MNT: theory 1

tacaswell · tacaswell · commit b9051587a376 · 2024-09-17T09:22:10.000-04:00
diff --git a/lib/matplotlib/text.py b/lib/matplotlib/text.py
@@ -66,15 +66,26 @@ def _get_text_metrics_with_cache(renderer, text, fontprop, ismath, dpi):
     """Call ``renderer.get_text_width_height_descent``, caching the results."""
     # Cached based on a copy of fontprop so that later in-place mutations of
     # the passed-in argument do not mess up the cache.
-    return _get_text_metrics_with_cache_impl(
-        weakref.ref(renderer), text, fontprop.copy(), ismath, dpi)
+    func = _get_text_metrics_function(weakref.ref(renderer))
+    return func(text, fontprop.copy(), ismath, dpi)
 
 
-@functools.lru_cache(4096)
-def _get_text_metrics_with_cache_impl(
-        renderer_ref, text, fontprop, ismath, dpi):
-    # dpi is unused, but participates in cache invalidation (via the renderer).
-    return renderer_ref().get_text_width_height_descent(text, fontprop, ismath)
+@functools.lru_cache(25)
+def _get_text_metrics_function(renderer_ref):
+
+    @functools.lru_cache(4096)
+    def _text_metrics(text, fontprop, ismath, dpi):
+        # dpi is unused, but participates in cache invalidation (via the renderer).
+        renderer = renderer_ref()
+        if renderer is None:
+            raise RuntimeError(
+                "You are trying to get the font metrics for a renderer that no "
+                "longer exists.  There is likely a deeper bug someplace else "
+                "as this should never happen."
+            )
+        return renderer.get_text_width_height_descent(text, fontprop, ismath)
+
+    return _text_metrics
 
 
 @_docstring.interpd
