Mailman 3 August 2010 - Python-Dev

release26-maint semi-frozen
by Barry Warsaw 03 Aug '10

03 Aug '10

We're going to go ahead and cut the 2.6.6rc1 release tonight, bugs.python.org willing. We've got a fairly clean test run on local hardware across OS X, Linux (Debian, Ubuntu), and Brian is looking at Windows now (the buildbots are a sad and sorry story). Ezio has done a great amount of work on getting 2.6.6 pretty clean with -3 warnings too. Please consider the release26-maint tree closed for commits (except svnmerges) for the next 2.5 hours. I'll send another message at about 2200 UTC when I freeze the tree for those commits too. You can request exceptions by pinging me on #python-dev or (if you're feeling lucky ;) sending me an email. -Barry

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No response to posts
by Mark Lawrence 03 Aug '10

03 Aug '10

Hi all, I have been wading through outstanding issues today and have noticed that there are several where there has been no response at all to the initial post. Failing that, the only response has been Terry Reedy back in May 2010, and that only updating the versions affected. Would it be possible to get some code in place whereby if there is no response to the initial post, this could be flagged up after (say) 24 hours? Surely any response back to the OP is better than a complete wall of silence? Kindest regards. Mark Lawrence.

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PEP 376 proposed changes for basic plugins support
by Tarek Ziadé 03 Aug '10

03 Aug '10

Hello, Here's a proposal to extend PEP 376 to support a basic plugins feature -- you should read PEP 376 before reading this mail It's basically Phillip's entry points, but with an activation flag, and a per-user config file. = adding a PLUGINS file = A new file called 'PLUGINS' is added to the dist-info directory at install time, and contains a list of plugins for the installed distribution. The file is a CSV file like the RECORD file, containing one plugin per line. (see the RECORD file for details on the syntax) A plugin is defined by : - an application name : a string containing a name of a group of plugins. It can be the name of the application that supports plugins, or any string. The recommended value is the distutils name of the project, as it appears at PyPI. max length: 64, chars: [a-z0-9] - a plugin type name: a string containing a name of a type of plugins. It can be combined with the application name to create one class of plugins for a given application. 64 chars [a-z0-9] -- default value 'plugin' - a name: a string containing a name for the plugin. Combined with the application name and plugin type, it defines this plugin. 64 chars [a-z0-9] - a description: a string describing the plugin. 256 chars. - a state: 1 or 0. 1 means the plugin is activated, 0 means it's not activated - a code link: a link to the plugin object (whether its a module, class, object, etc). This link is the complete import path. For example, a plugin class called "Foo" located in the "bar" module, located in the "baz" package, is noted: "baz.bar.Foo" (the project that uses plugins is responsible for iteratting, picking and loading plugins) = PLUGINS example = Here's an example of a PLUGINS file for a 'UnittestPlugins' project that implements 2 unitest2 plugins: unittest2;plugin;pep8;pep8 checker;1;unittestplugins.pep8 unittest2;plugin;debugger,Cool debugger;1;unittestplugins.debug = per-user plugins = A plugin can be activated or disable globally, but a user should be able to configure them differently. A ini-like plugins.cfg file is added per-user (its location to be defined -- its discussed in another thread) and overrides the state of the installed plugin. It provides a value for each app.type.name plugin. [plugins] unittest2.plugin.pep8 = 0 distutils2.commands.funkycommand = 0 Notice that the user can have plugins provided by distributions installed in his own per-user site packages. = Implementation = I don't want to go into great details here yet, until we get a consensus on the PLUGINS file. But basically we will add these features in pkgutil: - browse plugins and get their info. - activate/disable a plugin, by writing its state - load a plugin and return it by importing the 'code link' and in distutils2: - let the user configure if plugins are automatically activated when the project is installed - provide a end-user script to browse plugins - provide a way to define plugins statically in setup.cfg Regards Tarek -- Tarek Ziadé | http://ziade.org

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logging package vs unicode
by Chris Withers 03 Aug '10

03 Aug '10

Hi All, The documentation for the logging package doesn't include any mention of unicode. What's the recommended usage in terms of passing unicode vs encoded strings? How does this differ from Python 2 to Python 3? cheers, Chris -- Simplistix - Content Management, Batch Processing & Python Consulting - http://www.simplistix.co.uk

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Re: [Python-Dev] PEP 382 progress: import hooks
by P.J. Eby 03 Aug '10

