# Collect: Collect tests quickly

This plugin bypasses the actual execution of tests, and instead just collects test names. Fixtures are also bypassed, so running nosetests with the collection plugin enabled should be very quick.

This plugin is useful in combination with the testid plugin (`--with-id`). Run both together to get an indexed list of all tests, which will enable you to run individual tests by index number.

This plugin is also useful for counting tests in a test suite, and making people watching your demo think all of your tests pass.

## Options

`--collect-only```

  Enable collect-only: Collect and output test names only, don’t run any tests. [COLLECT_ONLY]

## Plugin

class `nose.plugins.collect.``CollectOnly`

  Bases: `nose.plugins.base.Plugin`

  Collect and output test names only, don’t run any tests.

  `options`(parser, env)

    Register commandline options.

  `prepareTestCase`(test)

    Replace actual test with dummy that always passes.

  `prepareTestLoader`(loader)

    Install collect-only suite class in TestLoader.

## Source

    """
    This plugin bypasses the actual execution of tests, and instead just collects
    test names. Fixtures are also bypassed, so running nosetests with the
    collection plugin enabled should be very quick.

    This plugin is useful in combination with the testid plugin (``--with-id``).
    Run both together to get an indexed list of all tests, which will enable you to
    run individual tests by index number.

    This plugin is also useful for counting tests in a test suite, and making
    people watching your demo think all of your tests pass.
    """
    from nose.plugins.base import Plugin
    from nose.case import Test
    import logging
    import unittest

    log = logging.getLogger(__name__)

    class CollectOnly(Plugin):
        """
        Collect and output test names only, don't run any tests.
        """
        name = "collect-only"
        enableOpt = 'collect_only'

        def options(self, parser, env):
            """Register commandline options.
            """
            parser.add_option('--collect-only',
                              action='store_true',
                              dest=self.enableOpt,
                              default=env.get('NOSE_COLLECT_ONLY'),
                              help="Enable collect-only: %s [COLLECT_ONLY]" %
                              (self.help()))

        def prepareTestLoader(self, loader):
            """Install collect-only suite class in TestLoader.
            """
            # Disable context awareness
            log.debug("Preparing test loader")
            loader.suiteClass = TestSuiteFactory(self.conf)

        def prepareTestCase(self, test):
            """Replace actual test with dummy that always passes.
            """
            # Return something that always passes
            log.debug("Preparing test case %s", test)
            if not isinstance(test, Test):
                return
            def run(result):
                # We need to make these plugin calls because there won't be
                # a result proxy, due to using a stripped-down test suite
                self.conf.plugins.startTest(test)
                result.startTest(test)
                self.conf.plugins.addSuccess(test)
                result.addSuccess(test)
                self.conf.plugins.stopTest(test)
                result.stopTest(test)
            return run

    class TestSuiteFactory:
        """
        Factory for producing configured test suites.
        """
        def __init__(self, conf):
            self.conf = conf

        def __call__(self, tests=(), **kw):
            return TestSuite(tests, conf=self.conf)

    class TestSuite(unittest.TestSuite):
        """
        Basic test suite that bypasses most proxy and plugin calls, but does
        wrap tests in a nose.case.Test so prepareTestCase will be called.
        """
        def __init__(self, tests=(), conf=None):
            self.conf = conf
            # Exec lazy suites: makes discovery depth-first
            if callable(tests):
                tests = tests()
            log.debug("TestSuite(%r)", tests)
            unittest.TestSuite.__init__(self, tests)

        def addTest(self, test):
            log.debug("Add test %s", test)
            if isinstance(test, unittest.TestSuite):
                self._tests.append(test)
            else:
                self._tests.append(Test(test, config=self.conf))