Intercepting Writes to Files with BufWritePost

Sometimes you find yourself frequently running the same command whenever you save a file. Maybe it’s restarting a local web server, running a build script, or checking your code with a linter. This can be scripted quite easily with BufWritePost command. The basic usage is:

autocmd BufWritePost *.ext call methodName()

This is used in lots of scripts. jshint.vim uses it to invoke a linter, and HgCi will make a commit in Mercurial whenever a file changes.

There’s even a newer Git equivalent called YUNOcommit.vim which shows a message with echo and echohl when you haven't committed frequently enough. This plugin is actually quite short and readable, so you can use it as a basis for your own BufWritePost experiments.