Add automated input summaries

orangewidget/utils/signals.py

@@ -84,21 +84,34 @@ def set_train_data(self, data):
         explicitly connected in the dialog (default: `False`)
     """
     def __init__(self, name, type, id=None, doc=None, replaces=None, *,
-                 multiple=False, default=False, explicit=False):
+                 multiple=False, default=False, explicit=False,
+                 auto_summary=None):
         flags = self.get_flags(multiple, default, explicit, False)
         super().__init__(name, type, "", flags, id, doc, replaces or [])
+        self.auto_summary = auto_summary
         self._seq_id = next(_counter)
 
     def __call__(self, method):
         """
         Decorator that stores decorated method's name in the signal's
         `handler` attribute. The method is returned unchanged.
         """
+        def set_summary(widget, value, *args, **kwargs):
+            if self.auto_summary:
+                info = widget.info
+                if value is None:
+                    info.set_input_summary(info.NoInput)
+                else:
+                    summary, details = summarize(value)
+                    if summary is not None:
+                        info.set_input_summary(summary, details)
+            return method(widget, value, *args, **kwargs)
+
         if self.handler:
             raise ValueError("Input {} is already bound to method {}".
                              format(self.name, self.handler))
         self.handler = method.__name__
-        return method
+        return set_summary
 
 
 class Output(OutputSignal, _Signal):
@@ -285,13 +298,15 @@ def set_default_auto_summary(cls):
         set that signal's auto_summary to True, so that it's value will be
         shown in the status.
         """
-        outputs = getmembers(cls.Outputs, Output)
-        if any(output.auto_summary for _, output in outputs):
-            return
-        for _, output in outputs:
-            if output.auto_summary is None:
-                output.auto_summary = \
-                    bool(output.flags & Default) or len(outputs) == 1
+        for signal_cls, signal_type in ((cls.Inputs, Input),
+                                        (cls.Outputs, Output)):
+            signals = getmembers(signal_cls, signal_type)
+            if any(signal.auto_summary for _, signal in signals):
+                continue
+            for _, signal in signals:
+                if signal.auto_summary is None:
+                    signal.auto_summary = \
+                        bool(signal.flags & Default) or len(signals) == 1
 
 
 class AttributeList(list):