Git configuration (user.name, user.email) - Practice Problems & Coding Challenges

Challenge - 5 Problems

💻 Command Output

intermediate

Check current Git user name configuration

What is the output of the command git config --global user.name if the global user name is set to "Alice Dev"?

Git

git config --global user.name

A null

B user.name

C error: key does not exist

D Alice Dev

💡 Hint

This command shows the global user name set in Git configuration.

The command git config --global user.name outputs the global user name string exactly as set, here "Alice Dev".

💻 Command Output

intermediate

Effect of missing user.email in Git commit

What error message appears if you try to commit in Git but the user.email is not set anywhere in the configuration?

Git

git commit -m "Test commit"

A error: user.email is not set

B fatal: unable to auto-detect email address (got 'username@hostname')

C commit created successfully

D warning: user.email is empty, using default

💡 Hint

Git needs an email to identify the author of commits.

If user.email is not set, Git tries to guess but fails and shows a fatal error about unable to auto-detect email address.

❓ Configuration

advanced

Set local Git user name and email for a repository

Which commands correctly set the local Git user name to "Bob Builder" and email to "[e-mail]" only for the current repository?

A

git config user.name "Bob Builder"
git config user.email "[e-mail]"

B

git config --global user.name "Bob Builder"
git config --global user.email "[e-mail]"

C

git config --local user.name "Bob Builder"
git config --local user.email "[e-mail]"

D

git config --system user.name "Bob Builder"
git config --system user.email "[e-mail]"

💡 Hint

Local config is the default when no flag is given.

Running git config user.name without flags sets the value only for the current repository (local). The --global flag sets it globally, and --system sets system-wide.

❓ Troubleshoot

advanced

Diagnose why Git commit uses wrong email

You set your global Git email to "[e-mail]" but commits in a specific repository show author email as "[e-mail]". What is the most likely cause?

A Git caches old email and needs restart

B Global config is ignored if user.name is missing

C The repository has a local user.email set to "[e-mail]" overriding global config

D The commit message contains the old email explicitly

💡 Hint

Local config overrides global config in Git.

Git uses the local repository config first if set. If user.email is set locally, it overrides the global setting.

✅ Best Practice

expert

Best practice for managing Git user identity across multiple projects

You work on personal and work projects on the same machine. What is the best way to manage your Git user.name and user.email to keep identities separate?

A Set global user.name and user.email to your personal info, then set local user.name and user.email in work repos to work info

B Set global user.name and user.email to work info, then override locally for personal projects

C Use only global config for all projects and manually change before commits

D Set user.name and user.email only in system config for all projects

💡 Hint

Global config is default; local config overrides it per repo.

Setting global config to personal info and overriding locally for work repos keeps identities clean and automatic.

Practice

1. What is the purpose of setting user.name and user.email in Git configuration?

easy

A. To set the default branch name

B. To enable Git debugging mode

C. To configure the remote repository URL

D. To label your commits with your identity

Solution

1. Step 1: Understand Git commit metadata

   Git uses user.name and user.email to identify who made each commit.

2. Step 2: Recognize the role of these settings

   These settings label your work so others know who made changes.

3. Final Answer:

   To label your commits with your identity -> Option D

4. Quick Check:

   user.name and user.email = commit identity [OK]

Hint: Remember: name and email tag your commits [OK]

Common Mistakes:

• Confusing user.name with branch name
• Thinking user.email sets remote URL
• Assuming these enable debugging

2. Which command correctly sets your global Git user email to "[e-mail]"?

easy

A. git config --email [e-mail] --global

B. git config --global user.email [e-mail]

C. git config user.email --global [e-mail]

D. git set user.email global [e-mail]

Solution

1. Step 1: Recall correct Git config syntax

   The correct syntax is git config --global key value.

2. Step 2: Match the command to set user.email globally

   git config --global user.email [e-mail] matches this syntax exactly.

3. Final Answer:

   git config --global user.email [e-mail] -> Option B

4. Quick Check:

   git config --global key value sets global config [OK]

Hint: Use 'git config --global key value' format [OK]

Common Mistakes:

• Swapping order of flags and values
• Using 'git set' instead of 'git config'
• Placing --global after the key

3. Given these commands run in order:

git config --global user.name "Alice"
git config user.name "Bob"

What will git config user.name output inside the current repository?

medium

A. Bob

B. No output (empty)

C. Alice

D. Error: user.name not set

Solution

1. Step 1: Understand global vs local config

   The first command sets user.name globally to "Alice". The second sets it locally to "Bob" in the current repo.

2. Step 2: Determine which config is used

   Local config overrides global inside the repo, so git config user.name shows "Bob".

3. Final Answer:

   Bob -> Option A

4. Quick Check:

   Local config overrides global config [OK]

Hint: Local config overrides global config [OK]

Common Mistakes:

• Assuming global always overrides local
• Expecting empty output if local set
• Confusing command order effects

4. You run git config user.email "wrongemail.com" but your commits still show the old email. What is the likely problem?

medium

A. You forgot to add --global or --local, so it set config in an unexpected scope

B. The email format is invalid, so Git ignored the setting

C. You need to restart Git for changes to apply

D. Git does not allow changing user.email once set

Solution

1. Step 1: Check command scope

   Without --global or --local, Git sets config in the current repo (local) by default.

2. Step 2: Understand why commits show old email

   If commits show old email, likely you changed config in a different scope than where commits are made.

3. Final Answer:

   You forgot to add --global or --local, so it set config in an unexpected scope -> Option A

4. Quick Check:

   Config scope matters; missing flags cause confusion [OK]

Hint: Always specify --global or --local to avoid confusion [OK]

Common Mistakes:

• Assuming Git ignores invalid emails silently
• Thinking Git needs restart after config change
• Believing user.email is immutable

5. You want to set different user names and emails for two projects on the same computer. How do you configure Git correctly?

hard

A. Set user.name and user.email only locally in one project; global config is ignored

B. Set user.name and user.email only globally; Git automatically detects project differences

C. Set global user.name and user.email once, then override locally per project with git config user.name and git config user.email

D. Use environment variables instead of Git config to set user identity

Solution

1. Step 1: Understand global and local config roles

   Global config applies to all repos unless overridden locally.

2. Step 2: Apply local overrides per project

   Set local user.name and user.email in each project to customize identity per repo.

3. Final Answer:

   Set global user.name and user.email once, then override locally per project with git config user.name and git config user.email -> Option C

4. Quick Check:

   Global sets default; local overrides per project [OK]

Hint: Global sets default; local overrides per project [OK]

Common Mistakes:

• Expecting Git to auto-detect project identities
• Setting only local config and ignoring global
• Using environment variables instead of config