[WIP] classmethod and class-scoped fixtures (#3778)

src/_pytest/pytester.py

@@ -667,7 +667,9 @@ def copy_example(self, name=None):
             example_path.copy(result)
             return result
         else:
-            raise LookupError("example is not found as a file or directory")
+            raise LookupError(
+                "example {} is not found as a file or directory".format(example_path)
+            )
 
     Session = Session
 

testing/example_scripts/fixtures/fill_fixtures/class_variable_auto_use.py

@@ -0,0 +1,11 @@
+import pytest
+
+
+class Test(object):
+    @classmethod
+    @pytest.fixture(scope="class", autouse=True)
+    def setup(cls):
+        cls.url = "localhost:5000"
+
+    def test_url(self):
+        assert self.url == "localhost:5000"

testing/python/fixture.py

@@ -371,6 +371,11 @@ def test_foo(request):
         result = testdir.runpytest()
         assert result.ret == 0
 
+    def test_class_variable_auto_use(self, testdir):
+        p = testdir.copy_example("class_variable_auto_use.py")
+        result = testdir.runpytest(p)
+        result.stdout.fnmatch_lines("* 1 passed *")
+
     def test_funcarg_lookup_error(self, testdir):
         testdir.makeconftest(
             """