03 Aug '10

At 05:28 PM 8/2/2010 -0700, Brett Cannon wrote: >On Fri, Jul 23, 2010 at 09:54, P.J. Eby ><<mailto:pje@telecommunity.com>pje(a)telecommunity.com> wrote: >At 11:57 AM 7/23/2010 +0100, Brett Cannon wrote: > > > >On Thu, Jul 22, 2010 at 19:19, P.J. Eby ><<mailto:pje@telecommunity.com>pje(a)telecommunity.com> wrote: > >What does "is not a package" actually mean in that context? > > >The module is a module but not a package. > > >Um... Â that's not any clearer. Â Are you saying that a module of >the same name takes precedence over a package? Â Is that the current >precedence as well? > > >No, packages take precedence. I meant that something is a module but >it is not a package; a package implicitly includes a module, but a >module is not automatically a package. That explanation still isn't making things any clearer for me. That is, I don't know how to get from that statement to actual code, even if I were writing a filesystem or zip importer, let alone anything more exotic. > zipimport also does it this way as it too does not differentiate a > reload from a clean load beyond grabbing the module from > sys.modules if it is already there. PEP 302 does not directly state > that reloading should not reset the attributes that import must > set, simply that a module from sys.modules must be reused. Since > zipimport does it this way I wouldn't count on other loaders not > setting __path__. Fair enough, though certainly unfortunate. In particular, it means that it's not actually possible to correctly/completely implement PEP 382 on any already-released version of Python, without essentially replacing zipimport. (Unless the spec can be tweaked a bit.) >I'm personally not worried about supporting older versions of Python >as this is a new feature. Better to design it properly than come up >with some hack solution as we will all have to live with this for a long time. Currently, older Pythons are the only versions I *do* support, so I'm very concerned with it. Otherwise, I'd not be asking all these questions. ;-) Personally, I think there are features in the PEP that make things unnecessarily complicated - for example, supporting both __init__.py *and* .pth files in the same directory. If it were either/or, it would be a LOT easier to implement on older Pythons, since it wouldn't matter when you initialized the __path__ in that case. (By the way, there were some other questions I asked about the PEP 382 revisions, that you didn't reply to in previous emails (such as the format of the strings to be returned by find_path()); I hope either you or Martin can fill those in for me, and hopefully update the PEP with the things we have talked about in this thread.)

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Re: [Python-Dev] [Python-checkins] r83596 - in python/branches/release26-maint: Doc/library/constants.rst
by Ezio Melotti 03 Aug '10

03 Aug '10

Hi, On 03/08/2010 0.47, georg.brandl wrote: > Author: georg.brandl > Date: Mon Aug 2 23:47:02 2010 > New Revision: 83596 > > Log: > Merged revisions 83567 via svnmerge from > svn+ssh://pythondev@svn.python.org/python/branches/release27-maint > > ................ > r83567 | georg.brandl | 2010-08-02 22:32:03 +0200 (Mo, 02 Aug 2010) | 9 lines > > Merged revisions 83552 via svnmerge from > svn+ssh://pythondev@svn.python.org/python/branches/py3k > > ........ > r83552 | georg.brandl | 2010-08-02 21:36:36 +0200 (Mo, 02 Aug 2010) | 1 line > > #9438: clarify that constant names also cannot be assigned as attributes. > ........ > ................ > > > Modified: > python/branches/release26-maint/ (props changed) > python/branches/release26-maint/Doc/library/constants.rst > > Modified: python/branches/release26-maint/Doc/library/constants.rst > ============================================================================== > --- python/branches/release26-maint/Doc/library/constants.rst (original) > +++ python/branches/release26-maint/Doc/library/constants.rst Mon Aug 2 23:47:02 2010 > @@ -3,7 +3,6 @@ > > A small number of constants live in the built-in namespace. They are: > > - > .. data:: False > > The false value of the :class:`bool` type. > @@ -39,16 +38,23 @@ > > Special value used in conjunction with extended slicing syntax. > > - .. XXX Someone who understands extended slicing should fill in here. > - > > .. data:: __debug__ > > This constant is true if Python was not started with an :option:`-O` option. > - Assignments to :const:`__debug__` are illegal and raise a :exc:`SyntaxError`. > See also the :keyword:`assert` statement. > > > +.. note:: > + > + The names :data:`None` and :data:`__debug__` cannot be reassigned > + (assignments to them, even as an attribute name, raise :exc:`SyntaxError`), > + so they can be considered "true" constants. > + > + .. versionchanged:: 2.7 > + Assignments to ``__debug__`` as an attribute became illegal. this shouldn't be here. > + > + > Constants added by the :mod:`site` module > ----------------------------------------- > > _______________________________________________ > Python-checkins mailing list > Python-checkins(a)python.org > http://mail.python.org/mailman/listinfo/python-checkins > Best Regards, Ezio Melotti

