Adds ability to override specific style kwargs while also using an au…

…tomatic style

src/earthkit/plots/components/subplots.py

@@ -28,7 +28,7 @@
 )
 from earthkit.plots.schemas import schema
 from earthkit.plots.sources import get_source, single
-from earthkit.plots.styles import _STYLE_KWARGS, Contour, Style, auto
+from earthkit.plots.styles import _OVERRIDE_KWARGS, _STYLE_KWARGS, Contour, Style, auto
 from earthkit.plots.utils import iter_utils, string_utils
 
 DEFAULT_FORMATS = ["%Y", "%b", "%-d", "%H:%M", "%H:%M", "%S.%f"]
@@ -323,13 +323,17 @@ def _extract_plottables(
             style_kwargs = {
                 key: kwargs.pop(key) for key in _STYLE_KWARGS if key in kwargs
             }
+            # These are kwargs which can be overridden without forcing a new Style
+            override_kwargs = {key: style_kwargs.pop(key) for key in _OVERRIDE_KWARGS}
             if style_kwargs:
                 style_class = (
                     Style if not method_name.startswith("contour") else Contour
                 )
                 style = style_class(**{**style_kwargs, **{"units": units}})
             else:
-                style = auto.guess_style(source, units=units or source.units)
+                style = auto.guess_style(
+                    source, units=units or source.units, **override_kwargs
+                )
         if (data is None and z is None) or (z is not None and not z):
             z_values = None
         else:

src/earthkit/plots/styles/__init__.py

@@ -32,6 +32,7 @@
     "Style",
     "DEFAULT_STYLE",
     "_STYLE_KWARGS",
+    "_OVERRIDE_KWARGS",
 ]
 
 
@@ -791,7 +792,7 @@ class Contour(Style):
     def __init__(
         self,
         colors=None,
-        line_colors=None,
+        line_colors="#555",
         labels=False,
         label_kwargs=None,
         interpolate=True,
@@ -826,6 +827,7 @@ def to_contour_kwargs(self, data):
             The data to be plotted using this `Style`.
         """
         levels = self.levels(data)
+
         cmap, norm = styles.colors.cmap_and_norm(
             self._line_colors,
             levels,
@@ -1020,3 +1022,5 @@ def disjoint(self, layer, *args, **kwargs):
 _STYLE_KWARGS = list(
     set(inspect.getfullargspec(Style)[0] + inspect.getfullargspec(Contour)[0])
 )
+
+_OVERRIDE_KWARGS = ["labels"]

src/earthkit/plots/styles/auto.py

@@ -24,7 +24,7 @@
 from earthkit.plots.schemas import schema
 
 
-def guess_style(data, units=None):
+def guess_style(data, units=None, **kwargs):
     """
     Guess the style to be applied to the data based on its metadata.
 
@@ -97,4 +97,4 @@ def guess_style(data, units=None):
             # No style matching units found; return default
             return styles.DEFAULT_STYLE
 
-    return styles.Style.from_dict(style)
+    return styles.Style.from_dict({**style, **kwargs})