.gitignore Explained: Ignore Files in Git the Right Way (with Templates)

Some files should never be in Git: dependencies, test reports, logs and especially secrets. In this lesson you will write a proper .gitignore, understand its pattern syntax, use ready-made templates and fix the classic “.gitignore is not working” problem.

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🙈 What Is .gitignore?

Not every file in your project folder belongs in Git. Dependencies, build output, logs, test reports and secrets should stay out of the repository. A .gitignore file is a plain text file, usually in the repository root, that lists patterns of files and folders Git should ignore.

Ignored files do not show up as “untracked” in git status, and git add . skips them.

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🚫 What Should You Ignore?

Category	Examples	Why
Dependencies	node_modules/, venv/, .venv/	Huge, and recreated with npm install or pip install
Build output	dist/, build/, target/, *.class	Generated from source code
Test results and reports	test-results/, playwright-report/, allure-results/, coverage/	Generated on every run
Secrets	.env, *.pem, credentials.json, playwright/.auth/	Must never be shared publicly
Logs and temp files	*.log, *.tmp, .cache/	Noise
OS and editor files	.DS_Store, Thumbs.db, .idea/, .vscode/ (optional)	Personal, not project files

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✍️ Create Your First .gitignore

In the repository root:

# Dependencies
node_modules/

# Environment variables and secrets
.env
.env.*
!.env.example

# Test output
test-results/
playwright-report/
allure-results/

# Logs
*.log

# OS files
.DS_Store
Thumbs.db

Commit the .gitignore file itself so the whole team shares the same rules:

git add .gitignore
git commit -m "Add .gitignore for dependencies, secrets and test output"

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🧩 Pattern Syntax

Pattern	Matches
debug.log	A file named debug.log in any folder
*.log	Any file ending in .log
build/	Any folder named build (and everything inside)
/build/	Only the build folder in the repository root
docs/*.pdf	PDFs directly inside docs, not in its subfolders
docs/**/*.pdf	PDFs anywhere inside docs
**/temp	A temp file or folder at any depth
!important.log	Exception: do not ignore this file (negation)
# comment	A comment line

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🧰 Ready-Made Templates

You rarely write a .gitignore from scratch:

• When creating a repository on GitHub, choose a template from the Add .gitignore dropdown (Node, Python, Java, VisualStudio and many more).
• GitHub maintains the official collection in the github/gitignore repository.
• Generator websites such as gitignore.io combine templates for your language, framework and editor.

Example: Playwright with TypeScript project

node_modules/
/test-results/
/playwright-report/
/blob-report/
/playwright/.cache/
/playwright/.auth/
.env

This matches what npm init playwright@latest generates, plus the folders for saved login sessions and secrets. See Install Playwright.

Example: Python project

__pycache__/
*.py[cod]
.venv/
venv/
.pytest_cache/
.env
reports/

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🧹 Ignoring a File That Is Already Tracked

Adding a file to .gitignore does not affect files Git already tracks. Stop tracking it first:

git rm --cached .env                 # stop tracking, keep the file on disk
git rm -r --cached node_modules      # a whole folder
git commit -m "Stop tracking .env and node_modules"

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🔎 Debugging: Why Is (or Isn’t) a File Ignored?

git check-ignore -v playwright-report/index.html

.gitignore:3:/playwright-report/	playwright-report/index.html

The output shows which file and line caused the match. List everything currently ignored with git status --ignored.

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🌍 Personal Ignore Rules

Rules that only matter to you (your editor or OS) can live outside the project:

Location	Scope
.gitignore in the repo	Everyone working on the project (committed)
.git/info/exclude	Only this repository on your computer (not committed)
Global file, set with git config --global core.excludesFile ~/.gitignore_global	All repositories on your computer

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📝 Assignment

1. In git-practice, create node_modules/test.js, app.log, .env and report/index.html, and check git status.
2. Write a .gitignore that ignores all four, commit it, and check git status again.
3. Add !keep.log as an exception and confirm with git check-ignore -v.
4. Commit a file called secret.txt, then stop tracking it with git rm --cached and ignore it.
5. Set up a global ignore file for your OS and editor files.
6. Bonus: generate a .gitignore for Node, Python and VS Code from a template and compare it with yours.

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❓ FAQ

🤔 What is .gitignore in Git?

A text file that lists files and folders Git should not track, such as dependencies, build output, logs and secrets.

🤔 Why is .gitignore not working?

Usually because the file is already tracked. Run git rm --cached <file> and commit. Also check the pattern with git check-ignore -v <file>.

🤔 Should I commit the .gitignore file?

Yes. Committing it shares the same ignore rules with everyone on the project.

🤔 Should I ignore the .env file?

Yes. .env files usually contain secrets. Commit a .env.example with placeholder values instead.

🤔 How do I ignore a folder in Git?

Add the folder name with a trailing slash, for example node_modules/, to .gitignore.

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🎯 Next Steps

• ↩️ Undo Changes: restore, reset, revert and amend
• 🌐 Remote Repositories: origin, upstream and git remote
• 📘 Git and GitHub Tutorial: full course