Add support for sorting by size

* add `--sort=size` flag
* add `-S` flag
* adjust `.travis.yml` to check the new flags

.travis.yml

@@ -28,6 +28,8 @@ script:
   - colorls --sort=time
   - colorls -U
   - colorls --sort=none
+  - colorls -S
+  - colorls --sort=size
   - colorls -h
   - colorls --gs
   - colorls spec/fixtures/symlinks

lib/colorls/core.rb

@@ -66,7 +66,7 @@ module ColorLS
       sort_contents(path)   if @sort
       group_contents(path)  if @group
 
-      @total_content_length = @contents.length
+      @total_content_length = @contents.count
 
       return @contents unless @long
       init_user_lengths(path)
@@ -114,6 +114,8 @@ module ColorLS
       case @sort
       when :time
         @contents.sort_by! { |a| -File.mtime(File.join(path, a)).to_f }
+      when :size
+        @contents.sort_by! { |a| -File.size(File.join(path, a)) }
       else
         @contents.sort! { |a, b| a.casecmp(b) }
       end

lib/colorls/flags.rb

@@ -57,10 +57,16 @@ module ColorLS
       options.on('--sf', '--sort-files', 'sort files first')                                  { @opts[:group] = :files }
       options.on('-t', 'sort by modification time, newest first')                             { @opts[:sort] = :time }
       options.on('-U', 'do not sort; list entries in directory order')                        { @opts[:sort] = false }
-      options.on('--sort=WORD', %w[none time], 'sort by WORD instead of name: none, time (-t)') do |word|
+      options.on('-S', 'sort by file size, largest first')                                    { @opts[:sort] = :size }
+      options.on(
+        '--sort=WORD',
+        %w[none time size],
+        'sort by WORD instead of name: none, size (-S), time (-t)'
+      ) do |word|
         @opts[:sort] = case word
                        when 'none' then false
                        when 'time' then :time
+                       when 'size' then :size
                        end
       end
 

spec/fixtures/a-file

@@ -0,0 +1,3 @@
+Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.
+
+Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.

spec/fixtures/z-file

@@ -0,0 +1 @@
+Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.

spec/flags_spec.rb

@@ -79,6 +79,12 @@ RSpec.describe ColorLS::Flags do
     it { is_expected.to match(expected) }
   end
 
+  context 'with --sort=size flag' do
+    let(:args) { ['--sort=size', FIXTURES] }
+
+    it { is_expected.to match(/a-file.+z-file.+symlinks/) } # sorts results by size
+  end
+
   context 'with --dirs flag' do
     let(:args) { ['--dirs', FIXTURES] }