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Diffstat (limited to 'lib/spack/external/nose/plugins/manager.py')
| -rw-r--r-- | lib/spack/external/nose/plugins/manager.py | 460 |
1 files changed, 460 insertions, 0 deletions
diff --git a/lib/spack/external/nose/plugins/manager.py b/lib/spack/external/nose/plugins/manager.py new file mode 100644 index 0000000000..4d2ed22b6f --- /dev/null +++ b/lib/spack/external/nose/plugins/manager.py @@ -0,0 +1,460 @@ +""" +Plugin Manager +-------------- + +A plugin manager class is used to load plugins, manage the list of +loaded plugins, and proxy calls to those plugins. + +The plugin managers provided with nose are: + +:class:`PluginManager` + This manager doesn't implement loadPlugins, so it can only work + with a static list of plugins. + +:class:`BuiltinPluginManager` + This manager loads plugins referenced in ``nose.plugins.builtin``. + +:class:`EntryPointPluginManager` + This manager uses setuptools entrypoints to load plugins. + +:class:`ExtraPluginsPluginManager` + This manager loads extra plugins specified with the keyword + `addplugins`. + +:class:`DefaultPluginMananger` + This is the manager class that will be used by default. If + setuptools is installed, it is a subclass of + :class:`EntryPointPluginManager` and :class:`BuiltinPluginManager`; + otherwise, an alias to :class:`BuiltinPluginManager`. + +:class:`RestrictedPluginManager` + This manager is for use in test runs where some plugin calls are + not available, such as runs started with ``python setup.py test``, + where the test runner is the default unittest :class:`TextTestRunner`. It + is a subclass of :class:`DefaultPluginManager`. + +Writing a plugin manager +======================== + +If you want to load plugins via some other means, you can write a +plugin manager and pass an instance of your plugin manager class when +instantiating the :class:`nose.config.Config` instance that you pass to +:class:`TestProgram` (or :func:`main` or :func:`run`). + +To implement your plugin loading scheme, implement ``loadPlugins()``, +and in that method, call ``addPlugin()`` with an instance of each plugin +you wish to make available. Make sure to call +``super(self).loadPlugins()`` as well if have subclassed a manager +other than ``PluginManager``. + +""" +import inspect +import logging +import os +import sys +from itertools import chain as iterchain +from warnings import warn +import nose.config +from nose.failure import Failure +from nose.plugins.base import IPluginInterface +from nose.pyversion import sort_list + +try: + import cPickle as pickle +except: + import pickle +try: + from cStringIO import StringIO +except: + from StringIO import StringIO + + +__all__ = ['DefaultPluginManager', 'PluginManager', 'EntryPointPluginManager', + 'BuiltinPluginManager', 'RestrictedPluginManager'] + +log = logging.getLogger(__name__) + + +class PluginProxy(object): + """Proxy for plugin calls. Essentially a closure bound to the + given call and plugin list. + + The plugin proxy also must be bound to a particular plugin + interface specification, so that it knows what calls are available + and any special handling that is required for each call. + """ + interface = IPluginInterface + def __init__(self, call, plugins): + try: + self.method = getattr(self.interface, call) + except AttributeError: + raise AttributeError("%s is not a valid %s method" + % (call, self.interface.__name__)) + self.call = self.makeCall(call) + self.plugins = [] + for p in plugins: + self.addPlugin(p, call) + + def __call__(self, *arg, **kw): + return self.call(*arg, **kw) + + def addPlugin(self, plugin, call): + """Add plugin to my list of plugins to call, if it has the attribute + I'm bound to. + """ + meth = getattr(plugin, call, None) + if meth is not None: + if call == 'loadTestsFromModule' and \ + len(inspect.getargspec(meth)[0]) == 2: + orig_meth = meth + meth = lambda module, path, **kwargs: orig_meth(module) + self.plugins.append((plugin, meth)) + + def makeCall(self, call): + if call == 'loadTestsFromNames': + # special case -- load tests from names behaves somewhat differently + # from other chainable calls, because plugins return a tuple, only + # part of which can be chained to the next plugin. + return self._loadTestsFromNames + + meth = self.method + if getattr(meth, 'generative', False): + # call all plugins and yield a flattened iterator of their results + return lambda *arg, **kw: list(self.generate(*arg, **kw)) + elif getattr(meth, 'chainable', False): + return self.chain + else: + # return a value from the first plugin that returns