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JevMade field notes / Technical guide

Select tests from a Git change

jev-test-filter asks which tests a code change may affect. It always includes changed tests, includes uncertain cases, and can fall back to running everything when selective testing is unsupported.

Original by mizchiEvaluation

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Credits and license

“jev-test-filter” by mizchi. Read the original source.

This expanded guide is an AI-narrated adaptation of the source’s essential explanation, examples and caveats, not a word-for-word reading. The synthetic voice does not imitate the author or imply their endorsement.

License: MIT

MIT License

Copyright (c) 2026 mizchi

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Our summary

A code project may have many automated tests, making every small edit slow to check. jev-test-filter compares a Git change with the tests known to the normal test runner. It suggests which tests to run, without replacing the testing framework itself.

Tests directly changed by the edit run without a model decision. Uncertain selections also run. Detailed output records each score and selection reason, while separate outcomes distinguish no selected tests from bad input or failure. Unsupported situations can use a full test run instead.

A selected set is not proof that all affected behaviour is covered. Missing context may hide a relevant test, so keep the full suite for release checks. The guide also warns that copying its generated command arguments incorrectly can change how they are interpreted.

Key takeaways

  1. Always include tests directly changed by the edit.
  2. Run uncertain cases rather than skipping them.
  3. Keep full testing for releases and unsupported changes.

The repository's example selection is source-reported. JevMade did not execute its supported test runners.

GitHub README · Source reviewed

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