This extension provides code snippet for istanbul code coverage library which is also used with jest. The snippets are used to get comments to exclude files or lines from your code coverage.
These are the shortcuts to generate a comment:
/* istanbul ignore <insert_type> reason: <insert_reason> */
/* istanbul ignore next reason: <insert_reason> */
/* istanbul ignore if reason: <insert_reason> */
/* istanbul ignore else reason: <insert_reason> */
Documentation on what these comments do you can find on the offical instanbul documentation.