Font Lock Profiler is coverage and time measurement tool for font-lock developers.

You can measure the time it takes to highlight a buffer or a region. Alternatively, you can start the measurement, edit the buffer, and stop.

The result is presented in a table, which can be sorted. Initially, a summary of each keyword is presented. The table can be expanded so that each individual part (like matcher or face expression) can be inspected.

Getting the package

The Font Lock Profiler package is located on Github.