fix(core): better eval code to extend es6 classes #5465

libs/ng-mocks/src/lib/common/core.helpers.ts

@@ -114,27 +114,31 @@ export const extractDependency = (deps: any[], set?: Set<any>): void => {
 
 export const extendClassicClass = <I>(base: AnyType<I>): Type<I> => {
   let child: any;
+  const index = ngMocksUniverse.index();
+
   const glb = funcGetGlobal();
+  glb.ngMocksParent = base;
 
   // First we try to eval es2015 style and if it fails to use es5 transpilation in the catch block.
   // The next step is to respect constructor parameters as the parent class via jitReflector.
-  glb.ngMocksParent = base;
   // istanbul ignore next
   try {
     eval(`
       var glb = typeof window === 'undefined' ? global : window;
-      class MockMiddleware extends glb.ngMocksParent {}
-      glb.ngMocksResult = MockMiddleware
+      class MockMiddleware${index} extends glb.ngMocksParent {};
+      glb.ngMocksResult = MockMiddleware${index};
     `);
     child = glb.ngMocksResult;
   } catch {
     class MockMiddleware extends glb.ngMocksParent {}
     child = MockMiddleware;
+  } finally {
+    glb.ngMocksResult = undefined;
+    glb.ngMocksParent = undefined;
   }
-  glb.ngMocksParent = undefined;
 
   // A16: adding unique property.
-  coreDefineProperty(child.prototype, `__ngMocks_index_${ngMocksUniverse.index()}`, undefined, false);
+  coreDefineProperty(child.prototype, `__ngMocks_index_${index}`, undefined, false);
 
   return child;
 };

tests/issue-5465/test.spec.ts

@@ -0,0 +1,62 @@
+import { NgForOf } from '@angular/common';
+import { Component, NgModule, VERSION } from '@angular/core';
+
+import { MockBuilder, MockRender } from 'ng-mocks';
+
+// @see https://github.com/help-me-mom/ng-mocks/issues/5465
+// TypeError: Class constructor CommonModule cannot be invoked without 'new'
+describe('issue-5465', () => {
+  if (Number.parseInt(VERSION.major, 10) < 14) {
+    it('needs a14', () => {
+      // pending('Need Angular 14+');
+      expect(true).toBeTruthy();
+    });
+
+    return;
+  }
+
+  @Component({
+    selector: 'app-ng-for',
+    template: `
+      <span *ngFor="let letter of this.test">{{ letter }}</span>
+    `,
+  })
+  class AppNgForComponent {
+    test = ['a', 'b'];
+
+    appNgFor5465() {}
+  }
+
+  @NgModule({
+    imports: [
+      NgForOf as never /* TODO: remove after upgrade to a14 */,
+    ],
+    declarations: [AppNgForComponent],
+    exports: [AppNgForComponent],
+  })
+  class AppNgForModule {}
+
+  @Component({
+    selector: 'app-root',
+    template: ` <app-ng-for></app-ng-for> `,
+  })
+  class AppRootComponent {
+    appRoot5465() {}
+  }
+
+  @NgModule({
+    declarations: [AppRootComponent],
+    imports: [AppNgForModule],
+    providers: [],
+    bootstrap: [AppRootComponent],
+  })
+  class AppModule {}
+
+  beforeEach(() =>
+    MockBuilder([AppRootComponent], [AppModule, NgForOf]),
+  );
+
+  it('renders AppRootComponent', () => {
+    expect(() => MockRender(AppRootComponent)).not.toThrow();
+  });
+});