nodejs-mozilla/test/parallel/test-stream2-readable-empty...

119 lines
3.4 KiB
JavaScript

// Copyright Joyent, Inc. and other Node contributors.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to permit
// persons to whom the Software is furnished to do so, subject to the
// following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
// USE OR OTHER DEALINGS IN THE SOFTWARE.
'use strict';
require('../common');
const assert = require('assert');
const Readable = require('stream').Readable;
test1();
test2();
function test1() {
const r = new Readable();
// Should not end when we get a Buffer.alloc(0) or '' as the _read
// result that just means that there is *temporarily* no data, but to
// go ahead and try again later.
//
// note that this is very unusual. it only works for crypto streams
// because the other side of the stream will call read(0) to cycle
// data through openssl. that's why setImmediate() is used to call
// r.read(0) again later, otherwise there is no more work being done
// and the process just exits.
const buf = Buffer.alloc(5, 'x');
let reads = 5;
r._read = function(n) {
switch (reads--) {
case 5:
return setImmediate(() => {
return r.push(buf);
});
case 4:
setImmediate(() => {
return r.push(Buffer.alloc(0));
});
return setImmediate(r.read.bind(r, 0));
case 3:
setImmediate(r.read.bind(r, 0));
return process.nextTick(() => {
return r.push(Buffer.alloc(0));
});
case 2:
setImmediate(r.read.bind(r, 0));
return r.push(Buffer.alloc(0)); // Not-EOF!
case 1:
return r.push(buf);
case 0:
return r.push(null); // EOF
default:
throw new Error('unreachable');
}
};
const results = [];
function flow() {
let chunk;
while (null !== (chunk = r.read()))
results.push(String(chunk));
}
r.on('readable', flow);
r.on('end', () => {
results.push('EOF');
});
flow();
process.on('exit', () => {
assert.deepStrictEqual(results, [ 'xxxxx', 'xxxxx', 'EOF' ]);
console.log('ok');
});
}
function test2() {
const r = new Readable({ encoding: 'base64' });
let reads = 5;
r._read = function(n) {
if (!reads--)
return r.push(null); // EOF
else
return r.push(Buffer.from('x'));
};
const results = [];
function flow() {
let chunk;
while (null !== (chunk = r.read()))
results.push(String(chunk));
}
r.on('readable', flow);
r.on('end', () => {
results.push('EOF');
});
flow();
process.on('exit', () => {
assert.deepStrictEqual(results, [ 'eHh4', 'eHg=', 'EOF' ]);
console.log('ok');
});
}