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Re: [Python-Dev] [Python-checkins] r83543 - python/branches/py3k/Lib/test/regrtest.py
by R. David Murray 03 Aug '10

03 Aug '10

On Mon, 02 Aug 2010 20:59:52 +0200, georg.brandl <python-checkins(a)python.org> wrote: > Author: georg.brandl > Date: Mon Aug 2 20:59:52 2010 > New Revision: 83543 > > Log: > #8560: add progress indicator to regrtest. [...] > @@ -517,6 +517,9 @@ > else: > tests = iter(selected) > > + tests = list(tests) I guess you didn't notice that just above this code is a clause that says 'if forever' which implements -F/--forever by making tests into a generator that never runs out... -- R. David Murray www.bitdance.com

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Postponing 2.6.6rc1
by Barry Warsaw 03 Aug '10

03 Aug '10

For several reasons, I'm postponing 2.6.6rc1 for one day. Ezio has been doing a lot of great work on the test suite, but there are still a few things to fix. On top of that, bugs.python.org crashed and we're waiting for our hosting company to wake up and reboot it. We'll try again, same time tomorrow: 2200 UTC. Come join us on #python-dev if you want to watch the circus. :) -Barry

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proto-pep: plugin proposal (for unittest)
by Michael Foord 03 Aug '10

