Add a shortcut for PATCH.

lib/src/client.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library client;
 
 import 'dart:async';
 import 'dart:convert';
 import 'dart:typed_data';
 
 import 'base_client.dart';
 import 'base_request.dart';
 import 'io.dart' as io;
 import 'io_client.dart';
 import 'response.dart';
 import 'streamed_response.dart';
 
 /// The interface for HTTP clients that take care of maintaining persistent
 /// connections across multiple requests to the same server. If you only need to
 /// send a single request, it's usually easier to use [head], [get], [post],
-/// [put], or [delete] instead.
+/// [put], [patch], or [delete] instead.
 ///
 /// When creating an HTTP client class with additional functionality, you must
 /// extend [BaseClient] rather than [Client]. In most cases, you can wrap
 /// another instance of [Client] and add functionality on top of that. This
 /// allows all classes implementing [Client] to be mutually composable.
 abstract class Client {
   /// Creates a new client.
   ///
   /// Currently this will create an [IOClient] if `dart:io` is available and
   /// throw an [UnsupportedError] otherwise. In the future, it will create a
@@ skipping 50 matching lines @@
   /// If [body] is a Map, it's encoded as form fields using [encoding]. The
   /// content-type of the request will be set to
   /// `"application/x-www-form-urlencoded"`; this cannot be overridden.
   ///
   /// [encoding] defaults to [UTF8].
   ///
   /// For more fine-grained control over the request, use [send] instead.
   Future<Response> put(url, {Map<String, String> headers, body,
       Encoding encoding});
 
+  /// Sends an HTTP PATCH request with the given headers and body to the given
+  /// URL, which can be a [Uri] or a [String].
+  ///
+  /// [body] sets the body of the request. It can be a [String], a [List<int>]
+  /// or a [Map<String, String>]. If it's a String, it's encoded using
+  /// [encoding] and used as the body of the request. The content-type of the
+  /// request will default to "text/plain".
+  ///
+  /// If [body] is a List, it's used as a list of bytes for the body of the
+  /// request.
+  ///
+  /// If [body] is a Map, it's encoded as form fields using [encoding]. The
+  /// content-type of the request will be set to
+  /// `"application/x-www-form-urlencoded"`; this cannot be overridden.
+  ///
+  /// [encoding] defaults to [UTF8].
+  ///
+  /// For more fine-grained control over the request, use [send] instead.
+  Future<Response> patch(url, {Map<String, String> headers, body,
+      Encoding encoding});
+
   /// Sends an HTTP DELETE request with the given headers to the given URL,
   /// which can be a [Uri] or a [String].
   ///
   /// For more fine-grained control over the request, use [send] instead.
   Future<Response> delete(url, {Map<String, String> headers});
 
   /// Sends an HTTP GET request with the given headers to the given URL, which
   /// can be a [Uri] or a [String], and returns a Future that completes to the
   /// body of the response as a String.
   ///
@@ skipping 16 matching lines @@
   Future<Uint8List> readBytes(url, {Map<String, String> headers});
 
   /// Sends an HTTP request and asynchronously returns the response.
   Future<StreamedResponse> send(BaseRequest request);
 
   /// Closes the client and cleans up any resources associated with it. It's
   /// important to close each client when it's done being used; failing to do so
   /// can cause the Dart process to hang.
   void close();
 }