fix(core): detecting self-references in mocks #5262

help-me-mom · Mar 25, 2023 · c699d57 · c699d57
1 parent 12b6147
commit c699d57
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Showing 5 changed files with 155 additions and 41 deletions.
diff --git a/libs/ng-mocks/src/lib/mock-service/helper.replace-with-mocks.ts b/libs/ng-mocks/src/lib/mock-service/helper.replace-with-mocks.ts
@@ -18,16 +18,17 @@ const handleSection = (section: any[]) => {
   return guards;
 };
 
-const handleArray = (value: any[], callback: any): [boolean, any[]] => {
-  const mock = [];
+const handleArray = (cache: Map<any, any>, value: any[], callback: any): [boolean, any[]] => {
+  const mock: Array<any> = [];
   let updated = false;
+  cache.set(value, mock);
 
   for (const valueItem of value) {
     if (ngMocksUniverse.isExcludedDef(valueItem)) {
       updated = updated || true;
       continue;
     }
-    mock.push(callback(valueItem));
+    mock.push(callback(valueItem, cache));
     updated = updated || mock[mock.length - 1] !== valueItem;
   }
 
@@ -38,16 +39,21 @@ const handleItemKeys = ['canActivate', 'canActivateChild', 'canDeactivate', 'can
 const handleItemGetGuards = (mock: any, section: string) =>
   Array.isArray(mock[section]) ? handleSection(mock[section]) : mock[section];
 
-const handleItem = (value: Record<keyof any, any>, callback: any): [boolean, Record<keyof any, any>] => {
+const handleItem = (
+  cache: Map<any, any>,
+  value: Record<keyof any, any>,
+  callback: any,
+): [boolean, Record<keyof any, any>] => {
   let mock: Record<keyof any, any> = {};
   let updated = false;
+  cache.set(value, mock);
 
   for (const key of Object.keys(value)) {
     if (ngMocksUniverse.isExcludedDef(value[key])) {
       updated = updated || true;
       continue;
     }
-    mock[key] = callback(value[key]);
+    mock[key] = callback(value[key], cache);
     updated = updated || mock[key] !== value[key];
   }
 
@@ -63,21 +69,24 @@ const handleItem = (value: Record<keyof any, any>, callback: any): [boolean, Rec
   return [updated, mock];
 };
 
-const replaceWithMocks = (value: any): any => {
+const replaceWithMocks = (value: any, cache: Map<any, any>): any => {
   if (ngMocksUniverse.cacheDeclarations.has(value)) {
     return ngMocksUniverse.cacheDeclarations.get(value);
   }
   if (typeof value !== 'object') {
     return value;
   }
+  if (cache.has(value)) {
+    return value;
+  }
 
   let mock: any;
   let updated = false;
 
   if (Array.isArray(value)) {
-    [updated, mock] = handleArray(value, replaceWithMocks);
+    [updated, mock] = handleArray(cache, value, replaceWithMocks);
   } else if (value) {
-    [updated, mock] = handleItem(value, replaceWithMocks);
+    [updated, mock] = handleItem(cache, value, replaceWithMocks);
   }
 
   if (updated) {
@@ -89,4 +98,12 @@ const replaceWithMocks = (value: any): any => {
   return value;
 };
 
-export default (() => replaceWithMocks)();
+const replaceWithMocksWrapper = (value: any) => {
+  const cache = new Map();
+  const result = replaceWithMocks(value, cache);
+  cache.clear();
+
+  return result;
+};
+
+export default (() => replaceWithMocksWrapper)();
diff --git a/libs/ng-mocks/src/lib/mock-service/mock-service.ts b/libs/ng-mocks/src/lib/mock-service/mock-service.ts
@@ -7,21 +7,35 @@ import checkIsFunc from './check.is-func';
 import checkIsInst from './check.is-inst';
 import helperMockService from './helper.mock-service';
 
