Re: Proposal: Allow Customization of Git Merge Commit Message Template

From: brian m. carlson <sandals@crustytoothpaste.net>
Date: Dec 5, 2024, 23:16 UTC
Message-ID: <Z1I0XzE6QWlsyZkH@tapette.crustytoothpaste.net>
In-Reply-To: <DM4PR14MB4880061D71993B749F44F2EDA7302@DM4PR14MB4880.namprd14.prod.outlook.com>

On 2024-12-05 at 17:00:56, dangling . wrote:

Show 9 quoted lines

> Proposal:
> Introduce an option (e.g., a configuration setting or CLI flag) that allows users to specify a custom merge commit message template. For example:
> 
> - A new configuration option:
>   ```sh
>   [merge]
>       messageTemplate = "Merge %s into %s"
>   ```
>   Here, `%s` placeholders could represent the source and destination branches, respectively.

I think in general that such an option would need multiple placeholders. Just because in English we place the name of the second head before the name of the first head does not mean that that is true in all languages or translations.

> - Alternatively, a command-line flag:
>   ```sh
>   git merge --message-template="Merge %s into %s" upstream/main
>   ```

I think this can be done more generally with a `prepare-commit-msg` hook:

---- #!/bin/sh

COMMIT_MSG_FILE=$1 COMMIT_SOURCE=$2

case "$COMMIT_SOURCE" in
 merge)
   /usr/bin/perl -i.bak -pe '
   s/Merge remote-tracking branch '\''(.*)'\''/Merge $1/
   ' "$COMMIT_MSG_FILE"
   ;;
 *) ;;
esac
----

That's the approach we would generally recommend here, since it's more flexible and allows you more customization over the message. Of course, you can use sed or Ruby instead (or even ed or ex) if you prefer.

-- 
brian m. carlson (they/them or he/him)
Toronto, Ontario, CA