refactor: apply pylint rule fixes, add an inline optimization for `…

…_selection`

`param_kwds` in `_selection` triggered `PLR6201`. Instead rewrote as a dictcomp.

altair/utils/_transformed_data.py

@@ -183,7 +183,7 @@ def name_views(
         chart, (_chart_class_mapping[Chart], _chart_class_mapping[FacetChart])
     ):
         if chart.name not in exclude:
-            if chart.name in (None, Undefined):
+            if chart.name in {None, Undefined}:
                 # Add name since none is specified
                 chart.name = Chart._get_name()
             return [chart.name]

altair/utils/core.py

@@ -211,27 +211,27 @@ def infer_vegalite_type(
     """
     typ = infer_dtype(data, skipna=False)
 
-    if typ in [
+    if typ in {
         "floating",
         "mixed-integer-float",
         "integer",
         "mixed-integer",
         "complex",
-    ]:
+    }:
         return "quantitative"
     elif typ == "categorical" and hasattr(data, "cat") and data.cat.ordered:
         return ("ordinal", data.cat.categories.tolist())
-    elif typ in ["string", "bytes", "categorical", "boolean", "mixed", "unicode"]:
+    elif typ in {"string", "bytes", "categorical", "boolean", "mixed", "unicode"}:
         return "nominal"
-    elif typ in [
+    elif typ in {
         "datetime",
         "datetime64",
         "timedelta",
         "timedelta64",
         "date",
         "time",
         "period",
-    ]:
+    }:
         return "temporal"
     else:
         warnings.warn(
@@ -674,9 +674,9 @@ def infer_vegalite_type_for_dfi_column(
         categories_column = column.describe_categorical["categories"]
         categories_array = column_to_array(categories_column)
         return "ordinal", categories_array.to_pylist()
-    if kind in (DtypeKind.STRING, DtypeKind.CATEGORICAL, DtypeKind.BOOL):
+    if kind in {DtypeKind.STRING, DtypeKind.CATEGORICAL, DtypeKind.BOOL}:
         return "nominal"
-    elif kind in (DtypeKind.INT, DtypeKind.UINT, DtypeKind.FLOAT):
+    elif kind in {DtypeKind.INT, DtypeKind.UINT, DtypeKind.FLOAT}:
         return "quantitative"
     elif kind == DtypeKind.DATETIME:
         return "temporal"

altair/utils/data.py

@@ -17,6 +17,7 @@
 
 
 from typing import Protocol, TypedDict, Literal
+import locale
 
 
 if TYPE_CHECKING:
@@ -186,7 +187,7 @@ def to_json(
     data_json = _data_to_json_string(data)
     data_hash = _compute_data_hash(data_json)
     filename = filename.format(prefix=prefix, hash=data_hash, extension=extension)
-    Path(filename).write_text(data_json)
+    Path(filename).write_text(data_json, encoding=locale.getpreferredencoding(False))
     return {"url": str(Path(urlpath, filename)), "format": {"type": "json"}}
 
 
@@ -202,7 +203,7 @@ def to_csv(
     data_csv = _data_to_csv_string(data)
     data_hash = _compute_data_hash(data_csv)
     filename = filename.format(prefix=prefix, hash=data_hash, extension=extension)
-    Path(filename).write_text(data_csv)
+    Path(filename).write_text(data_csv, encoding=locale.getpreferredencoding(False))
     return {"url": str(Path(urlpath, filename)), "format": {"type": "csv"}}
 
 

altair/utils/html.py

@@ -266,7 +266,7 @@ def spec_to_html(
 
     mode = embed_options.setdefault("mode", mode)
 
-    if mode not in ["vega", "vega-lite"]:
+    if mode not in {"vega", "vega-lite"}:
         msg = "mode must be either 'vega' or 'vega-lite'"
         raise ValueError(msg)
 

altair/utils/mimebundle.py

@@ -77,7 +77,7 @@ def spec_to_mimebundle(
 
     embed_options = preprocess_embed_options(final_embed_options)
 
