lib/monetize.rb in monetize-0.3.0 vs lib/monetize.rb in monetize-0.4.0

@@ -4,29 +4,32 @@
 require "monetize/core_extensions"
 require "monetize/version"
 
 module Monetize
 
+  CURRENCY_SYMBOLS = {
+    "$"    => "USD",
+    "€"    => "EUR",
+    "£"    => "GBP",
+    "R$"   => "BRL",
+    "R"    => "ZAR"
+  }
+
   # Class methods
   class << self
     # @attr_accessor [true, false] assume_from_symbol Use this to enable the
     #   ability to assume the currency from a passed symbol
     attr_accessor :assume_from_symbol
   end
 
   def self.parse(input, currency = Money.default_currency)
     input = input.to_s.strip
 
-    computed_currency = if assume_from_symbol && input =~ /^(\$|€|£)/
-                          case input
-                          when /^\$/ then "USD"
-                          when /^€/ then "EUR"
-                          when /^£/ then "GBP"
-                          end
-                        else
-                          input[/[A-Z]{2,3}/]
-                        end
+    computed_currency = compute_currency(input)
+    if not assume_from_symbol
+      computed_currency = input[/[A-Z]{2,3}/] || currency
+    end
 
     currency = computed_currency || currency || Money.default_currency
     currency = Money::Currency.wrap(currency)
 
     fractional = extract_cents(input, currency)
@@ -140,7 +143,32 @@
             end
 
     cents += minor
 
     negative ? cents * -1 : cents
+  end
+
+  private
+
+  def self.contains_currency_symbol?(amount)
+    currency_symbol_regex === amount
+  end
+
+  def self.compute_currency(amount)
+    if contains_currency_symbol?(amount)
+      matches = amount.match(currency_symbol_regex)
+      CURRENCY_SYMBOLS[matches[:symbol]]
+    else
+      amount[/[A-Z]{2,3}/]
+    end
+  end
+
+  def self.regex_safe_symbols
+    CURRENCY_SYMBOLS.keys.map { |key|
+      Regexp.escape(key)
+    }.join('|')
+  end
+
+  def self.currency_symbol_regex
+    /\A(?<symbol>#{regex_safe_symbols})/
   end
 end