Python Install Html Test Runner
Testing your code is very important.
Getting used to writing testing code and running this code in parallel is nowconsidered a good habit. Used wisely, this method helps to define yourcode’s intent more precisely and have a more decoupled architecture.
- Register a runner. Install GitLab Runner as a service and start it. You can either run the service using the Built-in System Account (recommended) or using a user account. Run service using Built-in System Account (under directory created in step 1. From above, ex.: C: GitLab-Runner).
- If you’re unsure of which datasets/models you’ll need, you can install the “popular” subset of NLTK data, on the command line type python -m nltk.downloader popular, or in the Python interpreter import nltk; nltk.download(‘popular’).
Some general rules of testing:
Pass above test runner object to unittest.main method to run it. Then you can find the output Html report file in the output directory. Generate Xml Test Reports. Install python xmlrunner module. Import python xmlrunner module and create XMLTestRunner object. Run the XMLTestRunner object with unittest.main method. Unit Testing is the first level of software testing where the smallest testable parts of a software are tested. This is used to validate that each unit of the software performs as designed. The unittest test framework is python’s xUnit style framework. White Box Testing method is used for Unit testing. A test fixture is used as a baseline for.
- A testing unit should focus on one tiny bit of functionality and prove itcorrect.
- Each test unit must be fully independent. Each test must be able to runalone, and also within the test suite, regardless of the order that they arecalled. The implication of this rule is that each test must be loaded witha fresh dataset and may have to do some cleanup afterwards. This isusually handled by
setUp()
andtearDown()
methods. - Try hard to make tests that run fast. If one single test needs more than afew milliseconds to run, development will be slowed down or the tests willnot be run as often as is desirable. In some cases, tests can’t be fastbecause they need a complex data structure to work on, and this data structuremust be loaded every time the test runs. Keep these heavier tests in aseparate test suite that is run by some scheduled task, and run all othertests as often as needed.
- Learn your tools and learn how to run a single test or a test case. Then,when developing a function inside a module, run this function’s testsfrequently, ideally automatically when you save the code.
- Always run the full test suite before a coding session, and run it againafter. This will give you more confidence that you did not break anythingin the rest of the code.
- It is a good idea to implement a hook that runs all tests before pushingcode to a shared repository.
- If you are in the middle of a development session and have to interruptyour work, it is a good idea to write a broken unit test about what youwant to develop next. When coming back to work, you will have a pointerto where you were and get back on track faster.
- The first step when you are debugging your code is to write a new testpinpointing the bug. While it is not always possible to do, those bugcatching tests are among the most valuable pieces of code in your project.
- Use long and descriptive names for testing functions. The style guide hereis slightly different than that of running code, where short names areoften preferred. The reason is testing functions are never called explicitly.
square()
or evensqr()
is ok in running code, but in testing code youwould have names such astest_square_of_number_2()
,test_square_negative_number()
. These function names are displayed whena test fails, and should be as descriptive as possible. - When something goes wrong or has to be changed, and if your code has agood set of tests, you or other maintainers will rely largely on thetesting suite to fix the problem or modify a given behavior. Thereforethe testing code will be read as much as or even more than the runningcode. A unit test whose purpose is unclear is not very helpful in thiscase.
- Another use of the testing code is as an introduction to new developers. Whensomeone will have to work on the code base, running and reading the relatedtesting code is often the best thing that they can do to start. They willor should discover the hot spots, where most difficulties arise, and thecorner cases. If they have to add some functionality, the first step shouldbe to add a test to ensure that the new functionality is not already aworking path that has not been plugged into the interface.
The Basics¶
unittest¶
unittest
is the batteries-included test module in the Python standardlibrary. Its API will be familiar to anyone who has used any of theJUnit/nUnit/CppUnit series of tools.
Creating test cases is accomplished by subclassing unittest.TestCase
. Stevens serial number lookup.
As of Python 2.7 unittest also includes its own test discovery mechanisms.
Doctest¶
The doctest
module searches for pieces of text that look like interactivePython sessions in docstrings, and then executes those sessions to verify thatthey work exactly as shown.
Doctests have a different use case than proper unit tests: they are usuallyless detailed and don’t catch special cases or obscure regression bugs. Theyare useful as an expressive documentation of the main use cases of a module andits components. However, doctests should run automatically each time the fulltest suite runs.
A simple doctest in a function:
When running this module from the command line as in pythonmodule.py
, thedoctests will run and complain if anything is not behaving as described in thedocstrings.
Tools¶
py.test¶
py.test is a no-boilerplate alternative to Python’s standard unittest module.
Despite being a fully-featured and extensible test tool, it boasts a simplesyntax. Creating a test suite is as easy as writing a module with a couple offunctions:
and then running the py.test command:
is far less work than would be required for the equivalent functionality withthe unittest module!
Hypothesis¶
Hypothesis is a library which lets you write tests that are parameterized bya source of examples. It then generates simple and comprehensible examplesthat make your tests fail, letting you find more bugs with less work.
For example, testing lists of floats will try many examples, but report theminimal example of each bug (distinguished exception type and location):
Hypothesis is practical as well as very powerful and will often find bugsthat escaped all other forms of testing. It integrates well with py.test,and has a strong focus on usability in both simple and advanced scenarios.
tox¶
tox is a tool for automating test environment management and testing againstmultiple interpreter configurations.
tox allows you to configure complicated multi-parameter test matrices via asimple INI-style configuration file.
mock¶
unittest.mock
is a library for testing in Python. As of Python 3.3, it isavailable in thestandard library.
For older versions of Python:
It allows you to replace parts of your system under test with mock objects andmake assertions about how they have been used.
For example, you can monkey-patch a method:
To mock classes or objects in a module under test, use the patch
decorator.In the example below, an external search system is replaced with a mock thatalways returns the same result (but only for the duration of the test).
Mock has many other ways with which you can configure and control its behaviour.
See also
In general, pytest is invoked with the command pytest
(see below for other ways to invoke pytest). This will execute all tests in all files whose names follow the form test_*.py
or *_test.py
in the current directory and its subdirectories. More generally, pytest follows standard test discovery rules.
Specifying which tests to run¶
Pytest supports several ways to run and select tests from the command-line.
Run tests in a module
Run tests in a directory
Run tests by keyword expressions
This will run tests which contain names that match the given string expression (case-insensitive),which can include Python operators that use filenames, class names and function names as variables.The example above will run TestMyClass.test_something
but not TestMyClass.test_method_simple
.
Run tests by node ids
Each collected test is assigned a unique nodeid
which consist of the module filename followedby specifiers like class names, function names and parameters from parametrization, separated by ::
characters.
To run a specific test within a module:
Another example specifying a test method in the command line:
Run tests by marker expressions
Will run all tests which are decorated with the @pytest.mark.slow
decorator.
For more information see marks.
Run tests from packages
This will import pkg.testing
and use its filesystem location to find and run tests from.
Getting help on version, option names, environment variables¶
Profiling test execution duration¶
To get a list of the slowest 10 test durations over 1.0s long:
By default, pytest will not show test durations that are too small (<0.005s) unless -vv
is passed on the command-line.
Managing loading of plugins¶
Early loading plugins¶
You can early-load plugins (internal and external) explicitly in the command-line with the -p
option:
Python Install Html Test Runner Tutorial
The option receives a name
parameter, which can be:
A full module dotted name, for example
myproject.plugins
. This dotted name must be importable.The entry-point name of a plugin. This is the name passed to
setuptools
when the plugin isregistered. For example to early-load the pytest-cov plugin you can use:
Disabling plugins¶
To disable loading specific plugins at invocation time, use the -p
optiontogether with the prefix no:
.
Example: to disable loading the plugin doctest
, which is responsible forexecuting doctest tests from text files, invoke pytest like this:
Other ways of calling pytest¶
Calling pytest through python-mpytest
¶
You can invoke testing through the Python interpreter from the command line:
This is almost equivalent to invoking the command line script pytest[..]
directly, except that calling via python
will also add the current directory to sys.path
.
Calling pytest from Python code¶
You can invoke pytest
from Python code directly:
this acts as if you would call “pytest” from the command line.It will not raise SystemExit
but return the exit code instead.You can pass in options and arguments:
You can specify additional plugins to pytest.main
:
Running it will show that MyPlugin
was added and itshook was invoked:
Note
Python Install Html Test Runner Free
Calling pytest.main()
will result in importing your tests and any modulesthat they import. Due to the caching mechanism of python’s import system,making subsequent calls to pytest.main()
from the same process will notreflect changes to those files between the calls. For this reason, makingmultiple calls to pytest.main()
from the same process (in order to re-runtests, for example) is not recommended.