ci(ruff): Enforce the default C901 complexity (#3531)

altair/jupyter/jupyter_chart.py

@@ -218,7 +218,7 @@ def __init__(
         )
 
     @traitlets.observe("chart")
-    def _on_change_chart(self, change):
+    def _on_change_chart(self, change):  # noqa: C901
         """Updates the JupyterChart's internal state when the wrapped Chart instance changes."""
         new_chart = change.new
         selection_watches = []

altair/utils/core.py

@@ -319,7 +319,7 @@ def numpy_is_subtype(dtype: Any, subtype: Any) -> bool:
         return False
 
 
-def sanitize_pandas_dataframe(df: pd.DataFrame) -> pd.DataFrame:
+def sanitize_pandas_dataframe(df: pd.DataFrame) -> pd.DataFrame:  # noqa: C901
     """
     Sanitize a DataFrame to prepare it for serialization.
 
@@ -502,7 +502,7 @@ def to_eager_narwhals_dataframe(data: IntoDataFrame) -> nw.DataFrame[Any]:
     return data_nw
 
 
-def parse_shorthand(
+def parse_shorthand(  # noqa: C901
     shorthand: dict[str, Any] | str,
     data: pd.DataFrame | DataFrameLike | None = None,
     parse_aggregates: bool = True,

altair/utils/save.py

@@ -140,8 +140,7 @@ def save(
             version="5.0.0",
         )
 
-    if json_kwds is None:
-        json_kwds = {}
+    json_kwds = json_kwds or {}
     encoding = kwargs.get("encoding", "utf-8")
     format = set_inspect_format_argument(format, fp, inline)  # type: ignore[assignment]
 

altair/utils/schemapi.py

@@ -497,7 +497,7 @@ def _from_array_like(obj: Iterable[Any], /) -> list[Any]:
         return list(obj)
 
 
-def _todict(obj: Any, context: dict[str, Any] | None, np_opt: Any, pd_opt: Any) -> Any:
+def _todict(obj: Any, context: dict[str, Any] | None, np_opt: Any, pd_opt: Any) -> Any:  # noqa: C901
     """Convert an object to a dict representation."""
     if np_opt is not None:
         np = np_opt
@@ -761,10 +761,12 @@ def _get_default_error_message(
         # Add unformatted messages of any remaining errors which were not
         # considered so far. This is not expected to be used but more exists
         # as a fallback for cases which were not known during development.
-        for validator, errors in errors_by_validator.items():
-            if validator not in {"enum", "type"}:
-                message += "\n".join([e.message for e in errors])
-
+        it = (
+            "\n".join(e.message for e in errors)
+            for validator, errors in errors_by_validator.items()
+            if validator not in {"enum", "type"}
+        )
+        message += "".join(it)
         return message
 
 
@@ -868,7 +870,7 @@ def __init__(self, *args: Any, **kwds: Any) -> None:
         if DEBUG_MODE and self._class_is_valid_at_instantiation:
             self.to_dict(validate=True)
 
-    def copy(
+    def copy(  # noqa: C901
         self, deep: bool | Iterable[Any] = True, ignore: list[str] | None = None
     ) -> Self:
         """

altair/vegalite/v5/api.py

@@ -1725,7 +1725,7 @@ class TopLevelMixin(mixins.ConfigMethodMixin):
     _class_is_valid_at_instantiation: bool = False
     data: Any
 
-    def to_dict(
+    def to_dict(  # noqa: C901
         self,
         validate: bool = True,
         *,
@@ -3876,7 +3876,8 @@ def _check_if_valid_subspec(
             raise ValueError(err.format(attr, classname))
 
 
-def _check_if_can_be_layered(spec: LayerType | dict[str, Any]) -> None:
+# C901 fixed in https://github.com/vega/altair/pull/3520
+def _check_if_can_be_layered(spec: LayerType | dict[str, Any]) -> None:  # noqa: C901
     """Check if the spec can be layered."""
 
