Fix frozen object inspect

In the rails/rails CI build for Ruby master we found that some tests
were failing due to inspect on a frozen object being incorrect.

An object's instance variable count was incorrect when frozen causing
the object's inspect to not splat out the object.

This fixes the issue and adds a test for inspecting frozen objects.

Co-Authored-By: Jemma Issroff <jemmaissroff@gmail.com>
Co-Authored-By: Aaron Patterson <tenderlove@ruby-lang.org>

1 files changed, 9 insertions, 0 deletions

diff --git a/test/ruby/test_object.rb b/test/ruby/test_object.rb
index 83208bbcdb..a9d5d4b13e 100644
--- a/test/ruby/test_object.rb
+++ b/test/ruby/test_object.rb
@@ -993,4 +993,13 @@ class TestObject < Test::Unit::TestCase
       end
     EOS
   end
+
+  def test_frozen_inspect
+    obj = Object.new
+    obj.instance_variable_set(:@a, "a")
+    ins = obj.inspect
+    obj.freeze
+
+    assert_equal(ins, obj.inspect)
+  end
 end