wc

wc.rb

@@ -2,9 +2,9 @@
 
 require 'optparse'
 
-lines = 0
-words = 0
-bytes = 0
+total_lines = 0
+total_words = 0
+total_bytes = 0
 
 options = {}
 OptionParser.new do |opts|
@@ -13,26 +13,43 @@ OptionParser.new do |opts|
   opts.on('-c') { options[:bytes] = true }
 end.parse!
 
-input = if !ARGV.empty?
-          File.read(ARGV[0])
-        elsif !$stdin.tty?
-          $stdin.read
-        else
-          puts 'ファイルパスまたはパイプラインからの入力がありません。'
-          exit
-        end
+input_sources = ARGV.empty? ? [ARGF] : ARGV
 
-input.each_line do |line|
-  lines += 1
-  words += line.split.size
-  bytes += line.bytesize
+input_sources.each do |source|
+  lines = 0
+  words = 0
+  bytes = 0
+
+  begin
+    input = source == ARGF ? ARGF.read : File.read(source)
+
+    input.each_line do |line|
+      lines += 1
+      words += line.split.size
+      bytes += line.bytesize
+    end
+
+    total_lines += lines
+    total_words += words
+    total_bytes += bytes
+
+    options = { bytes: true, lines: true, words: true } if options.empty?
+    result = []
+    result << lines if options[:lines]
+    result << words if options[:words]
+    result << bytes if options[:bytes]
+
+    puts "#{result.join(' ')} #{source == ARGF ? '' : source}"
+  rescue Errno::ENOENT
+    puts "wc: #{source}: そのようなファイルやディレクトリはありません"
+  end
 end
 
-options = { bytes: true, lines: true, words: true } if options.empty?
-result = []
-result << lines if options[:lines]
-result << words if options[:words]
-result << bytes if options[:bytes]
+if input_sources.size > 1
+  total_result = []
+  total_result << total_lines if options[:lines]
+  total_result << total_words if options[:words]
+  total_result << total_bytes if options[:bytes]
 
-file_name = ARGV[0]
-puts "#{result.join(' ')} #{file_name}"
+  puts "#{total_result.join(' ')} total"
+end