LDAVis - Fix fail after None data

orangecontrib/text/widgets/owldavis.py

@@ -1,4 +1,4 @@
-from typing import Dict, List, Optional, Tuple
+from typing import Dict, List, Optional, Tuple, Set
 
 import numpy as np
 import pyqtgraph as pg
@@ -230,9 +230,9 @@ class OWLDAvis(OWWidget):
     icon = "icons/LDAvis.svg"
     keywords = "ldavis"
 
-    selected_topic = Setting(0, schema_only=True)
-    relevance = Setting(0.5)
-    visual_settings = Setting({}, schema_only=True)
+    selected_topic: int = Setting(0, schema_only=True)
+    relevance: float = Setting(0.5)
+    visual_settings: Set = Setting({}, schema_only=True)
 
     graph = SettingProvider(BarPlotGraph)
     graph_name = "graph.plotItem"
@@ -329,7 +329,6 @@ def on_params_change(self):
 
     @Inputs.topics
     def set_data(self, data: Optional[Topics]):
-        prev_topic = self.selected_topic
         self.clear()
         if data is None:
             return
@@ -343,7 +342,8 @@ def set_data(self, data: Optional[Topics]):
         self.term_topic_matrix = self.compute_distributions(data)
         self.term_frequency = np.sum(self.term_topic_matrix, axis=0)
 
-        self.selected_topic = prev_topic if prev_topic < len(self.topic_list) else 0
+        st = self.selected_topic
+        self.selected_topic = st if st < len(self.topic_list) else 0
         self.on_params_change()
 
     def set_visual_settings(self, key: KeyType, value: ValueType):
@@ -354,7 +354,10 @@ def clear(self):
         self.Error.clear()
         self.graph.clear_all()
         self.data = None
+        prev_topic = self.selected_topic
         self.topic_list = []
+        # resting topic_list resets selected_topic to None - setting back to prev value
+        self.selected_topic = prev_topic
         self.term_topic_matrix = None
         self.term_frequency = None
         self.num_tokens = None

orangecontrib/text/widgets/tests/test_owldavis.py

@@ -113,6 +113,33 @@ def test_report(self, mocked_plot, mocked_items: Mock):
         mocked_items.assert_called_once()
         mocked_plot. assert_called_once()
 
+    def test_wrong_model(self):
+        lsi_topic = self.topics.copy()
+        lsi_topic.attributes["Model"] = "Latent Sematic Indexing"
+        self.send_signal(self.widget.Inputs.topics, lsi_topic)
+        self.assertTrue(self.widget.Error.wrong_model.is_shown())
+
+        self.send_signal(self.widget.Inputs.topics, self.topics)
+        self.assertFalse(self.widget.Error.wrong_model.is_shown())
+        self.assertListEqual(
+            ["Topic 1", "Topic 2", "Topic 3", "Topic 4", "Topic 5"],
+            self.widget.topic_list,
+        )
+        self.widget.topic_box.setCurrentRow(2)
+        self.assertEqual(2, self.widget.selected_topic)
+
+        self.send_signal(self.widget.Inputs.topics, lsi_topic)
+        self.assertTrue(self.widget.Error.wrong_model.is_shown())
+
+        self.send_signal(self.widget.Inputs.topics, self.topics)
+        self.assertFalse(self.widget.Error.wrong_model.is_shown())
+        self.assertListEqual(
+            ["Topic 1", "Topic 2", "Topic 3", "Topic 4", "Topic 5"],
+            self.widget.topic_list,
+        )
+        # should be remembered from before
+        self.assertEqual(2, self.widget.selected_topic)
+
 
 if __name__ == "__main__":
     unittest.main()