docs/contribute/bug_fix.md
Fixing a bug begins with a GitHub issue, a new branch, and a failing test. All bug fixes require test coverage. This test can be either a JavaScript test, or it can be a demo page. A lot of our fixes are CSS only fixes, and this can only be verified with a demo page.
If your fix requires a new API, then you'll have to break your PR into two. First create a new PR with a new feature, following this feature workflow. After that PR is merged, then submit the fix PR.
The final commit message for a fix to the mdc-foo package, for GitHub issue 1234, should look like this:
fix(foo): Short description of fix
Resolves #1234
This commit message is pulled into our CHANGELOG when we release and is based on Angular's Git commit guidelines.