Squashing commits in Git - Practice Problems & Coding Challenges

Challenge - 5 Problems

💻 Command Output

intermediate

What is the output of this git command sequence?

You have 3 commits on your branch. You run git rebase -i HEAD~3 and squash the last two commits into one. What will git log --oneline show after completing the rebase?

Git

commit1: Initial commit
commit2: Added feature A
commit3: Fixed bug in feature A

A One commit with message of commit3 only

B Two commits: first commit unchanged, second commit combines commit2 and commit3

C One commit with combined message of all three commits

D Three separate commits unchanged

💡 Hint

Squashing merges commits into the previous one, combining their changes and messages.

Squashing the last two commits into one means the first commit stays, and the second and third commits merge into one. So the log shows two commits: the original first commit and a combined commit of the last two.

❓ Troubleshoot

intermediate

Why does git rebase -i HEAD~3 fail with 'cannot rebase: You have unstaged changes'?

You try to squash commits using git rebase -i HEAD~3 but get an error about unstaged changes. What is the cause?

A Your repository is corrupted and needs repair

B You are on the wrong branch and must switch to master first

C You have uncommitted changes in your working directory that must be committed or stashed before rebasing

D You need to update git to the latest version

💡 Hint

Git requires a clean working directory to safely rebase.

Git prevents rebasing when there are unstaged or uncommitted changes to avoid conflicts or data loss. You must commit or stash changes before rebasing.

❓ Configuration

advanced

How to configure git to always use squash when merging a feature branch?

You want to set up your git repository so that when you merge a feature branch into main, it always squashes commits automatically. Which configuration achieves this?

A git config --global merge.squash true

B git config --global pull.rebase squash

C git config --global merge.ff false

D git config --global merge.squash false

💡 Hint

Look for a setting related to merge and squash.

Setting merge.squash to true makes git merge commands squash commits by default.

🔀 Workflow

advanced

What is the correct sequence to squash the last 4 commits into one with a new message?

You want to combine the last 4 commits into a single commit with a new commit message. Which sequence of commands is correct?

A git rebase -i HEAD~4; mark first commit as 'pick' and others as 'squash'; save and exit

B git rebase -i HEAD~4; mark all commits as 'pick'; save and exit

C git merge --squash HEAD~4; git commit -m "New combined message"

D git reset --soft HEAD~4; git commit -m "New combined message"

💡 Hint

Interactive rebase lets you choose which commits to squash.

In interactive rebase, you keep the first commit as 'pick' and mark the rest as 'squash' to combine them into one commit with a new message.

✅ Best Practice

expert

What is the best practice when squashing commits before pushing to a shared remote branch?

You have squashed multiple commits locally and want to push to a shared remote branch. What should you do to avoid disrupting others?

A Force push with <code>git push --force</code> after squashing

B Push normally with <code>git push</code> without force

C Delete the remote branch and push again

D Create a new branch and push the squashed commits there

💡 Hint

Force pushing can overwrite others' work.

Force pushing to a shared branch can overwrite others' commits and cause problems. Creating a new branch preserves history and avoids conflicts.