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Ivy TestBed should throw descriptive errors when override methods are used with incompatible types

See original GitHub issue

🐞 bug report

Affected Package

The issue is caused by package "@angular/core": "9.0.0-rc.3",

Description

When I use TestBed.overrideComponent to override some services with their mocks, the tests start failing with the following error:

 Cannot read property 'templateUrl' of null

The code snippet that’s causing the error:

TestBed.overrideComponent(SomeDirective, {
      set: { providers: [{ provide: SomeService, useClass: MockSomeService }] },
});

🔬 Minimal Reproduction

https://github.com/Shijir/shiny-ivy-app-test-fail

🔥 Exception or Error

Failed: Uncaught (in promise): TypeError: Cannot read property 'templateUrl' of null
TypeError: Cannot read property 'templateUrl' of null
    at componentNeedsResolution (http://localhost:9876/_karma_webpack_/node_modules/@angular/core/__ivy_ngcc__/fesm2015/core.js:21097:1)
    at maybeQueueResolutionOfComponentResources (http://localhost:9876/_karma_webpack_/node_modules/@angular/core/__ivy_ngcc__/fesm2015/core.js:21080:1)
    at compileComponent (http://localhost:9876/_karma_webpack_/node_modules/@angular/core/__ivy_ngcc__/fesm2015/core.js:39395:1)
    at http://localhost:9876/_karma_webpack_/node_modules/@angular/core/__ivy_ngcc__/fesm2015/testing.js:1941:30
    at Set.forEach (<anonymous>)
    at R3TestBedCompiler.compileTypesSync (http://localhost:9876/_karma_webpack_/node_modules/@angular/core/__ivy_ngcc__/fesm2015/testing.js:1932:1)
    at R3TestBedCompiler.<anonymous> (http://localhost:9876/_karma_webpack_/node_modules/@angular/core/__ivy_ngcc__/fesm2015/testing.js:1827:1)
    at Generator.next (<anonymous>)
    at http://localhost:9876/_karma_webpack_/node_modules/tslib/tslib.es6.js:73:1
    at new ZoneAwarePromise (http://localhost:9876/_karma_webpack_/node_modules/zone.js/dist/zone-evergreen.js:872:1)

🌍 Your Environment

Angular Version:

@angular/core": "9.0.0-rc.3

Anything else relevant?

Issue Analytics

State:
Created 4 years ago
Comments:5 (4 by maintainers)

Top GitHub Comments

1reaction

AndrewKushnircommented, Nov 27, 2019

@Shijir, thanks for the update. Adding more descriptive error messages for the cases like this one makes sense, I’ll work on a PR to do that. Note: I will also change the title of the ticket to reflect that. Thank you.

0reactions

angular-automatic-lock-bot[bot]commented, Jan 4, 2020

This issue has been automatically locked due to inactivity. Please file a new issue if you are encountering a similar or related problem.

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