lib/fd.rb in fd-0.5.0 vs lib/fd.rb in fd-0.6.0

@@ -5,10 +5,12 @@
 # Fd dumps the content of a file to the standard output.
 #
 class Fd
   class Error < StandardError; end
 
+  ESCAPE_CHARACTERS = %w[␀ ␇ ␈ ␉ ␊ ␋ ␌ ␍ ␡ ␛ ␠]
+
   attr_reader :line_length, :char_table
 
   # _line_length_ sets how many characters are displayed per @line.
   # Some <i>special non-printable/invisible characters</i> are displayed as their names.
   #
@@ -42,10 +44,14 @@
     @char_table[16] = '␡'
     @char_table[27] = '␛'
     @char_table[32] = '␠'
   end
 
+  def add_esc_sequence(chr)
+    "\e[31m#{chr}\e[0m"
+  end
+
   # dumps the given file _file_name_ to stdout.
   def dump(content)
     raise "Not the expected encoding of UFT-8, got #{content.encoding}" unless content.encoding == Encoding::UTF_8
 
     initialize_fields(content)
@@ -102,8 +108,10 @@
   def enough_space_in_line?(byte_count_in_line, bytes)
     byte_count_in_line + bytes.size <= line_length
   end
 
   def print_single_line
-    puts("#{format("%#{(3 * line_length) - 1}s", hex_values.join(' '))} |#{format("%#{2 * line_length}s", line)}")
+    puts("#{format("%#{(3 * line_length) - 1}s", hex_values.join(' '))} |#{format("%#{2 * line_length}s", line)}".
+      gsub(/([#{ESCAPE_CHARACTERS.join('')}])/, add_esc_sequence('\1'))
+    )
   end
 end