Vim Configuration for LSST Development

This page will help you configure Vim to be consistent with LSST’s coding standards and development practices.

C++ filetype configuration

The following configuration file should be placed in ~/.vim/ftplugin/c.vim:

setlocal shiftwidth=4
setlocal softtabstop=4
setlocal expandtab
setlocal textwidth=110
setlocal cino=:0,l1,g0,(0,u0,W2s
setlocal comments^=s2:/**,mb:*,ex:*/
syntax match cTodo /\todo/

You may also need to tell vim to indent according to your filetype plugins by adding the following to ~/.vimrc:

filetype plugin indent on

Explanation

setlocal shiftwidth=4

Sets the autoindent spacing to 4 spaces. setlocal to limit this to the current (C++) buffer.

setlocal softtabstop=4

Sets the spacing for tab characters to 4 spaces.

setlocal expandtab

Always use spaces; never use tab characters.

setlocal textwidth=110

Limit the length of a line to 110 characters (see 4-6 of the C++ Style Guide)

setlocal cino=:0,l1,g0,(0,u0,W2s

Set the C indent configuration.

• :0: align case labels with the enclosing switch.
• l1: indent statements relative to the case label, not anything following.
• g0: align C++ scope (private/public) labels with the enclosing class.
• (0: align lines after “(foo” next to the unclosed parenthesis.
• u0: same as above for the next level of parentheses deeper.
• W2s: indent lines following a line-terminating unclosed parenthesis by two shiftwidths (8 spaces).

setlocal comments^=s2:/**,mb:*,ex:*/

Allow comments to start with two asterisks for Doxygen.

syntax match cTodo /\todo/

Highlights lines using the Doxygen \todo.

Clang-format integration

There is an integration for Vim which lets you run the clang-format standalone tool on your current buffer, optionally selecting regions to reformat. The integration has the form of a python-file which can be found under clang/tools/clang-format/clang-format.py.

This can be integrated by adding the following to your .vimrc:

map <C-K> :pyf <path-to-this-file>/clang-format.py<cr>
imap <C-K> <c-o>:pyf <path-to-this-file>/clang-format.py<cr>

The first line enables clang-format for NORMAL and VISUAL mode, the second line adds support for INSERT mode. Change C-K to another binding if you need clang-format on a different key (C-K stands for Ctrl+k).

With this integration you can press the bound key and clang-format will format the current line in NORMAL and INSERT mode or the selected region in VISUAL mode. The line or region is extended to the next bigger syntactic entity.

It operates on the current, potentially unsaved buffer and does not create or save any files. To revert a formatting, just undo.