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
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
|
// Test String.prototype.charAt with out-of-bounds indices.
function* characters(...ranges) {
for (let [start, end] of ranges) {
for (let i = start; i <= end; ++i) {
yield i;
}
}
}
const empty = [];
const ascii = [...characters(
[0x41, 0x5A], // A..Z
[0x61, 0x7A], // a..z
)];
const latin1 = [...characters(
[0xC0, 0xFF], // À..ÿ
)];
const twoByte = [...characters(
[0x100, 0x17E], // Ā..ž
)];
function atomize(s) {
return Object.keys({[s]: 0})[0];
}
function codePoints() {
return [empty, ascii, latin1, twoByte];
}
function toRope(s) {
// Ropes have at least two characters.
if (s.length < 2) {
return s;
}
if (s.length === 2) {
return newRope(s[0], s[1]);
}
return newRope(s[0], s.substring(1));
}
function makeStrings() {
let strings = codePoints()
.map(codePoints => String.fromCodePoint(...codePoints))
.flatMap(x => [
x,
toRope(x),
newString(x, {twoByte: true}),
atomize(x),
]);
return strings;
}
function testNegativeIndexConstant() {
let strings = makeStrings();
for (let i = 0; i < 200; ++i) {
let str = strings[i % strings.length];
let ch = str.charAt(-1);
assertEq(ch, "");
}
}
for (let i = 0; i < 2; ++i) {
testNegativeIndexConstant();
}
function testNegativeIndexVariable() {
let indices = [-1, -2];
let strings = makeStrings();
for (let i = 0; i < 200; ++i) {
let str = strings[i % strings.length];
let ch = str.charAt(indices[i & 1]);
assertEq(ch, "");
}
}
for (let i = 0; i < 2; ++i) {
testNegativeIndexVariable();
}
function testNegativeOrValidIndex() {
let indices = [-1, 0];
let strings = makeStrings();
// Number of string kinds created in makeStrings.
const N = 4;
let cpoints = codePoints();
assertEq(strings.length, cpoints.length * N);
for (let i = 0; i < 200; ++i) {
let str = strings[i % strings.length];
let index = indices[i & 1];
let ch = str.charAt(index);
let cp = cpoints[Math.trunc((i % strings.length) / N)];
assertEq(ch, (0 <= index && index < cp.length ? String.fromCodePoint(cp[index]) : ""));
}
}
for (let i = 0; i < 2; ++i) {
testNegativeOrValidIndex();
}
function testTooLargeIndexConstant() {
let strings = makeStrings();
for (let i = 0; i < 200; ++i) {
let str = strings[i % strings.length];
let ch = str.charAt(1000);
assertEq(ch, "");
}
}
for (let i = 0; i < 2; ++i) {
testTooLargeIndexConstant();
}
function testTooLargeIndexVariable() {
let indices = [1000, 2000];
let strings = makeStrings();
for (let i = 0; i < 200; ++i) {
let str = strings[i % strings.length];
let ch = str.charAt(indices[i & 1]);
assertEq(ch, "");
}
}
for (let i = 0; i < 2; ++i) {
testTooLargeIndexVariable();
}
function testTooLargeOrValidIndex() {
let indices = [1000, 0];
let strings = makeStrings();
// Number of string kinds created in makeStrings.
const N = 4;
let cpoints = codePoints();
assertEq(strings.length, cpoints.length * N);
for (let i = 0; i < 200; ++i) {
let str = strings[i % strings.length];
let index = indices[i & 1];
let ch = str.charAt(index);
let cp = cpoints[Math.trunc((i % strings.length) / N)];
assertEq(ch, (0 <= index && index < cp.length ? String.fromCodePoint(cp[index]) : ""));
}
}
for (let i = 0; i < 2; ++i) {
testTooLargeOrValidIndex();
}
|
