1 files changed, 51 insertions, 0 deletions
diff --git a/ruby_1_9_3/ext/pty/lib/expect.rb b/ruby_1_9_3/ext/pty/lib/expect.rb
new file mode 100644
index 0000000000..c15044bd2a
--- /dev/null
+++ b/ruby_1_9_3/ext/pty/lib/expect.rb
@@ -0,0 +1,51 @@
+$expect_verbose = false
+
+class IO
+  # Reads from the IO until pattern +pat+ matches or the +timeout+ is over.
+  # It returns an array with the read buffer, followed by the matches.
+  # If a block is given, the result is yielded to the block and returns nil.
+  #
+  # The optional timeout parameter defines, in seconds, the total time to wait
+  # for the pattern.  If the timeout expires or eof is found, nil is returned
+  # or yielded.  However, the buffer in a timeout session is kept for the next
+  # expect call.  The default timeout is 9999999 seconds.
+  def expect(pat,timeout=9999999)
+    buf = ''
+    case pat
+    when String
+      e_pat = Regexp.new(Regexp.quote(pat))
+    when Regexp
+      e_pat = pat
+    else
+      raise TypeError, "unsupported pattern class: #{pattern.class}"
+    end
+    @unusedBuf ||= ''
+    while true
+      if not @unusedBuf.empty?
+        c = @unusedBuf.slice!(0).chr
+      elsif !IO.select([self],nil,nil,timeout) or eof? then
+        result = nil
+        @unusedBuf = buf
+        break
+      else
+        c = getc.chr
+      end
+      buf << c
+      if $expect_verbose
+        STDOUT.print c
+        STDOUT.flush
+      end
+      if mat=e_pat.match(buf) then
+        result = [buf,*mat.to_a[1..-1]]
+        break
+      end
+    end
+    if block_given? then
+      yield result
+    else
+      return result
+    end
+    nil
+  end
+end
+