non-None + return self.simple + + def chain(self, *arg, **kw): + """Call plugins in a chain, where the result of each plugin call is + sent to the next plugin as input. The final output result is returned. + """ + result = None + # extract the static arguments (if any) from arg so they can + # be passed to each plugin call in the chain + static = [a for (static, a) + in zip(getattr(self.method, 'static_args', []), arg) + if static] + for p, meth in self.plugins: + result = meth(*arg, **kw) + arg = static[:] + arg.append(result) + return result + + def generate(self, *arg, **kw): + """Call all plugins, yielding each item in each non-None result. + """ + for p, meth in self.plugins: + result = None + try: + result = meth(*arg, **kw) + if result is not None: + for r in result: + yield r + except (KeyboardInterrupt, SystemExit): + raise + except: + exc = sys.exc_info() + yield Failure(*exc) + continue + + def simple(self, *arg, **kw): + """Call all plugins, returning the first non-None result. + """ + for p, meth in self.plugins: + result = meth(*arg, **kw) + if result is not None: + return result + + def _loadTestsFromNames(self, names, module=None): + """Chainable but not quite normal. Plugins return a tuple of + (tests, names) after processing the names. The tests are added + to a suite that is accumulated throughout the full call, while + names are input for the next plugin in the chain. + """ + suite = [] + for p, meth in self.plugins: + result = meth(names, module=module) + if result is not None: + suite_part, names = result + if suite_part: + suite.extend(suite_part) + return suite, names + + +class NoPlugins(object): + """Null Plugin manager that has no plugins.""" + interface = IPluginInterface + def __init__(self): + self._plugins = self.plugins = () + + def __iter__(self): + return () + + def _doNothing(self, *args, **kwds): + pass + + def _emptyIterator(self, *args, **kwds): + return () + + def __getattr__(self, call): + method = getattr(self.interface, call) + if getattr(method, "generative", False): + return self._emptyIterator + else: + return self._doNothing + + def addPlugin(self, plug): + raise NotImplementedError() + + def addPlugins(self, plugins): + raise NotImplementedError() + + def configure(self, options, config): + pass + + def loadPlugins(self): + pass + + def sort(self): + pass + + +class PluginManager(object): + """Base class for plugin managers. PluginManager is intended to be + used only with a static list of plugins. The loadPlugins() implementation + only reloads plugins from _extraplugins to prevent those from being + overridden by a subclass. + + The basic functionality of a plugin manager is to proxy all unknown + attributes through a ``PluginProxy`` to a list of plugins. + + Note that the list of plugins *may not* be changed after the first plugin + call. + """ + proxyClass = PluginProxy + + def __init__(self, plugins=(), proxyClass=None): + self._plugins = [] + self._extraplugins = () + self._proxies = {} + if plugins: + self.addPlugins(plugins) + if proxyClass is not None: + self.proxyClass = proxyClass + + def __getattr__(self, call): + try: + return self._proxies[call] + except KeyError: + proxy = self.proxyClass(call, self._plugins) + self._proxies[call] = proxy + return proxy + + def __iter__(self): + return iter(self.plugins) + + def addPlugin(self, plug): + # allow, for instance, plugins loaded via entry points to + # supplant builtin plugins. + new_name = getattr(plug, 'name', object()) + self._plugins[:] = [p for p in self._plugins + if getattr(p, 'name', None) != new_name] + self._plugins.append(plug) + + def addPlugins(self, plugins=(), extraplugins=()): + """extraplugins are maintained in a separate list and + re-added by loadPlugins() to prevent their being overwritten + by plugins added by a subclass of PluginManager + """ + self._extraplugins = extraplugins + for plug in iterchain(plugins, extraplugins): + self.addPlugin(plug) + + def configure(self, options, config): + """Configure the set of plugins with the given options + and config instance. After configuration, disabled plugins + are removed from the plugins list. + """ + log.debug("Configuring plugins") + self.config = config + cfg = PluginProxy('configure', self._plugins) + cfg(options, config) + enabled = [plug for plug in self._plugins if plug.enabled] + self.plugins = enabled + self.sort() + log.debug("Plugins enabled: %s", enabled) + + def loadPlugins(self): + for plug in self._extraplugins: + self.addPlugin(plug) + + def sort(self): + return sort_list(self._plugins, lambda x: getattr(x, 'score', 