public static void ProcessOutRefInvocation(ISymbol symbol, BlockSyntax block, SemanticModel semanticModel, CancellationToken cancellationToken, RefCounterStatus status)
{
using (var pooledInvocations = InvocationWalker.Borrow(block))
{
foreach (var invocation in pooledInvocations.Invocations)
{
foreach (ArgumentSyntax arg in invocation.ArgumentList.Arguments)
{
if (arg.RefOrOutKeyword.IsKind(SyntaxKind.OutKeyword) || arg.RefOrOutKeyword.IsKind(SyntaxKind.RefKeyword))
{
var sym = ModelExtensions.GetSymbolInfo(semanticModel, arg.Expression, cancellationToken);
ISymbol argSymbol = sym.Symbol;
if (symbol.Equals(argSymbol))
{
status.RemainRef("init from out/ref call", arg.GetLocation());
status.IncAssignCounter("out/ref call parameter", arg.GetLocation());
if (LoopUtils.HasLoopBetween(invocation, block))
{
status.Skip("loop between ref/out call and var block", arg.GetLocation());
}
}
}
}
}
}
}
public static void ProcessReturnStatement(ISymbol local, BlockSyntax block, SemanticModel semanticModel, CancellationToken cancellationToken,
RefCounterStatus status)
{
using (var walker = ReturnValueWalker.Borrow(block, Search.TopLevel, semanticModel, cancellationToken))
{
foreach (var value in walker)
{
var returnedSymbol = semanticModel.GetSymbolSafe(value, cancellationToken);
if (SymbolComparer.Equals(local, returnedSymbol))
{
var method = block.FirstAncestor <MethodDeclarationSyntax>();
var access = block.FirstAncestor <AccessorDeclarationSyntax>();
bool isGet = false;
if (method != null)
{
isGet = KnownSymbol.IsGetMethodName(method.Identifier.ToString());
}
else if (access != null)
{
isGet = true;
}
if (isGet)
{
status.RemainRef("return value from get method", value.GetLocation());
}
else
{
status.ReleaseReference("return value from non get", value.GetLocation());
}
}
}
}
}
public static void CalcAssignmentValue(ExpressionSyntax variable, BlockSyntax block, SemanticModel semanticModel, CancellationToken cancellationToken,
RefCounterStatus refCounterStatus)
{
if (InitializeFromCreation(variable))
{
refCounterStatus.IncAssignCounter("initialize from new", variable.GetLocation());
refCounterStatus.AcquireReference("init from new", variable.GetLocation());
}
else if (InitializeFromTypeCastParameter(variable, semanticModel, cancellationToken, out var param))
{
refCounterStatus.IncAssignCounter("init cast from param", variable.GetLocation());
refCounterStatus.RemainRef("init cast from param", variable.GetLocation());
if (RightOfAssignmentUtils.RightSideOfAssignmentCount(param, block, semanticModel, cancellationToken) > 1)
{
refCounterStatus.Skip("cast from param also assigned to others", variable.GetLocation());
}
}
else if (InitializeFromNonGetMethod(variable, semanticModel, cancellationToken))
{
refCounterStatus.IncAssignCounter("initialize from non-get method", variable.GetLocation());
refCounterStatus.AcquireReference("init from non-get method", variable.GetLocation());
}
else if (InitializeFromGetMethod(variable, semanticModel, cancellationToken))
{
refCounterStatus.IncAssignCounter("initialize from get method", variable.GetLocation());
refCounterStatus.RemainRef("init from get method", variable.GetLocation());
}
else if (InitializeFromProperty(variable, semanticModel, cancellationToken))
{
refCounterStatus.IncAssignCounter("initialize from field/property", variable.GetLocation());
refCounterStatus.RemainRef("init from property", variable.GetLocation());
// nothing
}
else if (InitializeFromElement(variable, semanticModel, cancellationToken))
{
refCounterStatus.IncAssignCounter("initialize from element access", variable.GetLocation());
refCounterStatus.RemainRef("init from element access", variable.GetLocation());
}
else // assigned from other local variable, class field, or other expression
{
refCounterStatus.IncAssignCounter("initialize from unkown", variable.GetLocation());
refCounterStatus.Skip("unsupported initialization", variable.GetLocation());
}
}