03 Aug '10

Hello all, My apologies in advance if email mangles whitespace in the code examples. I can reformulate as a PEP if that is deemed useful and this document can be found online at: http://hg.python.org/unittest2/file/tip/description.txt (Please excuse errors and omissions - but do feel free to point them out.) This is a description, and request for feedback, of the unittest plugin system that I am currently prototyping in the plugins branch of unittest2_. My goal is to merge the plugin system back into unittest itself in Python 3.2. .. _unittest2: http://hg.python.org/unittest2 As part of the prototype I have been implementing some example plugins (in unittest2/plugins/) so I can develop the mechanism against real rather than imagined use cases. Jason Pellerin, creator of nose, has been providing me with feedback and has been trying it out by porting some of the nose plugins to unittest [#]_. He comments on the system "it looks very flexible and clean". ;-) Example plugins available and included: * a pep8 and pyflakes checker * a debugger plugin that drops you into pdb on test fail / error * a doctest loader (looks for doctests in all text files in the project) * use a regex for matching files in test discovery instead of a glob * growl notifications on test run start and stop * filter individual *test methods* using a regex * load test functions from modules as well as TestCases * integration with the coverage module for coverage reporting In addition I intend to create a plugin that outputs junit compatible xml from a test run (for integration with tools like the hudson continuous integration server) and a test runner that runs tests in parallel using multiprocessing. Not all of these will be included in the merge to unittest. Which ones will is still an open question. I'd like feedback on the proposal, and hopefully approval to port it into unittest after discussion / amendment / completion. In particular I'd like feedback on the basic system, plus which events should be available and what information should be available in them. Note that the system is *not* complete in the prototype. Enough is implemented to get "the general idea" and to formalise the full system. It still needs extensive tests and the extra work in TestProgram makes it abundantly clear that refactoring there is well overdue... In the details below open questions and todos are noted. I *really* value feedback (but will ignore bikeshedding ;-) .. note:: Throughout this document I refer to the prototype implementation using names like ``unittest2.events.hooks``. Should this proposal be accepted then the names will live in the unittest package instead of unittest2. The core classes for the event system live in the current implementation in the ``unittest2.events`` namespace. Abstract ======== unittest lacks a standard way of extending it to provide commonly requested functionality, other than subclassing and overriding (and reimplementing) parts of its behaviour. This document describes a plugin system already partially prototyped in unittest2. Aspects of the plugin system include: * an events mechanism where handlers can be registered and called during a test run * a Plugin class built over the top of this for easy creation of plugins * a configuration system for specifying which plugins should be loaded and for configuring individual plugins * command line integration * the specific set of events and the information / actions available to them As the plugin system essentially just adds event calls to key places it has few backwards compatibility issues. Unfortunately existing extensions that override the parts of unittest that call these events will not be compatible with plugins that use them. Framework authors who re-implement parts of unittest, for example custom test runners, may want to add calling these events in appropriate places. Rationale ========= Why a plugin system for unittest? unittest is the standard library test framework for Python but in recent years has been eclipsed in functionality by frameworks like nose and py.test. Among the reasons for this is that these frameworks are easier to extend with plugins than unittest. unittest makes itself particularly difficult to extend by using subclassing as its basic extension mechanism. You subclass and override behaviour in its core classes like the loader, runner and result classes. This means that where you have more than one "extension" working in the same area it is very hard for them to work together. Whilst various extensions to unittest do exist (e.g. testtools, zope.testrunner etc) they don't tend to work well together. In contrast the plugin system makes creating extensions to unittest much simpler and less likely that extensions will clash with each other. nose itself exists as a large system built over the top of unittest. Extending unittest in this way was very painful for the creators of nose, and every release of Python breaks nose in some way due to changes in unittest. One of the goals of the extension mechanism is to allow nose2 to be a much thinner set of plugins over unittest(2) that is much simpler to maintain [#]_. The early indications are that the proposed system is a good fit for this goal. Low Level Mechanism ==================== The basic mechanism is having events fired at various points during a test run. Plugins can register event handler functions that will be called with an event object. Multiple functions may be registered to handle an event and event handlers can also be removed. Over the top of this is a ``Plugin`` class that simplifies building plugins on top of this mechanism. This is described in a separate section. The events live on the ``unittest2.events.hooks`` class. Handlers are added using ``+=`` and removed using ``-=``, a syntax borrowed from the .NET system. For example adding a handler for the ``startTestRun`` event:: from unittest2.events import hooks def startTestRun(event): print 'test run started at %s' % event.startTime hooks.startTestRun += startTestRun Handlers are called with an Event object specific to the event. Each event provides different information on its event objects as attributes. For example the attributes available on ``StartTestRunEvent`` objects are: * ``suite`` - the test suite for the full test run * ``runner`` - the test runner * ``result`` - the test result * ``startTime`` The name of events, whether any should be added or removed, and what information is available on the event objects are all valid topics for discussion. Specific events and the information available to them is covered in a section below. An example plugin using events directly is the ``doctestloader`` plugin. Framework authors who re-implement parts of unittest, for example custom test runners, may want to add calling these events in appropriate places. This is very simple. For example the ``pluginsLoaded`` event is fired with a ``PluginsLoadedEvent`` object that is instantiated without parameters:: from unittest2.events import hooks, PluginsLoadedEvent hooks.pluginsLoaded(PluginsLoadedEvent()) Why use event objects and not function parameters? -------------------------------------------------- There are several reasons to use event objects instead of function parameters. The *disadvantage* of this is that the information available to an event is not obvious from the signature of a handler. There are several compelling advantages