一种避免外部执行的方法:
对于捆绑器 1.2.x
require 'bundler/cli'
# intercepting $stdout into a StringIO
old_stdout, $stdout = $stdout, StringIO.new
# running the same code run in the 'bundler outdated' utility
Bundler::CLI.new.outdated('rails')
# storing the output
output = $stdout.string
# restoring $stdout
$stdout = old_stdout
对于捆绑器 1.3.x
require 'bundler/cli'
require 'bundler/friendly_errors'
# let's cheat the CLI class with fake exit method
module Bundler
class CLI
desc 'exit', 'fake exit' # this is required by Thor
def exit(*); end # simply do nothing
end
end
# intercepting $stdout into a StringIO
old_stdout, $stdout = $stdout, StringIO.new
# running the same code run in the 'bundler outdated' utility
Bundler.with_friendly_errors { Bundler::CLI.start(['outdated', 'rails']) }
# storing the output
output = $stdout.string
# restoring $stdout
$stdout = old_stdout