Merge pull request #252 from secretrobotron/issue249

[Issue249] Support for ArrayBuffer in Filer.Buffer r=ack

README.md

@@ -196,7 +196,7 @@ When in a node.js environment, native `Buffer`s can be used, or Filer.Buffer, wh
 to node's `Buffer`.  In a browser, you can use also use `Filer.Buffer`.
 
 NOTE: a `Filer.Buffer` in a browser is really an augmented `Uint8Array` (i.e., the node `Buffer` api
-methods are added to the instance). See https://github.com/feross/buffer for more details.
+methods are added to the instance). See https://github.com/feross/buffer for more details. Additionally, unlike native `Buffer`, `Filer.Buffer`'s constructor can accept `ArrayBuffer` objects, which will be interpreted as `Uint8Array`s.
 
 ####Filer.Path<a name="FilerPath"></a>
 

src/buffer.js

@@ -0,0 +1,23 @@
+function FilerBuffer (subject, encoding, nonZero) {
+
+  // Automatically turn ArrayBuffer into Uint8Array so that underlying
+  // Buffer code doesn't just throw away and ignore ArrayBuffer data.
+  if (subject instanceof ArrayBuffer) {
+    subject = new Uint8Array(subject);
+  }
+
+  return new Buffer(subject, encoding, nonZero);
+};
+
+// Inherit prototype from Buffer
+FilerBuffer.prototype = Object.create(Buffer.prototype);
+FilerBuffer.prototype.constructor = FilerBuffer;
+
+// Also copy static methods onto FilerBuffer ctor
+Object.keys(Buffer).forEach(function (p) {
+  if (Buffer.hasOwnProperty(p)) {
+    FilerBuffer[p] = Buffer[p];
+  }
+});
+
+module.exports = FilerBuffer;

src/index.js

@@ -1,6 +1,6 @@
 module.exports = {
   FileSystem: require('./filesystem/interface.js'),
-  Buffer: Buffer,
+  Buffer: require('./buffer.js'),
   Path: require('./path.js'),
   Errors: require('./errors.js')
 };

tests/bugs/issue249.js

@@ -0,0 +1,42 @@
+var Filer = require('../..');
+var util = require('../lib/test-utils.js');
+var expect = require('chai').expect;
+
+describe('Filer.Buffer should accept initialized ArrayBuffers, issue 249', function() {
+  beforeEach(util.setup);
+  afterEach(util.cleanup);
+
+  it('should accept an ArrayBuffer with a specified size', function(done) {
+    var buffer = new Filer.Buffer(new ArrayBuffer(5));
+    expect(buffer.length).to.equal(5);
+    done();
+  });
+});
+
+describe('Filer.Buffer static methods are in tact, issue 249', function() {
+  beforeEach(util.setup);
+  afterEach(util.cleanup);
+
+  it('should proxy Buffer.isBuffer', function(done) {
+    expect(Filer.Buffer.isBuffer(new Filer.Buffer([]))).to.equal(true);
+    expect(Filer.Buffer.isBuffer('')).to.equal(false);
+    done();
+  });
+
+  it('should proxy Buffer.isEncoding', function(done) {
+    expect(Filer.Buffer.isEncoding('utf8')).to.equal(true);
+    expect(Filer.Buffer.isEncoding('smoop')).to.equal(false);
+    done();
+  });
+
+  it('should proxy Buffer.byteLength', function(done) {
+    expect(Filer.Buffer.byteLength('01100111', 'binary')).to.equal(8);
+    done();
+  });
+
+  it('should proxy Buffer.concat', function(done) {
+    expect(Filer.Buffer.concat([new Filer.Buffer(1), new Filer.Buffer(2)]).length).to.equal(3);
+    done();
+  });
+});
+

tests/index.js

@@ -68,5 +68,6 @@ require("./spec/node-js/simple/test-fs-watch-recursive");
 require("./bugs/issue105");
 require("./bugs/issue106");
 require("./bugs/issue239");
+require("./bugs/issue249");
 require("./bugs/ls-depth-bug");
 require("./bugs/issue247.js");