Merge Conflicts

Understanding Merge Conflicts

A merge conflict occurs when Git cannot automatically reconcile the changes made on two divergent branches. This typically happens when changes are made to the same lines of code in the same files in both branches since their last common ancestor.

Example Workflow

First, list all branches in the repository:

git branch

You are currently on the master branch, so modify the branch_learning.txt file by adding a new line and directly commit this change:

echo "New line from the master branch" >> branch_learning.txt

git commit -a -m "Add a new line specifying the master branch to branch_learning.txt"

Now switch to the feature branch, add a different new line to the branch_learning.txt file, and directly commit this change:

git checkout feature/new-feature

echo "New line from the feature branch" >> branch_learning.txt

git commit -a -m "Add a new line specifying the feature branch to branch_learning.txt"

Both commits are successful, so switch back to the master branch and merge the feature branch with it:

git checkout master

git merge feature/new-feature

Oops, a merge conflict occurred because the same line in the same file differs between branches, and Git cannot automatically resolve it.

Let's also run the git status command to get more information about the conflict:

git status

This message indicates that you must either abort the merge or fix the conflicts and commit the changes afterward. You’ll proceed with the latter option and resolve the conflicts in the next chapter.