dnd: Don't handle drops without uris

Add a check to assert nautilus_files_view_drop_proxy_received_uris is
not called with an empty source uri list.

Make nautilus_dnd_perform_drop return whether the drop event was
actually handled. Adjust callers accordingly.

Fixes: https://gitlab.gnome.org/GNOME/nautilus/-/issues/2787

4 files changed, 16 insertions, 11 deletions

diff --git a/src/nautilus-dnd.c b/src/nautilus-dnd.c
index a6039fe29..cd6fd110d 100644
--- a/src/nautilus-dnd.c
+++ b/src/nautilus-dnd.c
@@ -230,7 +230,7 @@ nautilus_dnd_get_preferred_action (NautilusFile *target_file,
     return GDK_ACTION_COPY;
 }
 
-void
+gboolean
 nautilus_dnd_perform_drop (NautilusFilesView *view,
                            const GValue      *value,
                            GdkDragAction      action,
@@ -241,18 +241,25 @@ nautilus_dnd_perform_drop (NautilusFilesView *view,
     if (!gdk_drag_action_is_unique (action))
     {
         /* TODO: Implement */
+        return FALSE;
     }
     else if (G_VALUE_HOLDS (value, G_TYPE_STRING))
     {
         nautilus_files_view_handle_text_drop (view,
                                               g_value_get_string (value),
                                               target_uri, action);
+        return TRUE;
     }
     else if (G_VALUE_HOLDS (value, GDK_TYPE_FILE_LIST))
     {
         GSList *source_file_list = g_value_get_boxed (value);
         GList *source_uri_list = NULL;
 
+        if (source_file_list == NULL)
+        {
+            return FALSE;
+        }
+
         for (GSList *l = source_file_list; l != NULL; l = l->next)
         {
             source_uri_list = g_list_prepend (source_uri_list, g_file_get_uri (l->data));
@@ -264,7 +271,11 @@ nautilus_dnd_perform_drop (NautilusFilesView *view,
                                                       target_uri,
                                                       action);
         g_list_free_full (source_uri_list, g_free);
+
+        return TRUE;
     }
+
+    return FALSE;
 }
 
 #define MAX_DRAWN_DRAG_ICONS 10
diff --git a/src/nautilus-dnd.h b/src/nautilus-dnd.h
index 426d7f89a..8fc59905a 100644
--- a/src/nautilus-dnd.h
+++ b/src/nautilus-dnd.h
@@ -26,7 +26,7 @@ GdkDragAction      nautilus_dnd_get_preferred_action             (NautilusFile
 GdkPaintable *     get_paintable_for_drag_selection              (GList            *selection,
                                                                   int               scale);
 
-void               nautilus_dnd_perform_drop                     (NautilusFilesView *view,
+gboolean           nautilus_dnd_perform_drop                     (NautilusFilesView *view,
                                                                   const GValue      *value,
                                                                   GdkDragAction      action,
                                                                   GFile             *target_location);
diff --git a/src/nautilus-list-base.c b/src/nautilus-list-base.c
index 05385f561..5bd797a36 100644
--- a/src/nautilus-list-base.c
+++ b/src/nautilus-list-base.c
@@ -785,9 +785,7 @@ on_item_drop (GtkDropTarget *target,
     /* In x11 the leave signal isn't emitted on a drop so we need to clear the timeout */
     g_clear_handle_id (&priv->hover_timer_id, g_source_remove);
 
-    nautilus_dnd_perform_drop (NAUTILUS_FILES_VIEW (self), value, actions, target_location);
-
-    return TRUE;
+    return nautilus_dnd_perform_drop (NAUTILUS_FILES_VIEW (self), value, actions, target_location);
 }
 
 static GdkDragAction
@@ -880,9 +878,7 @@ on_view_drop (GtkDropTarget *target,
     }
     #endif
 
-    nautilus_dnd_perform_drop (NAUTILUS_FILES_VIEW (self), value, actions, target_location);
-
-    return TRUE;
+    return nautilus_dnd_perform_drop (NAUTILUS_FILES_VIEW (self), value, actions, target_location);
 }
 
 void
diff --git a/src/nautilus-window.c b/src/nautilus-window.c
index 285febf0a..30299b19d 100644
--- a/src/nautilus-window.c
+++ b/src/nautilus-window.c
@@ -1520,9 +1520,7 @@ extra_drag_drop_cb (AdwTabBar    *self,
     GFile *target_location = nautilus_window_slot_get_location (slot);
     GdkDragAction action = GPOINTER_TO_INT (g_object_get_data (G_OBJECT (page), "drag-action"));
 
-    nautilus_dnd_perform_drop (view, value, action, target_location);
-
-    return TRUE;
+    return nautilus_dnd_perform_drop (view, value, action, target_location);
 }
 
 const GActionEntry win_entries[] =