Add support for buffer configuration. (protobufjs#1257)

* Added support for buffer configuration.

* Fixed tests for node 4.

* Fixed deprecated Buffer methods.

src/index-minimal.js

@@ -27,10 +27,10 @@ protobuf.configure    = configure;
  * @returns {undefined}
  */
 function configure() {
-    protobuf.Reader._configure(protobuf.BufferReader);
     protobuf.util._configure();
+    protobuf.Writer._configure(protobuf.BufferWriter);
+    protobuf.Reader._configure(protobuf.BufferReader);
 }
 
 // Set up buffer utility according to the environment
-protobuf.Writer._configure(protobuf.BufferWriter);
 configure();

src/reader.js

@@ -53,24 +53,28 @@ var create_array = typeof Uint8Array !== "undefined"
         throw Error("illegal buffer");
     };
 
+var create = function create() {
+    return util.Buffer
+        ? function create_buffer_setup(buffer) {
+            return (Reader.create = function create_buffer(buffer) {
+                return util.Buffer.isBuffer(buffer)
+                    ? new BufferReader(buffer)
+                    /* istanbul ignore next */
+                    : create_array(buffer);
+            })(buffer);
+        }
+        /* istanbul ignore next */
+        : create_array;
+};
+
 /**
  * Creates a new reader using the specified buffer.
  * @function
  * @param {Uint8Array|Buffer} buffer Buffer to read from
  * @returns {Reader|BufferReader} A {@link BufferReader} if `buffer` is a Buffer, otherwise a {@link Reader}
  * @throws {Error} If `buffer` is not a valid buffer
  */
-Reader.create = util.Buffer
-    ? function create_buffer_setup(buffer) {
-        return (Reader.create = function create_buffer(buffer) {
-            return util.Buffer.isBuffer(buffer)
-                ? new BufferReader(buffer)
-                /* istanbul ignore next */
-                : create_array(buffer);
-        })(buffer);
-    }
-    /* istanbul ignore next */
-    : create_array;
+Reader.create = create();
 
 Reader.prototype._slice = util.Array.prototype.subarray || /* istanbul ignore next */ util.Array.prototype.slice;
 
@@ -377,6 +381,8 @@ Reader.prototype.skipType = function(wireType) {
 
 Reader._configure = function(BufferReader_) {
     BufferReader = BufferReader_;
+    Reader.create = create();
+    BufferReader._configure();
 
     var fn = util.Long ? "toLong" : /* istanbul ignore next */ "toNumber";
     util.merge(Reader.prototype, {

src/reader_buffer.js

@@ -24,16 +24,21 @@ function BufferReader(buffer) {
      */
 }
 
-/* istanbul ignore else */
-if (util.Buffer)
-    BufferReader.prototype._slice = util.Buffer.prototype.slice;
+BufferReader._configure = function () {
+    /* istanbul ignore else */
+    if (util.Buffer)
+        BufferReader.prototype._slice = util.Buffer.prototype.slice;
+};
+
 
 /**
  * @override
  */
 BufferReader.prototype.string = function read_string_buffer() {
     var len = this.uint32(); // modifies pos
-    return this.buf.utf8Slice(this.pos, this.pos = Math.min(this.pos + len, this.len));
+    return this.buf.utf8Slice
+        ? this.buf.utf8Slice(this.pos, this.pos = Math.min(this.pos + len, this.len))
+        : this.buf.toString('utf-8', this.pos, this.pos = Math.min(this.pos + len, this.len))
 };
 
 /**
@@ -42,3 +47,5 @@ BufferReader.prototype.string = function read_string_buffer() {
  * @function
  * @returns {Buffer} Value read
  */
+
+BufferReader._configure();

src/writer.js

@@ -121,21 +121,25 @@ function Writer() {
     // part is just a linked list walk calling operations with already prepared values.
 }
 
+var create = function create() {
+    return util.Buffer
+        ? function create_buffer_setup() {
+            return (Writer.create = function create_buffer() {
+                return new BufferWriter();
+            })();
+        }
+        /* istanbul ignore next */
+        : function create_array() {
+            return new Writer();
+        };
+};
+
 /**
  * Creates a new writer.
  * @function
  * @returns {BufferWriter|Writer} A {@link BufferWriter} when Buffers are supported, otherwise a {@link Writer}
  */
-Writer.create = util.Buffer
-    ? function create_buffer_setup() {
-        return (Writer.create = function create_buffer() {
-            return new BufferWriter();
-        })();
-    }
-    /* istanbul ignore next */
-    : function create_array() {
-        return new Writer();
-    };
+Writer.create = create();
 
 /**
  * Allocates a buffer of the specified size.
@@ -456,4 +460,6 @@ Writer.prototype.finish = function finish() {
 
 Writer._configure = function(BufferWriter_) {
     BufferWriter = BufferWriter_;
+    Writer.create = create();
+    BufferWriter._configure();
 };

src/writer_buffer.js

@@ -7,8 +7,6 @@ var Writer = require("./writer");
 
 var util = require("./util/minimal");
 
-var Buffer = util.Buffer;
-
 /**
  * Constructs a new buffer writer instance.
  * @classdesc Wire format writer using node buffers.
@@ -19,27 +17,28 @@ function BufferWriter() {
     Writer.call(this);
 }
 
