Pytest is a widely-used testing framework for Python that simplifies the process of writing and executing test cases. It is known for its simplicity, scalability, and powerful features.
Pytest supports various types of tests, including unit tests, functional tests, and acceptance tests.
Pytest is one of the most popularly used Python testing frameworks. It is an open-source testing framework. Pytest supports unit testing, functional testing, and API tests.
Prerequisites for Pytest Framework:
- Install Python version 3.5 or above.
Key Benefits of Pytest Framework:
- Provides a compact and simple test suite.
- Highly extensible with many plugins available, such as the Pytest HTML plugin, which can be added to your project to print HTML reports with a single command-line option.
- It has large community support.
- It helps to cover all parameter combinations without rewriting test cases.
Disadvantages of Pytest Framework:
Pytest’s proprietary routines prevent compatibility. This means that though the test cases can be easily written in this framework, you won’t be able to use those in other testing frameworks.
Here are some key features and concepts associated with Pytest:
1. Simple Syntax:
Pytest uses a concise and easy-to-read syntax for writing test functions. Test functions are identified by the use of the test_ prefix or by using the @pytest.mark decorator.
def test_addition():
assert 1 + 1 == 2
2. Fixtures:
Pytest provides a powerful fixture mechanism to set up and tear down resources needed for testing. Fixtures can be used to manage test data, initialize objects, and handle other setup tasks.
import pytest
@pytest.fixture
def setup_data():
data = {"key": "value"}
return data
def test_using_fixture(setup_data):
assert "key" in setup_data
3. Parameterized Testing:
Pytest supports parameterized testing, allowing you to run the same test with different sets of input parameters.
import pytest
@pytest.mark.parametrize("input, expected", [(1, 2), (2, 4), (3, 6)])
def test_multiply_by_two(input, expected):
result = input * 2
assert result == expected
4. Plugins and Extensibility:
Pytest has a rich ecosystem of plugins that extend its functionality. You can use existing plugins or create your own to customize the testing process according to your needs.
5. Assertions:
Pytest provides a set of powerful built-in assertions that make it easy to write expressive and informative test cases.
def test_strings():
assert "hello" == "hello"
assert "world" in "hello world"
6. Test Discovery:
Pytest automatically discovers and runs test functions and methods in your project. You don’t need to explicitly specify test files or classes.
# Run all tests in the current directory
pytest
7. Fixture Scope:
Pytest allows you to control the scope of fixtures, such as function-level, class-level, module-level, or session-level.
import pytest
@pytest.fixture(scope="module")
def module_fixture():
# Fixture setup code
yield
# Fixture teardown code
To use Pytest, you need to install it first. You can do this using the following command:
pip install pytest
Once installed, you can start writing and running your tests with Pytest.