Vitest: Coverage reporter flagging parenthesis and TS type as uncovered branches

[ChrisMBarr]

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

I am in the process of migrating unit tests from Jasmine to Vitest and I noticed that the code coverage percentages are all being thrown off when using Vitest, which did not happen before with Jasmine.

When I run my tests with coverage, the generated report is flagging things like a closing parentheses or a typescript type as an uncovered code branch. This is happening to me when I use either the v8 or istanbul reporter, it seems to make no difference.

I originally opened an issue with Vitest, but they suggested I open one here

Minimal Reproduction

https://stackblitz.com/edit/angular-eslint-repros-pf1h8ams?file=src%2Fmain.ts,src%2Fapp.component.spec.ts

Exception or Error

• Follow above link
• run npm run test
• Open the code coverage for main.ts
• You will see lines 16 and 17 show uncovered code branches, which affects the coverage percentage. Obviously this is wrong and I would not expect this to happen

Your Environment

Angular CLI       : 21.2.1
Angular           : 21.2.1
Node.js           : 24.12.0
Package Manager   : npm 11.8.0
Operating System  : win32 x64

┌───────────────────────────────────┬───────────────────┬───────────────────┐
│ Package                           │ Installed Version │ Requested Version │
├───────────────────────────────────┼───────────────────┼───────────────────┤
│ @angular/animations               │ 21.2.1            │ ^21.2.1           │
│ @angular/build                    │ 21.2.1            │ ^21.2.1           │
│ @angular/cdk                      │ 21.2.1            │ ~21.2.1           │
│ @angular/cli                      │ 21.2.1            │ ^21.2.1           │
│ @angular/common                   │ 21.2.1            │ ^21.2.1           │
│ @angular/compiler                 │ 21.2.1            │ ^21.2.1           │
│ @angular/compiler-cli             │ 21.2.1            │ ^21.2.1           │
│ @angular/core                     │ 21.2.1            │ ^21.2.1           │
│ @angular/forms                    │ 21.2.1            │ ^21.2.1           │
│ @angular/localize                 │ 21.2.1            │ ^21.2.1           │
│ @angular/platform-browser         │ 21.2.1            │ ^21.2.1           │
│ @angular/platform-browser-dynamic │ 21.2.1            │ ^21.2.1           │
│ @angular/router                   │ 21.2.1            │ ^21.2.1           │
│ vitest                            │ 4.0.18            │ ^4.0.18           │
│ zone.js                           │ 0.16.1            │ ~0.16.1           │
└───────────────────────────────────┴───────────────────┴───────────────────┘

Anything else relevant?

No response

[ChrisMBarr]

As a follow up: updating to 21.2.2 has fixed this issue

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