added -d option flag for printing full duplicates

lib/csscss/cli.rb

@@ -10,6 +10,7 @@ def initialize(argv)
       @ignored_selectors  = []
       @match_shorthand    = true
       @ignore_sass_mixins = false
+      @find_duplicates    = false
     end
 
     def run
@@ -37,17 +38,19 @@ def execute
       end.join("\n")
 
       unless all_contents.strip.empty?
-        redundancies = RedundancyAnalyzer.new(all_contents).redundancies(
+        analyzer = RedundancyAnalyzer.new(all_contents)
+        redundancies = analyzer.redundancies(
           minimum:            @minimum,
           ignored_properties: @ignored_properties,
           ignored_selectors:  @ignored_selectors,
-          match_shorthand:    @match_shorthand
+          match_shorthand:    @match_shorthand,
+          duplicates:         @find_duplicates
         )
 
         if @json
           puts JSONReporter.new(redundancies).report
         else
-          report = Reporter.new(redundancies).report(verbose:@verbose, color:@color)
+          report = Reporter.new(redundancies).report(verbose:@verbose, color:@color, duplicates: analyzer.duplicates)
           puts report unless report.empty?
         end
       end
@@ -72,6 +75,10 @@ def parse(argv)
           @verbose = v
         end
 
+        opts.on("-d", "--[no-]duplicates", "Display Identical rules") do |d|
+          @find_duplicates = d
+        end
+
         opts.on("--[no-]color", "Colorize output", "(default is #{@color})") do |c|
           @color = c
         end

lib/csscss/redundancy_analyzer.rb

@@ -10,6 +10,7 @@ def redundancies(opts = {})
       ignored_properties = opts[:ignored_properties] || []
       ignored_selectors  = opts[:ignored_selectors] || []
       match_shorthand    = opts.fetch(:match_shorthand, true)
+      find_duplicates    = opts.fetch(:duplicates, false)
 
       rule_sets = Parser::Css.parse(@raw_css)
       matches = {}
@@ -55,6 +56,8 @@ def redundancies(opts = {})
         end
       end
 
+      @duplicates = find_all_duplicates(matches) if find_duplicates && matches
+
       inverted_matches = {}
       matches.each do |declaration, selector_groups|
         if selector_groups.size > 1
@@ -119,7 +122,33 @@ def redundancies(opts = {})
       end
     end
 
+    def duplicates(opts = {})
+      redundancies(opts) unless @duplicates
+      @duplicates
+    end
+
     private
+    def find_all_duplicates(matches)
+      # get the full selectors key declaration value hash
+      inverted = {}
+      duplicates = []
+      matches.each do |declaration, selector_group|
+        selector_group.each do |selector|
+          inverted[selector] ||= [] # at most empty
+          inverted[selector] << declaration unless inverted[selector].include?(declaration) # no duplicate values
+        end
+      end
+      inverted_copy = inverted
+      inverted.each do |key, value|
+        #remove the key value from inverted copy
+        inverted_copy.delete(key)
+        #if it still contains the value, log as duplicate
+        copy = inverted_copy.key(value)
+        duplicates << [copy, key, value] if copy
+      end
+      duplicates
+    end
+
     def shorthand_parser(property)
       case property
       when "background"   then Parser::Background

lib/csscss/reporter.rb

@@ -7,6 +7,7 @@ def initialize(redundancies)
     def report(options = {})
       verbose      = options.fetch(:verbose, false)
       should_color = options.fetch(:color, true)
+      duplicates = options.fetch(:duplicates, [])
 
       io = StringIO.new
       @redundancies.each do |selector_groups, declarations|
@@ -19,6 +20,10 @@ def report(options = {})
         end
       end
 
+      duplicates.each do |duplicate|
+        io.puts "[#{maybe_color(duplicate[0], :red, should_color)} AND #{maybe_color(duplicate[1], :red, should_color)}] are identical selectors that share #{maybe_color(duplicate[2].size, :red, should_color)} attributes"
+      end
+
       io.rewind
       io.read
     end

test/csscss/redundancy_analyzer_test.rb

@@ -286,6 +286,41 @@ module Csscss
       })
     end
 
+    it "correctly finds duplicates when duplicates flag is given" do
+      css = %$
+        h1, h2 { display: none; position: relative; outline:none}
+        .foo { display: none; width: 1px }
+        .bar { position: relative; width: 1px; outline: none }
+        .baz { display: none }
+        .alpha { width: 2px }
+        .beta { width: 2px }
+      $
+      analyzer = RedundancyAnalyzer.new(css)
+
+      analyzer.redundancies(duplicates:true).must_equal({
+        [sel(".bar"), sel("h1, h2")] => [dec("outline", "none"), dec("position", "relative")],
+        [sel(".bar"), sel(".foo")] => [dec("width", "1px")],
+        [sel(".baz"), sel(".foo"), sel("h1, h2")] => [dec("display", "none")],
+        [sel(".alpha"), sel(".beta")] => [dec("width", "2px")]
+      })
+
+      analyzer.duplicates.must_equal([
+        [sel(".beta"), sel(".alpha"), [dec("width", "2px")]]
+      ])
+    end
+
+    it "correctly finds no duplicates when the flag is given if there are none" do
+      css = %$
+        h1, h2 { display: none; position: relative; outline:none}
+        .foo { display: none; width: 1px }
+        .bar { position: relative; width: 1px; outline: none }
+        .baz { display: none }
+      $
+      analyzer = RedundancyAnalyzer.new(css)
+      analyzer.redundancies(duplicates:true)
+      analyzer.duplicates.must_be_empty
+    end
+
 
     # TODO: someday
     # it "reports duplication within the same selector" do

test/csscss/reporter_test.rb

@@ -30,6 +30,18 @@ module Csscss
      reporter.report(verbose:true, color:false).must_equal expected
     end
 
+    it "prints the regular results and the specific duplicates" do
+      reporter = Reporter.new({
+        [sel(".foo"), sel(".bar")] => [dec("width", "1px"), dec("border", "black")]
+      })
+
+      expected =<<-EXPECTED
+{.foo} AND {.bar} share 2 rules
+[foo AND bar] are identical selectors that share 2 attributes
+      EXPECTED
+      reporter.report(color:false, duplicates: [['foo', 'bar', %w('attribute', 'other_attribute')]]).must_equal expected
+    end
+
     it "prints a new line if there is nothing" do
       reporter = Reporter.new({})
       reporter.report().must_equal ""