/// <summary>
/// The DataFlowAnalysis API is fairly limited. It just provides a StartStatement and EndStatement.
/// However, an "if" statement includes the entire Block that comes after the if clause. This is
/// insufficient granularity. Consider the following example:
/// y = x as yType;
/// if (blah)
/// {
/// -optional code here-
/// y.ToString();
/// We need to pass to DataFlowAnalysis a statement that is before y.ToString() for the endStatement.
/// But if the firstStatement is the if clause, it includes the entire if block, of which endStatement is inside of.
/// This causes DataFlowAnalysis to throw an exception.
/// Stated differently (and more problematically), DataFlowAnalysis only works on statements in the same statementlist, ie the same block.
/// https://github.com/kislyuk/roslyn/blob/89169a3380e48fc834c72e38355867881d030e94/Src/Compilers/CSharp/Source/Compilation/SyntaxTreeSemanticModel.cs#L1902
///
/// Fortunately, from a practical perspective, it is likely a common scenario that in this case, the reason it is in a nested block is precisely because
/// it checked for null.
/// </summary>
/// <param name="blockOfInterest"></param>
/// <param name="node"></param>
/// <returns></returns>
private bool SameBlock(BlockSyntax blockOfInterest, SyntaxNode node)
{
BlockSyntax ourSymbolsBlock = node.Ancestors().OfType <BlockSyntax>().First();
return(ourSymbolsBlock.IsEquivalentTo(blockOfInterest));
}
