Decode json strings as Dates/Times if they're using a YAML-compatible format. Closes #9614 [Rick]

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@7613 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activesupport/CHANGELOG

 *SVN*
 
+* Decode json strings as Dates/Times if they're using a YAML-compatible format.  Closes #9614 [Rick]
+
 * Fixed cache_page to use the request url instead of the routing options when picking a save path #8614 [josh]
 
 * Object.subclasses_of includes anonymous subclasses.  [Jeremy Kemper]

activesupport/lib/active_support/json/decoding.rb

@@ -15,17 +15,26 @@ def decode(json)
       end
       
       protected
+        # matches YAML-formatted dates
+        DATE_REGEX = /^\d{4}-\d{2}-\d{2}|\d{4}-\d{1,2}-\d{1,2}[ \t]+\d{1,2}:\d{2}:\d{2}(\.[0-9]*)?(([ \t]*)Z|[-+]\d{2}?(:\d{2})?)?$/
 
         # Ensure that ":" and "," are always followed by a space
         def convert_json_to_yaml(json) #:nodoc:
-          scanner, quoting, marks = StringScanner.new(json), false, []
-
+          scanner, quoting, marks, pos, times = StringScanner.new(json), false, [], nil, []
           while scanner.scan_until(/(\\['"]|['":,\\]|\\.)/)
             case char = scanner[1]
             when '"', "'"
               if !quoting
                 quoting = char
+                pos = scanner.pos
               elsif quoting == char
+                if json[pos..scanner.pos-2] =~ DATE_REGEX
+                  # found a date, track the exact positions of the quotes so we can remove them later.
+                  # oh, and increment them for each current mark, each one is an extra padded space that bumps
+                  # the position in the final yaml output
+                  total_marks = marks.size
+                  times << pos+total_marks << scanner.pos+total_marks
+                end
                 quoting = false
               end
             when ":",","
@@ -37,7 +46,11 @@ def convert_json_to_yaml(json) #:nodoc:
             json
           else
             ranges = ([0] + marks.map(&:succ)).zip(marks + [json.length])
-            ranges.map { |(left, right)| json[left..right] }.join(" ")
+            output = ranges.collect! { |(left, right)| json[left..right] }.join(" ")
+            times.each do |pos|
+              output[pos-1] = ' '
+            end
+            output
           end
         end
     end

activesupport/test/json/decoding_test.rb

@@ -10,6 +10,12 @@ class TestJSONDecoding < Test::Unit::TestCase
     %({"returnTo":[1,"\\"a\\",", "b"]})        => {"returnTo" => [1, "\"a\",", "b"]},
     %({a: "'", "b": "5,000"})                  => {"a" => "'", "b" => "5,000"},
     %({a: "a's, b's and c's", "b": "5,000"})   => {"a" => "a's, b's and c's", "b" => "5,000"},
+    %({a: "2007-01-01"})                       => {'a' => Date.new(2007, 1, 1)}, 
+    %({a: "2007-01-01 01:12:34 Z"})            => {'a' => Time.utc(2007, 1, 1, 1, 12, 34)}, 
+    # no time zone
+    %({a: "2007-01-01 01:12:34"})              => {'a' => "2007-01-01 01:12:34"}, 
+    # needs to be *exact*
+    %({a: " 2007-01-01 01:12:34 Z "})          => {'a' => " 2007-01-01 01:12:34 Z "}, 
     %([])    => [],
     %({})    => {},
     %(1)     => 1,