private static IEnumerable <GenerateTheoryProperty> FindGenerateTheoryProperties(
GeneratorExecutionContext context,
IPropertySymbol propertySymbol,
INamedTypeSymbol containingType)
{
var descendants = propertySymbol.DescendantsAndSelf(x => x.OverriddenProperty).ToList();
var attributes = descendants.SelectMany(
d =>
d.GetAttributes()
.Where(
a =>
a.HasName(GenerateTheoryAttribute) || a.HasName(GenerateAsyncTheoryAttribute)
)
);
foreach (var attributeData in attributes)
{
Debug.Assert(
attributeData.AttributeClass != null,
"attributeData.AttributeClass != null"
);
var isAsync =
attributeData.HasName(GenerateAsyncTheoryAttribute);
var expectedInstanceSymbol = isAsync ? IAsyncTestInstance : ITestInstance;
var allInterfaces =
propertySymbol.Type.DescendantsAndSelf(x => x.AllInterfaces)
.Distinct(SymbolEqualityComparer.Default)
.OfType <INamedTypeSymbol>()
.ToList();
var testInstanceName =
allInterfaces
.Where(
i =>
i.IsGenericType &&
i.ConstructUnboundGenericType().Name.Equals("IEnumerable") &&
i.TypeArguments.Length == 1 &&
i.TypeArguments.Single()
.DescendantsAndSelf(x => x.AllInterfaces)
.Any(x => x.Name.Equals(expectedInstanceSymbol))
)
.Select(x => x.TypeArguments.Single().Name)
.FirstOrDefault();
if (testInstanceName == null)
{
const string messageCode = "TG001";
var message =
$"Properties implementing {attributeData.AttributeClass.Name} should return IEnumerable<{expectedInstanceSymbol}>";
context.ReportDiagnostic(
Diagnostic.Create(
new DiagnosticDescriptor(
messageCode,
message,
message,
"Testing",
DiagnosticSeverity.Error,
true
),
propertySymbol.Locations.FirstOrDefault()
)
);
}
else
{
yield return(new GenerateTheoryProperty(
propertySymbol,
attributeData,
isAsync,
testInstanceName,
containingType
));
}
}
}
