Don't modify options parameters in-place. Closes #3819.

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@4584 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

3 files changed, 17 insertions, 2 deletions

diff --git a/activerecord/CHANGELOG b/activerecord/CHANGELOG
index 124546d579..1884c47d8e 100644
--- a/activerecord/CHANGELOG
+++ b/activerecord/CHANGELOG
@@ -1,5 +1,7 @@
 *SVN*
 
+* Don't modify options parameters in-place. #3819 [mpalmer@hezmatt.org]
+
 * PostgreSQL: correctly quote the ' in pk_and_sequence_for. #5462 [tietew@tietew.net]
 
 * PostgreSQL: correctly quote microseconds in timestamps. #5641 [rick@rickbradley.com]
diff --git a/activerecord/lib/active_record/base.rb b/activerecord/lib/active_record/base.rb
index 1c8c819efa..94b6645a17 100755
--- a/activerecord/lib/active_record/base.rb
+++ b/activerecord/lib/active_record/base.rb
@@ -1390,7 +1390,7 @@ module ActiveRecord #:nodoc:
         end
 
         def extract_options_from_args!(args) #:nodoc:
-          args.last.is_a?(Hash) ? args.pop : {}
+          args.last.is_a?(Hash) ? args.pop.dup : {}
         end
 
         VALID_FIND_OPTIONS = [ :conditions, :include, :joins, :limit, :offset,
diff --git a/activerecord/test/finder_test.rb b/activerecord/test/finder_test.rb
index 23b6508f99..229de2aa18 100644
--- a/activerecord/test/finder_test.rb
+++ b/activerecord/test/finder_test.rb
@@ -5,9 +5,10 @@ require 'fixtures/reply'
 require 'fixtures/entrant'
 require 'fixtures/developer'
 require 'fixtures/post'
+require 'fixtures/author'
 
 class FinderTest < Test::Unit::TestCase
-  fixtures :companies, :topics, :entrants, :developers, :developers_projects, :posts, :accounts
+  fixtures :authors, :companies, :topics, :entrants, :developers, :developers_projects, :posts, :accounts
 
   def test_find
     assert_equal(topics(:first).title, Topic.find(1).title)
@@ -449,6 +450,18 @@ class FinderTest < Test::Unit::TestCase
     assert_equal ["37signals","Summit","Microsoft", "Flamboyant Software", "Ex Nihilo", "RailsCore", "Leetsoft", "Jadedpixel"], Company.connection.select_values("SELECT name FROM companies ORDER BY id")
   end
 
+  def test_find_doesnt_mangle_parameters
+    author = Author.find(1)
+    
+    args = [:all, {:conditions => "body like '%t%'"}]
+
+    author.posts.each do |p|
+      assert_equal Post.find(p.id).comments.length,
+       p.comments.find(*args).length,
+       "Post ##{p.id} doesn't find correct number of comments"
+    end
+  end
+
   protected
     def bind(statement, *vars)
       if vars.first.is_a?(Hash)