introduce an experimental approach for allowing dynamic addition of hooks from plugin. Plugins may register new hooks by implementing the new

pytest_registerhooks(pluginmanager)

and call

    pluginmanager.registerhooks(module)

with the referenced 'module' object containing the hooks.

The new pytest_registerhooks is called after pytest_addoption
and before pytest_configure.

--HG--
branch : trunk

CHANGELOG

@@ -1,6 +1,7 @@
-Changes between 1.2.1 and XXX
+Changes between 1.2.1 and 1.2.2 (release pending)
-=====================================
+==================================================
 
+- new mechanism to allow plugins to register new hooks 
 - added links to the new capturelog and coverage plugins 
 - (issue87) fix unboundlocal error in assertionold code 
 - (issue86) improve documentation for looponfailing

py/__init__.py

@@ -8,9 +8,8 @@ dictionary or an import path.
 
 (c) Holger Krekel and others, 2004-2010
 """
-version = "1.2.1"
+_version__ = version = "1.2.2"
 
-__version__ = version = version or "1.2.x"
 import py.apipkg
 
 py.apipkg.initpkg(__name__, dict(

py/_plugin/hookspec.py

@@ -9,6 +9,9 @@ hook specifications for py.test plugins
 def pytest_addoption(parser):
     """ called before commandline parsing.  """
 
+def pytest_registerhooks(pluginmanager):
+    """ called after commandline parsing before pytest_configure.  """
+
 def pytest_namespace():
     """ return dict of name->object which will get stored at py.test. namespace"""
 
@@ -133,31 +136,6 @@ def pytest_doctest_prepare_content(content):
     """ return processed content for a given doctest"""
 pytest_doctest_prepare_content.firstresult = True
 
-# -------------------------------------------------------------------------
-# distributed testing 
-# -------------------------------------------------------------------------
-
-def pytest_gwmanage_newgateway(gateway, platinfo):
-    """ called on new raw gateway creation. """ 
-
-def pytest_gwmanage_rsyncstart(source, gateways):
-    """ called before rsyncing a directory to remote gateways takes place. """
-
-def pytest_gwmanage_rsyncfinish(source, gateways):
-    """ called after rsyncing a directory to remote gateways takes place. """
-
-def pytest_testnodeready(node):
-    """ Test Node is ready to operate. """
-
-def pytest_testnodedown(node, error):
-    """ Test Node is down. """
-
-def pytest_rescheduleitems(items):
-    """ reschedule Items from a node that went down. """
-
-def pytest_looponfailinfo(failreports, rootdirs):
-    """ info for repeating failing tests. """
-
 
 # -------------------------------------------------------------------------
 # error handling and internal debugging hooks 

py/_plugin/pytest__pytest.py

@@ -34,15 +34,18 @@ class HookRecorder:
         self._recorders = {}
         
     def start_recording(self, hookspecs):
-        assert hookspecs not in self._recorders 
+        if not isinstance(hookspecs, (list, tuple)):
-        class RecordCalls: 
+            hookspecs = [hookspecs]
-            _recorder = self 
+        for hookspec in hookspecs:
-        for name, method in vars(hookspecs).items():
+            assert hookspec not in self._recorders 
-            if name[0] != "_":
+            class RecordCalls: 
-                setattr(RecordCalls, name, self._makecallparser(method))
+                _recorder = self 
-        recorder = RecordCalls()
+            for name, method in vars(hookspec).items():
-        self._recorders[hookspecs] = recorder
+                if name[0] != "_":
-        self._registry.register(recorder)
+                    setattr(RecordCalls, name, self._makecallparser(method))
+            recorder = RecordCalls()
+            self._recorders[hookspec] = recorder
+            self._registry.register(recorder)
         self.hook = HookRelay(hookspecs, registry=self._registry)
 
     def finish_recording(self):

py/_plugin/pytest_helpconfig.py

@@ -93,9 +93,11 @@ def pytest_report_header(config):
 # =====================================================
 
