lib/option_initializer.rb in option_initializer-1.1.0 vs lib/option_initializer.rb in option_initializer-1.1.1

@@ -4,33 +4,46 @@
   def self.included base
     base.const_set :OptionInitializing, Class.new {
       attr_reader :options
       alias to_h options
 
+      const_set :VALIDATORS, []
+
       def initialize base, options
+        validate options
         @base    = base
         @options = options
       end
 
       def new *args, &block
         args = args.dup
         opts = @options
 
         # Convention. Deal with it.
         if args.last.is_a?(Hash)
+          validate args.last
           args[-1] = opts.merge(args.last)
         else
           args << opts.dup
         end
 
         @base.new(*args, &block)
       end
 
       def merge opts
+        validate opts
         self.class.new @base, @options.merge(opts)
       end
 
+      def validate hash
+        self.class.const_get(:VALIDATORS).each do |validator|
+          hash.each do |k, v|
+            validator.call k, v
+          end
+        end
+      end
+
       def method_missing sym, *args, &block
         # 1.8
         if @base.instance_methods.map(&:to_sym).include?(sym)
           @base.new(@options.dup).send sym, *args, &block
         else
@@ -39,13 +52,21 @@
       end
     } unless base.constants.map(&:to_sym).include?(:OptionInitializing)
 
     base.class_eval do
       class << self
-        if method_defined?(:option_initializer)
-          undef_method(:option_initializer)
+        [:option_initializer, :option_validator].each do |m|
+          undef_method(m) if method_defined?(m)
         end
       end
+
+      def base.option_validator &block
+        raise ArgumentError, "block must be given" unless block
+        raise ArgumentError, "invalid arity (expected: 2)" unless block.arity == 2
+        oi = self.const_get(:OptionInitializing)
+        oi.const_get(:VALIDATORS).push block
+      end
+
       def base.option_initializer *syms
         oi = self.const_get(:OptionInitializing)
 
         # Class methods
         syms.each do |sym|