Merge strategies overview in Git - Practice Problems & Coding Challenges

Challenge - 5 Problems

🧠 Conceptual

intermediate

Understanding Git Merge Strategies

Which Git merge strategy creates a new commit when fast-forward is not possible?

A ours

B resolve

C octopus

D recursive

💡 Hint

Think about the default strategy Git uses for two-parent merges that preserves history.

The recursive strategy is the default for merging two branches and creates a merge commit when a fast-forward is not possible. Other strategies behave differently.

💻 Command Output

intermediate

Output of a Fast-Forward Merge

What is the output of the following Git command sequence?

git checkout main
git merge feature-branch

Assuming main is behind feature-branch and no conflicts exist.

A

Updating abc123..def456
Fast-forward

B Merge made by recursive.

C Automatic merge failed; fix conflicts and then commit the result.

D Already up to date.

💡 Hint

Consider what happens when the current branch can be moved forward without creating a merge commit.

A fast-forward merge moves the branch pointer forward without a merge commit, showing 'Fast-forward' in the output.

❓ Configuration

advanced

Configuring Git to Always Use the 'Ours' Merge Strategy

Which Git configuration command sets the default merge strategy to ours for all merges?

A git config --global merge.default ours

B git config --global merge.default-strategy ours

C git config --global merge.strategy ours

D git config --global merge.strategy.default ours

💡 Hint

Look for the correct Git config key for setting the merge strategy.

The correct key to set the default merge strategy is merge.strategy. Setting it to ours makes Git use that strategy by default.

❓ Troubleshoot

advanced

Troubleshooting a Failed Octopus Merge

You attempt to merge three branches at once using the octopus strategy but get an error. What is the most likely cause?

A There are conflicts between at least two branches.

B The octopus strategy only supports merging two branches.

C The branches have diverged too much for any merge.

D The repository is in a detached HEAD state.

💡 Hint

Octopus merges multiple branches but has limitations.

The octopus strategy can merge multiple branches but fails if there are conflicts. It does not handle conflicts well.

🔀 Workflow

expert

Choosing the Correct Merge Strategy for a Complex Workflow

You have a long-running feature branch and want to keep its history linear on the main branch but still incorporate upstream changes regularly. Which Git merge strategy and workflow combination best fits this need?

A Use 'git merge -s ours' to ignore upstream changes and keep feature branch history.

B Use 'git rebase' on the feature branch regularly before merging with fast-forward.

C Use 'git merge --no-ff' to create merge commits preserving history.

D Use 'git merge --squash' to combine all changes into one commit on main.

💡 Hint

Think about keeping a clean, linear history while incorporating upstream changes.

Rebasing the feature branch onto main regularly keeps history linear and up to date. Then merging with fast-forward avoids extra merge commits.