Implement Function.prototype.bind (ES5 15.3.4.5)....

test/mjsunit/function-bind.js

Index: test/mjsunit/function-bind.js
===================================================================
--- test/mjsunit/function-bind.js	(revision 0)
+++ test/mjsunit/function-bind.js	(revision 0)
@@ -0,0 +1,184 @@
+// Copyright 2010 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Tests the Function.prototype.bind (ES 15.3.4.5) method.
+
+// Simple tests.
+function foo(x, y, z) {
+  return x + y + z;
+}
+
+var f = foo.bind(foo);
+assertEquals(3, f(1, 1, 1));
+assertEquals(3, f.length);
+
+f = foo.bind(foo, 2);
+assertEquals(4, f(1, 1));
+assertEquals(2, f.length);
+
+f = foo.bind(foo, 2, 2);
+assertEquals(5, f(1));
+assertEquals(1, f.length);
+
+f = foo.bind(foo, 2, 2, 2);
+assertEquals(6, f());
+assertEquals(0, f.length);
+
+// Test that length works correctly even if more than the actual number
+// of arguments are given when binding.
+f = foo.bind(foo, 1, 2, 3, 4, 5, 6, 7, 8, 9);
+assertEquals(6, f());
+assertEquals(0, f.length);
+
+// Use a different bound object.
+var obj = {x: 42, y: 43};
+// Values that would normally be in "this" when calling f_bound_this.
+var x = 42;
+var y = 44;
+
+function f_bound_this(z) {
+  return z + this.y - this.x;
+} 
+
+assertEquals(3, f_bound_this(1))
+f = f_bound_this.bind(obj);
+assertEquals(2, f(1));
+assertEquals(1, f.length);
+
+f = f_bound_this.bind(obj, 2);
+assertEquals(3, f());
+assertEquals(0, f.length);
+
+// Test chained binds.
+
+// When only giving the thisArg, any number of binds should have 
+// the same effect.
+f = foo.bind(foo);
+assertEquals(3, f(1, 1, 1));
+f = foo.bind(foo).bind(foo).bind(foo).bind(foo);
+assertEquals(3, f(1, 1, 1));
+assertEquals(3, f.length);
+
+// Giving bound parameters should work at any place in the chain.
+f = foo.bind(foo, 1).bind(foo).bind(foo).bind(foo);
+assertEquals(3, f(1, 1));
+assertEquals(2, f.length);
+
+f = foo.bind(foo).bind(foo, 1).bind(foo).bind(foo);
+assertEquals(3, f(1, 1));
+assertEquals(2, f.length);
+
+f = foo.bind(foo).bind(foo).bind(foo,1 ).bind(foo);
+assertEquals(3, f(1, 1));
+assertEquals(2, f.length);
+
+f = foo.bind(foo).bind(foo).bind(foo).bind(foo, 1);
+assertEquals(3, f(1, 1));
+assertEquals(2, f.length);
+
+// Several parameters can be given, and given in different bind invokations.
+f = foo.bind(foo, 1, 1).bind(foo).bind(foo).bind(foo);
+assertEquals(3, f(1));
+assertEquals(1, f.length);
+
+f = foo.bind(foo).bind(foo, 1, 1).bind(foo).bind(foo);
+assertEquals(3, f(1));
+assertEquals(1, f.length);
+
+f = foo.bind(foo).bind(foo, 1, 1).bind(foo).bind(foo);
+assertEquals(3, f(1));
+assertEquals(1, f.length);
+
+f = foo.bind(foo).bind(foo).bind(foo, 1, 1).bind(foo);
+assertEquals(3, f(1));
+assertEquals(1, f.length);
+
+f = foo.bind(foo).bind(foo).bind(foo).bind(foo, 1, 1);
+assertEquals(3, f(1));
+assertEquals(1, f.length);
+
+f = foo.bind(foo, 1).bind(foo, 1).bind(foo).bind(foo);
+assertEquals(3, f(1));
+assertEquals(1, f.length);
+
+f = foo.bind(foo, 1).bind(foo).bind(foo, 1).bind(foo);
+assertEquals(3, f(1));
+assertEquals(1, f.length);
+
+f = foo.bind(foo, 1).bind(foo).bind(foo).bind(foo, 1);
+assertEquals(3, f(1));
+assertEquals(1, f.length);
+
+f = foo.bind(foo).bind(foo, 1).bind(foo).bind(foo, 1);
+assertEquals(3, f(1));
+assertEquals(1, f.length);
+
+// Test constructor calls.
+
+function bar(x, y, z) {
+  this.x = x;
+  this.y = y;
+  this.z = z;
+}
+
+f = bar.bind(bar);
+var obj2 = new f(1,2,3);
+assertEquals(1, obj2.x);
+assertEquals(2, obj2.y);
+assertEquals(3, obj2.z);
+
+f = bar.bind(bar, 1);
+obj2 = new f(2,3);
+assertEquals(1, obj2.x);
+assertEquals(2, obj2.y);
+assertEquals(3, obj2.z);
+
+f = bar.bind(bar, 1, 2);
+obj2 = new f(3);
+assertEquals(1, obj2.x);
+assertEquals(2, obj2.y);
+assertEquals(3, obj2.z);
+
+f = bar.bind(bar, 1, 2, 3);
+obj2 = new f();
+assertEquals(1, obj2.x);
+assertEquals(2, obj2.y);
+assertEquals(3, obj2.z);
+
+
+// Test bind chains when used as a constructor.
+
+f = bar.bind(bar, 1).bind(bar, 2).bind(bar, 3);
+obj2 = new f();
+assertEquals(1, obj2.x);
+assertEquals(2, obj2.y);
+assertEquals(3, obj2.z);
+
+// Test instanceof obj2 is bar, not f.
+assertTrue(obj2 instanceof bar);
+assertFalse(obj2 instanceof f);

[Lasse Reichstein, 2010/07/25 11:45:10]

This should be assertTrue too (see ES5, 15.3.4.5.3).

+