Hash#symbolize_keys skips keys that can't be symbolized. Closes #10500.

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@8454 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activesupport/CHANGELOG

 *SVN*
 
+* Hash#symbolize_keys skips keys that can't be symbolized.  #10500 [Brad Greenlee]
+
 * Ruby 1.9 compatibility.  #1689, #10466, #10468, #10554 [Cheah Chu Yeow, Pratik Naik, Jeremy Kemper, Dirkjan Bussink]
 
 * TimeZone#to_s uses UTC rather than GMT.  #1689 [Cheah Chu Yeow]

activesupport/lib/active_support/core_ext/hash/keys.rb

@@ -24,7 +24,7 @@ def stringify_keys!
         # Return a new hash with all keys converted to symbols.
         def symbolize_keys
           inject({}) do |options, (key, value)|
-            options[key.to_sym || key] = value
+            options[(key.to_sym rescue key) || key] = value
             options
           end
         end

activesupport/test/core_ext/hash_ext_test.rb

@@ -6,6 +6,11 @@ def setup
     @symbols = { :a  => 1, :b  => 2 }
     @mixed   = { :a  => 1, 'b' => 2 }
     @fixnums = {  0  => 1,  1  => 2 }
+    if RUBY_VERSION < '1.9.0'
+      @illegal_symbols = { "\0" => 1, "" => 2, [] => 3 }
+    else
+      @illegal_symbols = { [] => 3 }
+    end
   end
 
   def test_methods
@@ -22,16 +27,17 @@ def test_symbolize_keys
     assert_equal @symbols, @symbols.symbolize_keys
     assert_equal @symbols, @strings.symbolize_keys
     assert_equal @symbols, @mixed.symbolize_keys
-
-    assert_raises(NoMethodError) { { [] => 1 }.symbolize_keys }
   end
 
   def test_symbolize_keys!
     assert_equal @symbols, @symbols.dup.symbolize_keys!
     assert_equal @symbols, @strings.dup.symbolize_keys!
     assert_equal @symbols, @mixed.dup.symbolize_keys!
+  end
 
-    assert_raises(NoMethodError) { { [] => 1 }.symbolize_keys }
+  def test_symbolize_keys_preserves_keys_that_cant_be_symbolized
+    assert_equal @illegal_symbols, @illegal_symbols.symbolize_keys
+    assert_equal @illegal_symbols, @illegal_symbols.dup.symbolize_keys!
   end
 
   def test_symbolize_keys_preserves_fixnum_keys