-const mockVariableMap: Array<
-  [(def: any) => boolean, (service: any, prefix: string, callback: typeof MockService) => any]
-> = [
-  [checkIsClass, (service: any) => helperMockService.createMockFromPrototype(service.prototype)],
+type MockServiceHandler = (cache: Map<any, any>, service: any, prefix?: string, overrides?: any) => any;
+
+const mockVariableMap: Array<[(def: any) => boolean, MockServiceHandler]> = [
+  [
+    checkIsClass,
+    (cache, service) => {
+      const value = helperMockService.createMockFromPrototype(service.prototype);
+      cache.set(service, value);
+
+      return value;
+    },
+  ],
   [
     checkIsFunc,
-    (service: any, prefix: string) => helperMockService.mockFunction(`func:${prefix || funcGetName(service)}`),
+    (cache, service, prefix) => {
+      const value = helperMockService.mockFunction(`func:${prefix || funcGetName(service)}`);
+      cache.set(service, value());
+
+      return value;
+    },
   ],
   [def => Array.isArray(def), () => []],
   [
     checkIsInst,
-    (service, prefix, callback) => {
+    (cache, service, prefix, callback) => {
       const value = helperMockService.createMockFromPrototype(service.constructor.prototype);
+      cache.set(service, value);
       for (const property of Object.keys(service)) {
-        const mock: any = callback(service[property], `${prefix || 'instance'}.${property}`);
+        const mock: any = callback(cache, service[property], `${prefix || 'instance'}.${property}`);
         if (mock !== undefined) {
           value[property] = mock;
         }
@@ -33,14 +47,27 @@ const mockVariableMap: Array<
   ],
 ];
 
-const mockVariable = (service: any, prefix: string, callback: typeof MockService) => {
+const mockVariable = (cache: Map<any, any>, service: any, prefix: string, callback: MockServiceHandler) => {
   for (const [check, createMock] of mockVariableMap) {
     if (!check(service)) {
       continue;
     }
 
-    return createMock(service, prefix, callback);
+    return cache.get(service) ?? createMock(cache, service, prefix, callback);
+  }
+};
+
+/**
+ * Mocking all methods / properties of a class / object.
+ */
+const mockService: MockServiceHandler = (cache, service, prefix = '', overrides): any => {
+  const value: any = mockVariable(cache, service, prefix, mockService);
+
+  if (overrides) {
+    mockHelperStub(value, overrides);
   }
+
+  return value;
 };
 
 /**
@@ -53,52 +80,48 @@ export function MockService(service: boolean | number | string | null | undefine
 
 /**
  * MockService creates a mock instance out of an object or a class.
- * The second parameter can be used as overrides.
  *
  * @see https://ng-mocks.sudo.eu/api/MockService
  *
  * ```ts
- * const service = MockService(AuthService, {
- *   loggedIn: true,
- * });
+ * const service = MockService(AuthService);
  * service.login(); // does nothing, it's dummy.
- * ```
  */
-export function MockService<T>(service: AnyType<T>, overrides?: Partial<T>, mockNamePrefix?: string): T;
+export function MockService<T>(service: AnyType<T>, spyNamePrefix?: string): T;
 
 /**
  * MockService creates a mock instance out of an object or a class.
  *
  * @see https://ng-mocks.sudo.eu/api/MockService
  *
  * ```ts
- * const service = MockService(AuthService);
- * service.login(); // does nothing, it's dummy.
+ * const mockUser = MockService(currentUser);
+ * mockUser.save(); // does nothing, it's dummy.
  */
-export function MockService<T>(service: AnyType<T>, mockNamePrefix?: string): T;
+export function MockService<T = any>(service: object, spyNamePrefix?: string): T;
 
