Merge pull request #12143 from meeseeksmachine/auto-backport-of-pr-12142-on-v3.0.x

tacaswell · web-flow · commit 5074303e7797 · 2018-09-17T14:18:57.000-04:00
Backport PR #12142 on branch v3.0.x (Unbreak formlayout for image edits.)
diff --git a/lib/matplotlib/backends/qt_editor/formlayout.py b/lib/matplotlib/backends/qt_editor/formlayout.py
@@ -243,8 +243,14 @@ def setup(self):
             elif isinstance(value, str):
                 field = QtWidgets.QLineEdit(value, self)
             elif isinstance(value, (list, tuple)):
+                if isinstance(value, tuple):
+                    value = list(value)
+                # Note: get() below checks the type of value[0] in self.data so
+                # it is essential that value gets modified in-place.
+                # This means that the code is actually broken in the case where
+                # value is a tuple, but fortunately we always pass a list...
+                selindex = value.pop(0)
                 field = QtWidgets.QComboBox(self)
-                selindex, *value = value
                 if isinstance(value[0], (list, tuple)):
                     keys = [key for key, _val in value]
                     value = [val for _key, val in value]
