How to Resolve Git Merge Conflicts — A Practical Guide

Merge conflicts are inevitable in collaborative development. Here's a practical guide to understanding, resolving, and preventing them.

What Causes Merge Conflicts?

A merge conflict occurs when Git can't automatically combine changes from two branches because they modify the same lines in the same file differently.

# Common scenario:
# Branch A changes line 10 to: return user.name
# Branch B changes line 10 to: return user.displayName
# Git doesn't know which one to keep → CONFLICT

Reading Conflict Markers

When a conflict occurs, Git inserts markers into the file:

<<<<<<< HEAD
return user.name;
=======
return user.displayName;
>>>>>>> feature-branch

• <<<<<<< HEAD — Your current branch's version
• ======= — Separator between the two versions
• >>>>>>> feature-branch — The incoming branch's version

Resolution Strategies

1. Keep One Side

The simplest resolution — pick either yours or theirs:

git checkout --ours path/to/file    # Keep your version
git checkout --theirs path/to/file  # Keep their version

2. Manual Merge

Often you need elements from both sides. Remove the conflict markers and write the correct combined version:

// Combined resolution:
return user.displayName || user.name;

3. Use a Merge Tool

Visual merge tools make complex conflicts much easier:

git mergetool              # Opens configured merge tool
git config merge.tool vimdiff  # Set default tool

Preventing Conflicts

• Pull frequently: git pull --rebase keeps your branch up to date
• Small PRs: Smaller changes = fewer conflicts
• Communication: Coordinate when multiple people edit the same files
• Feature flags: Merge incomplete features without conflicting

Rebase vs. Merge Conflicts

Rebase replays your commits on top of the target branch one at a time. This means you might resolve the same conflict multiple times, but you get a cleaner history. Merge creates a single merge commit, so you resolve all conflicts at once.

# Rebase approach (cleaner history):
git rebase main
# Resolve each commit's conflicts individually

# Merge approach (single resolution):
git merge main
# Resolve all conflicts at once

Quick Reference

Compare Your Changes

Before committing a resolution, paste both versions into DiffSnap to visually confirm what changed. Use Code Diff for syntax-highlighted comparison.