How to Combine Git Commits

July 23, 2019 · ~2 minute read

Suppose you have the following commits in your git log:

3a6846f 2019-07-23 Daniel Engbert (HEAD -> master) edited a.txt and b.txt
b98b227 2019-07-23 Daniel Engbert created b.txt
f14e2b4 2019-07-23 Daniel Engbert created a.txt
912bb66 2019-07-23 Daniel Engbert inital commit

If you want to combine the 3 latest commits into one commit like this:

896afa6 2019-07-23 Daniel Engbert (HEAD -> master) created files a.txt and b.txt
912bb66 2019-07-23 Daniel Engbert inital commit

then perform the following:

git pull # (if applicable)
git rebase HEAD~3 --interactive
#git rebase f14e2b4 --interactive   # alternative (does the same thing)

Then edit the file that appears (change the first word in each line from):

# original file (oldest commit is at top)
pick f14e2b4 created a.txt                                                                               
pick b98b227 created b.txt                                                                          
pick 3a6846f edited a.txt and b.txt

to:

# edited file:
# (choose "pick" mode for oldest commit, all other set to "squash")
p f14e2b4 created a.txt                                                                               
s b98b227 created b.txt                                                                          
s 3a6846f edited a.txt and b.txt

Then save the file. A new file will open, replace its contents with whatever message you want for the combined commit and save. Your selected commits should now be combined into one.
Note: if an error is reported after saving the first file, your options are:

# edit the file again to fix the error
git rebase --edit-todo
git rebase --continue

# or abort from the rebase, restoring things to how they were
git rebase --abort

Another Example:

Sometimes you may want to combine some older commits (without combining with more recent ones). For example:

before: c0 -> c1 -> c2 -> c3 (HEAD)

git rebase HEAD~3 -i

# now just update file to look like:
pick c1
squash c2
pick c3

after: c0 -> c1c2 -> c3 (HEAD)