I read this post and realised I had been writing unhelpfully terse commit messages for many years. I went down a rabbit hole and discovered you can have a template commit message which you manually customise for each commit. I got some tips on configuring vim from this article. Then I wondered if it was possible to populate the template dynamically. I found this answer but didn’t have time to get my head around the vim scripting, so I decided to do it myself in bash.
Requirements
- Template file for git commit messages
- Auto-filled with Jira issue number, scraped from the branch name
- Automatically word-wrapped and spell-checked by my text editor
- Available from both zsh and bash
Files
~/.git-commit-template.orig
ISSUE Title
Body~/.vimrc
filetype on
colorscheme industry
autocmd FileType gitcommit set textwidth=72 colorcolumn=+1 colorcolumn+=51 spell~/.bash_profile
source ~/.zshrc~/.zshrc
export EDITOR=/usr/bin/vim
alias gc='ISSUE=$(git branch --show-current | grep -oE "DF-[0-9]+"); sed "s,ISSUE,$ISSUE,g" ~/.git-commit-template.orig > ~/.git-commit-template; git commit'Configuration
I ran the following commands.
# Setup git to use template
cp ~/.git-commit-template.orig ~/.git-commit-template
git config --global commit.template ~/.git-commit-template
# Make the original read-only
chmod 0440 ~/.git-commit-template.origUsage
To commit, I type gc and vim opens with the pre-filled template. On saving and quitting vim, the commit is made.
How it works
The gc alias gets the current branch with
git branch --show-currentand extracts the Jira issue number using the regular expression "DF-[0-9]+". The letters at the start are the Jira project code. If you have more than one Jira project, you probably have to make a different alias for each one.
It then reads the original read-only template file, replaces the word ISSUE with the issue number, and writes the output to the actual file that git uses for the commit template. Finally, it starts a new commit.
Because it is an alias, you can append any additional arguments you need to supply to the git commit command. For example, gc --amend will run git commit amend at the end of the command.
Update April 2023
Git has a built-in feature which enables this functionality – see the prepare-commit-msg hook. The approach I used above is still useful in cases where hooks are being managed team-wide by the repository owner.