adding - v4-0-8: Adding ignore_nan_inequality for float('nan')

Author: seperman

README.md

@@ -417,6 +417,7 @@ And then running
 
 # ChangeLog
 
+- v4-0-8: Adding ignore_nan_inequality for float('nan')
 - v4-0-7: Hashing of the number 1 vs. True
 - v4-0-6: found a tiny bug in Python formatting of numbers in scientific notation. Added a workaround.
 - v4-0-5: Fixing number diffing. Adding number_format_notation and number_to_string_func.

deepdiff/diff.py

@@ -59,6 +59,7 @@ def __init__(self,
                  ignore_type_subclasses=False,
                  ignore_string_case=False,
                  number_to_string_func=None,
+                 ignore_nan_inequality=False,
                  verbose_level=1,
                  view=TEXT_VIEW,
                  hasher=None,
@@ -69,7 +70,7 @@ def __init__(self,
                 "The valid parameters are ignore_order, report_repetition, significant_digits, "
                 "number_format_notation, exclude_paths, exclude_types, exclude_regex_paths, ignore_type_in_groups, "
                 "ignore_string_type_changes, ignore_numeric_type_changes, ignore_type_subclasses, "
-                "number_to_string_func, verbose_level, view, and hasher.") % ', '.join(kwargs.keys()))
+                "ignore_nan_inequality, number_to_string_func, verbose_level, view, and hasher.") % ', '.join(kwargs.keys()))
 
         self.ignore_order = ignore_order
         self.ignore_type_in_groups = self.get_ignore_types_in_groups(
@@ -88,6 +89,7 @@ def __init__(self,
         self.type_check_func = type_is_subclass_of_type_group if ignore_type_subclasses else type_in_type_group
         self.ignore_string_case = ignore_string_case
         self.number_to_string = number_to_string_func or number_to_string
+        self.ignore_nan_inequality = ignore_nan_inequality
         self.hashes = {}
         self.hasher = hasher
 
@@ -613,6 +615,9 @@ def __diff(self, level, parents_ids=frozenset({})):
                 self.__diff_types(level)
                 return
 
+        if self.ignore_nan_inequality and isinstance(level.t1, float) and str(level.t1) == str(level.t2) == 'nan':
+            return
+
         if isinstance(level.t1, strings):
             self.__diff_str(level)
 

docs/index.rst

@@ -281,6 +281,7 @@ Indices and tables
 Changelog
 =========
 
+- v4-0-8: Adding ignore_nan_inequality for float('nan')
 - v4-0-7: Hashing of the number 1 vs. True
 - v4-0-6: found a tiny bug in Python formatting of numbers in scientific notation. Added a workaround.
 - v4-0-5: Fixing number diffing. Adding number_format_notation and number_to_string_func.

tests/test_diff_text.py

@@ -1723,3 +1723,11 @@ def test_bool_vs_number(self):
 
         ddiff = DeepDiff(t1, t2, ignore_order=True)
         assert ddiff == {}
+
+    @pytest.mark.parametrize('t1, t2, params, expected_result', [
+        (float('nan'), float('nan'), {}, ['values_changed']),
+        (float('nan'), float('nan'), {'ignore_nan_inequality': True}, []),
+        ([1, float('nan')], [1, float('nan')], {'ignore_nan_inequality': True}, []),
+    ])
+    def test_ignore_nan_inequality(self, t1, t2, params, expected_result):
+        assert expected_result == list(DeepDiff(t1, t2, **params).keys())