[gjs] function: Better message about call during GC

[Philip Chimento <pchimento src gnome org>]

commit 62a2b790920720b4eba1bc156964b1704f930841
Author: Philip Chimento <philip endlessm com>
Date:   Thu Jul 13 18:12:23 2017 -0700

    function: Better message about call during GC
    
    GJS can attempt to call back into JS during garbage collection if you
    implement vfunc_remove() on your container class. (Destroying a container
    will remove all its child widgets, and if you have implemented
    vfunc_remove() in JS then that will cause a JS call.)
    
    Note this possibility in the warning message, and also add whatever
    information we can get about the offending callback without calling into
    JSAPI.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=785040

 gi/function.cpp |   10 ++++++++--
 gi/value.cpp    |    5 +++--
 2 files changed, 11 insertions(+), 4 deletions(-)
---
diff --git a/gi/function.cpp b/gi/function.cpp
index 32d518a..6ac04a9 100644
--- a/gi/function.cpp
+++ b/gi/function.cpp
@@ -189,8 +189,14 @@ gjs_callback_closure(ffi_cif *cif,
         g_critical("Attempting to call back into JSAPI during the sweeping phase of GC. "
                    "This is most likely caused by not destroying a Clutter actor or Gtk+ "
                    "widget with ::destroy signals connected, but can also be caused by "
-                   "using the destroy() or dispose() vfuncs. Because it would crash the "
-                   "application, it has been blocked and the JS callback not invoked.");
+                   "using the destroy(), dispose(), or remove() vfuncs. "
+                   "Because it would crash the application, it has been "
+                   "blocked and the JS callback not invoked.");
+        if (trampoline->info) {
+            const char *name = g_base_info_get_name(static_cast<GIBaseInfo *>(trampoline->info));
+            g_critical("The offending callback was %s()%s.", name,
+                       trampoline->is_vfunc ? ", a vfunc" : "");
+        }
         /* A gjs_dumpstack() would be nice here, but we can't,
            because that works by creating a new Error object and
            reading the stack property, which is the worst possible
diff --git a/gi/value.cpp b/gi/value.cpp
index 2e6032d..6585375 100644
--- a/gi/value.cpp
+++ b/gi/value.cpp
@@ -143,8 +143,9 @@ closure_marshal(GClosure        *closure,
         g_critical("Attempting to call back into JSAPI during the sweeping phase of GC. "
                    "This is most likely caused by not destroying a Clutter actor or Gtk+ "
                    "widget with ::destroy signals connected, but can also be caused by "
-                   "using the destroy() or dispose() vfuncs. Because it would crash the "
-                   "application, it has been blocked and the JS callback not invoked.");
+                   "using the destroy(), dispose(), or remove() vfuncs. "
+                   "Because it would crash the application, it has been "
+                   "blocked and the JS callback not invoked.");
         if (hint) {
             gpointer instance;
             g_signal_query(hint->signal_id, &signal_query);