 /**
  * MockService creates a mock instance out of an object or a class.
+ * The second parameter can be used as overrides.
  *
  * @see https://ng-mocks.sudo.eu/api/MockService
  *
  * ```ts
- * const mockUser = MockService(currentUser);
- * mockUser.save(); // does nothing, it's dummy.
+ * const service = MockService(AuthService, {
+ *   loggedIn: true,
+ * });
+ * service.login(); // does nothing, it's dummy.
+ * ```
  */
-export function MockService<T = any>(service: object, mockNamePrefix?: string): T;
+export function MockService<T>(service: AnyType<T>, overrides?: Partial<T>, spyNamePrefix?: string): T;
 
 export function MockService(service: any, ...args: any[]): any {
-  // mocking all methods / properties of a class / object.
-
-  const mockNamePrefix = args.length > 0 && typeof args[0] === 'string' ? args[0] : args[1];
+  const prefix = args.length > 0 && typeof args[0] === 'string' ? args[0] : args[1];
   const overrides = args.length > 0 && args[0] && typeof args[0] === 'object' ? args[0] : undefined;
 
-  const value: any = mockVariable(service, mockNamePrefix, MockService);
+  const cache = new Map();
+  const result = mockService(cache, service, prefix, overrides);
+  cache.clear();
 
-  if (overrides) {
-    mockHelperStub(value, overrides);
-  }
-
-  return value;
+  return result;
 }
diff --git a/tests-failures/mock-service.ts b/tests-failures/mock-service.ts
@@ -12,8 +12,22 @@ class Service {
   }
 }
 
-MockService(TOKEN);
-MockService(Service);
+const token = MockService(TOKEN);
+const service = MockService(Service);
+
+// token is any, so it can be whatever
+const tokenCheck1: undefined = token;
+// token is any, so it can be  whatever
+const tokenCheck2: Service = token;
+// token is any, so it can be  whatever
+const tokenCheck3: number = token;
+
+// @ts-expect-error: Service is not undefined
+const serviceCheck1: undefined = service;
+// service is Service
+const serviceCheck2: Service = service;
+// @ts-expect-error: Service is not number
+const serviceCheck3: number = service;
 
 // @ts-expect-error: does not accept wrong types.
 MockService(Service, {

diff --git a/tests/issue-5262/test.spec.ts b/tests/issue-5262/test.spec.ts
@@ -0,0 +1,46 @@
+import { InjectionToken, NgModule, VERSION } from '@angular/core';
+
+import { MockBuilder, MockRender } from 'ng-mocks';
+
+const TOKEN = new InjectionToken('TOKEN');
+
+@NgModule({
+  providers: [
+    {
+      provide: TOKEN,
+      useValue: (() => {
+        const recursive: any = {
+          index: 0,
+        };
+        // It fails without ivy on the compiler level.
+        if (Number.parseInt(VERSION.major, 10) >= 13) {
+          recursive.parent = recursive;
+        }
+
+        return recursive;
+      })(),
+    },
+  ],
+})
+class TargetModule {}
+
+// @see https://github.com/help-me-mom/ng-mocks/issues/5262
+describe('issue-5262', () => {
+  describe('mock', () => {
+    beforeEach(() => MockBuilder(null, TargetModule));
+
+    it('does not fail on recursion', () => {
+      const token = MockRender(TOKEN);
+      expect(token).toBeDefined();
+    });
+  });
+
+  describe('keep', () => {
+    beforeEach(() => MockBuilder(TOKEN, TargetModule));
+
+    it('does not fail on recursion', () => {
+      const token = MockRender(TOKEN);
+      expect(token).toBeDefined();
+    });
+  });
+});
diff --git a/tests/mock-service/test.spec.ts b/tests/mock-service/test.spec.ts
@@ -13,4 +13,18 @@ describe('mock-service', () => {
     );
     expect(instance.echo1()).toBeUndefined();
   });
+
+  it('adds prefixes', () => {
+    const instance = MockService(
+      class {
+        private readonly value = 'unnamed';
+
+        public echo1() {
+          return this.value;
+        }
+      },
+      'prefix',
+    );
+    expect(instance.echo1()).toBeUndefined();
+  });
 });