Fix constantize to handle names beginning with '::'. Closes #3803.

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@3571 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activesupport/CHANGELOG

@@ -1,5 +1,7 @@
 *SVN*
 
+* Fix constantize to properly handle names beginning with '::'. [Nicholas Seckar]
+
 * Make String#last return the string instead of nil when it is shorter than the limit [Scott Barron].
 
 * Added delegation support to Module that allows multiple delegations at once (unlike Forwardable in the stdlib) [DHH]. Example:

activesupport/lib/active_support/inflector.rb

@@ -143,9 +143,9 @@ def foreign_key(class_name, separate_class_name_and_id_with_underscore = true)
 
   def constantize(camel_cased_word)
     raise NameError, "#{camel_cased_word.inspect} is not a valid constant name!" unless
-      camel_cased_word.split("::").all? { |part| /^[A-Z]\w*$/ =~ part }
+      /^(::)?([A-Z]\w*)(::[A-Z]\w*)*$/ =~ camel_cased_word
 
-    camel_cased_word = "::#{camel_cased_word}" unless camel_cased_word[0, 2] == '::'
+    camel_cased_word = "::#{camel_cased_word}" unless $1
     Object.module_eval(camel_cased_word, __FILE__, __LINE__)
   end
 

activesupport/test/inflector_test.rb

@@ -274,7 +274,9 @@ def test_humanize
 
   def test_constantize
     assert_equal Ace::Base::Case, Inflector.constantize("Ace::Base::Case")
+    assert_equal Ace::Base::Case, Inflector.constantize("::Ace::Base::Case")
     assert_equal InflectorTest, Inflector.constantize("InflectorTest")
+    assert_equal InflectorTest, Inflector.constantize("::InflectorTest")
     assert_raises(NameError) { Inflector.constantize("UnknownClass") }
     assert_raises(NameError) { Inflector.constantize("An invalid string") }
   end