/// <summary>
/// Determines if the passed type passes the filter criteria or not
/// </summary>
/// <param name="ComparisonMode">The type comparison mode to implement</param>
/// <param name="Item">The item to be evaluated</param>
/// <param name="FilterItems">The collection of items that the compare item will be compared against</param>
/// <param name="IsBlacklist">True if it should behave like a blacklist, false if not</param>
/// <returns>True if the type is considered valid, false if not</returns>
public static bool IsValidItem(TypeComparison ComparisonMode, Type Item,
IEnumerable <TypeReference> FilterItems, bool IsBlacklist = true)
{
Func <Type, Type, bool> evaluationFunc = ComparisonMode.GetTypeComparisonDelegate();
bool foundMatch = false;
foreach (TypeReference filterItem in FilterItems)
{
foundMatch = evaluationFunc(Item, filterItem);
if (foundMatch)
{
break;
}
}
if (IsBlacklist)
{
return(!foundMatch);
}
else
{
return(foundMatch);
}
}
/// <summary>
/// Retrieves the function that should be used to compare two types
/// based on the selected enum mode
/// </summary>
/// <param name="ComparisonMode">The mode to get the function for</param>
/// <returns>The delegate for evaluating the two types</returns>
public static Func <Type, Type, bool> GetTypeComparisonDelegate(this TypeComparison ComparisonMode)
{
switch (ComparisonMode)
{
case TypeComparison.Equals:
return(CheckTypeEquality);
case TypeComparison.Inherits:
return(CheckTypeInherits);
case TypeComparison.Implements:
return(CheckTypeImplements);
default:
return(null);
}
}
/// <summary>
/// Determines whether the current <see cref="Type"/> derives from the specified <see cref="Type"/>.
/// </summary>
/// <param name="type">The <see cref="Type"/> to check for being a subclass.</param>
/// <param name="other">The <see cref="Type"/> to check for being the superclass.</param>
/// <param name="comparisonMethod">The method to use when comparing two <see cref="Type"/> objects.</param>
/// <returns>True if the type is a subclass, false if not.</returns>
/// <exception cref="ArgumentException"><paramref name="comparisonMethod"/> is
/// not a valid value in <see cref="TypeComparison"/>.</exception>
/// <exception cref="ArgumentNullException"><paramref name="type"/> or <paramref name="other"/> is null.</exception>
public static bool IsSubclassOf(this Type type, Type other, TypeComparison comparisonMethod)
{
if (type == null)
{
throw new ArgumentNullException(nameof(type));
}
if (other == null)
{
throw new ArgumentNullException(nameof(other));
}
switch (comparisonMethod)
{
case TypeComparison.Default:
return(type.IsSubclassOf(other));
case TypeComparison.AssemblyQualifiedName:
{
var current = type;
while (current != null)
{
if (string.Equals(current.AssemblyQualifiedName, other.AssemblyQualifiedName, StringComparison.Ordinal))
{
return(true);
}
if (current != typeof(object))
{
current = current.BaseType;
}
else
{
break;
}
}
return(false);
}
default:
throw new ArgumentException($"Invalid {nameof(TypeComparison)} value \"{comparisonMethod}\"!");
}
}
/// <summary>
/// Determines whether two <see cref="Type"/> objects represent the same type.
/// </summary>
/// <param name="type">The current <see cref="Type"/> to check with for equality.</param>
/// <param name="other">The other <see cref="Type"/> to check against for equality.</param>
/// <param name="comparisonMethod">The method to use when comparing two <see cref="Type"/> objects.</param>
/// <returns>True if the types are found to be equal, false if not.</returns>
/// <exception cref="ArgumentException"><paramref name="comparisonMethod"/> is
/// not a valid value in <see cref="TypeComparison"/>.</exception>
/// <exception cref="ArgumentNullException"><paramref name="type"/> or <paramref name="other"/> is null.</exception>
public static bool Equals(this Type type, Type other, TypeComparison comparisonMethod)
{
if (type == null)
{
throw new ArgumentNullException(nameof(type));
}
if (other == null)
{
throw new ArgumentNullException(nameof(other));
}
switch (comparisonMethod)
{
case TypeComparison.Default:
return(type.Equals(other));
case TypeComparison.AssemblyQualifiedName:
return(string.Equals(type.AssemblyQualifiedName, other.AssemblyQualifiedName, StringComparison.Ordinal));
default:
throw new ArgumentException($"Invalid {nameof(TypeComparison)} value \"{comparisonMethod}\"!");
}
}
public static bool CompareTo <TTypes, TOtherTypes>(this TTypes types, TOtherTypes otherTypes, TypeComparison comparisonType)
where TTypes : IReadOnlyList <Type>
where TOtherTypes : IReadOnlyList <Type>
{
var count = otherTypes.Count;
if (types.Count != count)
{
return(false);
}
switch (comparisonType)
{
case TypeComparison.Equality:
for (int i = 0; i < count; ++i)
{
if (types[i] != otherTypes[i])
{
return(false);
}
}
return(true);
case TypeComparison.AssignmentCompatibility:
for (int i = 0; i < count; ++i)
{
if (types[i].IsAssignableFrom(otherTypes[i]) == false)
{
return(false);
}
}
return(true);
case TypeComparison.TypeMatchersOrElseAssignmentCompatibility:
for (int i = 0; i < count; ++i)
{
if (types[i].IsTypeMatcher(out var typeMatcherType))
{
Debug.Assert(typeMatcherType.ImplementsTypeMatcherProtocol());
var typeMatcher = (ITypeMatcher)Activator.CreateInstance(typeMatcherType);
if (typeMatcher.Matches(otherTypes[i]) == false)
{
return(false);
}
}
else if (types[i].IsAssignableFrom(otherTypes[i]) == false)
{
return(false);
}
}
return(true);
default:
throw new ArgumentOutOfRangeException(nameof(comparisonType));
}
}
