Webpack Lazy Chunk Error during Component Tests

[laurenzfiala]

I have an Angular service that lazily imports some configuration using webpacks' dynamic import:

import(
  /* webpackMode: "lazy-once" */
  /* webpackPrefetch: true */
  /* webpackChunkName: "locale-configs" */
  `../configs/${locale}`
)
  .then((localeConfigModule: {default: typeof LocaleConfig}) => {
    [...]
  })
  .catch((e) => {
    throw new Error("Couldn't load locale config", {cause: e});
  });

Now, I had to include these configs in tsconfig.app.json, otherwise the files are not part of the compilation:

{
  [...],
  "include": ["src/app/locales/configs/*"]
}

So far, so good. This works as expected.

When I start Cypress Component tests, Angular compiles correctly (just like it does outside of Cypress).
But afterwards I get this error:

asset [...]
chunk [...]
chunk {locale-configs} (runtime: runtime) locale-configs.js (locale-configs) 39 bytes
chunk [...]

ERROR in ./src/app/locales/configs/de.ts
Module build failed (from ./node_modules/@ngtools/webpack/src/ivy/index.js):
Error: C:\Users\xyz\xyz\src\app\locales\configs\de.ts is missing from the TypeScript compilation. Please make sure it is in your tsconfig via the 'files' or 'include' property.
    at C:\Users\xyz\xyz\packages\ngtools\webpack\src\ivy\loader.ts:49:20

2023-10-09 11:46:19: webpack compiled in 3688 ms

It seems that Cypress can't find the original .ts file.

Interestingly, this error does not really do anything (we don't use the locale-configs in the tests). The tests pass anyways.
Unfortunately, our CI sometimes picks this error up and breaks the pipeline.

I checked all kinds of posts, but couldn't find anything related. Does anyone have an idea what could cause this issue?
I'm happy to provide more info or a reproduction if needed.

Version info:
"cypress": "^13.3.0"
"@angular-devkit/build-angular": "~16.2.0"
"@angular/*": "~16.2.0"