Formatting C++ code

Every once in a while I need to recall how clang-format is set up and run on my Ubuntu 16.04 machine. This post is meant to act as a reminder.

If I want to change all the files in my repository to a particular format (I prefer the Mozilla style), I use:

  find . -name "*.cc" -exec clang-format -i -style Mozilla {} \;
  find . -name "*.h" -exec clang-format -i -style Mozilla {} \;

For integration into vim, I create a .vimrc file and add the following into it

  map <C-I> :py3f /path/to/clang-format.py<cr>
  imap <C-I> <c-o> :py3f /path/to/clang-format.py<cr>
  map <C-a> <esc>ggVG<cr>

The first two commands map ctrl-i to clang-format while the third command just maps ctrl-a to “select all the code”.

The clang-format.py file needs to be a Python3 compatible version and can be downloaded from LLVM.

To make sure that the right format is used by vim, you have to create a .clang-format file containing the style options you will use. In my case I use

  clang-format -style=Mozilla -dump-config > .clang-format

You can also watch a talk on various clang tools below.