Turn class variable warnings into exceptions

This changes the following warnings:

* warning: class variable access from toplevel
* warning: class variable @foo of D is overtaken by C

into RuntimeErrors.  Handle defined?(@@foo) at toplevel
by returning nil instead of raising an exception (the previous
behavior warned before returning nil when defined? was used).

Refactor the specs to avoid the warnings even in older versions.
The specs were checking for the warnings, but the purpose of
the related specs as evidenced from their description is to
test for behavior, not for warnings.

Fixes [Bug #14541]

1 files changed, 14 insertions, 14 deletions

diff --git a/spec/ruby/language/defined_spec.rb b/spec/ruby/language/defined_spec.rb
index ed61ed3b53..f2da8a9293 100644
--- a/spec/ruby/language/defined_spec.rb
+++ b/spec/ruby/language/defined_spec.rb
@@ -275,9 +275,7 @@ describe "The defined? keyword for an expression" do
     end
 
     it "returns nil for an expression with '!' and an unset class variable" do
-      -> {
-        @result = defined?(!@@defined_specs_undefined_class_variable)
-      }.should complain(/class variable access from toplevel/)
+      @result = eval("class singleton_class::A; defined?(!@@doesnt_exist) end", binding, __FILE__, __LINE__)
       @result.should be_nil
     end
 
@@ -286,9 +284,7 @@ describe "The defined? keyword for an expression" do
     end
 
     it "returns nil for an expression with 'not' and an unset class variable" do
-      -> {
-        @result = defined?(not @@defined_specs_undefined_class_variable)
-      }.should complain(/class variable access from toplevel/)
+      @result = eval("class singleton_class::A; defined?(not @@doesnt_exist) end", binding, __FILE__, __LINE__)
       @result.should be_nil
     end
 
@@ -897,17 +893,21 @@ describe "The defined? keyword for a variable scoped constant" do
   end
 
   it "returns nil if the class scoped constant is not defined" do
-    -> {
-      @@defined_specs_obj = DefinedSpecs::Basic
-      defined?(@@defined_specs_obj::Undefined).should be_nil
-    }.should complain(/class variable access from toplevel/)
+    eval(<<-END, binding, __FILE__, __LINE__)
+      class singleton_class::A
+        @@defined_specs_obj = DefinedSpecs::Basic
+        defined?(@@defined_specs_obj::Undefined).should be_nil
+      end
+    END
   end
 
   it "returns 'constant' if the constant is defined in the scope of the class variable" do
-    -> {
-      @@defined_specs_obj = DefinedSpecs::Basic
-      defined?(@@defined_specs_obj::A).should == "constant"
-    }.should complain(/class variable access from toplevel/)
+    eval(<<-END, binding, __FILE__, __LINE__)
+      class singleton_class::A
+        @@defined_specs_obj = DefinedSpecs::Basic
+        defined?(@@defined_specs_obj::A).should == "constant"
+      end
+    END
   end
 
   it "returns nil if the local scoped constant is not defined" do