Add default support for .cts and .mts file extensions#22
Open
domarmstrong wants to merge 1 commit intoistanbuljs:masterfrom
Open
Add default support for .cts and .mts file extensions#22domarmstrong wants to merge 1 commit intoistanbuljs:masterfrom
domarmstrong wants to merge 1 commit intoistanbuljs:masterfrom
Conversation
domarmstrong
added a commit
to domarmstrong/jest
that referenced
this pull request
Mar 10, 2026
Istanbul only collects coverage from files listed in 'extension'. It has a [default list](https://github.com/istanbuljs/schema/blob/master/default-extension.js) of `.js, .cjs, .mjs, .ts, .tsx, .jsx`. Any other files are ignored. As babel-jest doesn't provide the extension, or a way to provide it yourself, there is currently no way to collect coverage from .mts, .cts files. I've [proposed adding them to the default Istanbul list](istanbuljs/schema#22). But in the same fashion that Jest removes all exclusions, it could also provide the extension of the file being transformed to allow Istanbul to collect it's coverage. I can't think of a situation where you would want a file transformed by babel, but not to be instrumented that wouldn't already be handled by jests coverage include/exclude config.
domarmstrong
added a commit
to domarmstrong/jest
that referenced
this pull request
Mar 10, 2026
Istanbul only collects coverage from files listed in 'extension'. It has a [default list](https://github.com/istanbuljs/schema/blob/master/default-extension.js) of `.js, .cjs, .mjs, .ts, .tsx, .jsx`. Any other files are ignored. As babel-jest doesn't provide the extension, or a way to provide it yourself, there is currently no way to collect coverage from .mts, .cts files. I've [proposed adding them to the default Istanbul list](istanbuljs/schema#22). But in the same fashion that Jest removes all exclusions, it could also provide the extension of the file being transformed to allow Istanbul to collect it's coverage. I can't think of a situation where you would want a file transformed by babel, but not to be instrumented that wouldn't already be handled by jests coverage include/exclude config.
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
1 participant
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
I ran in to the fact that jest isn't collecting coverage from .mts files when using babel-jest. It appears this already works in Istanbul but the files are currently excluded. Is there any reason to not include them in the default list of file extensions?