How to specify a file path using '~' in Ruby?

Question

If I do:

require \'inifile\'

# read an existing file
file = IniFile.load(\'~/.config\')
data = file[\'profile\'] # error here

puts data[\'region\']
         


        

Answer 1

Ruby has a method for this case. It is File::expand_path.

Converts a pathname to an absolute pathname. Relative paths are referenced from the current working directory of the process unless dir_string is given, in which case it will be used as the starting point. The given pathname may start with a “~”, which expands to the process owner’s home directory (the environment variable HOME must be set correctly). “~user” expands to the named user’s home directory.

require 'inifile'

# read an existing file
file = IniFile.load(File.expand_path('~/.config'))

Answer 2

When given ~ in a path at the command line, the shell converts ~ to the user's home directory. Ruby doesn't do that.

You could replace ~ using something like:

'~/.config'.sub('~', ENV['HOME'])
=> "/Users/ttm/.config"

or just reference the file as:

File.join(ENV['HOME'], '.config')
=> "/Users/ttm/.config"

or:

File.realpath('.config', ENV['HOME'])
=> "/Users/ttm/.config"