ENH: Styler css Str optional input arguments as well as List[Tuple]

doc/source/user_guide/style.ipynb

@@ -180,8 +180,7 @@
  "\n",
  "styles = [\n",
  " hover(),\n",
- " {'selector': \"th\", 'props': [(\"font-size\", \"150%\"),\n",
- " (\"text-align\", \"center\")]}\n",
+ " {'selector': \"th\", 'props': [(\"font-size\", \"150%\"), (\"text-align\", \"center\")]}\n",
  "]\n",
  "\n",
  "df.style.set_table_styles(styles)"
@@ -224,7 +223,7 @@
  "cell_type": "markdown",
  "metadata": {},
  "source": [
- "We can also chain all of the above by setting the `overwrite` argument to `False` so that it preserves previous settings."
+ "We can also chain all of the above by setting the `overwrite` argument to `False` so that it preserves previous settings. We also show the CSS string input rather than the list of tuples."
  ]
  },
  {
@@ -238,13 +237,13 @@
  " set_table_styles(styles).\\\n",
  " set_table_styles({\n",
  " 'A': [{'selector': '',\n",
- " 'props': [('color', 'red')]}],\n",
+ " 'props': 'color:red;'}],\n",
  " 'B': [{'selector': 'td',\n",
- " 'props': [('color', 'blue')]}]\n",
+ " 'props': 'color:blue;'}]\n",
  " }, axis=0, overwrite=False).\\\n",
  " set_table_styles({\n",
  " 3: [{'selector': 'td',\n",
- " 'props': [('color', 'green')]}]\n",
+ " 'props': 'color:green;font-weight:bold;'}]\n",
  " }, axis=1, overwrite=False)\n",
  "s"
  ]

doc/source/whatsnew/v1.3.0.rst

@@ -56,6 +56,7 @@ Other enhancements
 - :meth:`.Styler.set_tooltips` allows on hover tooltips to be added to styled HTML dataframes.
 - :meth:`Series.loc.__getitem__` and :meth:`Series.loc.__setitem__` with :class:`MultiIndex` now raising helpful error message when indexer has too many dimensions (:issue:`35349`)
 - :meth:`pandas.read_stata` and :class:`StataReader` support reading data from compressed files.
+- :meth:`.Styler.set_tooltips_class` and :meth:`.Styler.set_table_styles` amended to optionally allow certain css-string input arguments.
 
 .. ---------------------------------------------------------------------------
 

pandas/io/formats/style.py

@@ -279,8 +279,8 @@ def set_tooltips_class(
  ----------
  name : str, default None
  Name of the tooltip class used in CSS, should conform to HTML standards.
- properties : list-like, default None
- List of (attr, value) tuples; see example.
+ properties : list-like or str, default None
+ List of (attr, value) tuples or a valid CSS string; see example.
 
  Returns
  -------
@@ -311,6 +311,8 @@ def set_tooltips_class(
  ... ('visibility', 'hidden'),
  ... ('position', 'absolute'),
  ... ('z-index', 1)])
+ >>> df.style.set_tooltips_class(name='tt-add',
+ ... properties='visibility:hidden; position:absolute; z-index:1;')
  """
  self._init_tooltips()
  assert self.tooltips is not None # mypy requirement
@@ -1172,13 +1174,20 @@ def set_table_styles(self, table_styles, axis=0, overwrite=True) -> Styler:
  ... 'props': [('background-color', 'yellow')]}]
  ... )
 
+ Or with CSS strings
+
+ >>> df.style.set_table_styles(
+ ... [{'selector': 'tr:hover',
+ ... 'props': 'background-color: yellow; font-size: 1em;']}]
+ ... )
+
  Adding column styling by name
 
  >>> df.style.set_table_styles({
  ... 'A': [{'selector': '',
  ... 'props': [('color', 'red')]}],
  ... 'B': [{'selector': 'td',
- ... 'props': [('color', 'blue')]}]
+ ... 'props': 'color: blue;']}]
  ... }, overwrite=False)
 
  Adding row styling
@@ -1203,6 +1212,14 @@ def set_table_styles(self, table_styles, axis=0, overwrite=True) -> Styler:
  for s in styles
  ]
 
