protected override void CheckInterfaces(DiagnosticBag diagnostics)
{
// Check declared interfaces and all base interfaces. This is necessary
// since references to all interfaces will be emitted to metadata
// and it's possible to define derived interfaces with weaker
// constraints than the base interfaces, at least in metadata.
var interfaces = this.InterfacesAndTheirBaseInterfacesNoUseSiteDiagnostics;
if (interfaces.IsEmpty)
{
// nothing to verify
return;
}
// Check constraints on the first declaration with explicit bases.
var singleDeclaration = this.FirstDeclarationWithExplicitBases();
if (singleDeclaration != null)
{
var corLibrary = this.ContainingAssembly.CorLibrary;
var conversions = new TypeConversions(corLibrary);
var location = singleDeclaration.NameLocation;
foreach (var pair in interfaces)
{
MultiDictionary <NamedTypeSymbol, NamedTypeSymbol> .ValueSet set = pair.Value;
foreach (var @interface in set)
{
@interface.CheckAllConstraints(DeclaringCompilation, conversions, location, diagnostics);
}
if (set.Count > 1)
{
NamedTypeSymbol other = pair.Key;
foreach (var @interface in set)
{
if ((object)other == @interface)
{
continue;
}
Debug.Assert(!other.Equals(@interface, TypeCompareKind.ConsiderEverything));
if (other.Equals(@interface, TypeCompareKind.IgnoreNullableModifiersForReferenceTypes))
{
diagnostics.Add(ErrorCode.WRN_DuplicateInterfaceWithNullabilityMismatchInBaseList, location, @interface, this);
}
else if (other.Equals(@interface, TypeCompareKind.IgnoreTupleNames))
{
diagnostics.Add(ErrorCode.ERR_DuplicateInterfaceWithTupleNamesInBaseList, location, @interface, other, this);
}
}
}
}
}
}
// finds syntax location where given type was inherited
// should be used for error reporting on unexpected inherited types.
private SourceLocation FindBaseRefSyntax(NamedTypeSymbol baseSym)
{
foreach (var decl in this.declaration.Declarations)
{
ImplementListSyntax implements = GetImplementListOpt(decl);
if (implements != null)
{
var baseBinder = this.DeclaringCompilation.GetBinder(implements);
// Wrap base binder in a location-specific binder that will avoid generic constraint checks.
baseBinder = baseBinder.WithAdditionalFlagsAndContainingMemberOrLambda(BinderFlags.SuppressConstraintChecks, this);
foreach (var baseTypeSyntax in implements.Types)
{
var b = baseTypeSyntax.Type;
var tmpDiag = DiagnosticBag.GetInstance();
var curBaseSym = baseBinder.BindType(b, tmpDiag).TypeSymbol;
tmpDiag.Free();
if (baseSym.Equals(curBaseSym))
{
return(new SourceLocation(b));
}
}
}
}
return(null);
}
internal override bool Equals(TypeSymbol t2, TypeCompareKind comparison)
{
if (ReferenceEquals(this, t2))
{
return(true);
}
var other = t2 as Nested;
return((object)other != null && string.Equals(MetadataName, other.MetadataName, StringComparison.Ordinal) &&
arity == other.arity &&
_containingType.Equals(other._containingType, comparison));
}
