ENH: rename switch_backend -> select_gui_toolkit

switch_backend is the Matplotlib name for this function, select_gui_toolkit is
clearer about what it is actually doing and why you would care!

Author: tacaswell

docs/source/api.rst

@@ -75,4 +75,4 @@ Select the backend
    :toctree: _as_gen
    :nosignatures:
 
-   mpl_gui.switch_backend
+   mpl_gui.select_gui_toolkit

mpl_gui/__init__.py

@@ -21,7 +21,7 @@
 from ._figure import Figure  # noqa: F401
 
 from ._manage_interactive import ion, ioff, is_interactive  # noqa: F401
-from ._manage_backend import switch_backend, current_backend_module as _cbm
+from ._manage_backend import select_gui_toolkit, current_backend_module as _cbm
 from ._promotion import promote_figure as promote_figure
 from ._creation import figure, subplots, subplot_mosaic  # noqa: F401
 
@@ -61,7 +61,7 @@ def show(figs, *, block=None, timeout=0):
     # TODO handle single figure
     if _cbm() is None:
         # set up the backend!
-        switch_backend()
+        select_gui_toolkit()
     managers = []
     for fig in figs:
         if fig.canvas.manager is not None:

mpl_gui/_manage_backend.py

@@ -17,11 +17,11 @@ def current_backend_module():
     return _backend_mod
 
 
-def switch_backend(newbackend=None):
+def select_gui_toolkit(newbackend=None):
     """
-    Close all open figures and set the Matplotlib backend.
+    Select the GUI toolkit to use.
 
-    The argument is case-insensitive.  Switching to an interactive backend is
+    The argument is case-insensitive.  Switching between GUI toolkits is
     possible only if no event loop for another interactive backend has started.
     Switching to and from non-interactive backends is always possible.
 
@@ -34,14 +34,13 @@ def switch_backend(newbackend=None):
     -------
     _Backend
        The backend selected.
+
     """
     global _backend_mod
 
     # work-around the sentinel resolution in Matplotlib 😱
     if newbackend is None:
         newbackend = dict.__getitem__(rcParams, "backend")
-    # make sure the init is pulled up so we can assign to it later
-    import matplotlib.backends
 
     if newbackend is rcsetup._auto_backend_sentinel:
         current_framework = cbook._get_running_interactive_framework()
@@ -67,14 +66,14 @@ def switch_backend(newbackend=None):
         # are of worse quality.
         for candidate in candidates:
             try:
-                return switch_backend(candidate)
+                return select_gui_toolkit(candidate)
             except ImportError:
                 continue
 
         else:
             # Switching to Agg should always succeed; if it doesn't, let the
             # exception propagate out.
-            return switch_backend("agg")
+            return select_gui_toolkit("agg")
 
     if isinstance(newbackend, str):
         # Backends are implemented as modules, but "inherit" default method

mpl_gui/tests/conftest.py

@@ -44,4 +44,4 @@ class TestingBackend(_Backend):
     Show = TestShow
 
 
-mpl_gui.switch_backend(TestingBackend)
+mpl_gui.select_gui_toolkit(TestingBackend)