Summary

This article covers handling Git merge conflicts by creating conflicts between branches and resolving them. You'll learn to create a conflict by making diverging changes in a new branch (dev) and the master branch. The steps include: initializing a Git repository, creating branches, pushing changes, and simulating a conflict. The resolution process involves comparing branches, understanding conflict markers in the code, and choosing which changes to accept or reject. After resolving the conflict, you'll merge the dev branch into the master branch successfully.

This article presumes you are familiar with fundamental basic knowledge of Git and GitHub, this would include;

• What is Git, GitHub, and it's importance?

• How to Initialize a Git Repo.

• Create and Push Branches.

• And More...

To have a great overview of git, click here

What Are Git Merge Conflicts?

Create And Solve A Merge Conflict.

1. Create Conflict.

To create a conflict, we are going to follow the steps below.

1. Create a folder, add an HTML file, and push it to Git Hub.

Above is a sample of my pushed HTML file to GitHub. It's on the branch master and in the conflict remote GitHub repository with a commit message of chore .

2. Create a new branch from the master branch for this case, it can be called any name, here the dev branch will be used for the new branch.

git checkout -b dev

Creating a new branch off another branch create a new copy with the exact content of the branch being branched off from with a new branch name.

3. Make changes to the HTML document on the new branch (dev) and push the branch plus the changes to Git Hub. Below is dev the git remote branch.

   <h2> added, <h1> got from the master branch after branch off.

You will be alerted of the push event and you can compare, create pull requests, and merge branches.

Click on Compare & Pull Request button to check if the two branches can be merged with no issues.

if we want now to merge the dev branch with it's changes and master branch, the two branches can merge successfully.

We won't be merging the two branches in this article but to merge, click Create pull request and from there you will be able to merge.

Cause Conflict

To cause a conflict, we need to update the master branch so that it's not in the same state as it was when branching off to create a new branch dev and try to merge them.

Let's use the recent files used.

Initial master file before checkout to dev branch (initial state). Html document with a <h1>

dev branch created by checkout off master with initial state and adding a <h2> from dev branch.

Check merge, Merge possible

Update master after creating dev branch

Now master branch has been updated after creating the dev branch.

The initial state of master branch from which the dev branch was created has changed thus the two copies don't match anymore leading to a conflict.

Merging dev and master Branch.

On dev Branch

The dev branch is 1 commit ahead of, 1 commit behind master

Ahead - The dev branch has one commit that is not yet in the master branch. This indicates that there has been a new change or addition in the dev branch that hasn't been merged into master.

Behind - The dev branch is missing one commit that is present in the master branch. This indicates that there has been a change or addition in the master branch that hasn't been merged into dev.

From the screen above click on Contribute and then compare .

Now, a merge between master and dev git branches is not possible. There is an issue / conflict with the two branches.

2. Resolve Conflict.

Click on Create pull request to solve the conflict.

After creating pull request , scroll down to where the conflict notification is shown, and click on Resolve Conflicts .

View of conflict below.

// = comments

// changes from the dev branch
<<<<<<< dev // branch name with conflict
    <h2>Dev Branch Content</h2>
======= // conflict seperator
// new changes from the master branch
    <h2>Master branch changed after creating dev branch</h2>
>>>>>>> master //branch name with conflict

What Next?

To resolve the conflict, we need to accept or reject the code differences presented. We can Accept or Reject changes from any one branch with the conflict or Accept or Reject all changes on conflicting branches.

Removing the <<< , === , >>> indicates a step toward resolving the conflict.

Sample below shows when only dev changes are accepted, the same can be done to accept the new master changes.

 // Accepting only dev changes, ignoring new master changes.
// '<<<', '===', '>>>' with <h2> from updated master are removed
// to accept only dev changes.

<body>
    <h1>Initial Content</h1>

    <h2>Dev Branch Content</h2>

  </body>

Both Changes Accepted

After choosing what to accept or reject by removing the <<< , === , >>> , click on Mark as resolved on the top right and then Commit merge

After resolving the conflict, Merge possible

Thanks, Happy Coding