DEPR: null_color since color used everywhere else

doc/source/user_guide/style.ipynb

@@ -1131,7 +1131,7 @@
    "source": [
     "df2.iloc[0,2] = np.nan\n",
     "df2.iloc[4,3] = np.nan\n",
-    "df2.loc[:4].style.highlight_null(null_color='yellow')"
+    "df2.loc[:4].style.highlight_null(color='yellow')"
    ]
   },
   {

pandas/io/formats/style.py

@@ -3097,19 +3097,23 @@ def bar(
 
         return self
 
-    @Substitution(subset=subset, props=props)
+    @Substitution(subset=subset, props=props, color=color)
     def highlight_null(
         self,
-        null_color: str = "red",
+        color: str | None = None,
         subset: Subset | None = None,
         props: str | None = None,
+        null_color: str | None = "red",
     ) -> Styler:
         """
         Highlight missing values with a style.
 
         Parameters
         ----------
-        null_color : str, default 'red'
+        %(color)s
+
+            .. versionadded:: 1.5.0
+
         %(subset)s
 
             .. versionadded:: 1.1.0
@@ -3118,6 +3122,13 @@ def highlight_null(
 
             .. versionadded:: 1.3.0
 
+        null_color : str, default 'red'
+            The background color for highlighting.
+
+            .. deprecated:: 1.5.0
+               Use ``color`` instead. If ``color`` is given ``null_color`` is
+               not used.
+
         Returns
         -------
         self : Styler
@@ -3133,8 +3144,12 @@ def highlight_null(
         def f(data: DataFrame, props: str) -> np.ndarray:
             return np.where(pd.isna(data).to_numpy(), props, "")
 
+        if null_color != "red":
+            raise FutureWarning("`null_color` is deprecated: use `color` instead")
+
+        color = color if color else null_color
         if props is None:
-            props = f"background-color: {null_color};"
+            props = f"background-color: {color};"
         return self.apply(f, axis=None, subset=subset, props=props)
 
     @Substitution(subset=subset, color=color, props=props)

pandas/tests/io/formats/style/test_highlight.py

@@ -37,8 +37,8 @@ def test_highlight_null(styler):
 def test_highlight_null_subset(styler):
     # GH 31345
     result = (
-        styler.highlight_null(null_color="red", subset=["A"])
-        .highlight_null(null_color="green", subset=["B"])
+        styler.highlight_null(color="red", subset=["A"])
+        .highlight_null(color="green", subset=["B"])
         ._compute()
         .ctx
     )