require "active_support/core_ext/string/multibyte" require "active_support/i18n" module ActiveSupport module Inflector # Replaces non-ASCII characters with an ASCII approximation, or if none # exists, a replacement character which defaults to "?". # # transliterate('Ærøskøbing') # # => "AEroskobing" # # Default approximations are provided for Western/Latin characters, # e.g, "ø", "ñ", "é", "ß", etc. # # This method is I18n aware, so you can set up custom approximations for a # locale. This can be useful, for example, to transliterate German's "ü" # and "ö" to "ue" and "oe", or to add support for transliterating Russian # to ASCII. # # In order to make your custom transliterations available, you must set # them as the i18n.transliterate.rule i18n key: # # # Store the transliterations in locales/de.yml # i18n: # transliterate: # rule: # ü: "ue" # ö: "oe" # # # Or set them using Ruby # I18n.backend.store_translations(:de, i18n: { # transliterate: { # rule: { # 'ü' => 'ue', # 'ö' => 'oe' # } # } # }) # # The value for i18n.transliterate.rule can be a simple Hash that # maps characters to ASCII approximations as shown above, or, for more # complex requirements, a Proc: # # I18n.backend.store_translations(:de, i18n: { # transliterate: { # rule: ->(string) { MyTransliterator.transliterate(string) } # } # }) # # Now you can have different transliterations for each locale: # # I18n.locale = :en # transliterate('Jürgen') # # => "Jurgen" # # I18n.locale = :de # transliterate('Jürgen') # # => "Juergen" def transliterate(string, replacement = "?".freeze) raise ArgumentError, "Can only transliterate strings. Received #{string.class.name}" unless string.is_a?(String) I18n.transliterate(ActiveSupport::Multibyte::Unicode.normalize( ActiveSupport::Multibyte::Unicode.tidy_bytes(string), :c), replacement: replacement) end # Replaces special characters in a string so that it may be used as part of # a 'pretty' URL. # # parameterize("Donald E. Knuth") # => "donald-e-knuth" # parameterize("^trés|Jolie-- ") # => "tres-jolie" # # To use a custom separator, override the `separator` argument. # # parameterize("Donald E. Knuth", separator: '_') # => "donald_e_knuth" # parameterize("^trés|Jolie-- ", separator: '_') # => "tres_jolie" # # To preserve the case of the characters in a string, use the `preserve_case` argument. # # parameterize("Donald E. Knuth", preserve_case: true) # => "Donald-E-Knuth" # parameterize("^trés|Jolie-- ", preserve_case: true) # => "tres-Jolie" # def parameterize(string, separator: "-", preserve_case: false) # Replace accented chars with their ASCII equivalents. parameterized_string = transliterate(string) # Turn unwanted chars into the separator. parameterized_string.gsub!(/[^a-z0-9\-_]+/i, separator) unless separator.nil? || separator.empty? if separator == "-".freeze re_duplicate_separator = /-{2,}/ re_leading_trailing_separator = /^-|-$/i else re_sep = Regexp.escape(separator) re_duplicate_separator = /#{re_sep}{2,}/ re_leading_trailing_separator = /^#{re_sep}|#{re_sep}$/i end # No more than one of the separator in a row. parameterized_string.gsub!(re_duplicate_separator, separator) # Remove leading/trailing separator. parameterized_string.gsub!(re_leading_trailing_separator, "".freeze) end parameterized_string.downcase! unless preserve_case parameterized_string end end end