internal static SafeRecursionCodeGenProps ParseFromAttribute(GeneratorExecutionContext context, MethodDeclarationSyntax methodSyntax, AttributeData attributeData)
{
var props = new SafeRecursionCodeGenProps();
foreach (var(name, value) in attributeData.NamedArguments)
{
switch (name)
{
case nameof(GenerateSafeRecursionAttribute.AccessLevel):
props.AccessLevel = (AccessLevel)value.Value;
break;
case nameof(GenerateSafeRecursionAttribute.GeneratedMethodName):
props.GeneratedMethodName = (string)value.Value;
break;
case nameof(GenerateSafeRecursionAttribute.ExtensionMethod):
props.ExtensionMethod = (ExtensionMethod)value.Value;
break;
case nameof(GenerateSafeRecursionAttribute.MutualRecursionId):
props.MutualRecursionId = (string)value.Value;
break;
case nameof(GenerateSafeRecursionAttribute.ExposeAsEntryPoint):
props.ExposeAsEntryPoint = (bool)value.Value;
break;
default:
context.LogInternalError(methodSyntax.GetLocation(), $"Unexpected GenerateSafeRecursionAttribute property '{name}' = '{value.Value}'");
break;
}
}
return(props);
}
public void Execute(GeneratorExecutionContext context)
{
// retrieve the populated receiver
if (!(context.SyntaxReceiver is RecursionSyntaxReceiver receiver))
{
return;
}
var compilation = context.Compilation;
if ("C#" != compilation.Language)
{
context.ReportUnsupportedLanguageError(compilation.Language);
return;
}
var goodCandidates = receiver.CandidateMethods.Select(methodSyntax =>
{
var methodModel = compilation.GetSemanticModel(methodSyntax.SyntaxTree);
var methodSymbol = methodModel.GetDeclaredSymbol(methodSyntax);
var attr = methodSymbol.GetAttributes().SingleOrDefault(a => a.AttributeClass.MatchesRuntimeType(TargetAttribute));
var codeGenProps = (attr != null) ? SafeRecursionCodeGenProps.ParseFromAttribute(context, methodSyntax, attr) : null;
return(new RecursiveMethodInfo(methodSyntax, methodSymbol, methodModel, codeGenProps));
})
.Where(t => t.CodeGenProps != null)
.GroupBy(t => t.CodeGenProps.MutualRecursionId ?? "") //convert null to empty string for GroupBy
.ToDictionary(g => g.Key, g => g.ToList());
if (!goodCandidates.TryGetValue("", out var simpleCandidates))
{
simpleCandidates = new List <RecursiveMethodInfo>();
}
context.Log($"Found {simpleCandidates.Count} method(s) for simple recursion and {goodCandidates.Count - 1} method group(s) for mutual recursion generation.");
foreach (var methodInfo in simpleCandidates)
{
try
{
var generatedCode = CalculatorClassGenerator.GenerateSimpleSafeRec(context, methodInfo);
if (generatedCode != null)
{
context.AddSource($"{methodInfo.MethodSymbol.ContainingType.Name}_{methodInfo.MethodSymbol.Name}_SafeRecursion.cs",
SourceText.From(generatedCode, Encoding.UTF8));
}
}
catch (Exception e)
{
context.LogInternalError(methodInfo.MethodSyntax.GetLocation(),
$"Processing '{methodInfo.MethodSymbol.ContainingType.Name}' resulted in an internal error '{e}'");
}
}
foreach (var(recursionId, methodInfos) in goodCandidates)
{
// skip the simple candidates
if (string.IsNullOrEmpty(recursionId))
{
continue;
}
var someMethodInfo = methodInfos.First();
try
{
var generatedCode = CalculatorClassGenerator.GenerateMutualSafeRec(context, methodInfos);
if (generatedCode != null)
{
context.AddSource($"{someMethodInfo.MethodSymbol.ContainingType.Name}_{recursionId}_SafeRecursion.cs",
SourceText.From(generatedCode, Encoding.UTF8));
}
}
catch (Exception e)
{
context.LogInternalError(someMethodInfo.MethodSyntax.Parent.GetLocation(),
$"Processing '{recursionId}' mutual recursion resulted in an internal error '{e}'");
}
}
}