-    if format in ["png", "svg", "pdf", "vega"]:
+    if format in {"png", "svg", "pdf", "vega"}:
         format = cast(Literal["png", "svg", "pdf", "vega"], format)
         return _spec_to_mimebundle_with_engine(
             spec,

altair/utils/save.py

@@ -171,7 +171,7 @@ def perform_save():
             write_file_or_filename(
                 fp, mimebundle["text/html"], mode="w", encoding=encoding
             )
-        elif format in ["png", "svg", "pdf", "vega"]:
+        elif format in {"png", "svg", "pdf", "vega"}:
             mimebundle = spec_to_mimebundle(
                 spec=spec,
                 format=format,

altair/utils/schemapi.py

@@ -220,20 +220,15 @@ def _prepare_refs(d: Dict[str, Any]) -> Dict[str, Any]:
         for key, value in d.items():
             if key == "$ref":
                 d[key] = _VEGA_LITE_ROOT_URI + d[key]
-            else:
-                # $ref values can only be nested in dictionaries or lists
-                # as the passed in `d` dictionary comes from the Vega-Lite json schema
-                # and in json we only have arrays (-> lists in Python) and objects
-                # (-> dictionaries in Python) which we need to iterate through.
-                if isinstance(value, dict):
-                    d[key] = _prepare_refs(value)
-                elif isinstance(value, list):
-                    prepared_values = []
-                    for v in value:
-                        if isinstance(v, dict):
-                            v = _prepare_refs(v)
-                        prepared_values.append(v)
-                    d[key] = prepared_values
+            elif isinstance(value, dict):
+                d[key] = _prepare_refs(value)
+            elif isinstance(value, list):
+                prepared_values = []
+                for v in value:
+                    if isinstance(v, dict):
+                        v = _prepare_refs(v)
+                    prepared_values.append(v)
+                d[key] = prepared_values
         return d
 
     schema = _prepare_refs(schema)
@@ -616,7 +611,7 @@ def _format_params_as_table(param_dict_keys: Iterable[str]) -> str:
             *[
                 (name, len(name))
                 for name in param_dict_keys
-                if name not in ["kwds", "self"]
+                if name not in {"kwds", "self"}
             ]
         )
         # Worst case scenario with the same longest param name in the same
@@ -712,7 +707,7 @@ def _get_default_error_message(
         # 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"):
+            if validator not in {"enum", "type"}:
                 message += "\n".join([e.message for e in errors])
 
         return message
@@ -762,7 +757,7 @@ def __init__(self, *args: Any, **kwds: Any) -> None:
         if kwds:
             assert len(args) == 0
         else:
-            assert len(args) in [0, 1]
+            assert len(args) in {0, 1}
 
         # use object.__setattr__ because we override setattr below.
         object.__setattr__(self, "_args", args)
@@ -942,7 +937,7 @@ def to_dict(
             # when a non-ordinal data type is specifed manually
             # or if the encoding channel does not support sorting
             if "sort" in parsed_shorthand and (
-                "sort" not in kwds or kwds["type"] not in ["ordinal", Undefined]
+                "sort" not in kwds or kwds["type"] not in {"ordinal", Undefined}
             ):
                 parsed_shorthand.pop("sort")
 
@@ -954,7 +949,7 @@ def to_dict(
                 }
             )
             kwds = {
-                k: v for k, v in kwds.items() if k not in [*list(ignore), "shorthand"]
+                k: v for k, v in kwds.items() if k not in {*list(ignore), "shorthand"}
             }
             if "mark" in kwds and isinstance(kwds["mark"], str):
                 kwds["mark"] = {"type": kwds["mark"]}

altair/vegalite/data.py

@@ -27,7 +27,7 @@ class DataTransformerRegistry(_DataTransformerRegistry):
     def disable_max_rows(self) -> PluginEnabler:
         """Disable the MaxRowsError."""
         options = self.options
-        if self.active in ("default", "vegafusion"):
+        if self.active in {"default", "vegafusion"}:
             options = options.copy()
             options["max_rows"] = None
         return self.enable(**options)

altair/vegalite/v5/api.py

@@ -461,18 +461,16 @@ def _selection(
     type: Union[Literal["interval", "point"], UndefinedType] = Undefined, **kwds
 ) -> Parameter:
     # We separate out the parameter keywords from the selection keywords
-    param_kwds = {}
 
