Backport PR #25496: BUG: fix IPython's %pylab mode detection

tacaswell · meeseeksmachine · commit fb8d77353e27 · 2023-03-20T14:05:52.000Z
diff --git a/lib/matplotlib/backend_bases.py b/lib/matplotlib/backend_bases.py
@@ -2898,8 +2898,8 @@ def pyplot_show(cls, *, block=None):
             # Hack: Are we in IPython's %pylab mode?  In pylab mode, IPython
             # (>= 0.10) tacks a _needmain attribute onto pyplot.show (always
             # set to False).
-            ipython_pylab = hasattr(
-                getattr(sys.modules.get("pyplot"), "show", None), "_needmain")
+            pyplot_show = getattr(sys.modules.get("matplotlib.pyplot"), "show", None)
+            ipython_pylab = hasattr(pyplot_show, "_needmain")
             block = not ipython_pylab and not is_interactive()
         if block:
             cls.start_main_loop()
@@ -3613,8 +3613,8 @@ def show(cls, *, block=None):
             # Hack: Are we in IPython's %pylab mode?  In pylab mode, IPython
             # (>= 0.10) tacks a _needmain attribute onto pyplot.show (always
             # set to False).
-            ipython_pylab = hasattr(
-                getattr(sys.modules.get("pyplot"), "show", None), "_needmain")
+            pyplot_show = getattr(sys.modules.get("matplotlib.pyplot"), "show", None)
+            ipython_pylab = hasattr(pyplot_show, "_needmain")
             block = not ipython_pylab and not is_interactive()
         if block:
             cls.mainloop()
