colorbar defaults to stealing space from the mappable's axes rather than the current axes

Pass ``ax=plt.gca()`` to restore the previous behavior.

If the mappable does not have an Axes, then an error will be raised.

Pass the *cax* or *ax* argument to be explicit about where the colorbar will be

placed. Passing ``ax=plt.gca()`` will restore the previous behavior.

Removal of deprecated ``colorbar`` APIs

ifaxisNone:

ax=getattr(mappable,"axes",self.gca())

ax=getattr(mappable,"axes",None)

if (self.get_layout_engine()isnotNoneand

notself.get_layout_engine().colorbar_gridspec):

ifcaxisNone:

ifaxisNone:

raiseValueError(

'from it, or add *mappable* to an Axes.')

current_ax=self.gca()

if (use_gridspecandisinstance(ax,SubplotBase)):

Colorbar(ax,cmap=plt.cm.bone)

deftest_parentless_mappable():

pc=mpl.collections.PatchCollection([],cmap=plt.get_cmap('viridis'))

pc.set_array([])

withpytest.raises(ValueError,match='Unable to determine Axes to steal'):

plt.colorbar(pc)

deftest_colorbar_closed_patch():

deftest_mappable_no_alpha():

fig,ax=plt.subplots()

sm=cm.ScalarMappable(norm=mcolors.Normalize(),cmap='viridis')

fig.colorbar(sm)

fig.colorbar(sm,ax=ax)

sm.set_cmap('plasma')

plt.draw()