Cairo backend: Fix incorrect linestyle in draw_path_collection

joh · joh · commit 009d952b35dc · 2018-11-09T14:50:47.000+01:00
diff --git a/lib/matplotlib/backends/backend_cairo.py b/lib/matplotlib/backends/backend_cairo.py
@@ -306,10 +306,13 @@ def _draw_paths():
             for k, v in gc_vars.items():
                 if k == "_linestyle":  # Deprecated, no effect.
                     continue
-                try:
-                    getattr(gc, "set" + k)(v)
-                except (AttributeError, TypeError) as e:
-                    pass
+                elif k == "_dashes":
+                    gc.set_dashes(*v)  # Needs to be unpacked.
+                else:
+                    try:
+                        getattr(gc, "set" + k)(v)
+                    except (AttributeError, TypeError) as e:
+                        pass
             vars(gc).update(gc_vars)
             gc.ctx.new_path()
             paths, transforms = zip(*grouped_draw)
@@ -326,7 +329,8 @@ def _draw_paths():
             transform = (Affine2D(transform.get_matrix())
                          .translate(xo, yo - self.height).scale(1, -1))
             # rgb_fc could be a ndarray, for which equality is elementwise.
-            new_key = vars(gc0), tuple(rgb_fc) if rgb_fc is not None else None
+            new_key = (vars(gc0).copy(), tuple(rgb_fc) if rgb_fc is not None
+                       else None)
             # don't do grouped draw when doing alpha blending
             alpha_blending = gc0.get_forced_alpha() and gc0.get_alpha() < 1.0
             if not alpha_blending and rgb_fc is not None:
