File system testing with tmp_path in PyTest - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the purpose of the tmp_path fixture in pytest?

The tmp_path fixture provides a temporary directory unique to the test function. It allows tests to create and manipulate files and directories without affecting the real file system.

intermediate

How does tmp_path differ from tmpdir in pytest?

tmp_path returns a pathlib.Path object, which is modern and more versatile, while tmpdir returns a py.path.local object. tmp_path is preferred for new tests.

beginner

How do you create a new file named example.txt inside the tmp_path directory in a pytest test?

Use file = tmp_path / 'example.txt' to create a path object, then file.write_text('content') to write text to the file.

beginner

Why is it important to use tmp_path for file system tests?

Using tmp_path isolates test files from the real file system, preventing accidental data loss or pollution. It also ensures tests are independent and repeatable.

beginner

What happens to the files and directories created by tmp_path after the test finishes?

The temporary directory and all its contents are automatically deleted after the test completes, keeping the environment clean.

What type of object does pytest's tmp_path fixture provide?

A A pathlib.Path object

B A string path

C A py.path.local object

D A file descriptor integer

tmp_path returns a pathlib.Path object for modern path handling.

Which of the following is a benefit of using tmp_path in tests?

A It automatically uploads files to cloud storage

B It permanently saves test files for later use

C It speeds up test execution by caching files

D It isolates test files from the real file system

tmp_path creates a temporary directory isolated from the real file system.

How do you write text 'hello' to a file named 'greet.txt' inside tmp_path?

A (tmp_path / 'greet.txt').write_text('hello')

B tmp_path.write_text('hello')

C tmp_path / 'greet.txt'.write_text('hello')

D write_text(tmp_path, 'greet.txt', 'hello')

You must create the file path first with (tmp_path / 'greet.txt'), then call write_text on it.

What happens to the temporary directory created by tmp_path after the test ends?

A It remains on disk for debugging

B It is archived as a zip file

C It is deleted automatically

D It is moved to a backup folder

pytest cleans up the temporary directory automatically after the test.

Which pytest fixture is recommended for new file system tests?

A tmpdir

B tmp_path

C tmpfile

D tempfile

tmp_path is preferred over tmpdir for modern tests.

Explain how to use the pytest tmp_path fixture to create and write to a file in a test.

Think about pathlib.Path usage and test isolation.

Why is using tmp_path important for file system testing in pytest?

Consider risks of testing with real files.