nodejs-mozilla/test/parallel/test-stream-readable-emitte...

74 lines
2.1 KiB
JavaScript

'use strict';
const common = require('../common');
const assert = require('assert');
const Readable = require('stream').Readable;
const readable = new Readable({
read: () => {}
});
// Initialized to false.
assert.strictEqual(readable._readableState.emittedReadable, false);
const expected = [Buffer.from('foobar'), Buffer.from('quo'), null];
readable.on('readable', common.mustCall(() => {
// emittedReadable should be true when the readable event is emitted
assert.strictEqual(readable._readableState.emittedReadable, true);
assert.deepStrictEqual(readable.read(), expected.shift());
// emittedReadable is reset to false during read()
assert.strictEqual(readable._readableState.emittedReadable, false);
}, 3));
// When the first readable listener is just attached,
// emittedReadable should be false
assert.strictEqual(readable._readableState.emittedReadable, false);
// These trigger a single 'readable', as things are batched up
process.nextTick(common.mustCall(() => {
readable.push('foo');
}));
process.nextTick(common.mustCall(() => {
readable.push('bar');
}));
// These triggers two readable events
setImmediate(common.mustCall(() => {
readable.push('quo');
process.nextTick(common.mustCall(() => {
readable.push(null);
}));
}));
const noRead = new Readable({
read: () => {}
});
noRead.on('readable', common.mustCall(() => {
// emittedReadable should be true when the readable event is emitted
assert.strictEqual(noRead._readableState.emittedReadable, true);
noRead.read(0);
// emittedReadable is not reset during read(0)
assert.strictEqual(noRead._readableState.emittedReadable, true);
}));
noRead.push('foo');
noRead.push(null);
const flowing = new Readable({
read: () => {}
});
flowing.on('data', common.mustCall(() => {
// When in flowing mode, emittedReadable is always false.
assert.strictEqual(flowing._readableState.emittedReadable, false);
flowing.read();
assert.strictEqual(flowing._readableState.emittedReadable, false);
}, 3));
flowing.push('foooo');
flowing.push('bar');
flowing.push('quo');
process.nextTick(common.mustCall(() => {
flowing.push(null);
}));