public static void EnsureBadRequestObjectResultForError(this IActionResult actionResult,
String expectedErrorKey, String expectedErrorMsg)
{
SerializableError content = actionResult.EnsureBadRequestObjectResult <SerializableError>();
Assert.True(content.ContainsKey(expectedErrorKey));
Object rawElement = content[expectedErrorKey];
Assert.IsAssignableFrom <IEnumerable <String> >(rawElement);
IEnumerable <String> errorElements = (IEnumerable <String>)rawElement;
Assert.Single(errorElements);
Assert.Equal(expectedErrorMsg, errorElements.First());
}
