Added a jasmine.exactly asymmetric equality tester

spec/core/SuiteSpec.js

@@ -71,20 +71,9 @@ describe('Suite', function() {
     suite.beforeAll(outerBefore);
     suite.beforeAll(innerBefore);
 
-    function sameInstance(expected) {
-      return {
-        asymmetricMatch: function(actual) {
-          return actual === expected;
-        },
-        jasmineToString: function() {
-          return `<same instance as ${expected}>`;
-        }
-      };
-    }
-
     expect(suite.beforeAllFns).toEqual([
-      { fn: outerBefore.fn, type: 'beforeAll', suite: sameInstance(suite) },
-      { fn: innerBefore.fn, type: 'beforeAll', suite: sameInstance(suite) }
+      { fn: outerBefore.fn, type: 'beforeAll', suite: jasmine.exactly(suite) },
+      { fn: innerBefore.fn, type: 'beforeAll', suite: jasmine.exactly(suite) }
     ]);
   });
 

spec/core/asymmetric_equality/ExactlySpec.js

@@ -0,0 +1,30 @@
+describe('Exactly', function() {
+  it('passes for primitives that are ===', function() {
+    const exactly = new jasmineUnderTest.Exactly(17);
+    expect(exactly.asymmetricMatch(17)).toBeTrue();
+  });
+
+  it('fails for primitives that are not ===', function() {
+    const exactly = new jasmineUnderTest.Exactly(42);
+    expect(exactly.asymmetricMatch('42')).toBeFalse();
+  });
+
+  it('passes for the same object instance', function() {
+    const obj = {};
+    const exactly = new jasmineUnderTest.Exactly(obj);
+    expect(exactly.asymmetricMatch(obj)).toBeTrue();
+  });
+
+  it('fails for different object instances, even if they are deep value equal', function() {
+    const exactly = new jasmineUnderTest.Exactly({});
+    expect(exactly.asymmetricMatch({})).toBeFalse();
+  });
+
+  it('describes itself for use in diffs and pretty printing', function() {
+    const exactly = new jasmineUnderTest.Exactly({ foo: ['bar'] });
+    const pp = jasmineUnderTest.basicPrettyPrinter_;
+    expect(exactly.jasmineToString(pp)).toEqual(
+      "<jasmine.exactly(Object({ foo: [ 'bar' ] }))>"
+    );
+  });
+});