test_proc.rb: test_local_variables

* test/ruby/test_proc.rb (test_local_variables): missing test for
  Binding#local_variables.  [Feature #8773]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@46644 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

test/ruby/test_proc.rb

@@ -1251,6 +1251,11 @@ class TestProc < Test::Unit::TestCase
     binding
   end
 
+  def test_local_variables
+    b = get_binding
+    assert_equal(%i[if case when begin end a], b.local_variables)
+  end
+
   def local_variables_of(bind)
     this_should_not_be_in_bind = 2
     bind.local_variables