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Manuals / Python / Chapter 7

C · Testing · intermediate · Week 3 · Chapter 7 of 13

pytest fundamentals

Arrange-act-assert. test_ prefix. assert directly. pytest discovers tests/ automatically.

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First tests

test_is_valid_email_true(), test_is_valid_email_false(). No unittest boilerplate.

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Example

# tests/test_helpers.py
from src.helpers import is_valid_email

def test_valid_email():
    assert is_valid_email("a@b.com") is True

def test_invalid_email():
    assert is_valid_email("nope") is False

Do this now

5 pytest tests for helpers from earlier chapters. pytest -v.

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Chapter learning outcomes
  • pytest discovery
  • assert style
  • Running pytest
  • Test naming

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Side quest

Config tests

Test load_config with missing file raises or returns default.