fs: remove unnecessary usage of .hasOwnProperty()

PR-URL: #635
Reviewed-By: Vladimir Kurchatkin <[email protected]>

Author: jonathanong

lib/fs.js

@@ -1608,21 +1608,20 @@ function ReadStream(path, options) {
     return new ReadStream(path, options);
 
   // a little bit bigger buffer and water marks by default
-  options = util._extend({
-    highWaterMark: 64 * 1024
-  }, options || {});
+  options = Object.create(options || {});
+  if (options.highWaterMark === undefined)
+    options.highWaterMark = 64 * 1024;
 
   Readable.call(this, options);
 
   this.path = path;
-  this.fd = options.hasOwnProperty('fd') ? options.fd : null;
-  this.flags = options.hasOwnProperty('flags') ? options.flags : 'r';
-  this.mode = options.hasOwnProperty('mode') ? options.mode : 0o666;
-
-  this.start = options.hasOwnProperty('start') ? options.start : undefined;
-  this.end = options.hasOwnProperty('end') ? options.end : undefined;
-  this.autoClose = options.hasOwnProperty('autoClose') ?
-      options.autoClose : true;
+  this.fd = options.fd === undefined ? null : options.fd;
+  this.flags = options.flags === undefined ? 'r' : options.flags;
+  this.mode = options.mode === undefined ? 0o666 : options.mode;
+
+  this.start = options.start === undefined ? undefined : options.start;
+  this.end = options.end === undefined ? undefined : options.end;
+  this.autoClose = options.autoClose === undefined ? true : options.autoClose;
   this.pos = undefined;
 
   if (this.start !== undefined) {
@@ -1779,13 +1778,11 @@ function WriteStream(path, options) {
   Writable.call(this, options);
 
   this.path = path;
-  this.fd = null;
-
-  this.fd = options.hasOwnProperty('fd') ? options.fd : null;
-  this.flags = options.hasOwnProperty('flags') ? options.flags : 'w';
-  this.mode = options.hasOwnProperty('mode') ? options.mode : 0o666;
+  this.fd = options.fd === undefined ? null : options.fd;
+  this.flags = options.flags === undefined ? 'w' : options.flags;
+  this.mode = options.mode === undefined ? 0o666 : options.mode;
 
-  this.start = options.hasOwnProperty('start') ? options.start : undefined;
+  this.start = options.start === undefined ? undefined : options.start;
   this.pos = undefined;
   this.bytesWritten = 0;
 
@@ -1865,8 +1862,7 @@ function SyncWriteStream(fd, options) {
   this.fd = fd;
   this.writable = true;
   this.readable = false;
-  this.autoClose = options.hasOwnProperty('autoClose') ?
-      options.autoClose : true;
+  this.autoClose = options.autoClose === undefined ? true : options.autoClose;
 }
 
 util.inherits(SyncWriteStream, Stream);

