InvocationMirror implemented in dart2js.

tests/language/invocation_mirror_test.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.
+
+// Test direct use of InvocationMirror.invokeOn and Function.apply in
+// noSuchMethod.
+
+class PlusMinus {
+  noSuchMethod(InvocationMirror invocation) {
+    if (invocation.memberName == 'mul') {
+      return invocation.invokeOn(mulObject);
+    } else if (invocation.memberName == 'div') {

[bakster, 2012/10/24 13:43:04]

Inconsistent use of else parts. I suggest:
   if (bla) return foo;
   if (bla) return bar;
   return rest;

[Johnni Winther, 2012/10/25 13:34:56]

Done.

+      return invocation.invokeOn(divObject);
+    }
+    return Function.apply(plus,
+                          invocation.positionalArguments,
+                          invocation.namedArguments);
+  }
+
+  int plus(int a, int b) => a+b;
+
+  Mul get mulObject => new Mul();
+
+  Div get divObject => new Div();
+}
+
+class Mul {
+  int mul(int a, int b, [int c]) {
+    if (?c) {

[bakster, 2012/10/24 13:43:04]

Remove else parts

[Johnni Winther, 2012/10/25 13:34:56]

Done.

+      return a*b*c;
+    } else {
+      return a*b;
+    }
+  }
+}
+
+class Div {
+  int div({int num, int denom}) {

[bakster, 2012/10/24 13:43:04]

Use => for short hand function syntax.

[Johnni Winther, 2012/10/25 13:34:56]

Done.

+    return num/denom;
+  }
+}
+
+void main() {
+  var pm = new PlusMinus();
+  Expect.equals(7, pm.plus(2, 5));
+  Expect.equals(5, pm.minus(2, 3)); // Calls plus.
+  Expect.equals(6, pm.mul(2, 3));
+  Expect.equals(24, pm.mul(2, 3, 4));
+  Expect.equals(5, pm.div(num:10, denom:2));
+  Expect.equals(5, pm.div(denom:2, num:10));
+}