Today I discovered the git cherry command which lets you view the commits from one branch which have not been picked into another.
Using it is pretty simple:
git checkout my-branch
git cherry <upstream> <head>
Where <upstream> is the base branch, and <head> is the branch containing the additional commits.
Lets see a small example. Create a new directory, and inside it create a new git repo. We will also create an empty file, and commit it:
mkdir cherry-test && cd cherry-test
git init
touch file.txt
git add file.txt
git commit -m "First commit"
Now that we have a commit, let's create a new branch off master:
git branch develop
This develop branch will now have the single commit ("First commit" from above). Still on master, lets create another file, and commit that too:
touch another_file.txt
git add another_file.txt
git commit -m "Second commit"
This leaves us in the place where we have a commit on master, which has not yet been cherry-picked onto our "develop" branch. Now, if we checkout the develop branch (git checkout develop), we can use git cherry to view the commits which we can cherry-pick (in our case, just the one):
git cherry develop master
This will show all the commits we have not yet cherry-picked from master into develop. The output is something like:
$ git cherry develop master
+ 722610c62760255e587bc8fec91b917550f38e77
Notice the + at the start. This indicates that the commit has not yet been cherry-picked. If we were to cherry-pick this commit and re-run git cherry as above, we would see the same ID prefixed with - instead of + indicating that the commit has been cherry-picked already.
Viewing commit IDs on their own doesn't give us a whole lot of information. We can add the -v option to git cherry to include the subject of each commit in the output:
$ git cherry develop master
+ 722610c62760255e587bc8fec91b917550f38e77 Second commit
Now we can see our message "Second commit" from earlier is displayed alongside the ID. From here we can use git show to view more information about any particular commit in the list.
You can run man git-cherry to read more about this command. It's super useful, and I wish I knew about it before now!