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// 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';
const common = require('../common');
const assert = require('assert');
// This test verifies that:
// 1. unshift() does not cause colliding _read() calls.
// 2. unshift() after the 'end' event is an error, but after the EOF
// signalling null, it is ok, and just creates a new readable chunk.
// 3. push() after the EOF signaling null is an error.
// 4. _read() is not called after pushing the EOF null chunk.
const stream = require('stream');
const hwm = 10;
const r = stream.Readable({ highWaterMark: hwm });
const chunks = 10;
const data = Buffer.allocUnsafe(chunks * hwm + Math.ceil(hwm / 2));
for (let i = 0; i < data.length; i++) {
const c = 'asdf'.charCodeAt(i % 4);
data[i] = c;
}
let pos = 0;
let pushedNull = false;
r._read = function(n) {
assert(!pushedNull, '_read after null push');
// every third chunk is fast
push(!(chunks % 3));
function push(fast) {
assert(!pushedNull, 'push() after null push');
const c = pos >= data.length ? null : data.slice(pos, pos + n);
pushedNull = c === null;
if (fast) {
pos += n;
r.push(c);
if (c === null) pushError();
} else {
setTimeout(function() {
pos += n;
r.push(c);
if (c === null) pushError();
}, 1);
}
}
};
function pushError() {
assert.throws(function() {
r.push(Buffer.allocUnsafe(1));
}, /^Error: stream.push\(\) after EOF$/);
}
const w = stream.Writable();
const written = [];
w._write = function(chunk, encoding, cb) {
written.push(chunk.toString());
cb();
};
r.on('end', common.mustCall(function() {
assert.throws(function() {
r.unshift(Buffer.allocUnsafe(1));
}, /^Error: stream.unshift\(\) after end event$/);
w.end();
}));
r.on('readable', function() {
let chunk;
while (null !== (chunk = r.read(10))) {
w.write(chunk);
if (chunk.length > 4)
r.unshift(Buffer.from('1234'));
}
});
w.on('finish', common.mustCall(function() {
// each chunk should start with 1234, and then be asfdasdfasdf...
// The first got pulled out before the first unshift('1234'), so it's
// lacking that piece.
assert.strictEqual(written[0], 'asdfasdfas');
let asdf = 'd';
console.error('0: %s', written[0]);
for (let i = 1; i < written.length; i++) {
console.error('%s: %s', i.toString(32), written[i]);
assert.strictEqual(written[i].slice(0, 4), '1234');
for (let j = 4; j < written[i].length; j++) {
const c = written[i].charAt(j);
assert.strictEqual(c, asdf);
switch (asdf) {
case 'a': asdf = 's'; break;
case 's': asdf = 'd'; break;
case 'd': asdf = 'f'; break;
case 'f': asdf = 'a'; break;
}
}
}
}));
process.on('exit', function() {
assert.strictEqual(written.length, 18);
console.log('ok');
});
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