Inconsistent merge commit messages

Question

What determines the commit message for a Git merge on SourceTree?

Occasionally I'll get a message indicating a branch merge, occasionally I'll get a message indicating a commit merge -- what triggers the difference, and is there any way to always force the "branch" option?

To be clear -- these are both occurring when trying to commit a separate branch back into master.

Example commit messages:

"Branch" style:

Merge branch 'apc'

"Commit" style:

Merge commit 'd5ba46c6c6275bc272cb29eb09ef28c0bc292578'

stevestreeting · Accepted Answer

SourceTree takes the default commit message for a merge from what Git generates (it puts this in .git/MERGE_MSG) and would normally default to itself if you committed from the command line. We do this for consistency so people get what they'd expect from using the command line version.