lib/template_params/assertion.rb in template_params-0.1.0 vs lib/template_params/assertion.rb in template_params-0.1.1

@@ -1,10 +1,11 @@
+# frozen_string_literal: true
 require "method_source"
 
 module TemplateParams
+  # A simple assertion suitable for view template preconditions.
   class Assertion
-
     # @api public
     def initialize(type, options)
       @type = type
       @options = options
     end
@@ -43,11 +44,11 @@
 
     # Raises a `TypeError` if `value` is not of `@type`.
     # @api private
     def assert_type(value)
       unless @type.nil? || value.is_a?(@type) || allow_nil && value.nil?
-        fail TypeError, format("Expected %s, got %s", @type, value.class)
+        raise TypeError, format("Expected %s, got %s", @type, value.class)
       end
     end
 
     # Given a `NameError` and the block, return a string like:
     #
@@ -57,13 +58,14 @@
     #
     # `Proc#source` is provided by the `method_source` gem.
     #
     # @api private
     def udef_msg(name_error, block)
-      msg = "Undefined template parameter: #{name_error}"
+      prefix = "Undefined template parameter: #{name_error}"
       if block.respond_to?(:source)
-        msg << ": " + block.source.strip
+        format("%s: %s", prefix, block.source.strip)
+      else
+        prefix
       end
-      msg
     end
   end
 end