OWConcurrentProjectionWidget: Add an example

Author: VesnaT

Orange/widgets/tests/base.py

@@ -857,10 +857,13 @@ def _compare_selected_annotated_domains(self, selected, annotated):
         annotated_vars = annotated.domain.variables
         self.assertLessEqual(set(selected_vars), set(annotated_vars))
 
-    def test_setup_graph(self):
+    def test_setup_graph(self, timeout=DEFAULT_TIMEOUT):
         """Plot should exist after data has been sent in order to be
         properly set/updated"""
         self.send_signal(self.widget.Inputs.data, self.data)
+        if self.widget.isBlocking():
+            spy = QSignalSpy(self.widget.blockingStateChanged)
+            self.assertTrue(spy.wait(timeout))
         self.assertIsNotNone(self.widget.graph.scatterplot_item)
 
     def test_default_attrs(self, timeout=DEFAULT_TIMEOUT):

Orange/widgets/utils/tests/concurrent_example.py

@@ -0,0 +1,137 @@
+# pylint: disable=too-many-ancestors
+from typing import Optional
+from types import SimpleNamespace as namespace
+
+import numpy as np
+
+from Orange.data import Table
+from Orange.widgets import gui
+from Orange.widgets.settings import Setting
+from Orange.widgets.utils.concurrent import TaskState, ConcurrentWidgetMixin
+from Orange.widgets.utils.widgetpreview import WidgetPreview
+from Orange.widgets.visualize.utils.widget import OWDataProjectionWidget
+
+
+class Result(namespace):
+    embedding = None  # type: Optional[np.ndarray]
+
+
+def run(data: Table, embedding: Optional[np.ndarray], state: TaskState):
+    res = Result(embedding=embedding)
+
+    # simulate wasteful calculation (increase 'steps')
+    step, steps = 0, 10
+    state.set_status("Calculating...")
+    while step < steps:
+        for _ in range(steps):
+            x_data = np.array(np.mean(data.X, axis=1))
+            if x_data.ndim == 2:
+                x_data = x_data.ravel()
+            y_data = np.random.rand(len(x_data))
+            # Needs a copy because projection should not be modified
+            # inplace. If it is modified inplace, the widget and the thread
+            #  hold a reference to the same object. When the thread is
+            # interrupted it is still modifying the object, but the widget
+            # receives it (the modified object) with a delay.
+            embedding = np.vstack((x_data, y_data)).T.copy()
+        step += 1
+        if step % (steps / 10) == 0:
+            state.set_progress_value(100 * step / steps)
+
+        if state.is_interruption_requested():
+            return res
+
+        res.embedding = embedding
+        state.set_partial_result(res)
+    return res
+
+
+class OWConcurrentWidget(OWDataProjectionWidget, ConcurrentWidgetMixin):
+    name = "Projection"
+    param = Setting(0)
+
+    def __init__(self):
+        OWDataProjectionWidget.__init__(self)
+        ConcurrentWidgetMixin.__init__(self)
+        self.embedding = None  # type: Optional[np.ndarray]
+
+    # GUI
+    def _add_controls(self):
+        box = gui.vBox(self.controlArea, True)
+        gui.comboBox(
+            box, self, "param", label="Parameter:",
+            items=["Param A", "Param B"], labelWidth=80,
+            callback=self.__param_combo_changed
+        )
+        self.run_button = gui.button(box, self, "Start", self._toggle_run)
+        super()._add_controls()
+
+    def __param_combo_changed(self):
+        self._run()
+
+    def _toggle_run(self):
+        if self.data is None:
+            return
+
+        # Pause task
+        if self.task is not None:
+            self.cancel()
+            self.run_button.setText("Resume")
+            self.commit()
+        # Resume task
+        else:
+            self._run()
+
+    def _run(self):
+        self.run_button.setText("Stop")
+        self.start(run, self.data, self.embedding)
+
+    # ConcurrentWidgetMixin
+    def on_partial_result(self, result: Result):
+        assert isinstance(result.embedding, np.ndarray)
+        assert len(result.embedding) == len(self.data)
+        first_result = self.embedding is None
+        self.embedding = result.embedding
+        if first_result:
+            self.setup_plot()
+        else:
+            self.graph.update_coordinates()
+            self.graph.update_density()
+
+    def on_done(self, result: Result):
+        # NOTE: All of these have already been set by on_partial_result,
+        # we double check that they are aliased
+        assert isinstance(result.embedding, np.ndarray)
+        assert len(result.embedding) == len(self.data)
+        self.embedding = result.embedding
+        self.run_button.setText("Start")
+        self.commit()
+
+    # OWDataProjectionWidget
+    def set_data(self, data: Table):
+        super().set_data(data)
+        if self._invalidated:
+            self._run()
+
+    def get_embedding(self):
+        if self.embedding is None:
+            self.valid_data = None
+            return None
+
+        self.valid_data = np.all(np.isfinite(self.embedding), 1)
+        return self.embedding
+
+    def clear(self):
+        super().clear()
+        self.cancel()
+        self.embedding = None
+
+    def onDeleteWidget(self):
+        self.shutdown()
+        super().onDeleteWidget()
+
+
+if __name__ == "__main__":
+    table = Table("iris")
+    WidgetPreview(OWConcurrentWidget).run(
+        set_data=table, set_subset_data=table[::10])

Orange/widgets/utils/tests/test_concurrent_example.py

@@ -0,0 +1,60 @@
+# Test methods with long descriptive names can omit docstrings
+# pylint: disable=missing-docstring
+import unittest
+from unittest.mock import Mock
+
+from Orange.data import Table
+from Orange.widgets.tests.base import (
+    WidgetTest, WidgetOutputsTestMixin, ProjectionWidgetTestMixin
+)
+from Orange.widgets.utils.tests.concurrent_example import (
+    OWConcurrentWidget
+)
+
+
+class TestOWConcurrentWidget(WidgetTest, ProjectionWidgetTestMixin,
+                             WidgetOutputsTestMixin):
+    @classmethod
+    def setUpClass(cls):
+        super().setUpClass()
+        WidgetOutputsTestMixin.init(cls)
+
+        cls.signal_name = "Data"
+        cls.signal_data = cls.data
+        cls.same_input_output_domain = False
+
+    def setUp(self):
+        self.widget = self.create_widget(OWConcurrentWidget)
+
+    def test_button_no_data(self):
+        self.widget.run_button.click()
+        self.assertEqual(self.widget.run_button.text(), "Start")
+
+    def test_button_with_data(self):
+        self.send_signal(self.widget.Inputs.data, self.data)
+        self.assertEqual(self.widget.run_button.text(), "Stop")
+        self.wait_until_stop_blocking()
+        self.assertEqual(self.widget.run_button.text(), "Start")
+
+    def test_button_toggle(self):
+        self.send_signal(self.widget.Inputs.data, self.data)
+        self.widget.run_button.click()
+        self.assertEqual(self.widget.run_button.text(), "Resume")
+
+    def test_plot_once(self):
+        table = Table("heart_disease")
+        self.widget.setup_plot = Mock()
+        self.widget.commit = Mock()
+        self.send_signal(self.widget.Inputs.data, table)
+        self.widget.setup_plot.assert_called_once()
+        self.widget.commit.assert_called_once()
+        self.wait_until_stop_blocking()
+        self.widget.setup_plot.reset_mock()
+        self.widget.commit.reset_mock()
+        self.send_signal(self.widget.Inputs.data_subset, table[::10])
+        self.widget.setup_plot.assert_not_called()
+        self.widget.commit.assert_called_once()
+
+
+if __name__ == "__main__":
+    unittest.main()