Fixed to do force_encoding when decoding JSON.

Author: masato-hi

lib/spring/json.rb

@@ -321,11 +321,11 @@ def abbrev(s)
   # Unquote will raise an error if q contains control characters.
   def unquote(q)
     q = q[1...-1]
-    a = q.dup # allocate a big enough string
-    # In ruby >= 1.9, a[w] is a codepoint, not a byte.
+    # In ruby >= 1.9, q[r], a[w] is a codepoint, not a byte.
     if rubydoesenc?
-      a.force_encoding('UTF-8')
+      q.force_encoding('UTF-8')
     end
+    a = q.dup # allocate a big enough string
     r, w = 0, 0
     while r < q.length
       c = q[r]

test/unit/json_test.rb

@@ -8,5 +8,11 @@ class JsonTest < ActiveSupport::TestCase
 
   test 'can encode' do
     assert_equal('{}', Spring::JSON.dump({}))
-  end 
+  end
+
+  test 'can encode and decode unicode characters' do
+    encoded = Spring::JSON.dump({"unicode_example"=>"©".b})
+    assert_equal('{"unicode_example":"©"}'.b, encoded)
+    assert_equal({"unicode_example"=>"©"}, Spring::JSON.load(encoded))
+  end
 end