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
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
|
// META: global=window,worker,shadowrealm
// META: script=../resources/test-utils.js
// META: script=../resources/rs-utils.js
'use strict';
promise_test(t => {
const randomSource = new RandomPushSource();
let cancellationFinished = false;
const rs = new ReadableStream({
start(c) {
randomSource.ondata = c.enqueue.bind(c);
randomSource.onend = c.close.bind(c);
randomSource.onerror = c.error.bind(c);
},
pull() {
randomSource.readStart();
},
cancel() {
randomSource.readStop();
return new Promise(resolve => {
t.step_timeout(() => {
cancellationFinished = true;
resolve();
}, 1);
});
}
});
const reader = rs.getReader();
// We call delay multiple times to avoid cancelling too early for the
// source to enqueue at least one chunk.
const cancel = delay(5).then(() => delay(5)).then(() => delay(5)).then(() => {
const cancelPromise = reader.cancel();
assert_false(cancellationFinished, 'cancellation in source should happen later');
return cancelPromise;
});
return readableStreamToArray(rs, reader).then(chunks => {
assert_greater_than(chunks.length, 0, 'at least one chunk should be read');
for (let i = 0; i < chunks.length; i++) {
assert_equals(chunks[i].length, 128, 'chunk ' + i + ' should have 128 bytes');
}
return cancel;
}).then(() => {
assert_true(cancellationFinished, 'it returns a promise that is fulfilled when the cancellation finishes');
});
}, 'ReadableStream cancellation: integration test on an infinite stream derived from a random push source');
test(() => {
let recordedReason;
const rs = new ReadableStream({
cancel(reason) {
recordedReason = reason;
}
});
const passedReason = new Error('Sorry, it just wasn\'t meant to be.');
rs.cancel(passedReason);
assert_equals(recordedReason, passedReason,
'the error passed to the underlying source\'s cancel method should equal the one passed to the stream\'s cancel');
}, 'ReadableStream cancellation: cancel(reason) should pass through the given reason to the underlying source');
promise_test(() => {
const rs = new ReadableStream({
start(c) {
c.enqueue('a');
c.close();
},
cancel() {
assert_unreached('underlying source cancel() should not have been called');
}
});
const reader = rs.getReader();
return rs.cancel().then(() => {
assert_unreached('cancel() should be rejected');
}, e => {
assert_equals(e.name, 'TypeError', 'cancel() should be rejected with a TypeError');
}).then(() => {
return reader.read();
}).then(result => {
assert_object_equals(result, { value: 'a', done: false }, 'read() should still work after the attempted cancel');
return reader.closed;
});
}, 'ReadableStream cancellation: cancel() on a locked stream should fail and not call the underlying source cancel');
promise_test(() => {
let cancelReceived = false;
const cancelReason = new Error('I am tired of this stream, I prefer to cancel it');
const rs = new ReadableStream({
cancel(reason) {
cancelReceived = true;
assert_equals(reason, cancelReason, 'cancellation reason given to the underlying source should be equal to the one passed');
}
});
return rs.cancel(cancelReason).then(() => {
assert_true(cancelReceived);
});
}, 'ReadableStream cancellation: should fulfill promise when cancel callback went fine');
promise_test(() => {
const rs = new ReadableStream({
cancel() {
return 'Hello';
}
});
return rs.cancel().then(v => {
assert_equals(v, undefined, 'cancel() return value should be fulfilled with undefined');
});
}, 'ReadableStream cancellation: returning a value from the underlying source\'s cancel should not affect the fulfillment value of the promise returned by the stream\'s cancel');
promise_test(() => {
const thrownError = new Error('test');
let cancelCalled = false;
const rs = new ReadableStream({
cancel() {
cancelCalled = true;
throw thrownError;
}
});
return rs.cancel('test').then(() => {
assert_unreached('cancel should reject');
}, e => {
assert_true(cancelCalled);
assert_equals(e, thrownError);
});
}, 'ReadableStream cancellation: should reject promise when cancel callback raises an exception');
promise_test(() => {
const cancelReason = new Error('test');
const rs = new ReadableStream({
cancel(error) {
assert_equals(error, cancelReason);
return delay(1);
}
});
return rs.cancel(cancelReason);
}, 'ReadableStream cancellation: if the underlying source\'s cancel method returns a promise, the promise returned by the stream\'s cancel should fulfill when that one does (1)');
promise_test(t => {
let resolveSourceCancelPromise;
let sourceCancelPromiseHasFulfilled = false;
const rs = new ReadableStream({
cancel() {
const sourceCancelPromise = new Promise(resolve => resolveSourceCancelPromise = resolve);
sourceCancelPromise.then(() => {
sourceCancelPromiseHasFulfilled = true;
});
return sourceCancelPromise;
}
});
t.step_timeout(() => resolveSourceCancelPromise('Hello'), 1);
return rs.cancel().then(value => {
assert_true(sourceCancelPromiseHasFulfilled, 'cancel() return value should be fulfilled only after the promise returned by the underlying source\'s cancel');
assert_equals(value, undefined, 'cancel() return value should be fulfilled with undefined');
});
}, 'ReadableStream cancellation: if the underlying source\'s cancel method returns a promise, the promise returned by the stream\'s cancel should fulfill when that one does (2)');
promise_test(t => {
let rejectSourceCancelPromise;
let sourceCancelPromiseHasRejected = false;
const rs = new ReadableStream({
cancel() {
const sourceCancelPromise = new Promise((resolve, reject) => rejectSourceCancelPromise = reject);
sourceCancelPromise.catch(() => {
sourceCancelPromiseHasRejected = true;
});
return sourceCancelPromise;
}
});
const errorInCancel = new Error('Sorry, it just wasn\'t meant to be.');
t.step_timeout(() => rejectSourceCancelPromise(errorInCancel), 1);
return rs.cancel().then(() => {
assert_unreached('cancel() return value should be rejected');
}, r => {
assert_true(sourceCancelPromiseHasRejected, 'cancel() return value should be rejected only after the promise returned by the underlying source\'s cancel');
assert_equals(r, errorInCancel, 'cancel() return value should be rejected with the underlying source\'s rejection reason');
});
}, 'ReadableStream cancellation: if the underlying source\'s cancel method returns a promise, the promise returned by the stream\'s cancel should reject when that one does');
promise_test(() => {
const rs = new ReadableStream({
start() {
return new Promise(() => {});
},
pull() {
assert_unreached('pull should not have been called');
}
});
return Promise.all([rs.cancel(), rs.getReader().closed]);
}, 'ReadableStream cancellation: cancelling before start finishes should prevent pull() from being called');
|
