add callable group_by tests

Author: echan5

tests/test_diff_group_by.py

@@ -0,0 +1,59 @@
+"""Tests for the group_by parameter of Deepdiff"""
+
+import pytest
+
+from deepdiff import DeepDiff
+
+
+class TestGetKeyForGroupBy:
+    def test_group_by_string(self):
+        """Test where group_by is a single key (string)."""
+        row = {'first': 'John', 'middle': 'Joe', 'last': 'Smith'}
+        group_by = 'first'
+        item_name = 't1'
+        actual = DeepDiff._get_key_for_group_by(row, group_by, item_name)
+        expected = 'John'
+
+        assert actual == expected
+
+    def test_group_by_callable(self):
+        """Test where group_by is callable."""
+        row = {'id': 123, 'demographics': {'names': {'first': 'John', 'middle': 'Joe', 'last': 'Smith'}}}
+        group_by = lambda x: x['demographics']['names']['first']
+        item_name = 't1'
+        actual = DeepDiff._get_key_for_group_by(row, group_by, item_name)
+        expected = 'John'
+        assert actual == expected
+
+    def test_group_by_key_error(self):
+        """Test where group_by is a key that is not in the row."""
+        row = {'id': 123, 'demographics': {'names': {'first': 'John', 'middle': 'Joe', 'last': 'Smith'}}}
+        group_by = 'someotherkey'
+        item_name = 't1'
+        with pytest.raises(KeyError):
+            DeepDiff._get_key_for_group_by(row, group_by, item_name)
+
+
+class TestGroupBy:
+    def test_group_by_callable(self):
+        """Test where group_by is a callable."""
+        t1 = [
+            {'id': 'AA', 'demographics': {'names': {'first': 'Joe', 'middle': 'John', 'last': 'Nobody'}}},
+            {'id': 'BB', 'demographics': {'names': {'first': 'James', 'middle': 'Joyce', 'last': 'Blue'}}},
+            {'id': 'CC', 'demographics': {'names': {'first': 'Mike', 'middle': 'Mark', 'last': 'Apple'}}},
+        ]
+
+        t2 = [
+            {'id': 'AA', 'demographics': {'names': {'first': 'Joe', 'middle': 'John', 'last': 'Nobody'}}},
+            {'id': 'BB', 'demographics': {'names': {'first': 'James', 'middle': 'Joyce', 'last': 'Brown'}}},
+            {'id': 'CC', 'demographics': {'names': {'first': 'Mike', 'middle': 'Charles', 'last': 'Apple'}}},
+        ]
+
+        actual = DeepDiff(t1, t2, group_by=lambda x: x['demographics']['names']['first'])
+        expected = {
+            'values_changed': {
+                "root['James']['demographics']['names']['last']": {'new_value': 'Brown', 'old_value': 'Blue'},
+                "root['Mike']['demographics']['names']['middle']": {'new_value': 'Charles', 'old_value': 'Mark'},
+            },
+        }
+        assert actual == expected