static IEnumerable <IMethodSymbol> GetOnChangedMethods(INamedTypeSymbol classSymbol, string methodName, string parameterType) =>
CommandHelper.GetMethods(classSymbol,
methodSymbol => methodSymbol.ReturnsVoid && methodSymbol.Name == methodName && methodSymbol.Parameters.Length < 2 &&
(methodSymbol.Parameters.Length == 0 || methodSymbol.Parameters.First().Type.ToDisplayStringNullable() == parameterType));
static string GetMethod(ContextInfo info, INamedTypeSymbol classSymbol, IFieldSymbol fieldSymbol, string methodName, string defaultMethodName, string parameterName, string parameterType)
{
var hasMethodName = methodName != null;
if (!hasMethodName)
{
methodName = defaultMethodName;
}
var methods = GetOnChangedMethods(classSymbol, methodName, parameterType);
if (methods.Count() == 2)
{
info.Context.ReportTwoSuitableMethods(classSymbol, fieldSymbol, methodName, parameterType);
return(methodName + "(" + parameterName + ");");
}
if (methods.Count() == 1)
{
if (methods.First().Parameters.Length == 0)
{
return(methodName + "();");
}
return(methodName + "(" + parameterName + ");");
}
if (!hasMethodName)
{
return(string.Empty);
}
info.Context.ReportOnChangedMethodNotFound(fieldSymbol, methodName, parameterType, CommandHelper.GetMethods(classSymbol, methodName));
return(null);
}
public static CommandGenerator Create(ContextInfo info, INamedTypeSymbol classSymbol, IMethodSymbol methodSymbol)
{
var hasError = false;
var isCommand = methodSymbol.ReturnsVoid;
var isAsyncCommand = methodSymbol.ReturnType.ToDisplayStringNullable().StartsWith("System.Threading.Tasks.Task");
if (methodSymbol.Parameters.Length > 1 || !(isCommand || isAsyncCommand))
{
info.Context.ReportIncorrectCommandSignature(methodSymbol);
hasError = true;
}
var parameterType = methodSymbol.Parameters.FirstOrDefault()?.Type.ToDisplayStringNullable() ?? string.Empty;
var canExecuteMethodName = CommandHelper.GetCanExecuteMethodName(methodSymbol, info.CommandAttributeSymbol);
if (canExecuteMethodName == null)
{
var candidate = CommandHelper.GetCanExecuteMethodCandidates(classSymbol, "Can" + methodSymbol.Name, parameterType);
canExecuteMethodName = candidate.SingleOrDefault()?.Name ?? "null";
}
else
{
var candidates = CommandHelper.GetCanExecuteMethodCandidates(classSymbol, canExecuteMethodName, parameterType);
if (!candidates.Any())
{
info.Context.ReportCanExecuteMethodNotFound(methodSymbol, canExecuteMethodName, parameterType, CommandHelper.GetMethods(classSymbol, canExecuteMethodName));
hasError = true;
}
}
return(hasError ? null : new CommandGenerator(methodSymbol, info.CommandAttributeSymbol, parameterType, canExecuteMethodName, isCommand));
}