Evaluate custom equality testers before any others.

spec/suites/EnvSpec.js

@@ -65,4 +65,77 @@ describe("jasmine.Env", function() {
       expect(fakeReporter.log).wasCalledWith("message");
     });
   });
+
+  describe("equality testing", function() {
+    describe("with custom equality testers", function() {
+      var aObj, bObj, isEqual;
+
+      beforeEach(function() {
+        env.addEqualityTester(function(a, b) {
+          aObj = a;
+          bObj = b;
+          return isEqual;
+        });
+      });
+
+      it("should call the custom equality tester with two objects for comparison", function() {
+        env.equals_("1", "2");
+        expect(aObj).toEqual("1");
+        expect(bObj).toEqual("2");
+      });
+
+      describe("when the custom equality tester returns false", function() {
+        beforeEach(function() {
+          isEqual = false;
+        });
+
+        it("should give custom equality testers precedence", function() {
+          expect(env.equals_('abc', 'abc')).toBeFalsy();
+          var o = new Object();
+          expect(env.equals_(o, o)).toBeFalsy();
+        });
+      });
+
+
+      describe("when the custom equality tester returns true", function() {
+        beforeEach(function() {
+          isEqual = true;
+        });
+
+        it("should give custom equality testers precedence", function() {
+          expect(env.equals_('abc', 'def')).toBeTruthy();
+          expect(env.equals_(true, false)).toBeTruthy();
+        });
+      });
+
+      describe("when the custom equality tester returns undefined", function() {
+        beforeEach(function() {
+          isEqual = jasmine.undefined;
+        });
+
+        it("should use normal equality rules", function() {
+          expect(env.equals_('abc', 'abc')).toBeTruthy();
+          expect(env.equals_('abc', 'def')).toBeFalsy();
+        });
+
+        describe("even if there are several", function() {
+          beforeEach(function() {
+            env.addEqualityTester(function(a, b) { return jasmine.undefined; });
+            env.addEqualityTester(function(a, b) { return jasmine.undefined; });
+          });
+
+          it("should use normal equality rules", function() {
+            expect(env.equals_('abc', 'abc')).toBeTruthy();
+            expect(env.equals_('abc', 'def')).toBeFalsy();
+          });
+        });
+      });
+
+      it("should evaluate custom equality testers in the order they are declared", function() {
+        isEqual = false;
+        env.addEqualityTester(function(a, b) { return true; });
+        expect(env.equals_('abc', 'abc')).toBeFalsy();
+      });
+    });
+  });
 });