[widgets][assetbrowser] Implement setCurrentAsset and currentAsset

These will allow for synchronisation between editor
and the browser.

This patch also regactors the code for testing purpose.

beat/editor/test/test_assetbrowser.py

+# vim: set fileencoding=utf-8 :
+###############################################################################
+#                                                                             #
+# Copyright (c) 2019 Idiap Research Institute, http://www.idiap.ch/           #
+# Contact: beat.support@idiap.ch                                              #
+#                                                                             #
+# This file is part of the beat.editor module of the BEAT platform.           #
+#                                                                             #
+# Commercial License Usage                                                    #
+# Licensees holding valid commercial BEAT licenses may use this file in       #
+# accordance with the terms contained in a written agreement between you      #
+# and Idiap. For further information contact tto@idiap.ch                     #
+#                                                                             #
+# Alternatively, this file may be used under the terms of the GNU Affero      #
+# Public License version 3 as published by the Free Software and appearing    #
+# in the file LICENSE.AGPL included in the packaging of this file.            #
+# The BEAT platform is distributed in the hope that it will be useful, but    #
+# WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY  #
+# or FITNESS FOR A PARTICULAR PURPOSE.                                        #
+#                                                                             #
+# You should have received a copy of the GNU Affero Public License along      #
+# with the BEAT platform. If not, see http://www.gnu.org/licenses/.           #
+#                                                                             #
+###############################################################################
+
+from PyQt5.QtCore import Qt
+
+from ..backend.asset import AssetType
+from ..backend.asset import Asset
+from ..widgets.assetbrowser import AssetBrowser
+
+
+class TestAssetBrowser:
+    def test_set_current_asset(self, qtbot, test_prefix, beat_context):
+        browser = AssetBrowser()
+        qtbot.addWidget(browser)
+        browser.set_context(beat_context)
+
+        asset = Asset(test_prefix, AssetType.ALGORITHM, "user/integers_add_v2/1")
+
+        with qtbot.waitSignal(browser.view.selectionModel().currentChanged):
+            browser.setCurrentAsset(asset)
+        assert browser.currentAsset() == asset
+
+    def test_double_click(self, qtbot, test_prefix, beat_context):
+        browser = AssetBrowser()
+        qtbot.addWidget(browser)
+        browser.set_context(beat_context)
+
+        asset = Asset(test_prefix, AssetType.ALGORITHM, "autonomous/add/1")
+        browser.setCurrentAsset(asset)
+        index = browser.view.currentIndex()
+        browser.view.scrollTo(index)
+        rect = browser.view.visualRect(index)
+        click_point = rect.center()
+
+        with qtbot.waitSignal(browser.view.clicked):
+            qtbot.mouseClick(browser.view.viewport(), Qt.LeftButton, pos=click_point)
+        with qtbot.waitSignal(browser.assetSelected):
+            qtbot.mouseDClick(browser.view.viewport(), Qt.LeftButton, pos=click_point)
+
+    def test_deletion_request(self, qtbot, test_prefix, beat_context):
+        browser = AssetBrowser()
+        qtbot.addWidget(browser)
+        browser.set_context(beat_context)
+
+        asset = Asset(test_prefix, AssetType.ALGORITHM, "autonomous/add/1")
+        browser.setCurrentAsset(asset)
+        index = browser.view.currentIndex()
+        browser.view.scrollTo(index)
+        rect = browser.view.visualRect(index)
+        click_point = rect.center()
+        right_click_point = browser.view.mapFromGlobal(
+            browser.view.viewport().mapToGlobal(click_point)
+        )
+
+        # customContextMenuRequested doesn't currently seem to work in testing.
+        # with qtbot.waitSignal(browser.view.customContextMenuRequested):
+        #     qtbot.mouseClick(browser.view, Qt.RightButton, pos=right_click_point)
+
+        # therefore let's manually trigger the slot
+
+        browser._openMenu(right_click_point)
+
+        with qtbot.waitSignal(browser.deletionRequested):
+            qtbot.mouseClick(browser.contextual_menu, Qt.LeftButton)

beat/editor/widgets/assetbrowser.py

@@ -98,6 +98,7 @@ class AssetBrowser(QWidget):
         """Constructor"""
 
         super(AssetBrowser, self).__init__(parent)
+        self.contextual_menu = None
         self.filesystem_model = QFileSystemModel()
         self.filesystem_model.setNameFilters(["*.json"])
         self.filesystem_model.setNameFilterDisables(False)
@@ -114,11 +115,11 @@ class AssetBrowser(QWidget):
         layout = QVBoxLayout(self)
         layout.addWidget(self.view)
 
-        self.view.doubleClicked.connect(self.__onItemSelected)
-        self.view.customContextMenuRequested.connect(self.__openMenu)
+        self.view.doubleClicked.connect(self._onItemDoubleClicked)
+        self.view.customContextMenuRequested.connect(self._openMenu)
 
     @pyqtSlot("QModelIndex")
-    def __onItemSelected(self, index):
+    def _onItemDoubleClicked(self, index):
         """When an item is selected, emit the jsonSelected signal with
         the corresponding JSON file path.
         """
@@ -133,23 +134,44 @@ class AssetBrowser(QWidget):
             )
 
     @pyqtSlot("QPoint")
-    def __openMenu(self, position):
+    def _openMenu(self, position):
+        """Handle the contextual menu"""
 
         indexes = self.view.selectedIndexes()
         if indexes and indexes[0].data().endswith(".json"):
-            menu = QMenu()
-            action = menu.addAction(self.tr("Delete"))
-            action.triggered.connect(self.__onDelete)
+            if self.contextual_menu is None:
+                self.contextual_menu = QMenu()
+                action = self.contextual_menu.addAction(self.tr("Delete"))
+                action.triggered.connect(self._onDelete)
 
-            menu.exec_(self.view.viewport().mapToGlobal(position))
+            self.contextual_menu.popup(self.view.viewport().mapToGlobal(position))
 
     @pyqtSlot()
-    def __onDelete(self):
+    def _onDelete(self):
+        """Delete the selected asset"""
+
         file_index, _ = self.view.selectedIndexes()
         source_index = self.proxy_model.mapToSource(file_index)
         path = self.filesystem_model.filePath(source_index)
         self.deletionRequested.emit(path)
 
+    @pyqtSlot(Asset)
+    def setCurrentAsset(self, asset):
+        """Set the current index of the view to match the asset"""
+
+        source_index = self.filesystem_model.index(asset.declaration_path)
+        self.view.setCurrentIndex(self.proxy_model.mapFromSource(source_index))
+
+    def currentAsset(self):
+        """Returns the asset matching the currently selected index"""
+
+        current_index = self.view.currentIndex()
+        source_index = self.proxy_model.mapToSource(current_index)
+        return Asset.from_path(
+            self.filesystem_model.rootPath(),
+            self.filesystem_model.filePath(source_index),
+        )
+
     def set_context(self, context):
         """Sets the root path of the prefix to edit"""