# frozen_string_literal: true $expect_verbose = false # Expect library adds the IO instance method #expect, which does similar act to # tcl's expect extension. # # In order to use this method, you must require expect: # # require 'expect' # # Please see #expect for usage. class IO # call-seq: # IO#expect(pattern,timeout=9999999) -> Array # IO#expect(pattern,timeout=9999999) { |result| ... } -> nil # # Reads from the IO until the given +pattern+ 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. # # When called without a block, it waits until the input that matches the # given +pattern+ is obtained from the IO or the time specified as the # timeout passes. An array is returned when the pattern is obtained from the # IO. The first element of the array is the entire string obtained from the # IO until the pattern matches, followed by elements indicating which the # pattern which matched to the anchor in the regular expression. # # 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 = ''.dup case pat when String e_pat = Regexp.new(Regexp.quote(pat)) when Regexp e_pat = pat else raise TypeError, "unsupported pattern class: #{pat.class}" end @unusedBuf ||= '' while true if not @unusedBuf.empty? c = @unusedBuf.slice!(0) elsif !IO.select([self],nil,nil,timeout) or eof? then result = nil @unusedBuf = buf break else c = getc end buf << c if $expect_verbose STDOUT.print c STDOUT.flush end if mat=e_pat.match(buf) then result = [buf,*mat.captures] break end end if block_given? then yield result else return result end nil end end