BREAKING CHANGE: The testFiles option in config/jest.config.json should now specify the path to compiled CommonJS files, not TypeScript source files. Snapshot resolution depends on the presence of source maps in the output folder.
This release of heft-jest-plugin switched from using Jest's transformer infrastructure and pointing at TypeScript source files to instead directly point Jest at the compiled output files, relying on source maps to redirect snapshot files back to the committed source folder. If no source maps are present, the plugin will assume that the project is authored in raw ECMAScript and expect to find snapshots in a __snapshots__ folder directly alongside the test files.
This release of heft-jest-plugin enabled Jest's clearMocks option by default.
If your project didn't already have this option turned on, it is possible that
previously passing unit tests will fail after the upgrade.
If you do have failing unit tests, then most likely the assertions in the test were incorrect, because the number of calls and call parameters were not being cleared between tests. The ideal solution is to correct these assertions.
If you can't immediately address the failing unit tests, you can turn clearMocks
back off in your config/jest.config.json file:
{
"extends": "@rushstack/heft-jest-plugin/includes/jest-shared.config.json",
"clearMocks": false
}For more information on the clearMocks option, see Jest's clearMocks documentation.