+ table_styles = [
+ {
+ "selector": s["selector"],
+ "props": _maybe_convert_css_to_tuples(s["props"]),
+ }
+ for s in table_styles
+ ]
+
  if not overwrite and self.table_styles is not None:
  self.table_styles.extend(table_styles)
  else:
@@ -1843,7 +1860,12 @@ def _class_styles(self):
  -------
  styles : List
  """
- return [{"selector": f".{self.class_name}", "props": self.class_properties}]
+ return [
+ {
+ "selector": f".{self.class_name}",
+ "props": _maybe_convert_css_to_tuples(self.class_properties),
+ }
+ ]
 
  def _pseudo_css(self, uuid: str, name: str, row: int, col: int, text: str):
  """
@@ -2025,3 +2047,28 @@ def _maybe_wrap_formatter(
  else:
  msg = f"Expected a string, got {na_rep} instead"
  raise TypeError(msg)
+
+
+def _maybe_convert_css_to_tuples(
+ style: Union[str, Sequence[Tuple[str, Union[str, int, float]]]]
+):
+ """
+ Convert css-string to sequence of tuples format if needed.
+ 'color:red; border:1px solid black;' -> [('color', 'red'),
+ ('border','1px solid red')]
+ """
+ if isinstance(style, str):
+ s = style.split(";")
+ try:
+ ret = [
+ (x.split(":")[0].strip(), x.split(":")[1].strip())
+ for x in s
+ if x.strip() != ""
+ ]
+ return ret
+ except IndexError:
+ raise ValueError(
+ "Styles supplied as string must follow CSS rule formats, "
+ f"for example 'attr: val;'. {style} was given."
+ )
+ return style

pandas/tests/io/formats/test_style.py

@@ -12,7 +12,11 @@
 import pandas._testing as tm
 
 jinja2 = pytest.importorskip("jinja2")
-from pandas.io.formats.style import Styler, _get_level_lengths # isort:skip
+from pandas.io.formats.style import ( # isort:skip
+ Styler,
+ _get_level_lengths,
+ _maybe_convert_css_to_tuples,
+)
 
 
 class TestStyler:
@@ -1167,7 +1171,7 @@ def test_unique_id(self):
  assert np.unique(ids).size == len(ids)
 
  def test_table_styles(self):
- style = [{"selector": "th", "props": [("foo", "bar")]}]
+ style = [{"selector": "th", "props": [("foo", "bar")]}] # default format
  styler = Styler(self.df, table_styles=style)
  result = " ".join(styler.render().split())
  assert "th { foo: bar; }" in result
@@ -1177,6 +1181,24 @@ def test_table_styles(self):
  assert styler is result
  assert styler.table_styles == style
 
+ # GH 39563
+ style = [{"selector": "th", "props": "foo:bar;"}] # css string format
+ styler = self.df.style.set_table_styles(style)
+ result = " ".join(styler.render().split())
+ assert "th { foo: bar; }" in result
+
+ def test_maybe_convert_css_to_tuples(self):
+ expected = [("a", "b"), ("c", "d e")]
+ assert _maybe_convert_css_to_tuples("a:b;c:d e;") == expected
+ assert _maybe_convert_css_to_tuples("a: b ;c: d e ") == expected
+ expected = []
+ assert _maybe_convert_css_to_tuples("") == expected
+
+ def test_maybe_convert_css_to_tuples_err(self):
+ msg = "Styles supplied as string must follow CSS rule formats"
+ with pytest.raises(ValueError, match=msg):
+ _maybe_convert_css_to_tuples("err")
+
  def test_table_attributes(self):
  attributes = 'class="foo" data-bar'
  styler = Styler(self.df, table_attributes=attributes)
@@ -1897,6 +1919,18 @@ def test_tooltip_class(self):
  in s
  )
 
+ # GH 39563
+ s = (
+ Styler(df, uuid_len=0)
+ .set_tooltips(DataFrame([["tooltip"]]))
+ .set_tooltips_class(name="other-class", properties="color:green;color:red;")
+ .render()
+ )
+ assert (
+ "#T__ .other-class {\n color: green;\n color: red;\n "
+ in s
+ )
+
 
 @td.skip_if_no_mpl
 class TestStylerMatplotlibDep: