How to use rewrite_asserts method in Pytest

Best Python code snippet using pytest

_pytest_support.py

Source:_pytest_support.py

...185        from _pytest.assertion.rewrite import rewrite_asserts186        pytest_version = get_pytest_version()187        if pytest_version.release[0] >= 5:188            # TODO: re-create a pseudo code to include the asserts?189            rewrite_asserts(node, b"")190        else:191            rewrite_asserts(node)192        return node193def get_pytest_version():194    return packaging.version.parse(pytest.__version__)195@magics_class196class IPyTestMagics(Magics):197    @cell_magic("run_pytest[clean]")198    def run_pytest_clean(self, line, cell):199        import __main__200        clean_tests(items=__main__.__dict__)201        return self.run_pytest(line, cell)202    @cell_magic203    def run_pytest(self, line, cell):204        # If config.rewrite_asserts is True assertions are being205        # rewritten by default, do not re-rewrite them.206        if not config.rewrite_asserts:207            self.rewrite_asserts(line, cell)208        else:209            self.shell.run_cell(cell)210        import ipytest211        ipytest.exit_code = run(*shlex.split(line), return_exit_code=True)212    @cell_magic213    def rewrite_asserts(self, line, cell):214        """Rewrite asserts with pytest.215        Usage::216            %%rewrite_asserts217            ...218            # new cell:219            from ipytest import run_pytest220            run_pytest()221        """222        if config.rewrite_asserts:223            warnings.warn("skip rewriting as global rewriting is active")224            return225        with RewriteContext(get_ipython()):...

_config.py

Source:_config.py

...103        key: replace_with_default(keep, args[key], current_config.get(key))104        for key in current_config105    }106    if new_config["rewrite_asserts"] != current_config["rewrite_asserts"]:107        configure_rewrite_asserts(new_config["rewrite_asserts"])108    if new_config["magics"] != current_config["magics"]:109        configure_magics(new_config["magics"])110    current_config.update(new_config)111    return dict(current_config)112def configure_rewrite_asserts(enable):113    global _rewrite_transformer114    from IPython import get_ipython115    from ._impl import RewriteAssertTransformer116    shell = get_ipython()117    if enable:118        assert _rewrite_transformer is None119        _rewrite_transformer = RewriteAssertTransformer()120        _rewrite_transformer.register_with_shell(shell)121    else:122        assert _rewrite_transformer is not None123        _rewrite_transformer.unregister_with_shell(shell)124        _rewrite_transformer = None125def configure_magics(enable):126    from IPython import get_ipython...

apptest2.py

Source:apptest2.py

...29                                """(rootdir, source, fname, name):30                import sys31                sys.path.insert(0, rootdir)32                from ast_rewrite import rewrite_asserts, create_module33                co = rewrite_asserts(source, fname)34                mod = create_module(name, co)35                return mod36            """)37        else:38            w_mod = create_module(space, w_name, fname, source)39        mod_dict = w_mod.getdict(space).unwrap(space)40        items = []41        for name, w_obj in mod_dict.items():42            if not name.startswith('test_'):43                continue44            if not isinstance(w_obj, pypy.interpreter.function.Function):45                continue46            items.append(AppTestFunction(name, self, w_obj))47        items.sort(key=lambda item: item.reportinfo()[:2])...

__init__.py

Source:__init__.py

...86    except SyntaxError:87        # Let this pop up again in the real import.88        mod.config._assertstate.trace("failed to parse: %r" % (mod.fspath,))89        return90    rewrite_asserts(tree)91    try:92        co = compile(tree, str(mod.fspath), "exec")93    except SyntaxError:94        # It's possible that this error is from some bug in the assertion95        # rewriting, but I don't know of a fast way to tell.96        mod.config._assertstate.trace("failed to compile: %r" % (mod.fspath,))97        return98    mod._pyc = _write_pyc(co, mod.fspath)99    mod.config._assertstate.trace("wrote pyc: %r" % (mod._pyc,))100def after_module_import(mod):101    if not hasattr(mod, "_pyc"):102        return103    state = mod.config._assertstate104    try:...

Pytest Tutorial

Looking for an in-depth tutorial around pytest? LambdaTest covers the detailed pytest tutorial that has everything related to the pytest, from setting up the pytest framework to automation testing. Delve deeper into pytest testing by exploring advanced use cases like parallel testing, pytest fixtures, parameterization, executing multiple test cases from a single file, and more.

Chapters

What is pytest
Pytest installation: Want to start pytest from scratch? See how to install and configure pytest for Python automation testing.
Run first test with pytest framework: Follow this step-by-step tutorial to write and run your first pytest script.
Parallel testing with pytest: A hands-on guide to parallel testing with pytest to improve the scalability of your test automation.
Generate pytest reports: Reports make it easier to understand the results of pytest-based test runs. Learn how to generate pytest reports.
Pytest Parameterized tests: Create and run your pytest scripts while avoiding code duplication and increasing test coverage with parameterization.
Pytest Fixtures: Check out how to implement pytest fixtures for your end-to-end testing needs.
Execute Multiple Test Cases: Explore different scenarios for running multiple test cases in pytest from a single file.
Stop Test Suite after N Test Failures: See how to stop your test suite after n test failures in pytest using the @pytest.mark.incremental decorator and maxfail command-line option.