Raise an error in the pdf backend instead of outputting an invalid path if a Path object lacks initial moveto

jkseppan · jkseppan · commit 46e9f6f1c015 · 2009-10-21T18:41:35.000Z
svn path=/trunk/matplotlib/; revision=7899
diff --git a/lib/matplotlib/backends/backend_pdf.py b/lib/matplotlib/backends/backend_pdf.py
@@ -1206,8 +1206,12 @@ def pathOperations(path, transform, clip=None):
         last_points = None
         for points, code in path.iter_segments(transform, clip=clip):
             if code == Path.MOVETO:
+                # This is allowed anywhere in the path
                 cmds.extend(points)
                 cmds.append(Op.moveto)
+            elif last_points is None:
+                # The other operations require a previous point
+                raise ValueError, 'Path lacks initial MOVETO'
             elif code == Path.LINETO:
                 cmds.extend(points)
                 cmds.append(Op.lineto)
