Permit overriding obj._guide_kw kwargs (fix #314)

Author: lukelbd

proplot/figure.py

@@ -1640,10 +1640,10 @@ def colorbar(
         # Fill this axes
         if cax is not None:
             with context._state_context(cax, _internal_call=True):  # do not wrap pcolor
-                return super().colorbar(mappable, cax=cax, **kwargs)
+                cb = super().colorbar(mappable, cax=cax, **kwargs)
         # Axes panel colorbar
         elif ax is not None:
-            return ax.colorbar(
+            cb = ax.colorbar(
                 mappable, values, space=space, pad=pad, width=width, **kwargs
             )
         # Figure panel colorbar
@@ -1653,7 +1653,8 @@ def colorbar(
                 loc, row=row, col=col, rows=rows, cols=cols, span=span,
                 width=width, space=space, pad=pad,
             )
-            return ax.colorbar(mappable, values, loc='fill', **kwargs)
+            cb = ax.colorbar(mappable, values, loc='fill', **kwargs)
+        return cb
 
     @docstring._concatenate_inherited
     @docstring._snippet_manager
@@ -1686,7 +1687,7 @@ def legend(
         ax = kwargs.pop('ax', None)
         # Axes panel legend
         if ax is not None:
-            return ax.legend(
+            leg = ax.legend(
                 handles, labels, space=space, pad=pad, width=width, **kwargs
             )
         # Figure panel legend
@@ -1696,7 +1697,8 @@ def legend(
                 loc, row=row, col=col, rows=rows, cols=cols, span=span,
                 width=width, space=space, pad=pad,
             )
-            return ax.legend(handles, labels, loc='fill', **kwargs)
+            leg = ax.legend(handles, labels, loc='fill', **kwargs)
+        return leg
 
     @docstring._snippet_manager
     def save(self, filename, **kwargs):

proplot/internals/guides.py

@@ -12,7 +12,7 @@
 from . import warnings
 
 
-def _fill_guide_kw(kwargs, **pairs):
+def _fill_guide_kw(kwargs, overwrite=False, **pairs):
     """
     Add the keyword arguments to the dictionary if not already present.
     """
@@ -26,16 +26,21 @@ def _fill_guide_kw(kwargs, **pairs):
             continue
         keys = tuple(a for group in aliases for a in group if key in group)  # may be ()
         if not any(kwargs.get(key) is not None for key in keys):  # note any(()) is True
-            kwargs[key] = value
+            if overwrite:
+                kwargs[key] = value
+            else:
+                kwargs.setdefault(key, value)
 
 
 def _guide_kw_from_obj(obj, name, kwargs):
     """
     Add to the dict from settings stored on the object if there are no conflicts.
     """
+    # WARNING: Here we *do not* want to overwrite properties in the dictionary.
+    # Indicates e.g. calling colorbar(extend='both') after pcolor(extend='neither').
     pairs = getattr(obj, f'_{name}_kw', None)
     pairs = pairs or {}  # needed for some reason
-    _fill_guide_kw(kwargs, **pairs)
+    _fill_guide_kw(kwargs, overwrite=False, **pairs)
     if isinstance(obj, (tuple, list, np.ndarray)):
         for iobj in obj:  # possibly iterate over matplotlib tuple/list subclasses
             _guide_kw_from_obj(iobj, name, kwargs)
@@ -59,8 +64,10 @@ def _guide_kw_to_arg(name, kwargs, **pairs):
     """
     Add to the `colorbar_kw` or `legend_kw` dict if there are no conflicts.
     """
+    # WARNING: Here we *do* want to overwrite properties in dictionary. Indicates
+    # updating kwargs during parsing (probably only relevant for ax.parametric).
     kw = kwargs.setdefault(f'{name}_kw', {})
-    _fill_guide_kw(kw, **pairs)
+    _fill_guide_kw(kw, overwrite=True, **pairs)
 
 
 def _iter_children(*args):