How to see commits that were merged in to a merge commit?

git log abc123^..abc123
shows the commits that got merged into merge-commit abc123.

Create a git alias log-merge for easy reuse:

$ git config --global alias.log-merge \
'!f() { git log --stat "$1^..$1"; }; f'
$ git log-merge abc123

For a one-line version:

$ git config --global alias.log-merge-short \
'!f() { git log --pretty=oneline "$1^..$1"; }; f' 

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If you want to see every commits merged in the last merge you can try that :

git log $(git merge-base --octopus \
$(git log -1 --merges --pretty=format:%P)).. --boundary

Here is an example of my current log :

$ git log --graph --pretty=oneline --abbrev-commit
* 44899b9 pouf
*   8f49f9c Merge branch 'test'
|\  
| * 3db39ca test
* | 69f431c pif
* | df1f51c lala
|/  
* 8fae178 pif2
* 20f8ba6 init

If I only want commits related to the last merge I have to use git log -1 --merges --pretty=format:%P which gives me the parents of the first merge available :

$ git log -1 --merges --pretty=format:%P
69f431cec7859b61d33c7503c9431ceea2aaf3e0 3db39ca3ab1e8f70462db23d94590628b5e7ad7b

Now that I know which parents I need to track, I need their common base that I can obtain through git merge-base --octopus (--octopus is there just in case) :

$ git merge-base --octopus \
$(git log -1 --merges \
--pretty=format:%P)
8fae178666e34a480b22e40f858efd9e7c66c3ca

Now with git log I can search every commit since the base to the current HEAD:

$ git log $(git merge-base --octopus \
$(git log -1 --merges --pretty=format:%P)).. \
--boundary --graph --pretty=oneline --abbrev-commit 
* 44899b9 pouf
*   8f49f9c Merge branch 'test'
|\  
| * 3db39ca test
* | 69f431c pif
* | df1f51c lala
|/  
o 8fae178 pif2

If you're a bit perfectionist you can also do this :

$ git log 
$(git merge-base --octopus \
$(git log -1 \
--merges --pretty=format:%P))..$(git log -1 --merges --pretty=format:%H) \
--boundary --graph --pretty=oneline --abbrev-commit 
*   8f49f9c Merge branch 'test'
|\  
| * 3db39ca test
* | 69f431c pif
* | df1f51c lala
|/  
o 8fae178 pif2

Now I think I'll keep this as an alias :)

The --graph --pretty=oneline --abbrev-commit options are optional.

Resources :

Git merge-base

Git log

Git revision

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If you have a merge commit (say a2345) and say git log -1 a2345, it will tell you the names of the parents (i.e. the commits which got merged in this commit). Is that what you're looking for?

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