Precompiled regex simple diff

deepdiff/diff.py

@@ -13,6 +13,7 @@
 from math import isclose as is_close
 from collections.abc import Mapping, Iterable, Sequence
 from collections import defaultdict
+from inspect import getmembers
 from itertools import zip_longest
 from ordered_set import OrderedSet
 from deepdiff.helper import (strings, bytes_type, numbers, uuids, datetimes, ListItemRemovedOrAdded, notpresent,
@@ -415,20 +416,25 @@ def _diff_enum(self, level, parents_ids=frozenset(), local_tree=None):
 
     def _diff_obj(self, level, parents_ids=frozenset(), is_namedtuple=False, local_tree=None):
         """Difference of 2 objects"""
+        processing_error = False
         try:
             if is_namedtuple:
                 t1 = level.t1._asdict()
                 t2 = level.t2._asdict()
-            else:
+            elif all('__dict__' in dir(t) for t in level):
                 t1 = detailed__dict__(level.t1, ignore_private_variables=self.ignore_private_variables)
                 t2 = detailed__dict__(level.t2, ignore_private_variables=self.ignore_private_variables)
-        except AttributeError:
-            try:
+            elif all('__slots__' in dir(t) for t in level):
                 t1 = self._dict_from_slots(level.t1)
                 t2 = self._dict_from_slots(level.t2)
-            except AttributeError:
-                self._report_result('unprocessed', level, local_tree=local_tree)
-                return
+            else:
+                t1 = {k: v for k, v in getmembers(level.t1) if not callable(v)}
+                t2 = {k: v for k, v in getmembers(level.t2) if not callable(v)}
+        except AttributeError:
+            processing_error = True
+        if processing_error is True:
+            self._report_result('unprocessed', level, local_tree=local_tree)
+            return
 
         self._diff_dict(
             level,
@@ -874,7 +880,8 @@ def _diff_by_forming_pairs_and_comparing_one_by_one(
                     x,
                     y,
                     child_relationship_class=child_relationship_class,
-                    child_relationship_param=j)
+                    child_relationship_param=j
+                )
                 self._diff(next_level, parents_ids_added, local_tree=local_tree)
 
     def _diff_ordered_iterable_by_difflib(
@@ -1527,7 +1534,7 @@ def _diff(self, level, parents_ids=frozenset(), _original_type=None, local_tree=
         if isinstance(level.t1, booleans):
             self._diff_booleans(level, local_tree=local_tree)
 
-        if isinstance(level.t1, strings):
+        elif isinstance(level.t1, strings):
             self._diff_str(level, local_tree=local_tree)
 
         elif isinstance(level.t1, datetimes):

deepdiff/model.py

@@ -577,6 +577,10 @@ def __setattr__(self, key, value):
         else:
             self.__dict__[key] = value
 
+    def __iter__(self):
+        yield self.t1
+        yield self.t2
+
     @property
     def repetition(self):
         return self.additional['repetition']

tests/test_diff_text.py

@@ -2,6 +2,7 @@
 import datetime
 import pytest
 import logging
+import re
 import uuid
 from enum import Enum
 from typing import List
@@ -551,6 +552,64 @@ class MyEnum(Enum):
         }
         assert ddiff == result
 
+    def test_precompiled_regex(self):
+
+        pattern_1 = re.compile('foo')
+        pattern_2 = re.compile('foo')
+        pattern_3 = re.compile('foo', flags=re.I)
+        pattern_4 = re.compile('(foo)')
+        pattern_5 = re.compile('bar')
+
+        # same object
+        ddiff = DeepDiff(pattern_1, pattern_1)
+        result = {}
+        assert ddiff == result
+
+        # same pattern, different object
+        ddiff = DeepDiff(pattern_1, pattern_2)
+        result = {}
+        assert ddiff == result
+
+        # same pattern, different flags
+        ddiff = DeepDiff(pattern_1, pattern_3)
+        result = {
+            'values_changed': {
+                'root.flags': {
+                    'new_value': 34,
+                    'old_value': 32,
+                },
+            }
+        }
+        assert ddiff == result
+
+        # same pattern, different groups
+        ddiff = DeepDiff(pattern_1, pattern_4)
+        result = {
+            'values_changed': {
+                'root.pattern': {
+                    'new_value': '(foo)',
+                    'old_value': 'foo',
+                },
+                'root.groups': {
+                    'new_value': 1,
+                    'old_value': 0,
+                },
+            }
+        }
+        assert ddiff == result
+
+        # different pattern
+        ddiff = DeepDiff(pattern_1, pattern_5)
+        result = {
+            'values_changed': {
+                'root.pattern': {
+                    'new_value': 'bar',
+                    'old_value': 'foo',
+                },
+            }
+        }
+        assert ddiff == result
+
     def test_custom_objects_change(self):
         t1 = CustomClass(1)
         t2 = CustomClass(2)
@@ -1803,4 +1862,3 @@ class Bar(PydanticBaseModel):
         diff = DeepDiff(t1, t2)
         expected = {'values_changed': {'root.stuff[0].thing': {'new_value': 2, 'old_value': 1}}}
         assert expected == diff
-