vagrant/lib/vagrant/util/which.rb

44 lines
1.4 KiB
Ruby

require "vagrant/util/platform"
module Vagrant
module Util
class Which
# Cross-platform way of finding an executable in the PATH.
#
# which('ruby') #=> /usr/bin/ruby
#
# This code is adapted from the following post by mislav:
# http://stackoverflow.com/questions/2108727/which-in-ruby-checking-if-program-exists-in-path-from-ruby
#
# @param [String] cmd The command to search for in the PATH.
# @return [String] The full path to the executable or `nil` if not found.
def self.which(cmd)
exts = nil
if !Platform.windows? || ENV['PATHEXT'].nil?
# If the PATHEXT variable is empty, we're on *nix and need to find
# the exact filename
exts = ['']
elsif File.extname(cmd).length != 0
# On Windows: if filename contains an extension, we must match that
# exact filename
exts = ['']
else
# On Windows: otherwise try to match all possible executable file
# extensions (.EXE .COM .BAT etc.)
exts = ENV['PATHEXT'].split(';')
end
ENV['PATH'].encode('UTF-8', 'binary', invalid: :replace, undef: :replace, replace: '').split(File::PATH_SEPARATOR).each do |path|
exts.each do |ext|
exe = "#{path}#{File::SEPARATOR}#{cmd}#{ext}"
return exe if File.executable? exe
end
end
return nil
end
end
end
end