private bool TryGetPreviousLocalId(SyntaxNode currentDeclarator, LocalDebugId currentId, out LocalDebugId previousId)
{
if (_syntaxMapOpt == null)
{
// no syntax map
// => the source of the current method is the same as the source of the previous method
// => relative positions are the same
// => synthesized ids are the same
previousId = currentId;
return(true);
}
SyntaxNode previousDeclarator = _syntaxMapOpt(currentDeclarator);
if (previousDeclarator == null)
{
previousId = default(LocalDebugId);
return(false);
}
int syntaxOffset = _previousMethod.CalculateLocalSyntaxOffset(previousDeclarator.SpanStart, previousDeclarator.SyntaxTree);
previousId = new LocalDebugId(syntaxOffset, currentId.Ordinal);
return(true);
}
private int CalculateSyntaxOffsetInPreviousMethod(SyntaxNode node)
{
// Note that syntax offset of a syntax node contained in a lambda body is calculated by the containing top-level method,
// not by the lambda method. The offset is thus relative to the top-level method body start. We can thus avoid mapping
// the current lambda symbol or body to the corresponding previous lambda symbol or body, which is non-trivial.
return(_previousTopLevelMethod.CalculateLocalSyntaxOffset(_lambdaSyntaxFacts.GetDeclaratorPosition(node), node.SyntaxTree));
}
