Merge pull request #34219 from wilddima/datetime-exception-message

Add message to exception in datetime type

activemodel/lib/active_model/type/date_time.rb

@@ -39,9 +39,9 @@ def fallback_string_to_time(string)
         end
 
         def value_from_multiparameter_assignment(values_hash)
-          missing_parameter = (1..3).detect { |key| !values_hash.key?(key) }
-          if missing_parameter
-            raise ArgumentError, missing_parameter
+          missing_parameters = (1..3).select { |key| !values_hash.key?(key) }
+          if missing_parameters.any?
+            raise ArgumentError, "Provided hash #{values_hash} doesn't contain necessary keys: #{missing_parameters}"
           end
           super
         end

activemodel/test/cases/type/date_time_test.rb

@@ -25,6 +25,17 @@ def test_string_to_time_with_timezone
         end
       end
 
+      def test_hash_to_time
+        type = Type::DateTime.new
+        assert_equal ::Time.utc(2018, 10, 15, 0, 0, 0), type.cast(1 => 2018, 2 => 10, 3 => 15)
+      end
+
+      def test_hash_with_wrong_keys
+        type = Type::DateTime.new
+        error = assert_raises(ArgumentError) { type.cast(a: 1) }
+        assert_equal "Provided hash {:a=>1} doesn't contain necessary keys: [1, 2, 3]", error.message
+      end
+
       private
 
         def with_timezone_config(default:)