private static void Handle(SyntaxNodeAnalysisContext context)
{
if (!context.IsExcludedFromAnalysis() &&
context.Node is AttributeSyntax attribute &&
Attribute.IsType(attribute, KnownSymbol.DependencyAttribute, context.SemanticModel, context.CancellationToken) &&
Attribute.TryFindArgument(attribute, 0, "dependentAssemblyArgument", out var argument) &&
context.SemanticModel.TryGetConstantValue(argument.Expression, context.CancellationToken, out string assemblyName) &&
!context.Compilation.ReferencedAssemblyNames.TryFirst(x => x.Name == assemblyName, out _))
{
context.ReportDiagnostic(Diagnostic.Create(REFL032DependencyMustExist.Descriptor, argument.GetLocation()));
}
}
/// <summary>
/// Attempt to retrieve information about the application of the
/// DefaultMemberAttribute:
///
/// - Specified member name
/// - Location of attribute
/// - Type symbol of type with attribute applied
///
/// Does not throw on failure.
/// </summary>
/// <param name="context">Context of attribute application.</param>
/// <param name="memberName">Member name specified by attribute.</param>
/// <param name="location">Location of attribute application.</param>
/// <param name="typeSymbol">Attribute target.</param>
/// <returns>Success</returns>
private static bool TryGetAttributeAndTypeInfo(
SyntaxNodeAnalysisContext context,
out string memberName,
out Location location,
out ITypeSymbol typeSymbol)
{
memberName = default(string);
location = default(Location);
typeSymbol = default(ITypeSymbol);
if (!(context.Node is AttributeSyntax attribute) ||
!Attribute.IsType(attribute, KnownSymbol.DefaultMemberAttribute, context.SemanticModel, context.CancellationToken))
{
return(false);
}
if (!Attribute.TryFindArgument(attribute, 0, "memberName", out var argument) ||
!context.SemanticModel.TryGetConstantValue(argument.Expression, context.CancellationToken, out string workingMemberName))
{
return(false);
}
if (!attribute.TryFirstAncestor(out ClassDeclarationSyntax classDeclaration))
{
return(false);
}
if (!context.SemanticModel.TryGetSymbol(classDeclaration, context.CancellationToken, out ITypeSymbol workingTypeSymbol))
{
return(false);
}
memberName = workingMemberName;
location = argument.GetLocation();
typeSymbol = workingTypeSymbol;
return(true);
}