text diagram for git conflicts

conflicts.md

              master
                |
                |
   +-------<----+----->------+
   |            |            |
   |            |            |
   |            |            |
branch1         |         branch2
   |            |            |
   |            |            |
   +----->------|            |
                |            |
                |            |
                X-conflict-<-+

Rebase conflicts Assume we start like this where A, B, C etc represents staged changes.

             master
section1        |
   C-------<----A
   |            |         section2
   D            B +----->----F
   |                         |
   E                         G

             master
                |
                A
                |         
                B
                |         rebase-back-to-master
                C------->----C
                |            |
                F            D
                             |
                             E

if rebase rebase-back-to-master into master we get

             master
                |
                A
                |         
                B
                |         rebase-back-to-master
                C------->----C
                |            |
                D            D
                |            |
                E            E
                |
                F

if just plain merge we get

             master
                |
                A
                |         
                B
                |         rebase-back-to-master
                C------>-----C
                |            |
                F            D
                |            |
                G------<-----E
                
where G is like a knot that ties up both branches

remedy is perform 1. pull and rebase at rebase-back-to-master and then 2. resolve conflict at rebase-back-to-master

             master
                |
                A
                |         
                B
                |         rebase-back-to-master
                C------->----C
                |            |
                F            F' 
                             |
                             D
                             |
                             E

After we merge section1 back to master

             master
section1        |
   C-------<----A
   |            |         section2
   D            B +----->----F
   |            |            |
   E            D'           G
                |            
                E'
   

Note!! When you perform a git rebase operation, you're typically moving commits around. So if section1 branch and section2 branch changed same files with respect to the same lines, github pull request will stop you to merge section2 into master branch with rebase since there are conflicts.