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[dtslint] Improve failure message when tests fail on one TS version and pass on another

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#644 2 comments 0 reactions 0 assignees View on GitHub

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
45/100
Issue type
Feature
Clarity
Mostly clear
Activity status
Quiet
Tech stack
typescript
Domain
testing, tooling

Research direction

Start by locating dtslint's reporting for tests run across multiple TypeScript versions, then reproduce the ExpectType mismatch with versions 4.9 and 5.0. Done means a failing result clearly states which TypeScript version passed and which failed, while preserving the existing failure details.

Written by the indexing model from the issue text.

Description

Hi,
I've spent the better part of a day chasing an issue where ExpectType would complain about a type mismatch and then would complain again the other way if I changed the expected type. (#632).

Turns out, the two issues were on different TS versions which output generic types differently (4.9 vs 5.0).

It would be nice if there was a bigger warning when tests pass on one TS version and fail on another (it prints the version in the error message, but apparently, that's not enough) - something like "The test PASS on 5.1 but FAIL on 4.9:"

Dominant language
TypeScript
Stars
423
Forks
237
Avg merge
18h 18m
Merged PRs (30d)
11

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  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

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