fix issue89 - allow py.test.mark decorators to be used with classes

(if you are using >=python2.6)
also allow to have multiple markers applied at class level
and test and fix a bug with chained skip/xfail decorators:
if any of the conditions is true a test will be skipped/xfailed
with a explanation which condition evaluated to true.

--HG--
branch : trunk

testing/plugin/test_pytest_mark.py

@@ -68,11 +68,41 @@ class TestFunctional:
         keywords = item.readkeywords()
         assert 'hello' in keywords
 
-    def test_mark_per_class(self, testdir):
+    def test_marklist_per_class(self, testdir):
         modcol = testdir.getmodulecol("""
             import py
             class TestClass:
-                pytestmark = py.test.mark.hello
+                pytestmark = [py.test.mark.hello, py.test.mark.world]
+                def test_func(self):
+                    assert TestClass.test_func.hello  
+                    assert TestClass.test_func.world
+        """)
+        clscol = modcol.collect()[0]
+        item = clscol.collect()[0].collect()[0]
+        keywords = item.readkeywords()
+        assert 'hello' in keywords
+
+    def test_marklist_per_module(self, testdir):
+        modcol = testdir.getmodulecol("""
+            import py
+            pytestmark = [py.test.mark.hello, py.test.mark.world]
+            class TestClass:
+                def test_func(self):
+                    assert TestClass.test_func.hello  
+                    assert TestClass.test_func.world
+        """)
+        clscol = modcol.collect()[0]
+        item = clscol.collect()[0].collect()[0]
+        keywords = item.readkeywords()
+        assert 'hello' in keywords
+        assert 'world' in keywords
+
+    @py.test.mark.skipif("sys.version_info < (2,6)")
+    def test_mark_per_class_decorator(self, testdir):
+        modcol = testdir.getmodulecol("""
+            import py
+            @py.test.mark.hello
+            class TestClass:
                 def test_func(self):
                     assert TestClass.test_func.hello  
         """)
@@ -81,6 +111,23 @@ class TestFunctional:
         keywords = item.readkeywords()
         assert 'hello' in keywords
 
+    @py.test.mark.skipif("sys.version_info < (2,6)")
+    def test_mark_per_class_decorator_plus_existing_dec(self, testdir):
+        modcol = testdir.getmodulecol("""
+            import py
+            @py.test.mark.hello
+            class TestClass:
+                pytestmark = py.test.mark.world
+                def test_func(self):
+                    assert TestClass.test_func.hello  
+                    assert TestClass.test_func.world
+        """)
+        clscol = modcol.collect()[0]
+        item = clscol.collect()[0].collect()[0]
+        keywords = item.readkeywords()
+        assert 'hello' in keywords
+        assert 'world' in keywords
+
     def test_merging_markers(self, testdir):
         p = testdir.makepyfile("""
             import py

testing/plugin/test_pytest_skipping.py

@@ -52,6 +52,39 @@ class TestEvaluator:
         assert expl == "hello world"
         assert ev.get("attr") == 2
 
+    def test_marked_one_arg_twice(self, testdir):
+        lines = [
+            '''@py.test.mark.skipif("not hasattr(os, 'murks')")''',
+            '''@py.test.mark.skipif("hasattr(os, 'murks')")'''
+        ]
+        for i in range(0, 2):
+            item = testdir.getitem("""
+                import py 
+                %s
+                %s
+                def test_func(): 
+                    pass
+            """ % (lines[i], lines[(i+1) %2]))
+            ev = MarkEvaluator(item, 'skipif')
+            assert ev
+            assert ev.istrue()
+            expl = ev.getexplanation()
+            assert expl == "condition: not hasattr(os, 'murks')"
+
+    def test_marked_one_arg_twice2(self, testdir):
+        item = testdir.getitem("""
+            import py 
+            @py.test.mark.skipif("hasattr(os, 'murks')")
+            @py.test.mark.skipif("not hasattr(os, 'murks')")
+            def test_func(): 
+                pass
+        """)
+        ev = MarkEvaluator(item, 'skipif')
+        assert ev
+        assert ev.istrue()
+        expl = ev.getexplanation()
+        assert expl == "condition: not hasattr(os, 'murks')"
+
     def test_skipif_class(self, testdir):
         item, = testdir.getitems("""
             import py