-    for kwd in {"name", "bind", "value", "empty", "init", "views"}:
-        if kwd in kwds:
-            param_kwds[kwd] = kwds.pop(kwd)
+    select_kwds = {"name", "bind", "value", "empty", "init", "views"}
+    param_kwds = {key: kwds.pop(key) for key in select_kwds & kwds.keys()}
 
     select: Union[core.IntervalSelectionConfig, core.PointSelectionConfig]
     if type == "interval":
         select = core.IntervalSelectionConfig(type=type, **kwds)
     elif type == "point":
         select = core.PointSelectionConfig(type=type, **kwds)
-    elif type in ["single", "multi"]:
+    elif type in {"single", "multi"}:
         select = core.PointSelectionConfig(type="point", **kwds)
         warnings.warn(
             """The types 'single' and 'multi' are now
@@ -928,7 +926,7 @@ def to_dict(
         """
 
         # Validate format
-        if format not in ("vega-lite", "vega"):
+        if format not in {"vega-lite", "vega"}:
             msg = f'The format argument must be either "vega-lite" or "vega". Received {format!r}'
             raise ValueError(msg)
 
@@ -998,15 +996,14 @@ def to_dict(
                 raise ValueError(msg)
             else:
                 return _compile_with_vegafusion(vegalite_spec)
+        elif format == "vega":
+            plugin = vegalite_compilers.get()
+            if plugin is None:
+                msg = "No active vega-lite compiler plugin found"
+                raise ValueError(msg)
+            return plugin(vegalite_spec)
         else:
-            if format == "vega":
-                plugin = vegalite_compilers.get()
-                if plugin is None:
-                    msg = "No active vega-lite compiler plugin found"
-                    raise ValueError(msg)
-                return plugin(vegalite_spec)
-            else:
-                return vegalite_spec
+            return vegalite_spec
 
     def to_json(
         self,
@@ -1242,7 +1239,6 @@ def save(
                 save(**kwds)
         else:
             save(**kwds)
-        return
 
     # Fallback for when rendering fails; the full repr is too long to be
     # useful in nearly all cases.
@@ -2448,10 +2444,9 @@ def transform_timeunit(
         """
         if as_ is Undefined:
             as_ = kwargs.pop("as", Undefined)
-        else:
-            if "as" in kwargs:
-                msg = "transform_timeunit: both 'as_' and 'as' passed as arguments."
-                raise ValueError(msg)
+        elif "as" in kwargs:
+            msg = "transform_timeunit: both 'as_' and 'as' passed as arguments."
+            raise ValueError(msg)
         if as_ is not Undefined:
             dct = {"as": as_, "timeUnit": timeUnit, "field": field}
             self = self._add_transform(core.TimeUnitTransform(**dct))  # type: ignore[arg-type]
@@ -3271,7 +3266,7 @@ def repeat(
     -------
     repeat : RepeatRef object
     """
-    if repeater not in ["row", "column", "repeat", "layer"]:
+    if repeater not in {"row", "column", "repeat", "layer"}:
         msg = "repeater must be one of ['row', 'column', 'repeat', 'layer']"
         raise ValueError(msg)
     return core.RepeatRef(repeat=repeater)
@@ -3819,11 +3814,8 @@ def remove_data(subchart):
         if subdata is not Undefined and all(c.data is subdata for c in subcharts):
             data = subdata
             subcharts = [remove_data(c) for c in subcharts]
-    else:
-        # Top level has data; subchart data must be either
-        # undefined or identical to proceed.
-        if all(c.data is Undefined or c.data is data for c in subcharts):
-            subcharts = [remove_data(c) for c in subcharts]
+    elif all(c.data is Undefined or c.data is data for c in subcharts):
+        subcharts = [remove_data(c) for c in subcharts]
 
