gc.c: add minor marking and lazy sweeping options to GC.start

* gc.c (gc_start_internal): GC.start() now accepts two optional
  keyword arguments. These can be used to disable full_mark (minor
  mark only) or disable immediate_sweep (use lazy sweep). These new
  options are useful for benchmarking GC behavior, or performing minor
  GC out-of-band.
* test/ruby/test_gc.rb (class TestGc): tests for new options.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@44027 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 16 insertions, 0 deletions

diff --git a/test/ruby/test_gc.rb b/test/ruby/test_gc.rb
index 76104fedfe..f45983156e 100644
--- a/test/ruby/test_gc.rb
+++ b/test/ruby/test_gc.rb
@@ -48,6 +48,22 @@ class TestGc < Test::Unit::TestCase
     GC.enable
   end
 
+  def test_start_full_mark
+    GC.start(full_mark: false)
+    assert_nil GC.latest_gc_info(:major_by)
+
+    GC.start(full_mark: true)
+    assert_not_nil GC.latest_gc_info(:major_by)
+  end
+
+  def test_start_immediate_sweep
+    GC.start(immediate_sweep: false)
+    assert_equal false, GC.latest_gc_info(:immediate_sweep)
+
+    GC.start(immediate_sweep: true)
+    assert_equal true, GC.latest_gc_info(:immediate_sweep)
+  end
+
   def test_count
     c = GC.count
     GC.start