Refactor Condition so that it takes a parsed expression.

lib/liquid/condition.rb

@@ -3,7 +3,7 @@ module Liquid
   #
   # Example:
   #
-  #   c = Condition.new('1', '==', '1')
+  #   c = Condition.new(1, '==', 1)
   #   c.evaluate #=> true
   #
   class Condition #:nodoc:
@@ -28,9 +28,9 @@ module Liquid
     attr_accessor :left, :operator, :right
 
     def initialize(left = nil, operator = nil, right = nil)
-      @left = Expression.parse(left)
+      @left = left
       @operator = operator
-      @right = Expression.parse(right)
+      @right = right
       @child_relation  = nil
       @child_condition = nil
     end

lib/liquid/tags/case.rb

@@ -8,7 +8,7 @@ module Liquid
       @blocks = []
 
       if markup =~ Syntax
-        @left = $1
+        @left = Expression.parse($1)
       else
         raise SyntaxError.new(options[:locale].t("errors.syntax.case".freeze))
       end
@@ -58,7 +58,7 @@ module Liquid
 
         markup = $2
 
-        block = Condition.new(@left, '=='.freeze, $1)
+        block = Condition.new(@left, '=='.freeze, Expression.parse($1))
         block.attach(@nodelist)
         @blocks.push(block)
       end

lib/liquid/tags/if.rb

@@ -60,14 +60,14 @@ module Liquid
         expressions = markup.scan(ExpressionsAndOperators)
         raise(SyntaxError.new(options[:locale].t("errors.syntax.if".freeze))) unless expressions.pop =~ Syntax
 
-        condition = Condition.new($1, $2, $3)
+        condition = Condition.new(Expression.parse($1), $2, Expression.parse($3))
 
         while not expressions.empty?
           operator = expressions.pop.to_s.strip
 
           raise(SyntaxError.new(options[:locale].t("errors.syntax.if".freeze))) unless expressions.pop.to_s =~ Syntax
 
-          new_condition = Condition.new($1, $2, $3)
+          new_condition = Condition.new(Expression.parse($1), $2, Expression.parse($3))
           raise(SyntaxError.new(options[:locale].t("errors.syntax.if".freeze))) unless BOOLEAN_OPERATORS.include?(operator)
           new_condition.send(operator, condition)
           condition = new_condition
@@ -92,9 +92,9 @@ module Liquid
       end
 
       def parse_comparison(p)
-        a = p.expression
+        a = Expression.parse(p.expression)
         if op = p.consume?(:comparison)
-          b = p.expression
+          b = Expression.parse(p.expression)
           Condition.new(a, op, b)
         else
           Condition.new(a)