[widgets][assetwidget] Add currentAssetChanged signal

This signal will be emitted on change of the asset
to edit.

beat/editor/test/test_assetwidget.py

@@ -91,7 +91,9 @@ class TestAssetWidget:
             (asset_name, editor_type),
         ) in asset_type_prefix_entry_map.items():
             asset = Asset(test_prefix, asset_type, asset_name)
-            asset_widget.loadAsset(asset)
+            with qtbot.waitSignal(asset_widget.currentAssetChanged):
+                asset_widget.loadAsset(asset)
+
             assert isinstance(asset_widget.current_editor, editor_type)
 
     def test_dirty(
@@ -111,7 +113,8 @@ class TestAssetWidget:
             (asset_name, editor_type),
         ) in asset_type_prefix_entry_map.items():
             asset = Asset(test_prefix, asset_type, asset_name)
-            asset_widget.loadAsset(asset)
+            with qtbot.waitSignal(asset_widget.currentAssetChanged):
+                asset_widget.loadAsset(asset)
             assert not asset_widget.current_editor.isDirty()
 
             with qtbot.waitSignal(asset_widget.json_widget.textChanged):
@@ -143,7 +146,8 @@ class TestAssetWidget:
             (asset_name, editor_type),
         ) in asset_type_prefix_entry_map.items():
             asset = Asset(test_prefix, asset_type, asset_name)
-            asset_widget.loadAsset(asset)
+            with qtbot.waitSignal(asset_widget.currentAssetChanged):
+                asset_widget.loadAsset(asset)
 
             with qtbot.waitSignal(asset_widget.json_widget.textChanged):
                 asset_widget.current_editor.description_lineedit.selectAll()
@@ -301,7 +305,8 @@ class TestAssetWidget:
         monkeypatch.setattr(QMessageBox, "question", lambda *args: QMessageBox.Yes)
 
         asset = Asset(test_prefix, asset_type, asset_name)
-        asset_widget.loadAsset(asset)
+        with qtbot.waitSignal(asset_widget.currentAssetChanged):
+            asset_widget.loadAsset(asset)
         assert asset_widget.current_editor.asset_type != AssetType.UNKNOWN
         asset_widget.deleteAsset(asset.declaration_path)
         assert asset_widget.current_editor.asset_type == AssetType.UNKNOWN
@@ -327,5 +332,5 @@ class TestAssetWidget:
         with open(asset.declaration_path, "wt") as declaration_file:
             declaration_file.write("")
 
-        asset = Asset(test_prefix, asset_type, asset_name)
-        asset_widget.loadAsset(asset)
+        with qtbot.assertNotEmitted(asset_widget.currentAssetChanged):
+            asset_widget.loadAsset(asset)

beat/editor/widgets/assetwidget.py

@@ -27,6 +27,7 @@ import os
 import click
 import simplejson as json
 
+from PyQt5.QtCore import pyqtSignal
 from PyQt5.QtCore import pyqtSlot
 from PyQt5.QtCore import QFileSystemWatcher
 from PyQt5.QtCore import QTimer
@@ -124,6 +125,8 @@ class AssetWidget(QWidget):
     accordingly.
     """
 
+    currentAssetChanged = pyqtSignal([Asset])
+
     def __init__(self, parent=None):
         """Constructor"""
 
@@ -369,6 +372,7 @@ class AssetWidget(QWidget):
             self.watcher.addPath(asset.declaration_path)
             self.current_asset = asset
             self.__update_content()
+            self.currentAssetChanged.emit(asset)
 
     @pyqtSlot()
     def saveJson(self):