however: * the signature of all handler functions is identical and therefore easy to remember * backwards compatibility - new attributes can be added to event objects (and parameters deprecated) without breaking existing plugins. Changing the way a function is called (unless all handlers have a ``**kw`` signature) is much harder. * several of the events have a lot of information available. This would make the signature of handlers huge. With an event object handlers only need to be aware of attributes they are interested in and ignore information they aren't interested in ("only pay for what you eat"). * some of the attributes are mutable - the event object is shared between all handlers, this would be less obvious if function parameters were used * calling multiple handlers and still returning a value (see the handled pattern below) The handled pattern -------------------- Several events can be used to *override* the default behaviour. For example the 'matchregexp' plugin uses the ``matchPath`` event to replace the default way of matching files for loading as tests during test discovery. The handler signals that it is handling this event, and the default implementation should not be run, by setting ``event.handled = True``:: def matchRegexp(event): pattern = event.pattern name = event.name event.handled = True path = event.path if matchFullPath: return re.match(pattern, path) return re.match(pattern, name) Where the default implementation returns a value, for example creating a test suite, or in the case of ``matchPath`` deciding if a path matches a file that should be loaded as a test, the handler can return a result. If an event sets handled on an event then no more handlers will be called for that event. Which events can be handled, and which not, is discussed in the events section. The Plugin Class ================ A sometimes-more-convenient way of creating plugins is to subclass the ``unittest2.events.Plugin`` class. By default subclassing ``Plugin`` will auto-instantiate the plugin and store the instance in a list of loaded plugins. Each plugin has a ``register()`` method that auto-hooks up all methods whose names correspond to events. Plugin classes may also provide ``configSection`` and ``commandLineSwitch`` class attributes which simplifies enabling the plugin through the command line and making available a section from the configuration file(s). A simple plugin using this is the 'debugger' plugin that starts ``pdb`` when the ``onTestFail`` event fires:: from unittest2.events import Plugin import pdb import sys class Debugger(Plugin): configSection = 'debugger' commandLineSwitch = ('D', 'debugger', 'Enter pdb on test fail or error') def __init__(self): self.errorsOnly = self.config.as_bool('errors-only', default=False) def onTestFail(self, event): value, tb = event.exc_info[1:] test = event.test if self.errorsOnly and isinstance(value, test.failureException): return original = sys.stdout sys.stdout = sys.__stdout__ try: pdb.post_mortem(tb) finally: sys.stdout = original A plugin that doesn't want to be auto-instantiated (for example a base class used for several plugins) can set ``autoCreate = False`` as a class attribute. (This attribute is only looked for on the class directly and so isn't inherited by subclasses.) If a plugin is auto-instantiated then the instance will be set as the ``instance`` attribute on the plugin class. ``configSection`` and ``commandLineSwitch`` are described in the `configuration system`_ and `command line integration`_ sections. Plugin instances also have an ``unregister`` method that unhooks all events. It doesn't exactly correspond to the ``register`` method (it undoes some of the work done when a plugin is instantiated) and so can only be called once. Plugins to be loaded are specified in configuration files. For frameworks not using the unittest test runner and configuration system APIs for loading plugins are available in the form of the ``loadPlugins`` function (which uses the configuration system to load plugins) and ``loadPlugin`` which loads an individual plugin by module name. Loading plugins just means importing the module containing the plugin. Configuration system ==================== By default the unittest2 test runner (triggered by the unit2 script or for unittest ``python -m unittest``) loads two configuration files to determine which plugins to load. A user configuration file, ~/unittest.cfg (alternative name and location would be possible), can specify plugins that will always be loaded. A per-project configuration file, unittest.cfg which should be located in the current directory when unit2 is launched, can specify plugins for individual projects. To support this system several command line options have been added to the test runner:: --config=CONFIGLOCATIONS Specify local config file location --no-user-config Don't use user config file --no-plugins Disable all plugins Several config files can be specified using ``--config``. If the user config is being loaded then it will be loaded first (if it exists), followed by the project config (if it exists) *or* any config files specified by ``--config``. ``--config`` can point to specific files, or to a directory containing a ``unittest.cfg``. Config files loaded later are merged into already loaded ones. Where a *key* is in both the later key overrides the earlier one. Where a section is in both but with different keys they are merged. (The exception to keys overriding is the 'plugins' key in the unittest section - these are combined to create a full list of plugins. Perhaps multiline values in config files could also be merged?) plugins to be loaded are specified in the ``plugins`` key of the ``unittest`` section:: [unittest] plugins = unittest2.plugins.checker unittest2.plugins.doctestloader unittest2.plugins.matchregexp unittest2.plugins.moduleloading unittest2.plugins.debugger unittest2.plugins.testcoverage unittest2.plugins.growl unittest2.plugins.filtertests The plugins are simply module names. They either hook themselves up manually on import or are created by virtue of subclassing ``Plugin``. A list of all loaded plugins is available as ``unittest2.events.loadedPlugins`` (a list of strings). For accessing config values there is a ``getConfig(sectionName=None)`` function. By default it returns the whole config data-structure but it an also return individual sections by name. If the section doesn't exist an empty section will be returned. The config data-structure is not read-only but there is no mechanism for persisting changes. The config is a dictionary of ``Section`` objects, where a section is a dictionary subclass with some convenience methods for accessing values:: section = getConfig(sectionName) integer = section.as_int('foo', default=3) number = section.as_float('bar', default=0.0) # as_list returns a list with empty lines and comment lines removed items = section.as_list('items', default=[]) # as_bool allows 'true', '1', 'on', 'yes' for True (matched case-insensitively) and # 'false', 'off', '0', 'no', '' for False value = section.as_bool('value', default=True) If a plugin specifies a ``configSection`` as a class attribute then that section will be fetched and set as the ``config`` attribute on instances. By convention plugins should use the 'always-on' key in their config section to specify that the plugin should be switched on by default. If 'always-on' exists and is set to 'True' then