py.builtins._totext -> string literals or six.text_type

src/_pytest/outcomes.py

@@ -3,7 +3,6 @@ exception classes and constants handling test outcomes
 as well as functions creating them
 """
 from __future__ import absolute_import, division, print_function
-import py
 import sys
 
 
@@ -21,7 +20,7 @@ class OutcomeException(BaseException):
         if self.msg:
             val = self.msg
             if isinstance(val, bytes):
-                val = py._builtin._totext(val, errors="replace")
+                val = val.decode("UTF-8", errors="replace")
             return val
         return "<%s instance>" % (self.__class__.__name__,)
 

src/_pytest/python.py

@@ -741,7 +741,7 @@ class FunctionMixin(PyobjMixin):
     def _repr_failure_py(self, excinfo, style="long"):
         if excinfo.errisinstance(fail.Exception):
             if not excinfo.value.pytrace:
-                return py._builtin._totext(excinfo.value)
+                return six.text_type(excinfo.value)
         return super(FunctionMixin, self)._repr_failure_py(excinfo, style=style)
 
     def repr_failure(self, excinfo, outerr=None):