-/**
- * Allocates a buffer of the specified size.
- * @param {number} size Buffer size
- * @returns {Buffer} Buffer
- */
-BufferWriter.alloc = function alloc_buffer(size) {
-    return (BufferWriter.alloc = util._Buffer_allocUnsafe)(size);
-};
+BufferWriter._configure = function () {
+    /**
+     * Allocates a buffer of the specified size.
+     * @param {number} size Buffer size
+     * @returns {Buffer} Buffer
+     */
+    BufferWriter.alloc = util._Buffer_allocUnsafe;
 
-var writeBytesBuffer = Buffer && Buffer.prototype instanceof Uint8Array && Buffer.prototype.set.name === "set"
-    ? function writeBytesBuffer_set(val, buf, pos) {
-        buf.set(val, pos); // faster than copy (requires node >= 4 where Buffers extend Uint8Array and set is properly inherited)
-                           // also works for plain array values
-    }
-    /* istanbul ignore next */
-    : function writeBytesBuffer_copy(val, buf, pos) {
-        if (val.copy) // Buffer values
+    BufferWriter.writeBytesBuffer = util.Buffer && util.Buffer.prototype instanceof Uint8Array && util.Buffer.prototype.set.name === "set"
+        ? function writeBytesBuffer_set(val, buf, pos) {
+          buf.set(val, pos); // faster than copy (requires node >= 4 where Buffers extend Uint8Array and set is properly inherited)
+          // also works for plain array values
+        }
+        /* istanbul ignore next */
+        : function writeBytesBuffer_copy(val, buf, pos) {
+          if (val.copy) // Buffer values
             val.copy(buf, pos, 0, val.length);
-        else for (var i = 0; i < val.length;) // plain array values
+          else for (var i = 0; i < val.length;) // plain array values
             buf[pos++] = val[i++];
-    };
+        };
+};
+
 
 /**
  * @override
@@ -50,22 +49,22 @@ BufferWriter.prototype.bytes = function write_bytes_buffer(value) {
     var len = value.length >>> 0;
     this.uint32(len);
     if (len)
-        this._push(writeBytesBuffer, len, value);
+        this._push(BufferWriter.writeBytesBuffer, len, value);
     return this;
 };
 
 function writeStringBuffer(val, buf, pos) {
     if (val.length < 40) // plain js is faster for short strings (probably due to redundant assertions)
         util.utf8.write(val, buf, pos);
     else
-        buf.utf8Write(val, pos);
+        buf.utf8Write ? buf.utf8Write(val, pos) : buf.write(val, pos);
 }
 
 /**
  * @override
  */
 BufferWriter.prototype.string = function write_string_buffer(value) {
-    var len = Buffer.byteLength(value);
+    var len = util.Buffer.byteLength(value);
     this.uint32(len);
     if (len)
         this._push(writeStringBuffer, len, value);
@@ -79,3 +78,5 @@ BufferWriter.prototype.string = function write_string_buffer(value) {
  * @function
  * @returns {Buffer} Finished buffer
  */
+
+BufferWriter._configure();

tests/comp_bytes.js

@@ -0,0 +1,89 @@
+var tape = require("tape");
+
+var protobuf = require("..");
+
+var oldBufferImpl = Buffer.alloc === undefined;
+
+// extends Buffer
+(CustomBuffer.prototype = Object.create(Buffer.prototype)).constructor = CustomBuffer;
+
+function CustomBuffer(arg, encodingOrOffset, length) {
+    Buffer.call(this, arg, encodingOrOffset, length);
+    CustomBuffer.toCustom(this);
+}
+
+CustomBuffer.isBuffer = Buffer.isBuffer.bind(Buffer);
+
+CustomBuffer.toCustom = function (b) {
+    b._isCustom = true;
+    return b;
+}
+
+CustomBuffer.isCustom = function (b) {
+    return !!b._isCustom;
+}
+
+CustomBuffer.from = function (valueOf, encodingOrOffset, length) {
+    return CustomBuffer.toCustom(oldBufferImpl
+        ?  new Buffer(valueOf, encodingOrOffset, length)
+        : Buffer.from(valueOf, encodingOrOffset, length)
+    );
+}
+
+CustomBuffer.alloc = function (size, fill, encoding) {
+    return CustomBuffer.toCustom(oldBufferImpl
+        ?  new Buffer(size, fill, encoding)
+        : Buffer.alloc(size, fill, encoding)
+    );
+}
+
+CustomBuffer.allocUnsafe = function (size) {
+    return CustomBuffer.toCustom(oldBufferImpl
+        ?  new Buffer(size)
+        : Buffer.allocUnsafe(size)
+    );
+}
+
+CustomBuffer.prototype.slice = function (start, end) {
+    return CustomBuffer.toCustom(this.slice(start, end));
+}
+
+tape.test("configure a custom encoder/decoder for bytes", function(test) {
+    var oldBuffer = protobuf.util.Buffer;
+
+    protobuf.util.Buffer = CustomBuffer;
+    protobuf.configure();
+
+    var root = protobuf.Root.fromJSON({
+        nested: {
+            test: {
+                nested: {
+                    Test: {
+                        fields: {
+                            data: {
+                                type: "bytes",
+                                id: 1
+                            }
+                        }
+                    }
+                }
+            }
+        }
+    });
+
+    var Test = root.lookup("test.Test");
+
+    var buffer = Test.encode({
+        data: CustomBuffer.from('some-data')
+    }).finish();
+    test.ok(CustomBuffer.isCustom(buffer), "should encode the message with a custom buffer");
+
+    var decoded = Test.decode(buffer);
+    test.ok(CustomBuffer.isCustom(decoded.data), "should decode `data` into a custom buffer");
+
+    protobuf.util.Buffer = oldBuffer;
+    protobuf.configure();
+
+    test.end();
+
+});