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How to prevent many git conflicts when rebasing many commits?

Story: in the middle of a project my colleague created a new branch from master and started doing her heavy re-factoring work. I created my branch from master and started doing new stuff on the page. We are committing regularly, but only I can rebase code to master (because colleagues changes are too heavy and cannot be deployed from master yet). Unfortunately some of our work rely on the same files. So after few days of work when she finally wanted to rebase her changes to master, she had a lot of git conflicts. 

my_branch    #---#----#-#-------#----#--#-----#---#----#----#
            /     \              \   \   \              \    \
master     *-------*--------------*---*---*--------------*----*----*
            \                                                     /
her branch   #------#-------#-----------#-----------#------------#

Question 1 is: how to prevent lot of git conflicts when we are working on same files? (or what is the best practice in this situation?)

but this isn't the end of our question, ...to be absolutely correct she tried to do rebase from master to her branch (to have changes I committed), so the commit map should look something like this 

my_branch    #---#----#-#-------#----#--#-----#---#----#----#
            /     \              \   \   \              \    \
master     *-------*--------------*---*---*--------------*----*----*
            \                   \            \                    /
her branch   #------#-------#----*------#-----*-----#------------#

And this is what is bothering us. During these rebases she was fixing those conflicts. But git doesn't remember her decision on conflict fix, so when she did another git rebase from master to her-branch she had to fix the same git conflicts again that she was fixing in previous rebases.

Question 2 is: how to tell git to remember git conflict fix after git rebase from master branch, so after next rebase we don't have to fix the same conflicts again?

Solution

  • Fortunately, git has a mechanism for dealing with exactly this problem called git rerere - essentially, if you have git rerere enabled, then each time your resolve a conflict the fact that you resolved that exact conflict in a particular way is remembered. If the same conflict comes up again, the same resolution is automatically used. There are some helpful articles below:

    ... but essentially you can just do:

    git config --global rerere.enabled 1

    ... and forget about it, while enjoying easier rebasing / merging :)