redundancy_analyzer.rb in csscss-0.1.0

- old
+ new

@@ -3,23 +3,48 @@
     def initialize(raw_css)
       @raw_css = raw_css
     end
 
     def redundancies(minimum = nil)
-      rule_sets = CSSPool.CSS(@raw_css).rule_sets
+      rule_sets = Parser::Css.parse(@raw_css)
       matches = {}
+      parents = {}
       rule_sets.each do |rule_set|
         rule_set.declarations.each do |dec|
-          dec.property.downcase!
-          dec.expressions do |exp|
-            exp.value.downcase!
+          sel = rule_set.selectors
+
+          if parser = shorthand_parser(dec.property)
+            if new_decs = parser.parse(dec.property, dec.value)
+              if dec.property == "border"
+                %w(border-top border-right border-bottom border-left).each do |property|
+                  border_dec = Declaration.new(property, dec.value)
+                  parents[border_dec] ||= []
+                  (parents[border_dec] << dec).uniq!
+                  border_dec.parents = parents[border_dec]
+
+                  matches[border_dec] ||= []
+                  matches[border_dec] << sel
+                  matches[border_dec].uniq!
+                end
+              end
+
+              new_decs.each do |new_dec|
+                # replace any non-derivatives with derivatives
+                existing = matches.delete(new_dec) || []
+                existing << sel
+                parents[new_dec] ||= []
+                (parents[new_dec] << dec).uniq!
+                new_dec.parents = parents[new_dec]
+                matches[new_dec] = existing
+                matches[new_dec].uniq!
+              end
+            end
           end
 
-          dec_key = Declaration.from_csspool(dec)
-          sel = Selector.new(rule_set.selectors.map(&:to_s))
-          matches[dec_key] ||= []
-          matches[dec_key] << sel
+          matches[dec] ||= []
+          matches[dec] << sel
+          matches[dec].uniq!
         end
       end
 
       inverted_matches = {}
       matches.each do |declaration, selector_groups|
@@ -29,16 +54,39 @@
             inverted_matches[two_selectors] << declaration
           end
         end
       end
 
+
+      # trims any derivative declarations alongside shorthand
+      inverted_matches.each do |selectors, declarations|
+        redundant_derivatives = declarations.select do |dec|
+          dec.derivative? && declarations.detect {|dec2| dec2 > dec }
+        end
+        unless redundant_derivatives.empty?
+          inverted_matches[selectors] = declarations - redundant_derivatives
+        end
+
+        # border needs to be reduced even more
+        %w(width style color).each do |property|
+          decs = inverted_matches[selectors].select do |dec|
+            dec.derivative? && dec.property =~ /border-\w+-#{property}/
+          end
+          if decs.size == 4 && decs.map(&:value).uniq.size == 1
+            inverted_matches[selectors] -= decs
+            inverted_matches[selectors] << Declaration.new("border-#{property}", decs.first.value)
+          end
+        end
+      end
+
       if minimum
         inverted_matches.delete_if do |key, declarations|
           declarations.size < minimum
         end
       end
 
+      # combines selector keys by common declarations
       final_inverted_matches = inverted_matches.dup
       inverted_matches.to_a[0..-2].each_with_index do |(selector_group1, declarations1), index|
         inverted_matches.to_a[(index + 1)..-1].each do |selector_group2, declarations2|
           if declarations1 == declarations2
             final_inverted_matches.delete(selector_group1)
@@ -48,14 +96,33 @@
             final_inverted_matches[key].concat(declarations1 + declarations2).uniq!
           end
         end
       end
 
+      # sort hash by number of matches
       sorted_array = final_inverted_matches.sort {|(_, v1), (_, v2)| v2.size <=> v1.size }
       {}.tap do |sorted_hash|
         sorted_array.each do |key, value|
           sorted_hash[key.sort] = value.sort
         end
+      end
+    end
+
+    private
+    def shorthand_parser(property)
+      case property
+      when "background"   then Parser::Background
+      when "list-style"   then Parser::ListStyle
+      when "margin"       then Parser::Margin
+      when "padding"      then Parser::Padding
+      when "border"       then Parser::Border
+      when "border-width" then Parser::BorderWidth
+      when "border-style" then Parser::BorderStyle
+      when "border-color" then Parser::BorderColor
+      when "outline"      then Parser::Outline
+      when "font"         then Parser::Font
+      when "border-top", "border-right", "border-bottom", "border-left"
+        Parser::BorderSide
       end
     end
   end
 end