backstage/.changeset/neat-insects-share.md

@backstage/cli

@backstage/cli
minor

The Jest configuration that was previously enabled with BACKSTAGE_NEXT_TESTS is now enabled by default. To revert to the old configuration you can now instead set BACKSTAGE_OLD_TESTS.

This new configuration uses the babel coverage provider rather than v8. It used to be that v8 worked better when using Sucrase for transpilation, but now that we have switched to SWC, babel seems to work better. In addition, the new configuration also enables source maps by default, as they no longer have a negative impact on code coverage accuracy, and it also enables a modified Jest runtime with additional caching of script objects.