the ``register()`` method will be called on the plugin to hook up all events. If you don't want a plugin to be auto-registered you should fetch the config section yourself rather than using ``configSection``. If the plugin is configured to be 'always-on', and is auto-registered, then it doesn't need a command line switch to turn it on (although it may add other command line switches or options) and ``commandLineSwitch`` will be ignored. Command Line Interface ====================== Plugins may add command line options, either switches with a callback function or options that take values and will be added to a list. There are two functions that do this: ``unittest2.events.addOption`` and ``unittest2.events.addDiscoveryOption``. Some of the events are only applicable to test discovery (``matchPath`` is the only one currently I think), options that use these events should use ``addDiscoveryOption`` which will only be used if test discovery is invoked. Both functions have the same signature:: addDiscoveryOption(callback, opt=None, longOpt=None, help=None) addOption(plugin.method, 'X', '--extreme', 'Run tests in extreme mode') * ``callback`` is a callback function (taking no arguments) to be invoked if the option is on *or* a list indicating that this is an option that takes arguments, values passed in at the command line will be added to the list * ``opt`` is a short option for the command (or None) not including the leading '-' * ``longopt`` a long option for the command (or None) not including the leading '--' * ``help`` is optional help text for the option, to be displayed by ``unit2 -h`` Lowercase short options are reserved for use by unittest2 internally. Plugins may only add uppercase short options. If a plugin needs a simple command line switch (on/off) then it can set the ``commandLineSwitch`` class attribute to a tuple of ``(opt, longOpt, help)``. The ``register()`` method will be used as the callback function, automatically hooking the plugin up to events if it is switched on. The Events ========== This section details the events implemented so far, the order they are called in, what attributes are available on the event objects, whether the event is 'handleable' (and what that means for the event), plus the intended use case for the event. Events in rough order are: * ``pluginsLoaded`` * ``handleFile`` * ``matchPath`` * ``loadTestsFromNames`` * ``loadTestsFromName`` * ``loadTestsFromModule`` * ``loadTestsFromTestCase`` * ``getTestCaseNames`` * ``runnerCreated`` * ``startTestRun`` * ``startTest`` * ``onTestFail`` * ``stopTest`` * ``stopTestRun`` pluginsLoaded ------------- This event is useful for plugin initialisation. It is fired after all plugins have been loaded, the config file has been read and command line options processed. The ``PluginsLoadedEvent`` has one attribute: ``loadedPlugins`` which is a list of strings referring to all plugin modules that have been loaded. handleFile ---------- This event is fired when a file is looked at in test discovery or a *filename* is passed at the command line. It can be used for loading tests from non-Python files, like doctests from text files, or adding tests for a file like pep8 and pyflakes checks. A ``HandleFileEvent`` object has the following attributes: * ``extraTests`` - a list, extend this with tests to *add* tests that will be loaded from this file without preventing the default test loading * ``name`` - the name of the file * ``path`` - the full path of the file being looked at * ``loader`` - the ``TestLoader`` in use * ``pattern`` - the pattern being used to match files, or None if not called during test discovery * ``top_level_directory`` - the top level directory of the project tests are being loaded from, or the current working directory if not called during test discovery This event *can* be handled. If it is handled then the handler should return a test suite or None. Returning None means no tests will be loaded from this file. If any plugin has created any ``extraTests`` then these will be used even if a handler handles the event and returns None. If this event is not handled then it will be matched against the pattern (test discovery only) and either be rejected or go through for standard test loading. matchPath --------- ``matchPath`` is called to determine if a file should be loaded as a test module. This event only fires during test discovery. ``matchPath`` is only fired if the filename can be converted to a valid python module name, this is because tests are loaded by importing. If you want to load tests from files whose paths don't translate to valid python identifiers then you should use ``handleFile`` instead. A ``MatchPathEvent`` has the following attributes: * ``path`` - full path to the file * ``name`` - filename only * ``pattern`` - pattern being used for discovery This event *can* be handled. If it is handled then the handler should return True or False to indicate whether or not test loading should be attempted from this file. If this event is not handled then the pattern supplied to test discovery will be used as a glob pattern to match the filename. loadTestsFromNames ------------------ This event is fired when ``TestLoader.loadTestsFromNames`` is called. Attributes on the ``LoadFromNamesEvent`` object are: * ``loader`` - the test loader * ``names`` - a list of the names being loaded * ``module`` - the module passed to ``loader.loadTestsFromNames(...)`` * ``extraTests`` - a list of extra tests to be added to the suites loaded from the names This event can be handled. If it is handled then the handler should return a list of suites or None. Returning None means no tests will be loaded from these names. If any plugin has created any ``extraTests`` then these will be used even if a handler handles the event and returns None. If this event is not handled then ``loader.loadTestFromName`` will be called for each name to build up the list of suites. loadTestsFromName ----------------- This event is fired when ``TestLoader.loadTestsFromName`` is called. Attributes on the ``LoadFromNameEvent`` object are: * ``loader`` - the test loader * ``name`` - the name being loaded * ``module`` - the module passed to ``loader.loadTestsFromName(...)`` * ``extraTests`` - a suite of extra tests to be added to the suite loaded from the name This event can be handled. If it is handled then the handler should return a TestSuite or None. Returning None means no tests will be loaded from this name. If any plugin has created any ``extraTests`` then these will be used even if a handler handles the event and returns None. If the event is not handled then each name will be resolved and tests loaded from it, which may mean calling ``loader.loadTestsFromModule`` or ``loader.loadTestsFromTestCase``. loadTestsFromModule ------------------- This event is fired when ``TestLoader.loadTestsFromModule`` is called. It can be used to customise the loading of tests from a module, for example loading tests from functions as well as from TestCase classes. Attributes on the ``LoadFromModuleEvent`` object are: * ``loader`` - the test loader * ``module`` - the module object tests * ``extraTests`` - a suite of extra tests to be added to the suite loaded from the module This event can be handled. If it is handled then the handler should return a TestSuite or None. Returning None means no tests will be loaded from this module. If any plugin has created any ``extraTests`` then