Make sure SubFigure have _cachedRenderer

oscargus · oscargus · commit 02fde4225e23 · 2022-06-01T12:30:25.000+02:00
diff --git a/lib/matplotlib/figure.py b/lib/matplotlib/figure.py
@@ -188,6 +188,7 @@ def __init__(self, **kwargs):
         self.subfigs = []
         self.stale = True
         self.suppressComposite = None
+        self._cachedRenderer = None
         self.set(**kwargs)
 
     def _get_draw_artists(self, renderer):
@@ -2360,7 +2361,6 @@ def __init__(self,
 
         self._axstack = _AxesStack()  # track all figure axes and current axes
         self.clear()
-        self._cachedRenderer = None
 
         # list of child gridspecs for this figure
         self._gridspecs = []
diff --git a/lib/matplotlib/tests/test_contour.py b/lib/matplotlib/tests/test_contour.py
@@ -585,3 +585,23 @@ def test_all_algorithms():
         ax.contourf(x, y, z, algorithm=algorithm)
         ax.contour(x, y, z, algorithm=algorithm, colors='k')
         ax.set_title(algorithm)
+
+
+def test_subfigure_clabel():
+    # Smoke test for gh#23173
+    delta = 0.025
+    x = np.arange(-3.0, 3.0, delta)
+    y = np.arange(-2.0, 2.0, delta)
+    X, Y = np.meshgrid(x, y)
+    Z1 = np.exp(-(X**2) - Y**2)
+    Z2 = np.exp(-((X - 1) ** 2) - (Y - 1) ** 2)
+    Z = (Z1 - Z2) * 2
+
+    fig = plt.figure()
+    figs = fig.subfigures(nrows=1, ncols=2)
+
+    for f in figs:
+        ax = f.subplots()
+        CS = ax.contour(X, Y, Z)
+        ax.clabel(CS, inline=True, fontsize=10)
+        ax.set_title("Simplest default with labels")
