Testpaths configuration in PyTest

Introduction

Testpaths configuration helps pytest find your test files easily. It tells pytest where to look for tests.

You have test files in folders other than the default 'tests' folder.

You want to organize tests in multiple directories and still run them all.

You want to avoid pytest searching unnecessary folders for tests.

You want to speed up test discovery by limiting search paths.

You want to keep your project clean by specifying only test folders.

Syntax

PyTest

[pytest]
testpaths = folder1 folder2

This goes in a pytest.ini file in your project root.

List folders separated by spaces where your test files are located.

Examples

Look for tests only in the 'tests' folder.

PyTest

[pytest]
testpaths = tests

Look for tests in both 'tests' and 'integration_tests' folders.

PyTest

[pytest]
testpaths = tests integration_tests

Look for tests inside 'src/tests' folder.

PyTest

[pytest]
testpaths = src/tests

Sample Program

This example shows a pytest.ini file with testpaths set to 'tests'. Pytest will only look inside the 'tests' folder for test files.

The sample test file has two simple tests that both pass.

Running pytest will find and run these tests successfully.

PyTest

[pytest]
testpaths = tests

# Folder structure:
# project_root/
# ├── pytest.ini
# ├── tests/
# │   └── test_sample.py

# Content of tests/test_sample.py:
import pytest

def test_add():
    assert 1 + 1 == 2

def test_subtract():
    assert 5 - 3 == 2

# Run command:
# pytest

# Expected output:
# ============================= test session starts =============================
# collected 2 items
# 
# tests/test_sample.py ..                                                     [100%]
# 
# ============================== 2 passed in 0.01s ==============================

Important Notes

Make sure the folders listed in testpaths actually exist, or pytest will find no tests.

Test files should be named starting with test_ or ending with _test.py for pytest to recognize them.

You can combine testpaths with other pytest.ini settings like python_files to customize test discovery.

Summary

Testpaths configuration tells pytest where to find your test files.

It helps organize tests and speeds up test discovery.

Set it in pytest.ini by listing folders with tests.

Practice

1. What is the main purpose of the testpaths setting in a pytest.ini file?

easy

A. To configure the test report format

B. To specify which folders pytest should look in for test files

C. To set the timeout for each test

D. To define the order in which tests run

Solution

1. Step 1: Understand the role of testpaths

   The testpaths setting tells pytest where to find test files by listing directories.

2. Step 2: Compare with other options

   Other options like test order, timeout, or report format are configured differently, not with testpaths.

3. Final Answer:

   To specify which folders pytest should look in for test files -> Option B

4. Quick Check:

   testpaths = test folders [OK]

Hint: testpaths lists folders to find tests [OK]

Common Mistakes:

• Confusing testpaths with test order settings
• Thinking testpaths sets test timeouts
• Assuming testpaths changes report style

2. Which of the following is the correct syntax to set testpaths in pytest.ini to look in folders tests and integration?

easy

A. [pytest]
testpaths = tests integration

B. [pytest]
testpaths = ['tests', 'integration']

C. [pytest]
testpaths = tests,integration

D. [pytest]
testpaths = "tests integration"

Solution

1. Step 1: Check pytest.ini syntax for testpaths

   In pytest.ini, testpaths lists folders separated by spaces without quotes or commas.

2. Step 2: Validate each option

   [pytest] testpaths = tests integration uses space-separated folder names correctly. Options A and D use quotes or brackets incorrectly. [pytest] testpaths = tests,integration uses commas which pytest does not accept here.

3. Final Answer:

   [pytest] testpaths = tests integration -> Option A

4. Quick Check:

   Space-separated folder names, no quotes [OK]

Hint: Use space-separated folder names without quotes [OK]

Common Mistakes:

• Using commas instead of spaces
• Adding quotes or brackets around folder names
• Placing testpaths outside [pytest] section

3. Given this pytest.ini content:

[pytest]
testpaths = tests integration

And this folder structure:

project/
  tests/
    test_alpha.py
  integration/
    test_beta.py
  docs/
    test_docs.py

Which test files will pytest discover and run?

medium

A. Only test_docs.py

B. test_alpha.py, test_beta.py, and test_docs.py

C. Only test_alpha.py

D. test_alpha.py and test_beta.py only

Solution

1. Step 1: Identify folders listed in testpaths

   The testpaths setting includes tests and integration folders only.

2. Step 2: Match test files in those folders

   Files test_alpha.py in tests and test_beta.py in integration will be found. test_docs.py is in docs, which is not listed.

3. Final Answer:

   test_alpha.py and test_beta.py only -> Option D

4. Quick Check:

   Only testpaths folders' tests run [OK]

Hint: Only tests in testpaths folders run [OK]

Common Mistakes:

• Assuming all test files in project run
• Including tests from folders not in testpaths
• Confusing folder names with test file names

4. You set testpaths = tests in pytest.ini but pytest still discovers tests in other folders. What is the most likely cause?

medium

A. There is another config file overriding testpaths

B. You forgot to restart pytest after editing pytest.ini

C. testpaths only filters test names, not folders

D. pytest ignores testpaths by default

Solution

1. Step 1: Understand pytest config precedence

   pytest can read multiple config files like tox.ini or setup.cfg that may override pytest.ini.

2. Step 2: Check for conflicting configs

   If tests outside tests run, likely another config file sets different testpaths or disables it.

3. Final Answer:

   There is another config file overriding testpaths -> Option A

4. Quick Check:

   Multiple configs can override testpaths [OK]

Hint: Check for multiple config files overriding settings [OK]

Common Mistakes:

• Assuming pytest.ini changes apply without reload
• Thinking testpaths filters test names only
• Believing pytest ignores testpaths by default

5. You want pytest to only run tests in unit_tests and api_tests folders, but exclude api_tests/slow. How can you configure pytest.ini using testpaths and other settings to achieve this?

hard

A. [pytest]
testpaths = unit_tests
norecursedirs = api_tests/slow

B. [pytest]
testpaths = unit_tests api_tests/slow
norecursedirs = api_tests

C. [pytest]
testpaths = unit_tests api_tests
norecursedirs = api_tests/slow

D. [pytest]
testpaths = unit_tests api_tests
ignore = api_tests/slow

Solution

1. Step 1: Use testpaths to include desired folders

   Set testpaths = unit_tests api_tests to include both folders.

2. Step 2: Exclude the slow subfolder with norecursedirs

   Use norecursedirs = api_tests/slow to prevent pytest from searching inside that subfolder.

3. Step 3: Verify other options are incorrect

   [pytest] testpaths = unit_tests api_tests/slow norecursedirs = api_tests includes the slow folder in testpaths, which is wrong. [pytest] testpaths = unit_tests norecursedirs = api_tests/slow excludes api_tests entirely. [pytest] testpaths = unit_tests api_tests ignore = api_tests/slow uses ignore which is not a valid pytest.ini setting.

4. Final Answer:

   [pytest] testpaths = unit_tests api_tests norecursedirs = api_tests/slow -> Option C

5. Quick Check:

   Include folders with testpaths, exclude subfolders with norecursedirs [OK]

Hint: Use testpaths to include, norecursedirs to exclude subfolders [OK]

Common Mistakes:

• Including excluded folders in testpaths
• Using invalid config keys like ignore
• Excluding whole folders instead of subfolders