[gnome-builder] beautifier: Expand error message when beautifier isn't found

[Christian Hergert <chergert src gnome org>]

commit 237fd0ea81c18ad9fad994b6d9aabae8efe162f0
Author: vanadiae <vanadiae35 gmail com>
Date:   Fri Mar 19 17:11:55 2021 +0100

    beautifier: Expand error message when beautifier isn't found

 src/plugins/beautifier/gb-beautifier-editor-addin.c | 3 +++
 1 file changed, 3 insertions(+)
---
diff --git a/src/plugins/beautifier/gb-beautifier-editor-addin.c 
b/src/plugins/beautifier/gb-beautifier-editor-addin.c
index 722335af5..4dcbda5a1 100644
--- a/src/plugins/beautifier/gb-beautifier-editor-addin.c
+++ b/src/plugins/beautifier/gb-beautifier-editor-addin.c
@@ -53,6 +53,9 @@ process_launch_async_cb (GObject      *object,
 
   if (!gb_beautifier_process_launch_finish (self, result, &error))
     {
+      if (g_error_matches (error, G_IO_ERROR, G_IO_ERROR_NOT_FOUND))
+        g_prefix_error (&error, _("beautifier program missing, you must install it: "));
+
       /* translators: %s is replaced with the error message */
       ide_object_warning (self, _("Beautifier plugin: %s"), error->message);
     }