     return data, subcharts
 
@@ -4053,17 +4045,14 @@ def remove_prop(subchart, prop):
             else:
                 msg = f"There are inconsistent values {values} for {prop}"
                 raise ValueError(msg)
+        elif all(
+            getattr(c, prop, Undefined) is Undefined or c[prop] == chart[prop]
+            for c in subcharts
+        ):
+            output_dict[prop] = chart[prop]
         else:
-            # Top level has this prop; subchart must either not have the prop
-            # or it must be Undefined or identical to proceed.
-            if all(
-                getattr(c, prop, Undefined) is Undefined or c[prop] == chart[prop]
-                for c in subcharts
-            ):
-                output_dict[prop] = chart[prop]
-            else:
-                msg = f"There are inconsistent values {values} for {prop}"
-                raise ValueError(msg)
+            msg = f"There are inconsistent values {values} for {prop}"
+            raise ValueError(msg)
         subcharts = [remove_prop(c, prop) for c in subcharts]
 
     return output_dict, subcharts

sphinxext/altairgallery.py

@@ -26,6 +26,7 @@
 from altair.utils.execeval import eval_block
 from tests.examples_arguments_syntax import iter_examples_arguments_syntax
 from tests.examples_methods_syntax import iter_examples_methods_syntax
+import locale
 
 
 EXAMPLE_MODULE = "altair.examples"
@@ -158,7 +159,7 @@ def save_example_pngs(examples, image_dir, make_thumbnails=True):
     hash_file = os.path.join(image_dir, "_image_hashes.json")
 
     if os.path.exists(hash_file):
-        with open(hash_file) as f:
+        with open(hash_file, encoding=locale.getpreferredencoding(False)) as f:
             hashes = json.load(f)
     else:
         hashes = {}
@@ -183,7 +184,7 @@ def save_example_pngs(examples, image_dir, make_thumbnails=True):
                 warnings.warn("Unable to save image: using generic image", stacklevel=1)
                 create_generic_image(image_file)
 
-            with open(hash_file, "w") as f:
+            with open(hash_file, "w", encoding=locale.getpreferredencoding(False)) as f:
                 json.dump(hashes, f)
 
         if make_thumbnails:
@@ -197,7 +198,7 @@ def save_example_pngs(examples, image_dir, make_thumbnails=True):
                 create_thumbnail(image_file, thumb_file, **params)
 
     # Save hashes so we know whether we need to re-generate plots
-    with open(hash_file, "w") as f:
+    with open(hash_file, "w", encoding=locale.getpreferredencoding(False)) as f:
         json.dump(hashes, f)
 
 
@@ -343,7 +344,8 @@ def main(app):
             examples=examples_toc.items(),
             image_dir="/_static",
             gallery_ref=gallery_ref,
-        )
+        ),
+        encoding=locale.getpreferredencoding(False),
     )
 
     # save the images to file

tests/vegalite/v5/test_api.py

@@ -48,7 +48,7 @@ def _make_chart_type(chart_type):
         )
     )
 
-    if chart_type in ["layer", "hconcat", "vconcat", "concat"]:
+    if chart_type in {"layer", "hconcat", "vconcat", "concat"}:
         func = getattr(alt, chart_type)
         return func(base.mark_square(), base.mark_circle())
     elif chart_type == "facet":
@@ -289,14 +289,14 @@ def test_selection_expression():
 @pytest.mark.parametrize("format", ["html", "json", "png", "svg", "pdf", "bogus"])
 @pytest.mark.parametrize("engine", ["vl-convert"])
 def test_save(format, engine, basic_chart):
-    if format in ["pdf", "png"]:
+    if format in {"pdf", "png"}:
         out = io.BytesIO()
         mode = "rb"
     else:
         out = io.StringIO()
         mode = "r"
 
-    if format in ["svg", "png", "pdf", "bogus"] and engine == "vl-convert":
+    if format in {"svg", "png", "pdf", "bogus"} and engine == "vl-convert":
         if format == "bogus":
             with pytest.raises(ValueError) as err:
                 basic_chart.save(out, format=format, engine=engine)
@@ -605,9 +605,10 @@ def test_transforms():
 
     # kwargs don't maintain order in Python < 3.6, so window list can
     # be reversed
-    assert chart.transform == [
-        alt.WindowTransform(frame=[None, 0], window=window)
-    ] or chart.transform == [alt.WindowTransform(frame=[None, 0], window=window[::-1])]
+    assert chart.transform in (
+        [alt.WindowTransform(frame=[None, 0], window=window)],
+        [alt.WindowTransform(frame=[None, 0], window=window[::-1])],
+    )
 
 
 def test_filter_transform_selection_predicates():