user3693167 user3693167 - 14 days ago 8
Git Question

how does exactly a git merge conflict happen?

I have made a git repository and added a text file to it. This is 100% for learning purpose.


  1. I added "1" to the text file and committed it to master.

  2. Created a new branch from master and appended "2".

  3. Finally, created a branch from master and appended "3".



Could you please explain how a conflict may occur in this, or any other, scenario?

Answer

You will have a conflict if you merge:

  • branch2 to master (no conflict)
  • branch3 to master (conflict):

That is because:

  • The common ancestor would be master (with a second line empty)
  • the source content is branch3 (with a second line including "3")
  • the destination content is on latest of master (with a second line including "2", from the merge of branch2 to master)

Git will ask you to choose which content to keep ("3", "2", or both).

First, do the merges after:

git config merge.conflictstyle diff3

See "Fix merge conflicts in Git?".