Merge pull request #4 from mediapress-ltd/jv-currency-formatting-perf…

…ormance

Allow `%Currency{}` structs in `currency_for_code/3`

lib/cldr/backend.ex

@@ -250,8 +250,8 @@ defmodule Cldr.Currency.Backend do
 
         ## Arguments
 
-        * `currency_code` is a `binary` or `atom` representation of an
-          ISO 4217 currency code.
+        * `currency_or_currency_code` is a `binary` or `atom` representation 
+           of an ISO 4217 currency code, or a `%Cldr.Currency{}` struct.
 
         ## Examples
 
@@ -288,14 +288,14 @@ defmodule Cldr.Currency.Backend do
             }}
 
         """
-        @spec currency_for_code(Cldr.Currency.code, Keyword.t()) ::
-                {:ok, Cldr.Currency.t} | {:error, {module(), String.t()}}
+        @spec currency_for_code(Cldr.Currency.code() | Cldr.Currency.t(), Keyword.t()) ::
+                {:ok, Cldr.Currency.t()} | {:error, {module(), String.t()}}
 
         def currency_for_code(
-              currency_code,
+              currency_or_currency_code,
               options \\ [locale: unquote(backend).default_locale()]
             ) do
-          Cldr.Currency.currency_for_code(currency_code, unquote(backend), options)
+          Cldr.Currency.currency_for_code(currency_or_currency_code, unquote(backend), options)
         end
 
         defp get_currency_metadata(code, nil) do

lib/cldr/currency.ex

@@ -771,8 +771,8 @@ defmodule Cldr.Currency do
 
   ## Arguments
 
-  * `currency_code` is a `binary` or `atom` representation of an
-    ISO 4217 currency code.
+  * `currency_or_currency_code` is a `binary` or `atom` representation
+      of an ISO 4217 currency code, or a `%Cldr.Currency{}` struct.
 
   * `backend` is any module that includes `use Cldr` and therefore
     is a `Cldr` backend module
@@ -820,16 +820,18 @@ defmodule Cldr.Currency do
 
   """
 
-  @spec currency_for_code(code, Cldr.backend(), Keyword.t()) ::
-          {:ok, t} | {:error, {module(), String.t()}}
+  @spec currency_for_code(code() | t(), Cldr.backend(), Keyword.t()) ::
+          {:ok, t()} | {:error, {module(), String.t()}}
 
-  def currency_for_code(currency_code, backend, options \\ []) do
+  def currency_for_code(currency_or_currency_code, backend, options \\ [])
+  def currency_for_code(%__MODULE__{} = currency, _backend, _options), do: {:ok, currency}
+
+  def currency_for_code(currency_code, backend, options) do
     {locale, backend} = Cldr.locale_and_backend_from(options[:locale], backend)
 
     with {:ok, code} <- known_currency_code(currency_code),
          {:ok, locale} <- Cldr.validate_locale(locale, backend),
          {:ok, currencies} <- currencies_for_locale(locale, backend) do
-
       {:ok, Map.get_lazy(currencies, code, fn -> Map.get(private_currencies(), code) end)}
     end
   end