I created a package that will lint any syntax_test* file for you while working on it, providing immediate feedback using internal ST API.
Due to technical limitations, changing the syntax will most likely not trigger a re-lint of the syntax test file. You might have to make a change to the file to trigger a re-lint instead.
Note: This package is only available to ST builds >=3092.
Note²: This package is based on SublimeLinter and requires it to be installed.
https://packagecontrol.io/packages/SublimeLinter-contrib-sublime-syntax
