Accept multiple expected types for parameter validation

lib/droonga/catalog/base.rb

@@ -178,13 +178,19 @@ def validate_required_parameter(value, name)
         raise MissingRequiredParameter.new(name, @path) unless value
       end
 
-      def validate_parameter_type(expected, value, name)
-        unless value.is_a?(expected)
-          raise MismatchedParameterType.new(name,
-                                            expected,
-                                            value.class,
-                                            @path)
+      def validate_parameter_type(expected_types, value, name)
+        expected_types = [expected_types] unless expected_types.is_a?(Array)
+
+        if expected_types.any? do |type|
+             value.is_a?(type)
+           end
+          return
         end
+
+        raise MismatchedParameterType.new(name,
+                                          expected,
+                                          value.class,
+                                          @path)
       end
 
       def validate_valid_datetime(value, name)

lib/droonga/catalog/errors.rb

@@ -34,8 +34,17 @@ def initialize(name, path)
     end
 
     class MismatchedParameterType < ValidationError
-      def initialize(name, expected, actual, path)
-        super("\"#{name}\" must be a #{expected}, but a #{actual}.", path)
+      def initialize(name, expected_types, actual, path)
+        expected_types = [expected_types] unless expected_types.is_a?(Array)
+        message = nil
+        if expected_types.size == 1
+          message = "\"#{name}\" must be #{expected_types.first}, " +
+                      "but #{actual}."
+        else
+          message = "\"#{name}\" must be #{expected_types.join(" or ")}, " +
+                      "but #{actual}."
+        end
+        super(message, path)
       end
     end