 def pytest_plugin_registered(manager, plugin):
-    hookspec = manager.hook._hookspecs
     methods = collectattr(plugin)
-    hooks = collectattr(hookspec)
+    hooks = {}
+    for hookspec in manager.hook._hookspecs:
+        hooks.update(collectattr(hookspec))
+    
     stringio = py.io.TextIO()
     def Print(*args):
         if args:
@@ -109,10 +111,13 @@ def pytest_plugin_registered(manager, plugin):
         if isgenerichook(name):
             continue
         if name not in hooks: 
-            Print("found unknown hook:", name)
+            if not getattr(method, 'optionalhook', False):
-            fail = True
+                Print("found unknown hook:", name)
+                fail = True
         else:
+            #print "checking", method
             method_args = getargs(method)
+            #print "method_args", method_args
             if '__multicall__' in method_args:
                 method_args.remove('__multicall__')
             hook = hooks[name]

py/_plugin/pytest_terminal.py

@@ -6,6 +6,8 @@ This is a good source for looking at the various reporting hooks.
 import py
 import sys
 
+optionalhook = py.test.mark.optionalhook
+
 def pytest_addoption(parser):
     group = parser.getgroup("terminal reporting", "reporting", after="general")
     group._addoption('-v', '--verbose', action="count", 
@@ -130,6 +132,15 @@ class TerminalReporter:
         for line in str(excrepr).split("\n"):
             self.write_line("INTERNALERROR> " + line)
 
+    def pytest_plugin_registered(self, plugin):
+        if self.config.option.traceconfig: 
+            msg = "PLUGIN registered: %s" %(plugin,)
+            # XXX this event may happen during setup/teardown time 
+            #     which unfortunately captures our output here 
+            #     which garbles our output if we use self.write_line 
+            self.write_line(msg)
+
+    @optionalhook
     def pytest_gwmanage_newgateway(self, gateway, platinfo):
         #self.write_line("%s instantiated gateway from spec %r" %(gateway.id, gateway.spec._spec))
         d = {}
@@ -149,30 +160,37 @@ class TerminalReporter:
         self.write_line(infoline)
         self.gateway2info[gateway] = infoline
 
-    def pytest_plugin_registered(self, plugin):
+    @optionalhook
-        if self.config.option.traceconfig: 
-            msg = "PLUGIN registered: %s" %(plugin,)
-            # XXX this event may happen during setup/teardown time 
-            #     which unfortunately captures our output here 
-            #     which garbles our output if we use self.write_line 
-            self.write_line(msg)
-
     def pytest_testnodeready(self, node):
         self.write_line("[%s] txnode ready to receive tests" %(node.gateway.id,))
 
+    @optionalhook
     def pytest_testnodedown(self, node, error):
         if error:
             self.write_line("[%s] node down, error: %s" %(node.gateway.id, error))
 
+    @optionalhook
+    def pytest_rescheduleitems(self, items):
+        if self.config.option.debug:
+            self.write_sep("!", "RESCHEDULING %s " %(items,))
+
+    @optionalhook
+    def pytest_looponfailinfo(self, failreports, rootdirs):
+        if failreports:
+            self.write_sep("#", "LOOPONFAILING", red=True)
+            for report in failreports:
+                loc = self._getcrashline(report)
+                self.write_line(loc, red=True)
+        self.write_sep("#", "waiting for changes")
+        for rootdir in rootdirs:
+            self.write_line("### Watching:   %s" %(rootdir,), bold=True)
+
+
     def pytest_trace(self, category, msg):
         if self.config.option.debug or \
            self.config.option.traceconfig and category.find("config") != -1:
             self.write_line("[%s] %s" %(category, msg))
 
-    def pytest_rescheduleitems(self, items):
-        if self.config.option.debug:
-            self.write_sep("!", "RESCHEDULING %s " %(items,))
-
     def pytest_deselected(self, items):
         self.stats.setdefault('deselected', []).append(items)
 
@@ -274,16 +292,6 @@ class TerminalReporter:
         else:
             excrepr.reprcrash.toterminal(self._tw)
 