test/parallel/test-fs-read-stream-inherit.js

@@ -0,0 +1,180 @@
+var common = require('../common');
+var assert = require('assert');
+
+// TODO Improved this test. test_ca.pem is too small. A proper test would
+// great a large utf8 (with multibyte chars) file and stream it in,
+// performing sanity checks throughout.
+
+var path = require('path');
+var fs = require('fs');
+var fn = path.join(common.fixturesDir, 'elipses.txt');
+var rangeFile = path.join(common.fixturesDir, 'x.txt');
+
+var callbacks = { open: 0, end: 0, close: 0 };
+
+var paused = false;
+
+var file = fs.ReadStream(fn);
+
+file.on('open', function(fd) {
+  file.length = 0;
+  callbacks.open++;
+  assert.equal('number', typeof fd);
+  assert.ok(file.readable);
+
+  // GH-535
+  file.pause();
+  file.resume();
+  file.pause();
+  file.resume();
+});
+
+file.on('data', function(data) {
+  assert.ok(data instanceof Buffer);
+  assert.ok(!paused);
+  file.length += data.length;
+
+  paused = true;
+  file.pause();
+
+  setTimeout(function() {
+    paused = false;
+    file.resume();
+  }, 10);
+});
+
+
+file.on('end', function(chunk) {
+  callbacks.end++;
+});
+
+
+file.on('close', function() {
+  callbacks.close++;
+
+  //assert.equal(fs.readFileSync(fn), fileContent);
+});
+
+var file3 = fs.createReadStream(fn, Object.create({encoding: 'utf8'}));
+file3.length = 0;
+file3.on('data', function(data) {
+  assert.equal('string', typeof(data));
+  file3.length += data.length;
+
+  for (var i = 0; i < data.length; i++) {
+    // http://www.fileformat.info/info/unicode/char/2026/index.htm
+    assert.equal('\u2026', data[i]);
+  }
+});
+
+file3.on('close', function() {
+  callbacks.close++;
+});
+
+process.on('exit', function() {
+  assert.equal(1, callbacks.open);
+  assert.equal(1, callbacks.end);
+  assert.equal(2, callbacks.close);
+  assert.equal(30000, file.length);
+  assert.equal(10000, file3.length);
+  console.error('ok');
+});
+
+var file4 = fs.createReadStream(rangeFile, Object.create({bufferSize: 1, start: 1, end: 2}));
+assert.equal(file4.start, 1);
+assert.equal(file4.end, 2);
+var contentRead = '';
+file4.on('data', function(data) {
+  contentRead += data.toString('utf-8');
+});
+file4.on('end', function(data) {
+  assert.equal(contentRead, 'yz');
+});
+
+var file5 = fs.createReadStream(rangeFile, Object.create({bufferSize: 1, start: 1}));
+assert.equal(file5.start, 1);
+file5.data = '';
+file5.on('data', function(data) {
+  file5.data += data.toString('utf-8');
+});
+file5.on('end', function() {
+  assert.equal(file5.data, 'yz\n');
+});
+
+// https://github.com/joyent/node/issues/2320
+var file6 = fs.createReadStream(rangeFile, Object.create({bufferSize: 1.23, start: 1}));
+assert.equal(file6.start, 1);
+file6.data = '';
+file6.on('data', function(data) {
+  file6.data += data.toString('utf-8');
+});
+file6.on('end', function() {
+  assert.equal(file6.data, 'yz\n');
+});
+
+assert.throws(function() {
+  fs.createReadStream(rangeFile, Object.create({start: 10, end: 2}));
+}, /start must be <= end/);
+
+var stream = fs.createReadStream(rangeFile, Object.create({ start: 0, end: 0 }));
+assert.equal(stream.start, 0);
+assert.equal(stream.end, 0);
+stream.data = '';
+
+stream.on('data', function(chunk) {
+  stream.data += chunk;
+});
+
+stream.on('end', function() {
+  assert.equal('x', stream.data);
+});
+
+// pause and then resume immediately.
+var pauseRes = fs.createReadStream(rangeFile);
+pauseRes.pause();
+pauseRes.resume();
+
+var file7 = fs.createReadStream(rangeFile, Object.create({autoClose: false }));
+assert.equal(file7.autoClose, false);
+file7.on('data', function() {});
+file7.on('end', function() {
+  process.nextTick(function() {
+    assert(!file7.closed);
+    assert(!file7.destroyed);
+    file7Next();
+  });
+});
+
+function file7Next(){
+  // This will tell us if the fd is usable again or not.
+  file7 = fs.createReadStream(null, Object.create({fd: file7.fd, start: 0 }));
+  file7.data = '';
+  file7.on('data', function(data) {
+    file7.data += data;
+  });
+  file7.on('end', function(err) {
+    assert.equal(file7.data, 'xyz\n');
+  });
+}
+
+// Just to make sure autoClose won't close the stream because of error.
+var file8 = fs.createReadStream(null, Object.create({fd: 13337, autoClose: false }));
+file8.on('data', function() {});
+file8.on('error', common.mustCall(function() {}));
+
+// Make sure stream is destroyed when file does not exist.
+var file9 = fs.createReadStream('/path/to/file/that/does/not/exist');
+file9.on('data', function() {});
+file9.on('error', common.mustCall(function() {}));
+
+process.on('exit', function() {
+  assert(file7.closed);
+  assert(file7.destroyed);
+
+  assert(!file8.closed);
+  assert(!file8.destroyed);
+  assert(file8.fd);
+
+  assert(!file9.closed);
+  assert(file9.destroyed);
+});