How to use pytest_runtestloop method in Pytest

Best Python code snippet using pytest

scheduler.py

Source:scheduler.py

...8level. For instance, all performance tests will run sequentially9(i.e. concurrency=1), since they rely on the availability of the full host10resources, in order to make accurate measurements. Additionally, other tests11may be restricted to running sequentially, if they are per se12concurrency-unsafe. See `PytestScheduler.pytest_runtestloop()`.13Scheduling is achieved by overriding the pytest run loop (i.e.14`pytest_runtestloop()`), and splitting the test session item list across15multiple `fork()`ed worker processes. Since no user code is run before16`pytest_runtestloop()`, each worker becomes a pytest session itself.17Reporting is disabled for worker process, each worker sending its results18back to the main / server process, via an IPC pipe, for aggregation.19"""20import multiprocessing as mp21import os22import re23import sys24from random import random25from select import select26from time import sleep27import pytest28from _pytest.main import ExitCode29from . import mpsing  # pylint: disable=relative-beyond-top-level30class PytestScheduler(mpsing.MultiprocessSingleton):31    """A pretty custom test execution scheduler."""32    def __init__(self):33        """Initialize the scheduler.34        Not to be called directly, since this is a singleton. Use35        `PytestScheduler.instance()` to get the scheduler object.36        """37        super().__init__()38        self._mp_singletons = [self]39        self.session = None40    def register_mp_singleton(self, mp_singleton):41        """Register a multi-process singleton object.42        Since the scheduler will be handling the main testing loop, it needs43        to be aware of any multi-process singletons that must be serviced44        during the test run (i.e. polled and allowed to handle method45        execution in the server context).46        """47        self._mp_singletons.append(mp_singleton)48    @staticmethod49    def do_pytest_addoption(parser):50        """Pytest hook. Add concurrency command line option."""51        avail_cpus = len(os.sched_getaffinity(0))52        # Defaulting to a third of the available (logical) CPUs sounds like a53        # good enough plan.54        default = max(1, int(avail_cpus / 3))55        parser.addoption(56            "--concurrency",57            "--concurrency",58            dest="concurrency",59            action="store",60            type=int,61            default=default,62            help="Concurrency level (max number of worker processes to spawn)."63        )64    def pytest_sessionstart(self, session):65        """Pytest hook. Called at pytest session start.66        This will execute in the server context (before the tests are67        executed).68        """69        self.session = session70    def pytest_runtest_logreport(self, report):71        """Pytest hook. Called whenever a new test report is ready.72        This will execute in the worker / child context.73        """74        self._add_report(report)75    def pytest_runtestloop(self, session):76        """Pytest hook. The main test scheduling and running loop.77        Called in the server process context.78        """79        # Don't run tests on test discovery80        if session.config.option.collectonly:81            return True82        # max_concurrency = self.session.config.option.concurrency83        schedule = [84            {85                # Performance batch: tests that measure performance, and need86                # to be run in a non-cuncurrent environment.87                'name': 'performance',88                'concurrency': 1,89                'patterns': [...

spydist.py

Source:spydist.py

...81        self.thread = threading.Thread(target=self.server.start)82        self.thread.start()83    def pytest_sessionfinish(self, session):84        debug("master: pytest_sessionfinish", session)85    def pytest_runtestloop(self):86        if wa.start_slaves_from_master:87            slaves_init(self.logs_path)88        try:89            conn = rpyc.connect("127.0.0.1", self.port)90            while 1:91                if not getattr(conn.root, "has_pending")():92                    break93                debug("master: pytest_runtestloop")94                time.sleep(5)95        except KeyboardInterrupt:96            trace("master: interrupted")97            getattr(conn.root, "shutdown")()98            time.sleep(5)99        os._exit(0)100    def pytest_terminal_summary(self, terminalreporter):101        debug("master: pytest_terminal_summary", terminalreporter)102class BatchSlave(object):103    def __init__(self, config, logs_path):104        self.config = config105        self.items = []106        self.logs_path = logs_path107    @pytest.mark.trylast108    def pytest_sessionstart(self, session):109        debug("slave: pytest_sessionstart", session)110    def pytest_sessionfinish(self, session):111        debug("slave: pytest_sessionfinish", session)112    @pytest.hookimpl(trylast=True)113    def pytest_collection_modifyitems(self, session, config, items):114        debug("slave: pytest_collection_modifyitems", session, config, items)115        self.items = items116    def pytest_runtestloop(self):117        def search_nodeid(entries, nodeid):118            for ent in entries:119                if nodeid == ent.nodeid:120                    return ent121            return None122        def finish_test(item):123            getattr(conn.root, "finish_test")(item.nodeid)124        def get_test(entries):125            while 1:126                nodeid = getattr(conn.root, "get_test")()127                if not nodeid:128                    break129                item = search_nodeid(entries, nodeid)130                if item:...

pydev_runfiles_pytest.py

Source:pydev_runfiles_pytest.py

...91        if hasattr(config.option, 'numprocesses'):92            if config.option.numprocesses:93                self._using_xdist = True94                pydev_runfiles_xml_rpc.notifyTestRunFinished('Unable to show results (py.test xdist plugin not compatible with PyUnit view)')95    def pytest_runtestloop(self, session):96        if self._using_xdist:97            #Yes, we don't have the hooks we'd need to show the results in the pyunit view...98            #Maybe the plugin maintainer may be able to provide these additional hooks?99            return None100        101        #This mock will make all file representations to be printed as Pydev expects, 102        #so that hyperlinks are properly created in errors. Note that we don't unmock it!103        self._MockFileRepresentation()104        105        #Based on the default run test loop: _pytest.session.pytest_runtestloop106        #but getting the times we need, reporting the number of tests found and notifying as each107        #test is run.108        109        start_total = time.time()...

plugin.py

Source:plugin.py

...27        action="store_true",28        dest="find_dependencies_internal",29        help="""For internal use only""",30    )31def pytest_runtestloop(session):32    if session.config.getoption("find_dependencies_internal"):33        return run_tests(session)34    if not session.config.getoption("find_dependencies"):35        return pytest_main.pytest_runtestloop(session)36    if len(session.items) == 1:37        print("Only one test collected: ignoring option --find-dependencies")38        restore_verbosity(session.config)39        return pytest_main.pytest_runtestloop(session)40    if (session.testsfailed and41            not session.config.option.continue_on_collection_errors):42        restore_verbosity(session.config)43        raise session.Interrupted(44            "%d errors during collection" % session.testsfailed)45    DependencyFinder(session).find_dependencies()46    return True47def restore_verbosity(config):48    verbosity = 049    if hasattr(config, "initial_args"):50        for arg in config.initial_args:51            if arg.startswith("-v"):52                verbosity = len(arg) - 153                break...

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