     def _get(spec: LayerType | dict[str, Any], attr: str) -> Any:
@@ -4715,7 +4716,7 @@ def _remove_duplicate_params(layer: list[ChartType]) -> list[ChartType]:
     return subcharts
 
 
-def _combine_subchart_params(
+def _combine_subchart_params(  # noqa: C901
     params: Optional[Sequence[_Parameter]], subcharts: list[ChartType]
 ) -> tuple[Optional[Sequence[_Parameter]], list[ChartType]]:
     if utils.is_undefined(params):
@@ -4852,7 +4853,7 @@ def _repeat_names(
     return params_named
 
 
-def _remove_layer_props(
+def _remove_layer_props(  # noqa: C901
     chart: LayerChart, subcharts: list[ChartType], layer_props: Iterable[str]
 ) -> tuple[dict[str, Any], list[ChartType]]:
     def remove_prop(subchart: ChartType, prop: str) -> ChartType:

pyproject.toml

@@ -313,6 +313,8 @@ select = [
     "ANN",
     # unsorted-imports
     "I001",
+    # complex-structure
+    "C901",
 ]
 ignore = [  
     # Whitespace before ':'
@@ -360,7 +362,7 @@ ignore = [
 ]
 # https://docs.astral.sh/ruff/settings/#lintpydocstyle
 pydocstyle={ convention="numpy" }
-mccabe={ max-complexity=18 }
+mccabe={ max-complexity=10 }
 
 [tool.ruff.lint.isort]
 classes = ["expr", "datum"]
@@ -386,6 +388,8 @@ See https://github.com/vega/altair/pull/3449
 [tool.ruff.lint.per-file-ignores]
 # Only enforce type annotation rules on public api
 "!altair/vegalite/v5/api.py" = ["ANN"]
+# Allow complex if/elif branching during tests
+"tests/**/*.py"= ["C901"]
 
 
 [tool.ruff.format]

tools/schemapi/schemapi.py

@@ -495,7 +495,7 @@ def _from_array_like(obj: Iterable[Any], /) -> list[Any]:
         return list(obj)
 
 
-def _todict(obj: Any, context: dict[str, Any] | None, np_opt: Any, pd_opt: Any) -> Any:
+def _todict(obj: Any, context: dict[str, Any] | None, np_opt: Any, pd_opt: Any) -> Any:  # noqa: C901
     """Convert an object to a dict representation."""
     if np_opt is not None:
         np = np_opt
@@ -759,10 +759,12 @@ def _get_default_error_message(
         # Add unformatted messages of any remaining errors which were not
         # considered so far. This is not expected to be used but more exists
         # as a fallback for cases which were not known during development.
-        for validator, errors in errors_by_validator.items():
-            if validator not in {"enum", "type"}:
-                message += "\n".join([e.message for e in errors])
-
+        it = (
+            "\n".join(e.message for e in errors)
+            for validator, errors in errors_by_validator.items()
+            if validator not in {"enum", "type"}
+        )
+        message += "".join(it)
         return message
 
 
@@ -866,7 +868,7 @@ def __init__(self, *args: Any, **kwds: Any) -> None:
         if DEBUG_MODE and self._class_is_valid_at_instantiation:
             self.to_dict(validate=True)
 
-    def copy(
+    def copy(  # noqa: C901
         self, deep: bool | Iterable[Any] = True, ignore: list[str] | None = None
     ) -> Self:
         """

tools/schemapi/utils.py

@@ -386,7 +386,7 @@ def get_python_type_representation(
         return_as_str: Literal[False] = ...,
         additional_type_hints: list[str] | None = ...,
     ) -> list[str]: ...
-    def get_python_type_representation(
+    def get_python_type_representation(  # noqa: C901
         self,
         for_type_hints: bool = False,
         return_as_str: bool = True,
@@ -682,7 +682,7 @@ def __call__(self, s: str) -> str:
 rst_parse: RSTParse = RSTParse(RSTRenderer())
 
 
-def indent_docstring(
+def indent_docstring(  # noqa: C901
     lines: list[str], indent_level: int, width: int = 100, lstrip=True
 ) -> str:
     """Indent a docstring for use in generated code."""