[FIX] WidgetSignalsMixin: Fix input/output ordering for 'newstyle' signals

Orange/widgets/utils/signals.py

@@ -1,7 +1,13 @@
 import copy
+import itertools
 
 from Orange.canvas.registry.description import InputSignal, OutputSignal
 
+# increasing counter for ensuring the order of Input/Output definitions
+# is preserved when going through the unordered class namespace of
+# WidgetSignalsMixin.Inputs/Outputs.
+_counter = itertools.count()
+
 
 class _Signal:
     @staticmethod
@@ -61,6 +67,7 @@ def __init__(self, name, type, id=None, doc=None, replaces=None, *,
                  multiple=False, default=False, explicit=False):
         flags = self.get_flags(multiple, default, explicit, False)
         super().__init__(name, type, "", flags, id, doc, replaces or [])
+        self._seq_id = next(_counter)
 
     def __call__(self, method):
         """
@@ -118,6 +125,7 @@ def __init__(self, name, type, id=None, doc=None, replaces=None, *,
         flags = self.get_flags(False, default, explicit, dynamic)
         super().__init__(name, type, flags, id, doc, replaces or [])
         self.widget = None
+        self._seq_id = next(_counter)
 
     def bound_signal(self, widget):
         """
@@ -234,8 +242,9 @@ def get_signals(cls, direction):
             return old_style
 
         signal_class = getattr(cls, direction.title())
-        return [signal for signal in signal_class.__dict__.values()
-                if isinstance(signal, _Signal)]
+        signals = [signal for signal in signal_class.__dict__.values()
+                   if isinstance(signal, _Signal)]
+        return list(sorted(signals, key=lambda s: s._seq_id))
 
 
 class AttributeList(list):

Orange/widgets/utils/tests/test_signals.py

@@ -12,7 +12,8 @@
     Single, Multiple, Default, NonDefault, Explicit, Dynamic, InputSignal, \
     OutputSignal
 from Orange.widgets.tests.base import GuiTest
-from Orange.widgets.utils.signals import _Signal, Input, Output
+from Orange.widgets.utils.signals import _Signal, Input, Output, \
+    WidgetSignalsMixin
 from Orange.widgets.widget import OWWidget
 
 
@@ -186,6 +187,26 @@ def foo(self):
         self.assertIsInstance(output, OutputSignal)
         self.assertEqual(output.name, "another name")
 
+    def test_get_signals_order(self):
+        class TestWidget(WidgetSignalsMixin):
+            class Inputs:
+                input_1 = Input("1", int)
+                input_2 = Input("2", int)
+                input_3 = Input("3", int)
+                input_a = Input("a", object)
+
+            class Outputs:
+                output_1 = Output("1", int)
+                output_2 = Output("2", int)
+                output_3 = Output("3", int)
+                output_a = Output("a", object)
+
+        inputs = TestWidget.get_signals("inputs")
+        self.assertTrue(all(isinstance(s, Input) for s in inputs))
+        self.assertSequenceEqual([s.name for s in inputs], list("123a"))
+        outputs = TestWidget.get_signals("outputs")
+        self.assertTrue(all(isinstance(s, Output) for s in outputs))
+        self.assertSequenceEqual([s.name for s in outputs], list("123a"))
 
 if __name__ == "__main__":
     unittest.main()