Trunk-based development in Git - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is trunk-based development?

Trunk-based development is a way to work on code where everyone adds their changes directly to one main branch called the trunk or main branch. This helps keep the code simple and up to date.

beginner

Why do teams prefer trunk-based development?

Teams like trunk-based development because it reduces conflicts, makes testing easier, and helps deliver new features faster by keeping all work in one main branch.

intermediate

What is a short-lived feature branch in trunk-based development?

A short-lived feature branch is a small branch created for a quick change or feature. It is merged back into the trunk quickly to avoid long delays and conflicts.

intermediate

How does continuous integration relate to trunk-based development?

Continuous integration means automatically testing and merging code often. It works well with trunk-based development because changes are small and frequent, making problems easier to find and fix.

beginner

What is a common risk if trunk-based development is not followed properly?

If trunk-based development is not followed, big conflicts can happen, code can break often, and it becomes hard to deliver updates quickly.

In trunk-based development, where do developers usually commit their changes?

A Directly to the main trunk branch

B To long-lived feature branches

C Only to release branches

D To personal forks only

In trunk-based development, developers commit directly to the main trunk branch or very short-lived branches merged quickly.

What is a key benefit of trunk-based development?

A Uses many long-lived branches

B Avoids merge conflicts by merging often

C Requires no testing

D Keeps features hidden for months

Merging often in trunk-based development helps avoid big merge conflicts.

Which practice supports trunk-based development best?

A No code reviews

B Manual testing after release

C Continuous integration with automated tests

D Working in isolation for weeks

Continuous integration with automated tests helps catch problems early in trunk-based development.

How long should feature branches be kept in trunk-based development?

A Several months

B Only after release

C Never merged

D Very short-lived, merged quickly

Feature branches should be short-lived and merged quickly to keep the trunk updated.

What happens if many developers work on long-lived branches instead of trunk?

A More merge conflicts and delays

B Faster delivery

C Simpler codebase

D No need for testing

Long-lived branches increase merge conflicts and slow down delivery.

Explain trunk-based development and why it helps teams deliver software faster.

Think about how working together on one main branch can make things simpler.

Describe how continuous integration supports trunk-based development.

Consider how testing often helps keep the main branch healthy.

Practice

1. What is the main idea behind trunk-based development?

easy

A. Developing mostly on one main branch to avoid big merge conflicts

B. Creating many long-lived branches for each feature

C. Working only on local branches without pushing to remote

D. Merging branches only once a month

Solution

1. Step 1: Understand trunk-based development concept

   It focuses on working mainly on one main branch, often called trunk or main.

2. Step 2: Compare options with this concept

   Options A, C, and D describe practices that do not align with trunk-based development principles.

3. Final Answer:

   Developing mostly on one main branch to avoid big merge conflicts -> Option A

4. Quick Check:

   Trunk-based development = one main branch [OK]

Hint: Remember: trunk means main branch work mostly [OK]

Common Mistakes:

• Thinking trunk means many long-lived branches
• Believing merges happen rarely in trunk-based
• Confusing local-only work with trunk-based

2. Which of the following git commands is best to quickly merge a short-lived feature branch back to main in trunk-based development?

easy

A. git merge feature-branch

B. git rebase feature-branch

C. git checkout feature-branch

D. git branch -d feature-branch

Solution

1. Step 1: Identify the command to merge branches

   git merge feature-branch merges the feature branch into the current branch, usually main.

2. Step 2: Check other commands

   git rebase rewrites history, git checkout switches branches, and git branch -d deletes a branch but does not merge.

3. Final Answer:

   git merge feature-branch -> Option A

4. Quick Check:

   Merge short-lived branch = git merge [OK]

Hint: Merge feature branch with git merge [OK]

Common Mistakes:

• Using git checkout instead of merging
• Deleting branch before merging
• Confusing rebase with merge

3. Given this sequence of commands in trunk-based development:

git checkout main
git pull origin main
git checkout -b feature
# make changes
 git commit -am 'Add feature'
git checkout main
git merge feature

What is the state of the main branch after these commands?

medium

A. Main branch is unchanged and does not have feature changes

B. Main branch has the new feature changes merged in

C. Feature branch is deleted automatically

D. Main branch is behind origin/main

Solution

1. Step 1: Follow the commands step-by-step

   Start on main, update it from origin, create feature branch, commit changes, switch back to main, then merge feature into main.

2. Step 2: Understand merge effect

   After merge, main branch includes the feature changes locally.

3. Final Answer:

   Main branch has the new feature changes merged in -> Option B

4. Quick Check:

   Merge feature into main = main updated [OK]

Hint: Merge updates main branch with feature changes [OK]

Common Mistakes:

• Assuming merge deletes feature branch automatically
• Thinking main is unchanged after merge
• Forgetting to pull origin before branching

4. You tried to merge a short-lived branch into main but got a conflict error. What is the best way to fix this in trunk-based development?

medium

A. Force push main branch to overwrite remote

B. Delete the feature branch and start over

C. Resolve conflicts manually, then commit the merge

D. Ignore conflicts and continue

Solution

1. Step 1: Understand merge conflicts

   Conflicts happen when changes overlap. They must be fixed manually to keep code correct.

2. Step 2: Choose correct resolution

   Resolving conflicts manually and committing is the proper way. Deleting branch or ignoring conflicts causes problems.

3. Final Answer:

   Resolve conflicts manually, then commit the merge -> Option C

4. Quick Check:

   Fix conflicts manually = merge success [OK]

Hint: Fix conflicts manually before committing merge [OK]

Common Mistakes:

• Ignoring conflicts thinking git fixes automatically
• Deleting branch instead of resolving
• Force pushing without resolving conflicts

5. In trunk-based development, a team wants to avoid long-lived branches but still work on multiple features simultaneously. Which strategy fits best?

hard

A. Work only on main branch without any feature branches

B. Keep all features in one big branch for weeks before merging

C. Use separate repositories for each feature

D. Create short-lived feature branches, merge them quickly to main, and deploy often

Solution

1. Step 1: Understand trunk-based development goals

   It encourages short-lived branches merged quickly to main to reduce conflicts and speed releases.

2. Step 2: Evaluate options

   Create short-lived feature branches, merge them quickly to main, and deploy often matches this approach. Keep all features in one big branch for weeks before merging causes long-lived branches. Work only on main branch without any feature branches limits parallel work. Use separate repositories for each feature complicates repo management.

3. Final Answer:

   Create short-lived feature branches, merge them quickly to main, and deploy often -> Option D

4. Quick Check:

   Short-lived branches + quick merge = trunk-based best practice [OK]

Hint: Use short-lived branches merged fast to main [OK]

Common Mistakes:

• Thinking all work must be on main only
• Using long-lived branches defeats trunk-based purpose
• Splitting features into separate repos unnecessarily