Implement InstanceMirror.== in dart2js and InstanceMirror.hashCode in the VM and …

tests/lib/mirrors/equality_test.dart

+// Copyright (c) 2013, 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 test.class_equality_test;
+
+import 'dart:mirrors';
+
+import 'package:expect/expect.dart';
+
+class A<T> {}
+class B extends A<int> {}
+
+class BadEqualityHash {
+  int count = 0;
+  bool operator ==(other) => true;
+  int get hashCode => count++;
+}
+
+checkEquality(List<Map> equivalenceClasses) {
+  for (var equivalenceClass in equivalenceClasses) {
+    equivalenceClass.forEach((name, member) {
+      equivalenceClass.forEach((otherName, otherMember) {
+        // Reflexivity, symmetry and transitivity.
+        Expect.equals(member, 
+                      otherMember,
+                      "$name == $otherName");
+        Expect.equals(member.hashCode,
+                      otherMember.hashCode,
+                      "$name.hashCode == $otherName.hashCode");
+      });
+      for (var otherEquivalenceClass in equivalenceClasses) {
+        if (otherEquivalenceClass == equivalenceClass) continue;
+        otherEquivalenceClass.forEach((otherName, otherMember) {
+          Expect.notEquals(member,
+                           otherMember,
+                           "$name != $otherName");  // Exclusion.
+          // Hash codes may or may not be equal.
+        });
+      }
+    });
+  }
+}
+
+void subroutine() {
+}
+
+main() {
+  LibraryMirror thisLibrary =
+      currentMirrorSystem()
+      .findLibrary(const Symbol('test.class_equality_test'))
+      .single;
+
+  var o1 = new Object();
+  var o2 = new Object();
+
+  var badEqualityHash1 = new BadEqualityHash();
+  var badEqualityHash2 = new BadEqualityHash();
+
+  checkEquality([

[ahe, 2013/08/30 20:40:14]

Could you avoid passing in a list, and instead call checkEquality multiple
times.

I know it is a bit more verbose and tedious, but it really helps when debugging
dart2js output that the stack trace will point you to test that is failing.

[rmacnak, 2013/08/30 21:08:29]

The number of cases is quadratic. Notice I am passing in unique strings to
identify each of these expressions, so that when the test fails you can easily
identify which pair of mirrors is problematic.

[ahe, 2013/08/30 21:11:13]

OK

+    {'reflect(o1)' : reflect(o1),
+     'reflect(o1), again' : reflect(o1)},
+
+    {'reflect(o2)' : reflect(o2),
+     'reflect(o2), again' : reflect(o2)},
+
+    {'reflect(badEqualityHash1)' : reflect(badEqualityHash1),
+     'reflect(badEqualityHash1), again' : reflect(badEqualityHash1)},
+
+    {'reflect(badEqualityHash2)' : reflect(badEqualityHash2),
+     'reflect(badEqualityHash2), again' : reflect(badEqualityHash2)},
+
+    {'reflect(true)' : reflect(true),
+     'reflect(true), again' : reflect(true)},
+
+    {'reflect(false)' : reflect(false),
+     'reflect(false), again' : reflect(false)},
+
+    {'reflect(null)' : reflect(null),
+     'reflect(null), again' : reflect(null)},
+
+    {'reflect(3.5+4.5)' : reflect(3.5+4.5),
+     'reflect(6.5+1.5)' : reflect(6.5+1.5)},
+
+    {'reflect(3+4)' : reflect(3+4),
+     'reflect(6+1)' : reflect(6+1)},
+
+    {'reflect("foo")' : reflect("foo"),
+     'reflect("foo"), again' : reflect("foo")},
+
+//    {'currentMirrorSystem().voidType' : currentMirrorSystem().voidType,
+//     'thisLibrary.functions[#subroutine].returnType' :
+//          thisLibrary.functions[const Symbol('subroutine')].returnType},
+
+    {'currentMirrorSystem().dynamicType' : currentMirrorSystem().dynamicType,
+     'thisLibrary.functions[#main].returnType' :
+          thisLibrary.functions[const Symbol('main')].returnType},
+
+//    {'reflectClass(A)' : reflectClass(A),
+//    'thisLibrary.classes[#A]' : thisLibrary.classes[const Symbol('A')],
+//     'reflect(new A<int>()).type.originalDeclaration' :
+//          reflect(new A<int>()).type.originalDeclaration},
+
+    {'reflectClass(B).superclass' : reflectClass(B).superclass,
+     'reflect(new A<int>()).type' : reflect(new A<int>()).type},
+
+    {'reflectClass(B)' : reflectClass(B),
+     'thisLibrary.classes[#B]' : thisLibrary.classes[const Symbol('B')],
+     'reflect(new B()).type' : reflect(new B()).type},
+
+    {'thisLibrary' : thisLibrary,
+     'reflectClass(A).owner' : reflectClass(A).owner,
+     'reflectClass(B).owner' : reflectClass(B).owner,
+     'reflect(new A()).type.owner' : reflect(new A()).type.owner,
+     'reflect(new A()).type.owner' : reflect(new A()).type.owner},
+  ]);
+}