pre-push hook in Git - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a pre-push hook script that runs before pushing.

Git

#!/bin/sh

[1]

Drag options to blanks, or click blank then click option'

Agit status

Bgit push origin main

Cgit commit -m 'pre-push'

Decho "Running pre-push hook"

Attempts:

3 left

💡 Hint

Common Mistakes

Trying to push inside the pre-push hook causes recursion.

Using git commit in the hook is incorrect.

The pre-push hook script runs commands before pushing. Using echo shows a message.

2fill in blank

medium

Complete the code to make the pre-push hook stop the push if tests fail.

Git

#!/bin/sh

if ! [1]; then
  echo "Tests failed, push aborted."
  exit 1
fi

Drag options to blanks, or click blank then click option'

Agit push

Bmake test

Cecho 'test'

Dls

Attempts:

3 left

💡 Hint

Common Mistakes

Using git push inside the hook causes infinite loops.

Using commands that don't test code.

The hook runs make test to check tests. If tests fail, it stops the push.

3fill in blank

hard

Fix the error in the pre-push hook to correctly check for staged changes.

Git

#!/bin/sh

if git diff --quiet [1]; then
  echo "No staged changes."
else
  echo "Staged changes found. Push aborted."
  exit 1
fi

Drag options to blanks, or click blank then click option'

A--cached

B--staged

C--all

D--untracked

Attempts:

3 left

💡 Hint

Common Mistakes

Using invalid git diff options.

Confusing staged and unstaged changes.

The --cached option checks for staged changes. Without it, git diff --quiet checks unstaged changes.

4fill in blank

hard

Fill both blanks to create a pre-push hook that runs tests and lints code before pushing.

Git

#!/bin/sh

if ! [1]; then
  echo "Tests failed. Push aborted."
  exit 1
fi

if ! [2]; then
  echo "Lint errors found. Push aborted."
  exit 1
fi

Drag options to blanks, or click blank then click option'

Anpm test

Bgit status

Cnpm run lint

Decho 'linting'

Attempts:

3 left

💡 Hint

Common Mistakes

Using commands that don't check code quality.

Not exiting with error on failure.

The hook runs npm test to check tests and npm run lint to check code style before pushing.

5fill in blank

hard

Fill all three blanks to create a pre-push hook that checks tests, lint, and code formatting.

Git

#!/bin/sh

if ! [1]; then
  echo "Tests failed. Push aborted."
  exit 1
fi

if ! [2]; then
  echo "Lint errors found. Push aborted."
  exit 1
fi

if ! [3]; then
  echo "Code formatting issues. Push aborted."
  exit 1
fi

Drag options to blanks, or click blank then click option'

Anpm test

Bnpm run lint

Cnpm run format:check

Dgit status

Attempts:

3 left

💡 Hint

Common Mistakes

Forgetting to check formatting.

Using git status instead of test commands.

The hook runs tests, linting, and formatting checks using npm test, npm run lint, and npm run format:check.

Practice

1. What is the main purpose of a pre-push hook in Git?

easy

A. To delete local branches after pushing

B. To merge branches automatically before pushing

C. To run checks or tests before code is pushed to a remote repository

D. To create a backup of the repository before pushing

Solution

1. Step 1: Understand the role of pre-push hooks

   Pre-push hooks run scripts before pushing code to a remote repository to catch errors early.

2. Step 2: Identify the correct purpose

   They help ensure code quality by running tests or checks before the push happens.

3. Final Answer:

   To run checks or tests before code is pushed to a remote repository -> Option C

4. Quick Check:

   Pre-push hook = run checks before push [OK]

Hint: Pre-push hooks run before push to catch problems early [OK]

Common Mistakes:

• Confusing pre-push with post-push hooks
• Thinking it merges branches automatically
• Assuming it deletes branches

2. Which of the following is the correct way to make a pre-push hook script executable on Linux or macOS?

easy

A. chmod +x .git/hooks/pre-push

B. git enable pre-push

C. chmod 777 .git/hooks/pre-push

D. git hook activate pre-push

Solution

1. Step 1: Identify how to make scripts executable

   On Linux/macOS, chmod +x sets execute permission on a file.

2. Step 2: Apply to pre-push hook

   Running chmod +x .git/hooks/pre-push makes the hook script runnable by Git.

3. Final Answer:

   chmod +x .git/hooks/pre-push -> Option A

4. Quick Check:

   Make hook executable = chmod +x [OK]

Hint: Use chmod +x to make hook scripts executable [OK]

Common Mistakes:

• Using git commands that don't exist for hooks
• Setting overly permissive permissions like 777
• Forgetting to make the script executable

3. Given this pre-push hook script snippet, what will happen if the tests fail?

#!/bin/sh
npm test || exit 1

medium

A. The push will continue regardless of test results

B. The script will delete the remote branch

C. The tests will be skipped

D. The push will be blocked and stopped

Solution

1. Step 1: Understand the script logic

   The script runs npm test. If tests fail, npm test returns non-zero, triggering exit 1.

2. Step 2: Effect of exit 1 in pre-push hook

   Exiting with a non-zero code stops the push process, blocking the push.

3. Final Answer:

   The push will be blocked and stopped -> Option D

4. Quick Check:

   Exit 1 in pre-push = block push [OK]

Hint: Exit non-zero in pre-push stops the push [OK]

Common Mistakes:

• Assuming push continues even if tests fail
• Thinking tests are skipped automatically
• Confusing exit codes with success

4. You wrote a pre-push hook script but it does not run when you push. What is the most likely cause?

medium

A. The remote repository is down

B. The script is missing execute permissions

C. You forgot to commit your changes

D. The branch name is incorrect

Solution

1. Step 1: Check script execution requirements

   Git requires hook scripts to have execute permission to run them.

2. Step 2: Identify common cause of hook not running

   If the script lacks execute permission, Git silently skips running it.

3. Final Answer:

   The script is missing execute permissions -> Option B

4. Quick Check:

   Missing execute permission = hook won't run [OK]

Hint: Check execute permission if hook doesn't run [OK]

Common Mistakes:

• Blaming remote repository for local hook issues
• Thinking commit status affects hook execution
• Assuming branch name affects hook running

5. You want your pre-push hook to run tests only on files changed in the last commit before pushing. Which approach is best?

hard

A. Use git diff --name-only HEAD~1 HEAD inside the hook to get changed files and run tests accordingly

B. Run tests on all files every time without checking changes

C. Manually list files in the hook script each time

D. Push first, then run tests on the remote repository

Solution

1. Step 1: Identify how to detect changed files

   The command git diff --name-only HEAD~1 HEAD lists files changed in the last commit.

2. Step 2: Use this command in pre-push hook

   Using this inside the hook lets you run tests only on changed files, saving time and resources.

3. Final Answer:

   Use git diff --name-only HEAD~1 HEAD inside the hook to get changed files and run tests accordingly -> Option A

4. Quick Check:

   Detect changed files with git diff for selective tests [OK]

Hint: Use git diff to find changed files for selective tests [OK]

Common Mistakes:

• Running tests on all files unnecessarily
• Manually updating file lists each time
• Running tests after push instead of before