// This is kinda duplicated in CodeBlockAnalyzer.GetAssignmentStatus
private void CheckExpressionForNull(ISymbol symbol, ExpressionSyntax expression, MethodFlowAnalysis analysis = null)
{
var expressionValueType = expression.GetTypeOfValue(context.SemanticModel);
if (expressionValueType == ValueType.NotNull)
{
// Argument cannot be null, so move to the next
return;
}
if (expressionValueType == ValueType.Null)
{
context.ReportDiagnostic(MainAnalyzer.CreateReturnNull(expression.GetLocation(), symbol.ToString()));
return;
}
if (analysis == null)
{
context.ReportDiagnostic(MainAnalyzer.CreateReturnNull(expression.GetLocation(), symbol.ToString()));
return;
}
ExpressionStatus status = analysis.IsAlwaysAssigned(expression, expression);
if (!status.IsAssigned())
{
context.ReportDiagnostic(MainAnalyzer.CreateReturnNull(expression.GetLocation(), symbol.ToString()));
}
if (status == ExpressionStatus.AssignedWithUnneededConstraint)
{
context.ReportDiagnostic(MainAnalyzer.CreateUnneededConstraint(expression.GetLocation(), symbol.ToString()));
}
}
