
222
223		// Clone m, which should freeze the map's contents.
224		c := Clone(m)
225
226		// Update m with new key and value.
227		k2, v2 := k1, v1
228		k2[0] = negZero
229		v2[0] = 1.0
230		m[k2] = v2
231
232		// Make sure c still has its old key and value.
233		for k, v := range c {
234			if math.Signbit(k[0]) {
235				t.Errorf("tst%d: sign bit of key changed; got %v want %v", tst, k, k1)
236			}
237			if v != v1 {
238				t.Errorf("tst%d: value changed; got %v want %v", tst, v, v1)
239			}
240		}
241	}
242}
243