npx @angular/[email protected] new ng21.1.5 -s -t --style css --no-ssr --ai-config none
npm i -E -D [email protected] @vitest/[email protected] @vitest/[email protected] playwright

export const greet = 'Hello';

{
  "compilerOptions": {
    "paths": {
      "#/util": ["./src/app/util.ts"]
    }
  }
}

import { greet } from '#/util';
// ...
export class App {
  protected readonly title = signal(greet);
}

import './app';

npx ng test --no-watch --browsers chromium --coverage --coverage-include src/app/**/*.ts

There's logged errors for every file that uses the path alias, which in our project is most of them (e.g. `import { shared } from '#/core';`).


00:02:12 [vite] (client) Pre-transform error: Failed to resolve import "#/util" from "src/app/app.ts". Does the file exist?
  Plugin: vite:import-analysis
  File: C:/Users/foo/repro/src/app/app.ts:3:22
  11 |  import { Component, signal } from "@angular/core";
  12 |  import { RouterOutlet } from "@angular/router";
  13 |  import { greet } from "#/util";
     |                         ^
  14 |  export let App = class {
  15 |    title = signal(greet);

I've tried with `@angular/build` + `@angular/cli` at several versions, including `21.1.x` and `21.2.x`. Downgrading `vitest` to `4.0.8` fixes the issue, but `[email protected]` and `4.1.2` both failed.

----------------------------------------

Angular CLI       : 21.2.5
Angular           : 21.2.6
Node.js           : 25.8.2 (Unsupported)
Package Manager   : npm 11.11.1
Operating System  : win32 x64

┌───────────────────────────┬───────────────────┬───────────────────┐
│ Package                   │ Installed Version │ Requested Version │
├───────────────────────────┼───────────────────┼───────────────────┤
│ @angular/build            │ 21.2.5            │ ^21.1.5           │
│ @angular/cli              │ 21.2.5            │ ^21.1.5           │
│ @angular/common           │ 21.2.6            │ ^21.1.0           │
│ @angular/compiler         │ 21.2.6            │ ^21.1.0           │
│ @angular/compiler-cli     │ 21.2.6            │ ^21.1.0           │
│ @angular/core             │ 21.2.6            │ ^21.1.0           │
│ @angular/forms            │ 21.2.6            │ ^21.1.0           │
│ @angular/platform-browser │ 21.2.6            │ ^21.1.0           │
│ @angular/router           │ 21.2.6            │ ^21.1.0           │
│ rxjs                      │ 7.8.2             │ ~7.8.0            │
│ typescript                │ 5.9.3             │ ~5.9.2            │
│ vitest                    │ 4.1.0             │ 4.1.0             │
└───────────────────────────┴───────────────────┴───────────────────┘