Add IO#getbyte

mrbgems/mruby-io/README.md

@@ -59,7 +59,7 @@ Add the line below to your build configuration.
 | IO#fileno, IO#to_i         |    o     |      |
 | IO#flush                   |    o     |      |
 | IO#fsync                   |          |      |
-| IO#getbyte                 |          |      |
+| IO#getbyte                 |    o     |      |
 | IO#getc                    |    o     |      |
 | IO#gets                    |    o     |      |
 | IO#internal_encoding       |          |      |
@@ -93,7 +93,7 @@ Add the line below to your build configuration.
 | IO#sysseek                 |    o     |      |
 | IO#syswrite                |    o     |      |
 | IO#to_io                   |          |      |
-| IO#ungetbyte               |          |      |
+| IO#ungetbyte               |    o     |      |
 | IO#ungetc                  |    o     |      |
 | IO#write                   |    o     |      |
 | IO#write_nonblock          |          |      |

mrbgems/mruby-io/mrblib/io.rb

@@ -184,6 +184,11 @@ class IO
     nil
   end
 
+  def ungetbyte(substr)
+    substr = substr.chr if substr.is_a? Integer
+    ungetc substr
+  end
+
   def read(length = nil, outbuf = "")
     unless length.nil?
       unless length.is_a? Integer
@@ -296,6 +301,12 @@ class IO
     end
   end
 
+  def getbyte
+    ret = getc
+    return ret.getbyte 0 if ret
+    ret
+  end
+
   # 15.2.20.5.3
   def each(&block)
     return to_enum unless block

mrbgems/mruby-io/test/io.rb

@@ -105,6 +105,15 @@ assert('IO#getc', '15.2.20.5.8') do
   io.close
 end
 
+assert('IO#getbyte') do
+  io = IO.new(IO.sysopen($mrbtest_io_rfname))
+  $mrbtest_io_msg.split("").each do |ch|
+    assert_equal ch.getbyte(0), io.getbyte
+  end
+  assert_equal nil, io.getbyte
+  io.close
+end
+
 #assert('IO#gets', '15.2.20.5.9') do
 #assert('IO#initialize_copy', '15.2.20.5.10') do
 #assert('IO#print', '15.2.20.5.11') do