[gnome-builder] completion: add re-entrance protection

[Christian Hergert <chergert src gnome org>]

commit 210b683a77bf4e78f3a28ce0d50f6fb24aaac6a5
Author: Christian Hergert <chergert redhat com>
Date:   Tue Jun 12 02:46:44 2018 -0700

    completion: add re-entrance protection
    
    We can accidentally get into this position during some update phases, so
    make sure we block it here.

 src/libide/completion/ide-completion.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)
---
diff --git a/src/libide/completion/ide-completion.c b/src/libide/completion/ide-completion.c
index 3d34b25e4..4bcc525cb 100644
--- a/src/libide/completion/ide-completion.c
+++ b/src/libide/completion/ide-completion.c
@@ -130,6 +130,9 @@ struct _IdeCompletion
    */
   guint block_count;
 
+  /* Re-entrancy protection for ide_completion_show(). */
+  guint showing;
+
   /*
    * The number of rows to display. This is propagated to the window if/when
    * the window is created.
@@ -1381,7 +1384,10 @@ ide_completion_show (IdeCompletion *self)
   if (ide_completion_is_blocked (self))
     IDE_EXIT;
 
-  g_signal_emit (self, signals [SHOW], 0);
+  self->showing++;
+  if (self->showing == 1)
+    g_signal_emit (self, signals [SHOW], 0);
+  self->showing--;
 
   IDE_EXIT;
 }