How do I get git to display the changes in vim as hg does with the hgeditor script?

Question

An interesting feature in mercurial is the ability to view the changes that will be committed in a vim split (see DiffsInCommitMessageInVIM).

Any hint on how to do so wi

Answer 1

Assuming you've got syntax enabled, Vim detects git commit messages as a filetype. This should be obvious from highlighting. The much less obvious part is that it also has a filetype plugin for git commits (and other git things). Make sure you have those enabled (filetype plugin on), and then there will be a helpful command defined: DiffGitCached. Just run that, and it'll toss a diff into a preview window.

A comment next to the definition of that command in the plugin:

Automatically diffing can be done with:

autocmd FileType gitcommit DiffGitCached | wincmd p

The filetype plugins are stored in /vimXX/ftplugin/git*.vim, e.g. /usr/share/vim/vim70/ftplugin/gitcommit.vim, if you're curious to have a look!