fix and improve error reporting for parametrizing funcargs (originally reported by antlong)

_pytest/python.py

@@ -486,10 +486,11 @@ def hasinit(obj):
             return True
 
 
-def getfuncargnames(function):
+def getfuncargnames(function, startindex=None):
     # XXX merge with main.py's varnames
     argnames = py.std.inspect.getargs(py.code.getrawcode(function))[0]
-    startindex = py.std.inspect.ismethod(function) and 1 or 0
+    if startindex is None:
+        startindex = py.std.inspect.ismethod(function) and 1 or 0
     defaults = getattr(function, 'func_defaults',
                        getattr(function, '__defaults__', None)) or ()
     numdefaults = len(defaults)
@@ -518,7 +519,8 @@ class Metafunc:
         self.config = config
         self.module = module
         self.function = function
-        self.funcargnames = getfuncargnames(function)
+        self.funcargnames = getfuncargnames(function,
+                                            startindex=int(cls is not None))
         self.cls = cls
         self.module = module
         self._calls = []
@@ -526,7 +528,11 @@ class Metafunc:
 
     def addcall(self, funcargs=None, id=_notexists, param=_notexists):
         """ add a new call to the underlying test function during the
-        collection phase of a test run.
+        collection phase of a test run.  Note that request.addcall() is
+        called during the test collection phase prior and independently
+        to actual test execution.  Therefore you should perform setup
+        of resources in a funcarg factory which can be instrumented
+        with the ``param``.
 
         :arg funcargs: argument keyword dictionary used when invoking
             the test function.
@@ -538,10 +544,13 @@ class Metafunc:
         :arg param: will be exposed to a later funcarg factory invocation
             through the ``request.param`` attribute.  It allows to
             defer test fixture setup activities to when an actual
-            test is run.  Note that request.addcall() is called during
+            test is run.
-            the collection phase of a test run.
         """
         assert funcargs is None or isinstance(funcargs, dict)
+        if funcargs is not None:
+            for name in funcargs:
+                if name not in self.funcargnames:
+                    pytest.fail("funcarg %r not used in this function." % name)
         if id is None:
             raise ValueError("id=None not allowed")
         if id is _notexists:

pytest.py

@@ -1,7 +1,7 @@
 """
 unit and functional testing with Python.
 """
-__version__ = '2.0.2.dev2'
+__version__ = '2.0.2.dev3'
 __all__ = ['main']
 
 from _pytest.core import main, UsageError, _preloadplugins

setup.py

@@ -22,7 +22,7 @@ def main():
         name='pytest',
         description='py.test: simple powerful testing with Python',
         long_description = long_description,
-        version='2.0.2.dev2',
+        version='2.0.2.dev3',
         url='http://pytest.org',
         license='MIT license',
         platforms=['unix', 'linux', 'osx', 'cygwin', 'win32'],

testing/test_python.py

@@ -915,11 +915,12 @@ class TestMetafunc:
         assert metafunc._calls[2].param == 1
 
     def test_addcall_funcargs(self):
-        def func(arg1): pass
+        def func(x): pass
         metafunc = funcargs.Metafunc(func)
         class obj: pass
         metafunc.addcall(funcargs={"x": 2})
         metafunc.addcall(funcargs={"x": 3})
+        pytest.raises(pytest.fail.Exception, "metafunc.addcall({'xyz': 0})")
         assert len(metafunc._calls) == 2
         assert metafunc._calls[0].funcargs == {'x': 2}
         assert metafunc._calls[1].funcargs == {'x': 3}
@@ -1003,6 +1004,21 @@ class TestGenfuncFunctional:
             "*1 failed, 3 passed*"
         ])
 
+    def test_noself_in_method(self, testdir):
+        p = testdir.makepyfile("""
+            def pytest_generate_tests(metafunc):
+                assert 'xyz' not in metafunc.funcargnames
+
+            class TestHello:
+                def test_hello(xyz):
+                    pass
+        """)
+        result = testdir.runpytest(p)
+        result.stdout.fnmatch_lines([
+            "*1 pass*",
+        ])
+
+
     def test_generate_plugin_and_module(self, testdir):
         testdir.makeconftest("""
             def pytest_generate_tests(metafunc):
@@ -1339,5 +1355,3 @@ def test_customize_through_attributes(testdir):
         "*MyInstance*",
         "*MyFunction*test_hello*",
     ])
-
-