1), reverse=True) + + def _get_plugins(self): + return self._plugins + + def _set_plugins(self, plugins): + self._plugins = [] + self.addPlugins(plugins) + + plugins = property(_get_plugins, _set_plugins, None, + """Access the list of plugins managed by + this plugin manager""") + + +class ZeroNinePlugin: + """Proxy for 0.9 plugins, adapts 0.10 calls to 0.9 standard. + """ + def __init__(self, plugin): + self.plugin = plugin + + def options(self, parser, env=os.environ): + self.plugin.add_options(parser, env) + + def addError(self, test, err): + if not hasattr(self.plugin, 'addError'): + return + # switch off to addSkip, addDeprecated if those types + from nose.exc import SkipTest, DeprecatedTest + ec, ev, tb = err + if issubclass(ec, SkipTest): + if not hasattr(self.plugin, 'addSkip'): + return + return self.plugin.addSkip(test.test) + elif issubclass(ec, DeprecatedTest): + if not hasattr(self.plugin, 'addDeprecated'): + return + return self.plugin.addDeprecated(test.test) + # add capt + capt = test.capturedOutput + return self.plugin.addError(test.test, err, capt) + + def loadTestsFromFile(self, filename): + if hasattr(self.plugin, 'loadTestsFromPath'): + return self.plugin.loadTestsFromPath(filename) + + def addFailure(self, test, err): + if not hasattr(self.plugin, 'addFailure'): + return + # add capt and tbinfo + capt = test.capturedOutput + tbinfo = test.tbinfo + return self.plugin.addFailure(test.test, err, capt, tbinfo) + + def addSuccess(self, test): + if not hasattr(self.plugin, 'addSuccess'): + return + capt = test.capturedOutput + self.plugin.addSuccess(test.test, capt) + + def startTest(self, test): + if not hasattr(self.plugin, 'startTest'): + return + return self.plugin.startTest(test.test) + + def stopTest(self, test): + if not hasattr(self.plugin, 'stopTest'): + return + return self.plugin.stopTest(test.test) + + def __getattr__(self, val): + return getattr(self.plugin, val) + + +class EntryPointPluginManager(PluginManager): + """Plugin manager that loads plugins from the `nose.plugins` and + `nose.plugins.0.10` entry points. + """ + entry_points = (('nose.plugins.0.10', None), + ('nose.plugins', ZeroNinePlugin)) + + def loadPlugins(self): + """Load plugins by iterating the `nose.plugins` entry point. + """ + from pkg_resources import iter_entry_points + loaded = {} + for entry_point, adapt in self.entry_points: + for ep in iter_entry_points(entry_point): + if ep.name in loaded: + continue + loaded[ep.name] = True + log.debug('%s load plugin %s', self.__class__.__name__, ep) + try: + plugcls = ep.load() + except KeyboardInterrupt: + raise + except Exception, e: + # never want a plugin load to kill the test run + # but we can't log here because the logger is not yet + # configured + warn("Unable to load plugin %s: %s" % (ep, e), + RuntimeWarning) + continue + if adapt: + plug = adapt(plugcls()) + else: + plug = plugcls() + self.addPlugin(plug) + super(EntryPointPluginManager, self).loadPlugins() + + +class BuiltinPluginManager(PluginManager): + """Plugin manager that loads plugins from the list in + `nose.plugins.builtin`. + """ + def loadPlugins(self): + """Load plugins in nose.plugins.builtin + """ + from nose.plugins import builtin + for plug in builtin.plugins: + self.addPlugin(plug()) + super(BuiltinPluginManager, self).loadPlugins() + +try: + import pkg_resources + class DefaultPluginManager(EntryPointPluginManager, BuiltinPluginManager): + pass + +except ImportError: + class DefaultPluginManager(BuiltinPluginManager): + pass + +class RestrictedPluginManager(DefaultPluginManager): + """Plugin manager that restricts the plugin list to those not + excluded by a list of exclude methods. Any plugin that implements + an excluded method will be removed from the manager's plugin list + after plugins are loaded. + """ + def __init__(self, plugins=(), exclude=(), load=True): + DefaultPluginManager.__init__(self, plugins) + self.load = load + self.exclude = exclude + self.excluded = [] + self._excludedOpts = None + + def excludedOption(self, name): + if self._excludedOpts is None: + from optparse import OptionParser + self._excludedOpts = OptionParser(add_help_option=False) + for plugin in self.excluded: + plugin.options(self._excludedOpts, env={}) + return self._excludedOpts.get_option('--' + name) + + def loadPlugins(self): + if self.load: + DefaultPluginManager.loadPlugins(self) + allow = [] + for plugin in self.plugins: + ok = True + for method in self.exclude: + if hasattr(plugin, method): + ok = False + self.excluded.append(plugin) + break + if ok: + allow.append(plugin) + self.plugins = allow |