Make an empty path_effect path for an empty string

Author: has2k1

lib/matplotlib/patheffects.py

@@ -138,9 +138,6 @@ def draw_path_collection(self, gc, master_transform, paths, *args,
                                           *args, **kwargs)
 
     def _draw_text_as_path(self, gc, x, y, s, prop, angle, ismath):
-        if not s.strip():
-            return
-
         # Implements the naive text drawing as is found in RendererBase.
         path, transform = self._get_text_path_transform(x, y, s, prop,
                                                         angle, ismath)

lib/matplotlib/textpath.py

@@ -129,6 +129,11 @@ def get_text_path(self, prop, s, ismath=False):
             verts.extend(verts1)
             codes.extend(codes1)
 
+        # Make sure an empty string or one with nothing to print
+        # (e.g. only spaces & newlines) will be valid/empty path
+        if not verts:
+            verts = np.empty((0, 2))
+
         return verts, codes
 
     def get_glyphs_with_font(self, font, s, glyph_map=None,