Fix doctests for pytest 4.0.1

ref:e31e67704ea29a2a3582fa688a5afe8ba9e00f6e

library/python/pytest/plugins/collection.py

@@ -1,5 +1,4 @@
 import sys
-import traceback
 
 import py
 
@@ -28,50 +27,20 @@ def _getobj(self):
         return sys.modules[module_name]
 
 
-class DoctestItem(_pytest.doctest.DoctestItem):
-    def repr_failure(self, excinfo):
-        import doctest
-        if excinfo.errisinstance((doctest.DocTestFailure, doctest.UnexpectedException)):
-            doctestfailure = excinfo.value
-            example = doctestfailure.example
-            test = doctestfailure.test
-            filename = test.filename
-            if test.lineno is None:
-                lineno = None
-            else:
-                lineno = test.lineno + example.lineno + 1
-            message = excinfo.type.__name__
-            reprlocation = _pytest.doctest.ReprFileLocation(filename, lineno, message)
-            checker = doctest.OutputChecker()
-            lines = []
-            indent = '>>>'
-            for line in example.source.splitlines():
-                lines.append('%s %s' % (indent, line))
-                indent = '...'
-            if excinfo.errisinstance(doctest.DocTestFailure):
-                lines += checker.output_difference(example, doctestfailure.got, doctest.REPORT_UDIFF).split("\n")
-            else:
-                inner_excinfo = py.code.ExceptionInfo(excinfo.value.exc_info)
-                lines += ["UNEXPECTED EXCEPTION: %s" % repr(inner_excinfo.value)]
-                lines += traceback.format_exception(*excinfo.value.exc_info)
-            return _pytest.doctest.ReprFailDoctest(reprlocation, lines)
-        else:
-            return super(DoctestItem, self).repr_failure(excinfo)
-
-
 class DoctestModule(LoadedModule):
 
     def collect(self):
-        if sys.version_info[0] > 2:  # XXX Fix doctests for python3
-            return
         import doctest
-        finder = doctest.DocTestFinder()
+
         module = self._getobj()
+        # uses internal doctest module parsing mechanism
+        finder = doctest.DocTestFinder()
         optionflags = _pytest.doctest.get_optionflags(self)
         runner = doctest.DebugRunner(verbose=0, optionflags=optionflags)
+
         for test in finder.find(module, self.name[:-(len(".py"))]):
             if test.examples:  # skip empty doctests
-                yield DoctestItem(test.name, self, runner, test)
+                yield _pytest.doctest.DoctestItem(test.name, self, runner, test)
 
 
 class CollectionPlugin(object):