Module: OpenString::ClassMethods

Included in:
String
Defined in:
lib/open_string.rb

Overview

Methods meant to be members of the String class need to go in here. The machinery here is a little odd: since the randomize declaration isn’t prefaced with a self, it doesn’t look static. Once String is set to extend OpenInteger::ClassMethods, this is treated like a static String method.

If this inner module wasn’t created and, instead, String was set to include OpenString, consumers would need to call static methods via OpenString like so: OpenString.randomize(10, CharacterSets.all).

Instance Method Summary collapse

Instance Method Details

#randomize(length, *charsets) ⇒ Object

Public: Generates a randomized string of a length specified by length.

length

The number of characters to include in the string

*charsets

Arrays of character sets to use in generating the random

string. This can take array literals, variables, or constants. Some
character sets are predefined in test/support/character_sets.rb

:section: Examples # Generates a 10-character string using only lowercase letters str = String.randomize(10, CharacterSets.lowercase)

# Generates a 5-character string using only [‘a’, ‘s’, ‘d’, ‘1’, ‘2’, ‘3’] str = String.randomize(5, %w(a s d 1 2 3))

Raises:

  • (ArgumentError) 


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# File 'lib/open_string.rb', line 40

def randomize(length, *charsets)
  raise(ArgumentError,
        'Do not pass nil for length.') if length.nil?
  raise(ArgumentError,
        'Length must be a non-zero positive integer.') if length < 1
  raise(ArgumentError,
        'Specify a character set.') if charsets.empty?

  Array.new(length) { charsets.flatten.sample }.join
end