[gnome-builder] libide/lsp: fix warning when using formatter

[Christian Hergert <chergert src gnome org>]

commit 650333bb3b7a9ab86048db353f97a8503fa95bf2
Author: Christian Hergert <chergert redhat com>
Date:   Mon Sep 26 17:45:19 2022 -0700

    libide/lsp: fix warning when using formatter
    
    This handles the NULL-set case from jsonrpc-glib which is "mv" for the
    return type, which is a container type (but not the one we want).

 src/libide/lsp/ide-lsp-formatter.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)
---
diff --git a/src/libide/lsp/ide-lsp-formatter.c b/src/libide/lsp/ide-lsp-formatter.c
index f17bad12b..d86769cfe 100644
--- a/src/libide/lsp/ide-lsp-formatter.c
+++ b/src/libide/lsp/ide-lsp-formatter.c
@@ -168,9 +168,15 @@ ide_lsp_formatter_apply_changes (IdeLspFormatter *self,
   g_assert (IDE_IS_LSP_FORMATTER (self));
   g_assert (text_edits != NULL);
 
-  if (!g_variant_is_container (text_edits))
+  /* We use "mv" to signify null/empty-set/nothing */
+  if (g_variant_is_of_type (text_edits, G_VARIANT_TYPE ("mv")))
+    IDE_EXIT;
+
+  /* We use "av" which is really "a<a{sv}>" */
+  if (!g_variant_is_of_type (text_edits, G_VARIANT_TYPE ("av")))
     {
-      g_warning ("variant is not a container, ignoring");
+      g_warning ("Unexpected result of type %s for text edits",
+                 g_variant_get_type_string (text_edits));
       IDE_EXIT;
     }