@@ -170,7 +170,8 @@ module I18n # interpolation). def interpolate(locale, string, values = {}) return string unless string.is_a?(String) && !values.empty? - string.gsub(INTERPOLATION_SYNTAX_PATTERN) do + + s = string.gsub(INTERPOLATION_SYNTAX_PATTERN) do escaped, key = $1, $2.to_sym if escaped "{{#{key}}}" @@ -179,12 +180,20 @@ module I18n else "%{#{key}}" end - end % values + end + values.each { |key, value| values[key] = value.call if interpolate_lambda?(value, s, key) } + s % values rescue KeyError => e raise MissingInterpolationArgument.new(values, string) end + # returns true when the given value responds to :call and the key is + # an interpolation placeholder in the given string + def interpolate_lambda?(object, string, key) + object.respond_to?(:call) && string =~ /%\{#{key}\}|%\<#{key}>.*?\d*\.?\d*[bBdiouxXeEfgGcps]\}/ + end + # Loads a single translations file by delegating to #load_rb or # #load_yml depending on the file extension and directly merges the # data to the existing translations. Raises I18n::UnknownFileType lib/i18n/backend/base.rb @@ -20,6 +20,14 @@ module Tests assert_equal 'Hi !', interpolate(:default => 'Hi {{name}}!', :name => nil) end + def test_interpolation_given_a_lambda_as_a_value_it_calls_it_when_the_string_contains_the_key + assert_equal 'Hi David!', interpolate(:default => 'Hi {{name}}!', :name => lambda { 'David' }) + end + + def test_interpolation_given_a_lambda_as_a_value_it_does_not_call_it_when_the_string_does_not_contain_the_key + assert_nothing_raised { interpolate(:default => 'Hi!', :name => lambda { raise 'fail' }) } + end + def test_interpolation_given_interpolation_values_but_missing_a_key_it_raises_a_missing_interpolation_argument_exception assert_raises(I18n::MissingInterpolationArgument) do interpolate(:default => '{{foo}}', :bar => 'bar') test/api/interpolation.rb 9be3d4a311b5bf583eec5d39986176cc40c112f2 Sven Fuchs svenfuchs@artweb-design.de http://github.com/lawrencepit/i18n/commit/0e7546d49d861618d98efd04291614a78b793fdc 0e7546d49d861618d98efd04291614a78b793fdc 2009-08-26T08:47:03-07:00 2009-08-26T08:47:03-07:00 Allow to use lambdas as interpolation values. E.g. I18n.t(:default => 'Hi {{name}}!', :name => lambda { 'David' }) would now return "Hi David!". This is particularly useful when client code (such as ActiveRecord Validations) provides a couple of possible interpolation values without knowing which of them will be actually used by translators. Expensive lookups of such values can now be wrapped into a lambda and passed as interpolation values. 08e3c0f7a5f563350ed0a181f8b1740712b70d3f Sven Fuchs svenfuchs@artweb-design.de