Inline FunctionMixin with Function

src/_pytest/python.py

@@ -21,6 +21,7 @@
 from _pytest import fixtures
 from _pytest import nodes
 from _pytest._code import filter_traceback
+from _pytest._code.code import ExceptionInfo
 from _pytest.compat import ascii_escaped
 from _pytest.compat import get_default_arg_names
 from _pytest.compat import get_real_func
@@ -503,9 +504,7 @@ def _importtestmodule(self):
         try:
             mod = self.fspath.pyimport(ensuresyspath=importmode)
         except SyntaxError:
-            raise self.CollectError(
-                _pytest._code.ExceptionInfo.from_current().getrepr(style="short")
-            )
+            raise self.CollectError(ExceptionInfo.from_current().getrepr(style="short"))
         except self.fspath.ImportMismatchError:
             e = sys.exc_info()[1]
             raise self.CollectError(
@@ -518,8 +517,6 @@ def _importtestmodule(self):
                 "unique basename for your test file modules" % e.args
             )
         except ImportError:
-            from _pytest._code.code import ExceptionInfo
-
             exc_info = ExceptionInfo.from_current()
             if self.config.getoption("verbose") < 2:
                 exc_info.traceback = exc_info.traceback.filter(filter_traceback)
@@ -773,45 +770,6 @@ def newinstance(self):
         return self.obj
 
 
-class FunctionMixin(PyobjMixin):
-    """ mixin for the code common to Function and Generator.
-    """
-
-    def setup(self):
-        """ perform setup for this test function. """
-        if isinstance(self.parent, Instance):
-            self.parent.newinstance()
-            self.obj = self._getobj()
-
-    def _prunetraceback(self, excinfo):
-        if hasattr(self, "_obj") and not self.config.getoption("fulltrace", False):
-            code = _pytest._code.Code(get_real_func(self.obj))
-            path, firstlineno = code.path, code.firstlineno
-            traceback = excinfo.traceback
-            ntraceback = traceback.cut(path=path, firstlineno=firstlineno)
-            if ntraceback == traceback:
-                ntraceback = ntraceback.cut(path=path)
-                if ntraceback == traceback:
-                    ntraceback = ntraceback.filter(filter_traceback)
-                    if not ntraceback:
-                        ntraceback = traceback
-
-            excinfo.traceback = ntraceback.filter()
-            # issue364: mark all but first and last frames to
-            # only show a single-line message for each frame
-            if self.config.getoption("tbstyle", "auto") == "auto":
-                if len(excinfo.traceback) > 2:
-                    for entry in excinfo.traceback[1:-1]:
-                        entry.set_repr_style("short")
-
-    def repr_failure(self, excinfo, outerr=None):
-        assert outerr is None, "XXX outerr usage is deprecated"
-        style = self.config.getoption("tbstyle", "auto")
-        if style == "auto":
-            style = "long"
-        return self._repr_failure_py(excinfo, style=style)
-
-
 def hasinit(obj):
     init = getattr(obj, "__init__", None)
     if init:
@@ -1397,7 +1355,7 @@ def write_docstring(tw, doc, indent="    "):
             tw.write(indent + line + "\n")
 
 
-class Function(FunctionMixin, nodes.Item):
+class Function(PyobjMixin, nodes.Item):
     """ a Function Item is responsible for setting up and executing a
     Python test function.
     """
@@ -1501,10 +1459,40 @@ def runtest(self):
         """ execute the underlying test function. """
         self.ihook.pytest_pyfunc_call(pyfuncitem=self)
 
-    def setup(self):
-        super().setup()
+    def setup(self) -> None:
+        if isinstance(self.parent, Instance):
+            self.parent.newinstance()
+            self.obj = self._getobj()
         fixtures.fillfixtures(self)
 
+    def _prunetraceback(self, excinfo: ExceptionInfo) -> None:
+        if hasattr(self, "_obj") and not self.config.getoption("fulltrace", False):
+            code = _pytest._code.Code(get_real_func(self.obj))
+            path, firstlineno = code.path, code.firstlineno
+            traceback = excinfo.traceback
+            ntraceback = traceback.cut(path=path, firstlineno=firstlineno)
+            if ntraceback == traceback:
+                ntraceback = ntraceback.cut(path=path)
+                if ntraceback == traceback:
+                    ntraceback = ntraceback.filter(filter_traceback)
+                    if not ntraceback:
+                        ntraceback = traceback
+
+            excinfo.traceback = ntraceback.filter()
+            # issue364: mark all but first and last frames to
+            # only show a single-line message for each frame
+            if self.config.getoption("tbstyle", "auto") == "auto":
+                if len(excinfo.traceback) > 2:
+                    for entry in excinfo.traceback[1:-1]:
+                        entry.set_repr_style("short")
+
+    def repr_failure(self, excinfo, outerr=None):
+        assert outerr is None, "XXX outerr usage is deprecated"
+        style = self.config.getoption("tbstyle", "auto")
+        if style == "auto":
+            style = "long"
+        return self._repr_failure_py(excinfo, style=style)
+
 
 class FunctionDefinition(Function):
     """