--- title: Referencing other commits in commit messages date: 2024-05-20 permalink: daily/2024/05/20/referencing-other-commits-in-commit-messages tags: - software-development - git cta: ~ snippet: | Have you tried referencing other commits when writing a commit message? --- Last week, I asked [whether you should include issue IDs in commit messages][0]. Another thing I like to reference in a commit message is the commit ID (or SHA) of a related commit. For example, when I run `git log` in my website repository, I see commits like this: ```plain commit 0c91825c16217d0fe7eff4ea100a67550051c4a9 Author: Oliver Davies Date: Sat May 11 15:32:07 2024 +0200 Create a cached talk counter Create a cached version of the talk counter service that returns a cached result of the talk count for that day. This uses the Decorator design pattern to decorate the existing `TalkCounter` service and works as they both implement the same `TalkCounterInterface`. ``` The sha for this commit is `0c91825c16217d0fe7eff4ea100a67550051c4a9`. If I was to make another commit that was related to this one, I can include this commit sha in my new commit message. I also don't need to include the entire thing - only enough for it to be unique (usually five or six characters). Once pushed, the commit IDs should never change, so this will be a permanent reference to the first commit. Helpfully, websites like GitHub, GitLab and Bitbucket will identify it as a commit sha and make it clickable so you can easily navigate to the referenced commit. [0]: {{site.url}}/daily/2024/05/15/should-you-include-issue-ids-in-your-commit-messages