test: implement tests for jestjs#1214

phra · Dec 25, 2017 · a4a6313 · a4a6313
1 parent 65d884d
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diff --git a/packages/jest-mock/src/__tests__/jest_mock.test.js b/packages/jest-mock/src/__tests__/jest_mock.test.js
@@ -666,4 +666,96 @@ describe('moduleMocker', () => {
       expect(spy2.mock.calls.length).toBe(1);
     });
   });
+
+  describe('spyOnProperty', () => {
+    it('should work', () => {
+      let isOriginalCalled = false;
+      let originalCallThis;
+      let originalCallArguments;
+      const obj = {
+        get method() {
+          return function () {
+            isOriginalCalled = true;
+            originalCallThis = this;
+            originalCallArguments = arguments;
+          }
+        },
+      };
+
+      const spy = moduleMocker.spyOnProperty(obj, 'method');
+
+      const thisArg = {this: true};
+      const firstArg = {first: true};
+      const secondArg = {second: true};
+      obj.method.call(thisArg, firstArg, secondArg);
+      expect(isOriginalCalled).toBe(true);
+      expect(originalCallThis).toBe(thisArg);
+      expect(originalCallArguments.length).toBe(2);
+      expect(originalCallArguments[0]).toBe(firstArg);
+      expect(originalCallArguments[1]).toBe(secondArg);
+      expect(spy).toHaveBeenCalled();
+
+      isOriginalCalled = false;
+      originalCallThis = null;
+      originalCallArguments = null;
+      spy.mockReset();
+      spy.mockRestore();
+      console.log('porcoddddddiooo', obj, obj.method)
+      obj.method.call(thisArg, firstArg, secondArg);
+      expect(isOriginalCalled).toBe(true);
+      expect(originalCallThis).toBe(thisArg);
+      expect(originalCallArguments.length).toBe(2);
+      expect(originalCallArguments[0]).toBe(firstArg);
+      expect(originalCallArguments[1]).toBe(secondArg);
+      expect(spy).not.toHaveBeenCalled();
+    });
+
+    it('should throw on invalid input', () => {
+      expect(() => {
+        moduleMocker.spyOnProperty(null, 'method');
+      }).toThrow();
+      expect(() => {
+        moduleMocker.spyOnProperty({}, 'method');
+      }).toThrow();
+      expect(() => {
+        moduleMocker.spyOnProperty({method: 10}, 'method');
+      }).toThrow();
+    });
+
+    it('supports restoring all spies', () => {
+      let methodOneCalls = 0;
+      let methodTwoCalls = 0;
+      const obj = {
+        get methodOne() {
+          return function () {methodOneCalls++};
+        },
+        get methodTwo() {
+          return function () {methodTwoCalls++};
+        },
+      };
+
+      const spy1 = moduleMocker.spyOnProperty(obj, 'methodOne');
+      const spy2 = moduleMocker.spyOnProperty(obj, 'methodTwo');
+
+      // First, we call with the spies: both spies and both original functions
+      // should be called.
+      obj.methodOne();
+      obj.methodTwo();
+      expect(methodOneCalls).toBe(1);
+      expect(methodTwoCalls).toBe(1);
+      expect(spy1.mock.calls.length).toBe(1);
+      expect(spy2.mock.calls.length).toBe(1);
+
+      moduleMocker.restoreAllMocks();
+
+      // Then, after resetting all mocks, we call methods again. Only the real
+      // methods should bump their count, not the spies.
+      obj.methodOne();
+      obj.methodTwo();
+      expect(methodOneCalls).toBe(2);
+      expect(methodTwoCalls).toBe(2);
+      expect(spy1.mock.calls.length).toBe(1);
+      expect(spy2.mock.calls.length).toBe(1);
+    });
+  });
 });
diff --git a/packages/jest-mock/src/index.js b/packages/jest-mock/src/index.js
@@ -739,13 +739,15 @@ class ModuleMockerClass {
 
       descriptor[accessType] = this._makeComponent({type: 'function'}, () => {
         descriptor[accessType] = original;
+        Object.defineProperty(obj, propertyName, descriptor)
       });
 
       descriptor[accessType].mockImplementation(function() {
         return original.apply(this, arguments);
       });
     }
 
+    Object.defineProperty(obj, propertyName, descriptor)
     return descriptor[accessType];
   }
 

diff --git a/packages/jest-runtime/src/__tests__/runtime_jest_spy_on.test.js b/packages/jest-runtime/src/__tests__/runtime_jest_spy_on.test.js
@@ -35,4 +35,25 @@ describe('Runtime', () => {
         expect(spy).toHaveBeenCalled();
       }));
   });
+
+  describe('jest.spyOnProperty', () => {
+    it('calls the original function', () =>
+      createRuntime(__filename).then(runtime => {
+        const root = runtime.requireModule(runtime.__mockRootPath);
+
+        let isOriginalCalled = false;
+        const obj = {
+          get method() {
+            return () => isOriginalCalled = true;
+          },
+        };
+
+        const spy = root.jest.spyOnProperty(obj, 'method');
+
+        obj.method();
+
+        expect(isOriginalCalled).toBe(true);
+        expect(spy).toHaveBeenCalled();
+      }));
+  });
 });