-    def pytest_looponfailinfo(self, failreports, rootdirs):
-        if failreports:
-            self.write_sep("#", "LOOPONFAILING", red=True)
-            for report in failreports:
-                loc = self._getcrashline(report)
-                self.write_line(loc, red=True)
-        self.write_sep("#", "waiting for changes")
-        for rootdir in rootdirs:
-            self.write_line("### Watching:   %s" %(rootdir,), bold=True)
-
     def _getcrashline(self, report):
         try:
             return report.longrepr.reprcrash

py/_test/pluginmanager.py

@@ -7,7 +7,7 @@ from py._plugin import hookspec
 from py._test.outcome import Skipped
 
 default_plugins = (
-    "default runner capture terminal mark skipping tmpdir monkeypatch "
+    "default runner capture mark terminal skipping tmpdir monkeypatch "
     "recwarn pdb pastebin unittest helpconfig nose assertion genscript "
     "junitxml doctest").split()
 
@@ -20,7 +20,7 @@ class PluginManager(object):
         self.registry = Registry()
         self._name2plugin = {}
         self._hints = []
-        self.hook = HookRelay(hookspecs=hookspec, registry=self.registry) 
+        self.hook = HookRelay([hookspec], registry=self.registry) 
         self.register(self)
         for spec in default_plugins:
             self.import_plugin(spec)
@@ -40,6 +40,8 @@ class PluginManager(object):
         if name in self._name2plugin:
             return False
         self._name2plugin[name] = plugin
+        self.call_plugin(plugin, "pytest_registerhooks", 
+            {'pluginmanager': self})
         self.hook.pytest_plugin_registered(manager=self, plugin=plugin)
         self.registry.register(plugin)
         return True
@@ -58,6 +60,9 @@ class PluginManager(object):
             if plugin == val:
                 return True
 
+    def registerhooks(self, spec):
+        self.hook._registerhooks(spec)
+
     def getplugins(self):
         return list(self.registry)
 
@@ -301,13 +306,21 @@ class Registry:
 
 class HookRelay: 
     def __init__(self, hookspecs, registry):
-        self._hookspecs = hookspecs
+        if not isinstance(hookspecs, list):
+            hookspecs = [hookspecs]
+        self._hookspecs = []
         self._registry = registry
+        for hookspec in hookspecs:
+            self._registerhooks(hookspec)
+
+    def _registerhooks(self, hookspecs):
+        self._hookspecs.append(hookspecs)
         for name, method in vars(hookspecs).items():
             if name[:1] != "_":
                 firstresult = getattr(method, 'firstresult', False)
                 hc = HookCaller(self, name, firstresult=firstresult)
                 setattr(self, name, hc)
+                #print ("setting new hook", name)
 
     def _performcall(self, name, multicall):
         return multicall.execute()

setup.py

@@ -27,7 +27,7 @@ def main():
         name='py',
         description='py.test and pylib: rapid testing and development utils.',
         long_description = long_description,
-        version= trunk or '1.2.1',
+        version= trunk or '1.2.2',
         url='http://pylib.org',
         license='MIT license',
         platforms=['unix', 'linux', 'osx', 'cygwin', 'win32'],

testing/plugin/test_pytest__pytest.py

@@ -34,7 +34,7 @@ def test_functional(testdir, linecomp):
         def test_func(_pytest):
             class ApiClass:
                 def xyz(self, arg):  pass 
-            hook = HookRelay(ApiClass, Registry())
+            hook = HookRelay([ApiClass], Registry())
             rec = _pytest.gethookrecorder(hook)
             class Plugin:
                 def xyz(self, arg):

testing/plugin/test_pytest_helpconfig.py

@@ -29,3 +29,24 @@ def test_collectattr():
     methods = py.builtin.sorted(collectattr(B()))
     assert list(methods) == ['pytest_hello', 'pytest_world']
 
+def test_hookvalidation_unknown(testdir):
+    testdir.makeconftest("""
+        def pytest_hello(xyz):
+            pass
+    """)
+    result = testdir.runpytest()
+    assert result.ret != 0
+    assert result.stderr.fnmatch_lines([
+        '*unknown hook*pytest_hello*'
+    ])
+
+def test_hookvalidation_optional(testdir):
+    testdir.makeconftest("""
+        import py
+        @py.test.mark.optionalhook 
+        def pytest_hello(xyz):
+            pass
+    """)
+    result = testdir.runpytest()
+    assert result.ret == 0
+