From cc89d494a6c552743f95e3f079eb0e2c3d97951b Mon Sep 17 00:00:00 2001
From: Jeremy Evans <code@jeremyevans.net>
Date: Wed, 3 Jul 2019 16:03:30 -0700
Subject: [PATCH] Use more explicit error message if wrong type when reopening
 class/module

Include the current class of the object in the error message.

Fixes [Bug #11460]
---
 test/ruby/test_class.rb  | 4 ++--
 test/ruby/test_module.rb | 4 ++--
 vm_insnhelper.c          | 4 ++--
 3 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/test/ruby/test_class.rb b/test/ruby/test_class.rb
index 93278a918f..7527a92960 100644
--- a/test/ruby/test_class.rb
+++ b/test/ruby/test_class.rb
@@ -588,12 +588,12 @@ def test_namescope_error_message
   def test_redefinition_mismatch
     m = Module.new
     m.module_eval "A = 1"
-    assert_raise_with_message(TypeError, /is not a class/) {
+    assert_raise_with_message(TypeError, /is not a class, it is a Integer/) {
       m.module_eval "class A; end"
     }
     n = "M\u{1f5ff}"
     m.module_eval "#{n} = 42"
-    assert_raise_with_message(TypeError, "#{n} is not a class") {
+    assert_raise_with_message(TypeError, "#{n} is not a class, it is a Integer") {
       m.module_eval "class #{n}; end"
     }
 
diff --git a/test/ruby/test_module.rb b/test/ruby/test_module.rb
index 604edf5f59..a60d48d20e 100644
--- a/test/ruby/test_module.rb
+++ b/test/ruby/test_module.rb
@@ -2340,12 +2340,12 @@ def test_define_method_with_unbound_method
   def test_redefinition_mismatch
     m = Module.new
     m.module_eval "A = 1"
-    assert_raise_with_message(TypeError, /is not a module/) {
+    assert_raise_with_message(TypeError, /is not a module, it is a Integer/) {
       m.module_eval "module A; end"
     }
     n = "M\u{1f5ff}"
     m.module_eval "#{n} = 42"
-    assert_raise_with_message(TypeError, "#{n} is not a module") {
+    assert_raise_with_message(TypeError, "#{n} is not a module, it is a Integer") {
       m.module_eval "module #{n}; end"
     }
 
diff --git a/vm_insnhelper.c b/vm_insnhelper.c
index 93b1ebfe7a..9e4c242e2b 100644
--- a/vm_insnhelper.c
+++ b/vm_insnhelper.c
@@ -3396,7 +3396,7 @@ static VALUE
 vm_check_if_class(ID id, rb_num_t flags, VALUE super, VALUE klass)
 {
     if (!RB_TYPE_P(klass, T_CLASS)) {
-	rb_raise(rb_eTypeError, "%"PRIsVALUE" is not a class", rb_id2str(id));
+	rb_raise(rb_eTypeError, "%"PRIsVALUE" is not a class, it is a %s", rb_id2str(id), rb_builtin_class_name(klass));
     }
     else if (VM_DEFINECLASS_HAS_SUPERCLASS_P(flags)) {
 	VALUE tmp = rb_class_real(RCLASS_SUPER(klass));
@@ -3419,7 +3419,7 @@ static VALUE
 vm_check_if_module(ID id, VALUE mod)
 {
     if (!RB_TYPE_P(mod, T_MODULE)) {
-	rb_raise(rb_eTypeError, "%"PRIsVALUE" is not a module", rb_id2str(id));
+	rb_raise(rb_eTypeError, "%"PRIsVALUE" is not a module, it is a %s", rb_id2str(id), rb_builtin_class_name(mod));
     }
     else {
 	return mod;
-- 
2.21.0