these will be used even if a handler handles the event and returns None. If the event is not handled then ``loader.loadTestsFromTestCase`` will be called for every TestCase in the module. Event if the event is handled, if the module defines a ``load_tests`` function then it *will* be called for the module. This removes the responsibility for implementing the ``load_tests`` protocol from plugin authors. loadTestsFromTestCase --------------------- This event is fired when ``TestLoader.loadTestsFromTestCase`` is called. It could be used to customise the loading of tests from a TestCase, for example loading tests with an alternative prefix or created generative / parameterized tests. Attributes on the ``LoadFromTestCaseEvent`` object are: * ``loader`` - the test loader * ``testCase`` - the test case class being loaded * ``extraTests`` - a suite of extra tests to be added to the suite loaded from the TestCase This event can be handled. If it is handled then the handler should return a TestSuite or None. Returning None means no tests will be loaded from this module. If any plugin has created any ``extraTests`` then these will be used even if a handler handles the event and returns None If the event is not handled then ``loader.getTestCaseNames`` will be called to get method names from the test case and a suite will be created by instantiating the TestCase class with each name it returns. getTestCaseNames ---------------- This event is fired when ``TestLoader.getTestCaseNames`` is called. It could be used to customise the method names used to load tests from a TestCase, for example loading tests with an alternative prefix from the default or filtering for specific names. Attributes on the ``GetTestCaseNamesEvent`` object are: * ``loader`` - the test loader * ``testCase`` - the test case class that tests are being loaded from * ``testMethodPrefix`` - set to None, modify this attribute to *change* the prefix being used for this class * ``extraNames`` - a list of extra names to use for this test case as well as the default ones * ``excludedNames`` - a list of names to exclude from loading from this class This event can be handled. If it is handled it should return a list of strings. Note that if this event returns an empty list (or None which will be replaced with an empty list then ``loadTestsFromTestCase`` will still check to see if the TestCase has a ``runTest`` method. Even if the event is handled ``extraNames`` will still be added to the list, however *excludedNames`` won't be removed as they are filtered out by the default implementation which looks for all attributes that are methods (or callable) whose name begins with ``loader.testMethodPrefix`` (or ``event.testMethodPrefix`` if that is set) and aren't in the list of excluded names (converted to a set first for efficient lookup). The list of names will also be sorted using ``loader.sortTestMethodsUsing``. runnerCreated ------------- This event is fired when the ``TextTestRunner`` is instantiated. It can be used to customize the test runner, for example replace the stream and result class, without needing to write a custom test harness. This should allow the default test runner script (``unit2`` or ``python -m untitest``) to be suitable for a greater range of projects. Projects that want to use custom test reporting should be able to do it through a plugin rather than having to rebuild the runner and result machinery, which also requires writing custom test collection too. The ``RunnerCreatedEvent`` object only has one attribute; ``runner`` which is the runner instance. startTestRun ------------ This event is fired when the test run is started. This is used, for example, by the growl notifier that displays a growl notification when a test run begins. It can also be used for filtering tests after they have all been loaded or for taking over the test run machinery altogether, for distributed testing for example. The ``StartTestRunEvent`` object has the following attributes: * ``test`` - the full suite of all tests to be run (may be modified in place) * ``result`` - the result object * ``startTime`` - the time the test run started Currently this event can be handled. This prevents the normal test run from executing, allowing an alternative implementation, but the return value is unused. Handling this event (as with handling any event) prevents other plugins from executing. This means that the it wouldn't be possible to safely combine a distributed test runner with a plugin that filters the suite. Fixing this issue is one of the open issues with the plugin system. startTest --------- This event is fired immediately before a test is executed (inside ``TestCase.run(...)``). The ``StartTestEvent`` object has the following attributes: * ``test`` - the test to be run * ``result`` - the result object * ``startTime`` - the time the test starts execution This event cannot be handled. onTestFail ---------- This event is fired when a test setUp, a test, a tearDown or a cleanUp fails or errors. It is currently used by the debugger plugin. It is *not* currently called for 'internal' unittest exceptions like ``SkipTest`` or expected failures and unexpected successes. Attributes on the ``TestFailEvent`` are: * ``test`` - the test * ``result`` - the result * ``exc_info`` - the result of ``sys.exc_info()`` after the error / fail * ``when`` - one of 'setUp', 'call', 'tearDown', or 'cleanUp' This event cannot be handled. Should this event be able to suppress raised exceptions? It should also be able to modify the traceback so that bare asserts could be used but still provide useful diagnostic information. Should this event be fired for test skips? stopTest -------- This event is fired when a test execution is completed. It includes a great deal of information about the test and could be used to completely replace test reporting, making the test result potentially obsolete. It will be used by the junit-xml plugin to generate the xml reports describing the test run. If there are errors during a tearDown or clean up functions then this event may be fired several times for a test. For each call the ``stage`` will be different, although there could be several errors during clean up functions. Attributes on the ``StopTestEvent`` are: * ``test`` - the test * ``result`` - the result * ``exc_info`` - the result of ``sys.exc_info()`` after an error / fail or None for success * ``stopTime``- time the test stopped, including tear down and clean up functions * ``timeTaken`` - total time for test execution from setUp to clean up functions * ``stage`` - one of setUp, call, tearDown, cleanUp, or None for success * ``outcome`` - one of passed, failed, error, skipped, unexpectedSuccess, expectedFailure The outcomes all correspond to an attribute that will be set to True or False depending on outcome: * ``passed`` * ``failed`` * ``error`` * ``skipped`` * ``unexpectedSuccess`` * ``expectedFailure`` In addition there is a ``skipReason`` that will be None unless the test was skipped, in which case it will be a string containing the reason. This event cannot be handled. stopTestRun ----------- This event is fired when the test run completes. It is useful for reporting tools. The ``StopTestRunEvent`` event objects have the following attributes: * ``runner`` - the test runner * ``result`` - the test result * ``stopTime`` - the time the test run completes * ``timeTaken`` - total time taken by the test run

