Recursively calculates the size of a folder(path to folder is the first input in terminal). Found other solutions using system calls but decide to write my own.

calculate_folder_size.rb

if ARGV.count != 1 || !File.directory?(ARGV[0])
	p 'Please specify a folder.'	
	exit
end


def calculate_size(file)
	#p 'calculating ' + file

	if File.directory? file
		i = 0
		Dir.open(file).each do |f|
			i += calculate_size(file + "/" + f).to_i unless f == '.' || f == '..'
		end
		#p "#{file} directory size: " + i.to_s
		return i
	else
		#p "#{file} file size: " + File.size?(file).to_s
		return File.size?(file)
	end
end

size = calculate_size(ARGV[0])
p "#{size.to_f / 1024 / 1024} Mb"