Add daily email for 2024-05-20

Referencing other commits in commit messages

source/_daily_emails/2024-05-20.md

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+---
+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 <oliver@oliverdavies.dev>
+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