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Re: [Python-Dev] PEP 382 progress: import hooks
by P.J. Eby 03 Aug '10

03 Aug '10

At 11:57 AM 7/23/2010 +0100, Brett Cannon wrote: >On Thu, Jul 22, 2010 at 19:19, P.J. Eby ><<mailto:pje@telecommunity.com>pje(a)telecommunity.com> wrote: > >What does "is not a package" actually mean in that context? > > >The module is a module but not a package. Um... that's not any clearer. Are you saying that a module of the same name takes precedence over a package? Is that the current precedence as well? >Regarding load_module_with_path(), how does its specification differ >from simply creating a module in sys.modules, setting its __path__, >and then invoking the standard load_module()? Â (i.e., is this >method actually needed, since a correct PEP 302 loader *must* reuse >an existing module object in sys.modules) > > >It must reuse the module itself but a proper reload would reset >__path__ as leaving it unchanged is not a proper resetting of the >module object. So this module is needed in order to force the loaderÂ Um, no. Reloading doesn't reset the module contents, not even __path__. Never has, from Python 2.2 through 2.7 -- even in 3.1. At least, not for normal filesystem .py/.pyc files. (I tested with 'os', adding an extra 'foo' attribute, and also setting a __path__; both were unaffected by reload(), in all 7 Python versions. Perhaps you're saying this happens with zipfiles, or packages that already have a __path__, or...? >Â > >Am I correct in understanding that, as written, one would have to >redefine __import__ to implement this in a library for older Python >versions? Â Or is it implementable as a meta_path importer? > > >Redefine __import__ (unless Martin and I are missing something, but >I tried to think of how to implement this use sys.meta_path and >couldn't come up with a solution). I'm thinking it *could* be done with a meta_path hook, but only by doubling the search length in the event that the search failed. That seems a bit icky, but replacing the entire import process seems ickier (more code surface to maintain, more bug potential) in the case of supporting older Pythons.

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