ENH: add decimal and thousands args to Styler.format() (pandas-dev#40596)

Author: attack68

pandas/io/formats/style_render.py

@@ -12,6 +12,7 @@
  Sequence,
  Tuple,
  Union,
+ cast,
 )
 from uuid import uuid4
 
@@ -20,10 +21,7 @@
 from pandas._config import get_option
 
 from pandas._libs import lib
-from pandas._typing import (
- FrameOrSeriesUnion,
- TypedDict,
-)
+from pandas._typing import FrameOrSeriesUnion
 from pandas.compat._optional import import_optional_dependency
 
 from pandas.core.dtypes.generic import ABCSeries
@@ -47,14 +45,10 @@
 CSSPair = Tuple[str, Union[str, int, float]]
 CSSList = List[CSSPair]
 CSSProperties = Union[str, CSSList]
-
-
-class CSSDict(TypedDict):
- selector: str
- props: CSSProperties
-
-
-CSSStyles = List[CSSDict]
+CSSStyles = List[Dict[str, CSSProperties]] # = List[CSSDict]
+# class CSSDict(TypedDict): # available when TypedDict is valid in pandas
+# selector: str
+# props: CSSProperties
 
 
 class StylerRenderer:
@@ -108,10 +102,42 @@ def __init__(
  tuple[int, int], Callable[[Any], str]
  ] = defaultdict(lambda: partial(_default_formatter, precision=def_precision))
 
- def _render_html(self, **kwargs) -> str:
+ def render(self, **kwargs) -> str:
  """
- Renders the ``Styler`` including all applied styles to HTML.
- Generates a dict with necessary kwargs passed to jinja2 template.
+ Render the ``Styler`` including all applied styles to HTML.
+
+ Parameters
+ ----------
+ **kwargs
+ Any additional keyword arguments are passed
+ through to ``self.template.render``.
+ This is useful when you need to provide
+ additional variables for a custom template.
+
+ Returns
+ -------
+ rendered : str
+ The rendered HTML.
+
+ Notes
+ -----
+ Styler objects have defined the ``_repr_html_`` method
+ which automatically calls ``self.render()`` when it's the
+ last item in a Notebook cell. When calling ``Styler.render()``
+ directly, wrap the result in ``IPython.display.HTML`` to view
+ the rendered HTML in the notebook.
+
+ Pandas uses the following keys in render. Arguments passed
+ in ``**kwargs`` take precedence, so think carefully if you want
+ to override them:
+
+ * head
+ * cellstyle
+ * body
+ * uuid
+ * table_styles
+ * caption
+ * table_attributes
  """
  self._compute()
  # TODO: namespace all the pandas keys
@@ -486,8 +512,13 @@ def format(
  formatter = {col: formatter for col in columns}
 
  for col in columns:
+ try:
+ format_func = formatter[col]
+ except KeyError:
+ format_func = None
+
  format_func = _maybe_wrap_formatter(
- formatter.get(col),
+ format_func,
  na_rep=na_rep,
  precision=precision,
  decimal=decimal,
@@ -584,9 +615,15 @@ def _format_table_styles(styles: CSSStyles) -> CSSStyles:
  {'selector': 'th', 'props': 'a:v;'}]
  """
  return [
- {"selector": selector, "props": css_dict["props"]}
- for css_dict in styles
- for selector in css_dict["selector"].split(",")
+ item
+ for sublist in [
+ [ # this is a CSSDict when TypedDict is available to avoid cast.
+ {"selector": x, "props": style["props"]}
+ for x in cast(str, style["selector"]).split(",")
+ ]
+ for style in styles
+ ]
+ for item in sublist
  ]