✨ Add support for sorting data in insert_assert based on previous data (e.g. from a previous run) to minimize the diff

devtools/pytest_plugin.py

@@ -37,15 +37,42 @@ class ToReplace:
 insert_assert_summary: ContextVar[list[str]] = ContextVar('insert_assert_summary')
 
 
-def insert_assert(value: Any) -> int:
+def sort_data_from_source(source: Any, value: Any) -> Any:
+    if isinstance(value, dict) and isinstance(source, dict):
+        new_dict = {}
+        used_keys = set()
+        for k, v in source.items():
+            if k in value:
+                new_dict[k] = sort_data_from_source(v, value[k])
+            used_keys.add(k)
+        for k, v in value.items():
+            if k not in used_keys:
+                new_dict[k] = v
+        return new_dict
+    elif isinstance(value, list) and isinstance(source, list):
+        new_list: list[Any] = []
+        for i, v in enumerate(value):
+            if i < len(source):
+                new_list.append(sort_data_from_source(source[i], v))
+            else:
+                new_list.append(v)
+        return new_list
+    else:
+        return value
+
+
+def insert_assert(value: Any, prev: Any = None) -> int:
     call_frame: FrameType = sys._getframe(1)
     if sys.version_info < (3, 8):  # pragma: no cover
         raise RuntimeError('insert_assert() requires Python 3.8+')
-
+    if prev:
+        use_value = sort_data_from_source(prev, value)
+    else:
+        use_value = value
     format_code = load_black()
     ex = Source.for_frame(call_frame).executing(call_frame)
     if ex.node is None:  # pragma: no cover
-        python_code = format_code(str(custom_repr(value)))
+        python_code = format_code(str(custom_repr(use_value)))
         raise RuntimeError(
             f'insert_assert() was unable to find the frame from which it was called, called with:\n{python_code}'
         )
@@ -55,7 +82,7 @@ def insert_assert(value: Any) -> int:
     else:
         arg = ' '.join(map(str.strip, ex.source.asttokens().get_text(ast_arg).splitlines()))
 
-    python_code = format_code(f'# insert_assert({arg})\nassert {arg} == {custom_repr(value)}')
+    python_code = format_code(f'# insert_assert({arg})\nassert {arg} == {custom_repr(use_value)}')
 
     python_code = textwrap.indent(python_code, ex.node.col_offset * ' ')
     to_replace.append(ToReplace(Path(call_frame.f_code.co_filename), ex.node.lineno, ex.node.end_lineno, python_code))

tests/test_insert_assert.py

@@ -167,3 +167,76 @@ def test_string_assert(x, insert_assert):
     )
     captured = capsys.readouterr()
     assert '2 insert skipped because an assert statement on that line had already be inserted!\n' in captured.out
+
+
+def test_insert_assert_sort_data(pytester_pretty):
+    os.environ.pop('CI', None)
+    pytester_pretty.makeconftest(config)
+    test_file = pytester_pretty.makepyfile(
+        """
+def test_dict(insert_assert):
+    old_data = {
+        "foo": 1,
+        "bar": [
+            {"name": "Pydantic", "tags": ["validation", "json"]},
+            {"name": "FastAPI", "description": "Web API framework in Python"},
+            {"name": "SQLModel"},
+        ],
+        "baz": 3,
+    }
+    new_data = {
+        "bar": [
+            {
+                "description": "Data validation library",
+                "tags": ["validation", "json"],
+                "name": "Pydantic",
+            },
+            {"description": "Web API framework in Python", "name": "FastAPI"},
+            {"description": "DBs and Python", "name": "SQLModel"},
+            {"name": "ARQ"},
+        ],
+        "baz": 6,
+        "foo": 1,
+    }
+    insert_assert(new_data, old_data)
+"""
+    )
+    result = pytester_pretty.runpytest()
+    result.assert_outcomes(passed=1)
+    assert test_file.read_text() == (
+        """def test_dict(insert_assert):
+    old_data = {
+        "foo": 1,
+        "bar": [
+            {"name": "Pydantic", "tags": ["validation", "json"]},
+            {"name": "FastAPI", "description": "Web API framework in Python"},
+            {"name": "SQLModel"},
+        ],
+        "baz": 3,
+    }
+    new_data = {
+        "bar": [
+            {
+                "description": "Data validation library",
+                "tags": ["validation", "json"],
+                "name": "Pydantic",
+            },
+            {"description": "Web API framework in Python", "name": "FastAPI"},
+            {"description": "DBs and Python", "name": "SQLModel"},
+            {"name": "ARQ"},
+        ],
+        "baz": 6,
+        "foo": 1,
+    }
+    # insert_assert(new_data)
+    assert new_data == {
+        'foo': 1,
+        'bar': [
+            {'name': 'Pydantic', 'tags': ['validation', 'json'], 'description': 'Data validation library'},
+            {'name': 'FastAPI', 'description': 'Web API framework in Python'},
+            {'name': 'SQLModel', 'description': 'DBs and Python'},
+            {'name': 'ARQ'},
+        ],
+        'baz': 6,
+    }"""
+    )