@@ -1,10 +1,15 @@ require 'stringio' +# a module for suppressing or capturing STDOUT or STDERR. +# useful when shelling out to "noisy" applications or to suppress +# output during tests. module NoStdout module InstanceMethods + # Suppresses or redirects STDOUT inside the given block. + # supply an IO of your own to capture STDOUT, otherwise it's put + # in a new StringIO object. def no_stdout ( to = StringIO.new('','r+'), &block ) - # supply an IO of your own to capture STDOUT, otherwise it's put in a StringIO orig_stdout = $stdout $stdout = @alt_stdout = to result = yield @@ -12,21 +17,39 @@ module NoStdout result end + # returns the contents of STDOUT from the previous usage of + # no_stdout, or nil def last_stdout return nil unless @alt_stdout @alt_stdout.rewind @alt_stdout.read end + ## COPIED FROM ABOVE #### + + # Suppresses or redirects STDERR inside the given block. + # supply an IO of your own to capture STDERR, otherwise it's put + # in a new StringIO object. + def no_stderr ( to = StringIO.new('','r+'), &block ) + orig_stderr = $stderr + $stderr = @alt_stderr = to + result = yield + $stderr = orig_stderr + result + end + + # returns the contents of STDERR from the previous usage of + # no_stderr, or nil + def last_stderr + return nil unless @alt_stderr + @alt_stderr.rewind + @alt_stderr.read + end end - # TODO - explain / remember why this has two class_eval blocks - - # should one be an extend? def self.included klass klass.class_eval do include InstanceMethods end - klass.extend InstanceMethods end - end lib/no_stdout.rb f0abe614bec6405f0dda064e4e470a168806f048 davidlee david@davelee.com.au http://github.com/davidlee/state-fu/commit/f06a46a6508396fbe7fd238cc2c5e9093186ab89 f06a46a6508396fbe7fd238cc2c5e9093186ab89 2009-06-25T05:39:00-07:00 2009-06-25T05:39:00-07:00 commented no_stdout.rb (and added capture/redirect for 65d77ec7ebee9b8cc84c2b7f86f8ca903c3dcdd0 davidlee david@davelee.com.au