Code review in pull requests in Git - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a pull request in Git?

A pull request is a way to ask team members to review and approve your code changes before merging them into the main project branch.

beginner

Why do we do code reviews in pull requests?

Code reviews help catch mistakes early, improve code quality, share knowledge, and keep the project consistent.

beginner

What should you check during a code review?

Check if the code works as expected, follows style rules, is easy to understand, and does not break anything else.

beginner

How do you leave feedback in a pull request?

You can comment directly on lines of code, suggest changes, or approve the pull request if everything looks good.

beginner

What happens after a pull request is approved?

Once approved, the code changes can be merged into the main branch, making them part of the project.

What is the main purpose of a pull request?

A To review and approve code changes before merging

B To delete old branches

C To create a backup of the repository

D To run automated tests only

A pull request is used to review and approve code changes before merging them into the main branch.

Which of the following is NOT a typical step in a code review?

A Checking code style

B Approving or requesting changes

C Suggesting improvements

D Running the code on a live server without testing

Running code on a live server without testing is risky and not part of a normal code review.

How can you provide feedback on a specific line in a pull request?

A By deleting the pull request

B By commenting directly on that line

C By editing the code yourself without approval

D By sending an email

You can comment directly on specific lines in the pull request to give clear feedback.

What should you do if you find a bug during a code review?

A Delete the pull request

B Ignore it and approve anyway

C Request changes and explain the issue

D Merge the code immediately

You should request changes and explain the problem so the author can fix it.

What happens after a pull request is merged?

A The code becomes part of the main branch

B The code is deleted

C The pull request is reopened automatically

D The repository is archived

Merging a pull request adds the changes to the main branch of the project.

Explain the process and benefits of code review in pull requests.

Think about how teammates check each other's work before adding it to the project.

Describe how you would give constructive feedback during a pull request review.

Imagine helping a friend improve their work kindly and clearly.

Practice

1. What is the main purpose of a pull request in Git?

easy

A. To review and discuss code changes before merging

B. To delete a branch from the repository

C. To create a new repository

D. To reset the main branch to a previous commit

Solution

1. Step 1: Understand what a pull request does

   A pull request is used to propose code changes and get feedback before merging.

2. Step 2: Identify the main purpose

   It allows team members to review, discuss, and approve changes to keep code quality high.

3. Final Answer:

   To review and discuss code changes before merging -> Option A

4. Quick Check:

   Pull request = code review and discussion [OK]

Hint: Pull requests are for reviewing code before merging [OK]

Common Mistakes:

• Confusing pull requests with branch deletion
• Thinking pull requests create repositories
• Believing pull requests reset branches

2. Which Git command is used to push a new branch to the remote repository to start a pull request?

easy

A. git push origin main

B. git merge feature-branch

C. git pull origin feature-branch

D. git push origin feature-branch

Solution

1. Step 1: Identify the command to push a branch

   To push a new branch named 'feature-branch' to remote, use 'git push origin feature-branch'.

2. Step 2: Understand other options

   'git push origin main' pushes the main branch, 'git pull' fetches changes, and 'git merge' combines branches locally.

3. Final Answer:

   git push origin feature-branch -> Option D

4. Quick Check:

   Push new branch = git push origin branch-name [OK]

Hint: Push your feature branch with git push origin branch-name [OK]

Common Mistakes:

• Using git push origin main instead of feature branch
• Confusing git pull with git push
• Trying to merge before pushing the branch

3. Given this sequence of commands, what is the output of git status after step 4?

1. git checkout -b feature
2. touch newfile.txt
3. git add newfile.txt
4. git status

medium

A. On branch feature
Changes to be committed:
(new file: newfile.txt)

B. On branch feature
nothing to commit, working tree clean

C. On branch main
Changes to be committed:
(new file: newfile.txt)

D. fatal: not a git repository

Solution

1. Step 1: Analyze branch and file status

   After 'git checkout -b feature', you are on 'feature' branch. 'touch newfile.txt' creates a new file. 'git add newfile.txt' stages it.

2. Step 2: Understand git status output

   'git status' shows staged changes. Since newfile.txt is added, it appears under 'Changes to be committed' on branch 'feature'.

3. Final Answer:

   On branch feature Changes to be committed: (new file: newfile.txt) -> Option A

4. Quick Check:

   Added file staged = git status shows it [OK]

Hint: Staged files show under 'Changes to be committed' in git status [OK]

Common Mistakes:

• Assuming branch is still main
• Thinking staging clears changes
• Confusing untracked with staged files

4. You created a pull request but reviewers say your branch is behind main and has conflicts. What should you do to fix this?

medium

A. Delete your branch and create a new one

B. Force push your branch without updating

C. Merge main into your branch locally and resolve conflicts

D. Close the pull request and push directly to main

Solution

1. Step 1: Understand the conflict cause

   Your branch is behind main, so changes in main conflict with your branch.

2. Step 2: Fix conflicts by merging main

   Merge main into your branch locally using 'git merge main', resolve conflicts, then push updates to update the pull request.

3. Final Answer:

   Merge main into your branch locally and resolve conflicts -> Option C

4. Quick Check:

   Fix conflicts = merge main and resolve [OK]

Hint: Merge main into your branch to fix conflicts before pushing [OK]

Common Mistakes:

• Force pushing without resolving conflicts
• Deleting branch unnecessarily
• Pushing directly to main ignoring review

5. You want to ensure that every pull request is reviewed by at least two team members before merging. Which GitHub feature should you configure?

hard

A. Enable auto-merge on pull requests

B. Branch protection rules with required reviews

C. Set default branch to feature branch

D. Use git stash before pushing

Solution

1. Step 1: Identify the feature for enforcing reviews

   GitHub branch protection rules allow setting requirements like minimum number of reviewers before merging.

2. Step 2: Understand other options

   Auto-merge merges without review, changing default branch doesn't enforce reviews, and git stash is unrelated to pull requests.

3. Final Answer:

   Branch protection rules with required reviews -> Option B

4. Quick Check:

   Require reviews = branch protection rules [OK]

Hint: Use branch protection rules to require reviews before merge [OK]

Common Mistakes:

• Confusing auto-merge with review enforcement
• Changing default branch instead of protection rules
• Using git stash unrelated to reviews