1 files changed, 132 insertions, 0 deletions
diff --git a/test/ruby/test_variable.rb b/test/ruby/test_variable.rb
index e50b681ce8..13b8a7905f 100644
--- a/test/ruby/test_variable.rb
+++ b/test/ruby/test_variable.rb
@@ -388,6 +388,61 @@ class TestVariable < Test::Unit::TestCase
     end
   end
 
+  class RemoveIvar
+    class << self
+      attr_reader :ivar
+
+      def add_ivar
+        @ivar = 1
+      end
+    end
+
+    attr_reader :ivar
+
+    def add_ivar
+      @ivar = 1
+    end
+  end
+
+  def add_and_remove_ivar(obj)
+    assert_nil obj.ivar
+    assert_equal 1, obj.add_ivar
+    assert_equal 1, obj.instance_variable_get(:@ivar)
+    assert_equal 1, obj.ivar
+
+    obj.remove_instance_variable(:@ivar)
+    assert_nil obj.ivar
+
+    assert_raise NameError do
+      obj.remove_instance_variable(:@ivar)
+    end
+  end
+
+  def test_remove_instance_variables_object
+    obj = RemoveIvar.new
+    add_and_remove_ivar(obj)
+    add_and_remove_ivar(obj)
+  end
+
+  def test_remove_instance_variables_class
+    add_and_remove_ivar(RemoveIvar)
+    add_and_remove_ivar(RemoveIvar)
+  end
+
+  class RemoveIvarGeneric < Array
+    attr_reader :ivar
+
+    def add_ivar
+      @ivar = 1
+    end
+  end
+
+  def test_remove_instance_variables_generic
+    obj = RemoveIvarGeneric.new
+    add_and_remove_ivar(obj)
+    add_and_remove_ivar(obj)
+  end
+
   class ExIvar < Hash
     def initialize
       @a = 1
@@ -407,12 +462,89 @@ class TestVariable < Test::Unit::TestCase
     }
   end
 
+  def test_exivar_resize_with_compaction_stress
+    omit "compaction doesn't work well on s390x" if RUBY_PLATFORM =~ /s390x/ # https://github.com/ruby/ruby/pull/5077
+    objs = 10_000.times.map do
+      ExIvar.new
+    end
+    EnvUtil.under_gc_compact_stress do
+      10.times do
+        x = ExIvar.new
+        x.instance_variable_set(:@resize, 1)
+        x
+      end
+    end
+    objs or flunk
+  end
+
   def test_local_variables_with_kwarg
     bug11674 = '[ruby-core:71437] [Bug #11674]'
     v = with_kwargs_11(v1:1,v2:2,v3:3,v4:4,v5:5,v6:6,v7:7,v8:8,v9:9,v10:10,v11:11)
     assert_equal(%i(v1 v2 v3 v4 v5 v6 v7 v8 v9 v10 v11), v, bug11674)
   end
 
+  def test_many_instance_variables
+    objects = [Object.new, Hash.new, Module.new]
+    objects.each do |obj|
+      1000.times do |i|
+        obj.instance_variable_set("@var#{i}", i)
+      end
+      1000.times do |i|
+        assert_equal(i, obj.instance_variable_get("@var#{i}"))
+      end
+    end
+  end
+
+  def test_local_variables_encoding
+    α = 1 or flunk
+    b = binding
+    b.eval("".encode("us-ascii"))
+    assert_equal(%i[α b], b.local_variables)
+  end
+
+  def test_genivar_cache
+    bug21547 = '[Bug #21547]'
+    klass = Class.new(Array)
+    instance = klass.new
+    instance.instance_variable_set(:@a1, 1)
+    instance.instance_variable_set(:@a2, 2)
+    Fiber.new do
+      instance.instance_variable_set(:@a3, 3)
+      instance.instance_variable_set(:@a4, 4)
+    end.resume
+    assert_equal 4, instance.instance_variable_get(:@a4), bug21547
+  end
+
+  def test_genivar_cache_free
+    str = +"hello"
+    str.instance_variable_set(:@x, :old_value)
+
+    str.instance_variable_get(:@x) # populate cache
+
+    Fiber.new {
+      str.remove_instance_variable(:@x)
+      str.instance_variable_set(:@x, :new_value)
+    }.resume
+
+    assert_equal :new_value, str.instance_variable_get(:@x)
+  end
+
+  def test_genivar_cache_invalidated_by_gc
+    str = +"hello"
+    str.instance_variable_set(:@x, :old_value)
+
+    str.instance_variable_get(:@x) # populate cache
+
+    Fiber.new {
+      str.remove_instance_variable(:@x)
+      str.instance_variable_set(:@x, :new_value)
+    }.resume
+
+    GC.start
+
+    assert_equal :new_value, str.instance_variable_get(:@x)
+  end
+
   private
   def with_kwargs_11(v1:, v2:, v3:, v4:, v5:, v6:, v7:, v8:, v9:, v10:, v11:)
     local_variables