FYI Implementing 'super' keyword

test/mjsunit/harmony/super.js

+
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-
+//
 // Flags: --allow-natives-syntax
 
-// Test usage of static type information for loads that would otherwise
-// turn into polymorphic or generic loads.
 
-// Prepare a highly polymorphic load to be used by all tests.
-Object.prototype.load = function() { return this.property; };
-Object.prototype.load.call({ A:0, property:10 });
-Object.prototype.load.call({ A:0, B:0, property:11 });
-Object.prototype.load.call({ A:0, B:0, C:0, property:12 });
-Object.prototype.load.call({ A:0, B:0, C:0, D:0, property:13 });
-Object.prototype.load.call({ A:0, B:0, C:0, D:0, E:0, property:14 });
-Object.prototype.load.call({ A:0, B:0, C:0, D:0, E:0, F:0, property:15 });
+(function() {
+  function Base() { }
+  function Derived() { }
+  Derived.prototype = Object.create(Base.prototype);
 
-// Test for object literals.
-(function() {
-  function f(x) {
-    var object = { property:x };
-    return object.load();
+  function fBase() { return "Base " + this.toString(); }
+  Base.prototype.f = %ToMethod(fBase, Base.prototype);
+  function fDerived() {
+     assertEquals("Base this is Derived", super.f());
+     assertEquals("128 from Base", super[128]());
+     assertEquals("128 from Derived", this[128]());
+     assertEquals(15, super.x);
+     assertEquals(27, this.x);
+     assertEquals(27, super[42]);
+     assertEquals(33, this[42]);
+     super.x = 5;
+     assertEquals(5, Base.prototype.x);
+     assertEquals(5, super.x);
+     assertEquals(27, this.x);
+     super[42] = 6;
+     assertEquals(6, Base.prototype[42]);
+     assertEquals(6, super[42]);
+     assertEquals(33, this[42]);
+
+     return "Derived"
   }
 
-  assertSame(1, f(1));
-  assertSame(2, f(2));
-  %OptimizeFunctionOnNextCall(f);
-  assertSame(3, f(3));
-})();
+  Base.prototype.x = 15;
+  Base.prototype[42] = 27;
+  Base.prototype[128] = function() { return "128 from Base"; }
+  Derived.prototype[128] = function() { return "128 from Derived"; }
+  Base.prototype.toString = function() { return "this is Base"; };
+  Derived.prototype.toString = function() { return "this is Derived"; };
+  Derived.prototype.x = 27;
+  Derived.prototype[42] = 33;
+  Derived.prototype.f = %ToMethod(fDerived, Derived.prototype);
 
-// Test for inlined constructors.
-(function() {
-  function c(x) {
-    this.property = x;
-  }
-  function f(x) {
-    var object = new c(x);
-    return object.load();
-  }
-
-  assertSame(1, f(1));
-  assertSame(2, f(2));
-  %OptimizeFunctionOnNextCall(f);
-  assertSame(3, f(3));
-})();
+  assertEquals("Base this is Base", new Base().f());
+  assertEquals("Derived", new Derived().f());
+}());