Tests for rich logging, apply ruff formatting

tests/test_format_diff.py

@@ -1,4 +1,4 @@
-from kanta.logging import format_diff
+from kanta.logging import _ADD, _DELETE, format_diff
 
 
 def test_add():
@@ -6,6 +6,28 @@ def test_add():
     assert any("name" in line for line in lines)
 
 
+def test_add_path_is_green():
+    lines = format_diff({"name": "Alice"}, previous={})
+    assert any(_ADD in line for line in lines)
+
+
+def test_nested_add_path_final_element_is_green():
+    lines = format_diff({"users": {"alice": 1}}, previous={"users": {}})
+    assert any(_ADD in line and "alice" in line for line in lines)
+
+
+def test_update_path_not_colored_as_add():
+    lines = format_diff({"name": "Bob"}, previous={"name": "Alice"})
+    assert lines
+    assert all(_ADD not in line for line in lines)
+
+
+def test_delete_path_not_colored_as_add():
+    lines = format_diff({"$delete": ["old_key"]}, previous={"old_key": 1})
+    assert any(_DELETE in line for line in lines)
+    assert all(_ADD not in line for line in lines)
+
+
 def test_update():
     lines = format_diff({"name": "Bob"}, previous={"name": "Alice"})
     assert any("Bob" in line for line in lines)