Carolyn Van Slyck

Set the line endings for all files in a directory

The Git for Windows installer often leads people to turn on AutoCRLF, an occasionally useful feature that can also cause a ton of trouble. Luckily, you aren’t at the mercy of whatever settings a developer may have when contributing to your project. You can force git to do things your way by adding a .gitattributes file to your repository.

This all started when Windows users with AutoCRLF enabled ran the test suite, tests would fail because the files containing expected values were helpfully modified by AutoCRLF to use CRLF instead of LF. It was difficult to troubleshoot because the test’s console output looked fine expected value: foo actual value: foo.

The solution was to setup a .gitattributes file at the root of the repo. This allowed me to override a developer’s AutoCRLF setting and specify that all files in my testdata/ directories should use LF. It can be a bit tricky because patterns which work in .gitignore, like testdata/* don’t work the same when used in .gitattributes.

Here’s the magic pattern to use LF as the line ending for all files in a testdata/ directory, whether at the root of the repo, or nested in subdirectories:

**/testdata/** text eol=lf

The leading ** applies the test pattern at both the root and subdirectories, while the trailing ** ensures that directories nested under testdata/ also match. So this pattern forces LF for the following paths: