Add a counter for compaction

Keep track of the number of times the compactor ran.  I would like to
use this as a way to keep track of inline cache reference updates.

1 files changed, 6 insertions, 0 deletions

diff --git a/test/ruby/test_gc_compact.rb b/test/ruby/test_gc_compact.rb
index bc26897386..e93e775279 100644
--- a/test/ruby/test_gc_compact.rb
+++ b/test/ruby/test_gc_compact.rb
@@ -54,4 +54,10 @@ class TestGCCompact < Test::Unit::TestCase
     assert GC.compact
     walk_ast ast
   end
+
+  def test_compact_count
+    count = GC.stat(:compact_count)
+    GC.compact
+    assert_equal count + 1, GC.stat(:compact_count)
+  end
 end