Using overrideComponent breaks code coverage when testing with aot: true

[cexbrayat]

Command

test

Is this a regression?

• [ ] Yes, this behavior used to work in the previous version

The previous version in which this bug was not present was

No response

Description

When using TestBed.overrideComponent to stub a child component, the test code coverage is no longer accurate

Minimal Reproduction

Generate a new app with latest CLI and add a component:

npx @angular/[email protected] new aot-coverage --defaults --no-routing
cd aot-coverage
ng g c user

Use app-user in app.html:

<h1>Hello, aot-coverage</h1>
<app-user></app-user>

Edit angular.json to add "aot": true in the test section and run:

ng test --no-watch --code-coverage

Coverage is 100%

Statements   : 100% ( 12/12 )
Branches     : 100% ( 11/11 )
Functions    : 100% ( 3/3 )
Lines        : 100% ( 6/6 )

Now, in the app.spec.ts, add in beforeEach:

TestBed.overrideComponent(App, {
  remove: {
    imports: [User],
  },
  add: {
    imports: [User],
  }
});

(this happens with a proper stub of course but even removing the import and adding it back works to reproduce the issue)

Run the tests again:

ng test --no-watch --code-coverage

Coverage is now inaccurate because the template is not properly covered:

Statements   : 58.33% ( 7/12 )
Branches     : 90.9% ( 10/11 )
Functions    : 66.66% ( 2/3 )
Lines        : 66.66% ( 4/6 )

Exception or Error

Your Environment

Angular CLI: 20.0.0-next.6
Node: 22.14.0
Package Manager: npm 10.9.0
OS: darwin arm64

Angular: 20.0.0-next.7
... common, compiler, compiler-cli, core, forms
... platform-browser, router

Package                      Version
------------------------------------------------------
@angular-devkit/architect    0.2000.0-next.6
@angular-devkit/core         20.0.0-next.6
@angular-devkit/schematics   20.0.0-next.6
@angular/build               20.0.0-next.6
@angular/cli                 20.0.0-next.6
@schematics/angular          20.0.0-next.6
rxjs                         7.8.2
typescript                   5.8.3
zone.js                      0.15.0

Anything else relevant?

No response

[cexbrayat]

Interestingly, this is the case with the karma builder or the unit-test builder with karma as a runner, but not with vitest as a runner as it currently does not include templates in the coverage report.