update signal test to use vitest expectTypeOf

[santoshyadavdev]

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• The commit message follows our guidelines: https://github.com/ngrx/platform/blob/main/CONTRIBUTING.md#commit
• Tests for the changes have been added (for bug fixes / features)
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PR Type

What kind of change does this PR introduce?

[ ] Bugfix
[ ] Feature
[ ] Code style update (formatting, local variables)
[x] Refactoring (no functional changes, no api changes)
[ ] Build related changes
[ ] CI related changes
[ ] Documentation content changes
[ ] Other... Please describe:

What is the current behavior?

Closes #

What is the new behavior?

uses expectTypeOf for type testing, this closed #4935 partially

Does this PR introduce a breaking change?

[ ] Yes
[ ] No

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[timdeschryver]

Why is this in a callback function?

[santoshyadavdev]

Ohh no leftover, I will replace it, I thought I already did

[santoshyadavdev]

@timdeschryver i think we need arrow function, earlier these calls were string so no actual call was happening, but If i dont wrap it around arrow function, ts will execute addNumber and it will always throw exception as its not an array, let me know if there is some clean way to do this

[rainerhahnekamp]

@santoshyadavdev. Looks reasonable to me at first sight. Still have to check it thoroughly, but it seems we will settle down with a combination of @ts-expect-error and Vitest type assertions?

[santoshyadavdev]

@santoshyadavdev. Looks reasonable to me at first sight. Still have to check it thoroughly, but it seems we will settle down with a combination of @ts-expect-error and Vitest type assertions?

Yes you are right, I will fix some pending code and linter soon

[mrazauskas]

Do I get it right that pnpm exec nx test signals should run the updated tests? Hm.. I tried adding obviously failing line (like const a: number = "abc") to modules/signals/spec/types/signal-state.types.spec.ts. Running the command reports all tests passing. Or did I misunderstood something?

@rainerhahnekamp Would be be still interested to check out TSTyche? (Based on #4935 (comment)). I could put together a similar PR. One of the advantages, there would be no need for @ts-expect-error directives, that cast too wide a net (in type testing context). Because any errors in the following line are suppressed.