Fallback to clipboard when primary selection is unsupported

qutebrowser/browser/commands.py

@@ -1542,10 +1542,7 @@ class CommandDispatcher:
                        backend=usertypes.Backend.QtWebKit)
     def paste_primary(self):
         """Paste the primary selection at cursor position."""
-        try:
-            self.insert_text(utils.get_clipboard(selection=True))
-        except utils.SelectionUnsupportedError:
-            self.insert_text(utils.get_clipboard())
+        self.insert_text(utils.get_clipboard(selection=True, fallback=True))
 
     @cmdutils.register(instance='command-dispatcher', maxsplit=0,
                        scope='window')

qutebrowser/mainwindow/prompt.py

@@ -437,13 +437,13 @@ class LineEdit(QLineEdit):
         """Override keyPressEvent to paste primary selection on Shift + Ins."""
         if e.key() == Qt.Key_Insert and e.modifiers() == Qt.ShiftModifier:
             try:
-                text = utils.get_clipboard(selection=True)
+                text = utils.get_clipboard(selection=True, fallback=True)
             except utils.ClipboardError:  # pragma: no cover
-                pass
+                e.ignore()
             else:
                 e.accept()
                 self.insert(text)
-                return
+            return
         super().keyPressEvent(e)
 
     def __repr__(self):

qutebrowser/misc/miscwidgets.py

@@ -46,11 +46,12 @@ class MinimalLineEditMixin:
         """Override keyPressEvent to paste primary selection on Shift + Ins."""
         if e.key() == Qt.Key_Insert and e.modifiers() == Qt.ShiftModifier:
             try:
-                text = utils.get_clipboard(selection=True)
+                text = utils.get_clipboard(selection=True, fallback=True)
             except utils.ClipboardError:
-                text = utils.get_clipboard()
-            e.accept()
-            self.insert(text)
+                e.ignore()
+            else:
+                e.accept()
+                self.insert(text)
             return
         super().keyPressEvent(e)
 

qutebrowser/utils/utils.py

@@ -767,11 +767,23 @@ def set_clipboard(data, selection=False):
         QApplication.clipboard().setText(data, mode=mode)
 
 
-def get_clipboard(selection=False):
-    """Get data from the clipboard."""
+def get_clipboard(selection=False, fallback=False):
+    """Get data from the clipboard.
+
+    Args:
+        selection: Use the primary selection.
+        fallback: Fall back to the clipboard if primary selection is
+                  unavailable.
+    """
     global fake_clipboard
+    if fallback and not selection:
+        raise ValueError("fallback given without selection!")
+
     if selection and not supports_selection():
-        raise SelectionUnsupportedError
+        if fallback:
+            selection = False
+        else:
+            raise SelectionUnsupportedError
 
     if fake_clipboard is not None:
         data = fake_clipboard

tests/unit/utils/test_utils.py

@@ -836,6 +836,11 @@ class TestGetSetClipboard:
         with pytest.raises(utils.SelectionUnsupportedError):
             utils.get_clipboard(selection=True)
 
+    def test_get_unsupported_selection_fallback(self, clipboard_mock):
+        clipboard_mock.supportsSelection.return_value = False
+        clipboard_mock.text.return_value = 'text'
+        assert utils.get_clipboard(selection=True, fallback=True) == 'text'
+
     @pytest.mark.parametrize('selection', [True, False])
     def test_get_fake_clipboard(self, selection):
         utils.fake_clipboard = 'fake clipboard text'
@@ -847,6 +852,10 @@ class TestGetSetClipboard:
         clipboard_mock.supportsSelection.return_value = selection
         assert utils.supports_selection() == selection
 
+    def test_fallback_without_selection(self):
+        with pytest.raises(ValueError):
+            utils.get_clipboard(fallback=True)
+
 
 @pytest.mark.parametrize('keystr, expected', [
     ('<Control-x>', True),