In pytest, you can pass arguments to your test functions by using the command line. To do this, you can use the -k
option followed by the expression that matches the test functions you want to run. For example, to run test functions that contain the word "login" in their names, you can use the command pytest -k "login"
.
You can also pass custom arguments to your test functions by using the -m
option followed by a marker expression. For example, if you have marked a test function with the smoke
marker, you can run it using the command pytest -m smoke
.
Additionally, you can pass custom command line arguments to your test functions by using the -v
option followed by the name of the argument and its value. For example, pytest -v --myarg=myvalue
.
By passing arguments in pytest by command line, you can easily customize and control which test functions are run and how they are run.
What is the recommended way to pass arguments in pytest tests?
The recommended way to pass arguments in pytest tests is to use fixtures. Fixtures provide a way to set up and tear down objects and resources needed for testing, as well as provide a way to pass arguments to test functions. You can define fixtures in conftest.py files in your test directories, and then use them in your test functions by including the fixture name as an argument in the test function definition. This allows you to pass arguments to your test functions in a clean and structured way.
How to pass arguments in pytest using the --fixture option?
In pytest, you can pass arguments to fixtures using the configuration option --fixture
when running tests from the command line. Here's how you can pass arguments to fixtures using the --fixture
option:
- Define a fixture in your test code that accepts arguments:
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import pytest @pytest.fixture def custom_fixture(request): arg = request.param return f'Custom fixture with argument: {arg}' |
- Create a test function that uses the fixture and passes arguments to it:
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import pytest @pytest.mark.parametrize('custom_fixture', ['argument_value'], indirect=True) def test_using_custom_fixture(custom_fixture): assert custom_fixture == 'Custom fixture with argument: argument_value' |
- Run the test using the --fixture option and pass arguments to the fixture:
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pytest --fixture=custom_fixture:argument_value
|
This will run the test test_using_custom_fixture
and pass the argument 'argument_value'
to the fixture custom_fixture
.pytest will automatically inject the argument into the fixture and use it when setting up the fixture for the test function.
Note that you can pass multiple arguments to a fixture by separating them with commas:
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pytest --fixture=custom_fixture:argument1,argument2
|
This allows you to customize the behavior of fixtures based on the arguments passed to them.
How to pass environment variables as arguments in pytest command line?
To pass environment variables as arguments in pytest command line, you can use the -x
option followed by the environment variable you want to pass. For example, if you want to pass the DEBUG
environment variable with a value of True
, you can use the following command:
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pytest -x --env DEBUG=True
|
In your test script, you can then access the environment variable like this:
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import os DEBUG = os.getenv('DEBUG', 'False') |
This will set the DEBUG
variable to True
in your test script if it was passed as an argument in the pytest command line, otherwise it will default to False
.
What is the importance of custom arguments in pytest command line?
Custom arguments in the pytest command line allow testers to customize their test runs by specifying certain parameters or options. Some important aspects of custom arguments in pytest command line include:
- Customizing test runs: Custom arguments allow testers to specify which tests to run, which files to include or exclude, and other specific options. This helps in tailoring the test execution to meet specific testing requirements.
- Debugging and troubleshooting: Custom arguments can be used to set debugging options, such as verbose mode, or to enable certain plugins or hooks for troubleshooting purposes. This can help testers to identify and fix issues more effectively.
- Integrating with other tools: Custom arguments can be used to integrate pytest with other tools or systems by passing required parameters or configurations. This allows testers to seamlessly incorporate pytest into their existing workflows.
- Performance optimization: Custom arguments provide options for controlling the execution process, such as parallel testing or re-running failed tests. This can help in optimizing test execution performance and improving overall efficiency.
In summary, custom arguments in pytest command line are important for tailoring test runs, debugging and troubleshooting, integrating with other tools, and optimizing test performance. They offer flexibility and control to testers in managing their testing processes effectively.
How to override default arguments in pytest command line?
To override default arguments in pytest command line, you can use the -k
(to select tests based on their name), -m
(to select tests based on markers), -x
(to stop running tests after the first failure), or any other pytest command line options.
For example, if you have a test function with a default argument:
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import pytest def test_function(default_arg=10): assert default_arg == 10 |
You can override the default argument value by running pytest with the -k
option:
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pytest -k "test_function(20)"
|
This will run the test function test_function
with the argument value of 20
, instead of the default value of 10
.
You can also use the -m
option to run tests based on markers:
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@pytest.mark.parametrize("arg", [20]) def test_function(arg): assert arg == 20 |
Then you can override the default argument value by running pytest with the -m
option:
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pytest -m "parametrize"
|
This will run the test function test_function
with the argument value of 20
, specified in the parametrize marker.
You can use these options in combination with other pytest command line options to customize the test selection and behavior according to your needs.
How to pass multiple arguments in pytest by command line?
To pass multiple arguments in pytest by command line, you can use the -k
option followed by a pattern that matches the names of the test functions you want to run. For example:
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pytest -k "test_function1 or test_function2"
|
This command will run the test functions test_function1
and test_function2
. You can specify multiple test functions by separating them with or
.
You can also use the -m
option to select tests based on markers:
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pytest -m "marker1 and not marker2"
|
This command will run tests that have the marker marker1
but not the marker marker2
. You can combine multiple markers using and
, or
, and not
logical operators.
You can also use the -k
and -m
options together to further filter the tests you want to run.
Additionally, you can use the --keyword
, --markers
, or --junitxml
options to pass multiple arguments to pytest in the command line. Visit the pytest documentation for more information on how to use these options: https://docs.pytest.org/en/latest/index.html.