private int ValidateBreakpointLocationWorker(
IVsTextBuffer pBuffer,
int iLine,
int iCol,
VsTextSpan[] pCodeSpan,
CancellationToken cancellationToken)
{
if (_breakpointService == null)
{
return(VSConstants.E_FAIL);
}
var textBuffer = _languageService.EditorAdaptersFactoryService.GetDataBuffer(pBuffer);
if (textBuffer != null)
{
var snapshot = textBuffer.CurrentSnapshot;
Document document = snapshot.AsText().GetDocumentWithFrozenPartialSemanticsAsync(cancellationToken).WaitAndGetResult(cancellationToken);
if (document != null)
{
var point = snapshot.GetPoint(iLine, iCol);
var length = 0;
if (pCodeSpan != null && pCodeSpan.Length > 0)
{
// If we have a non-empty span then it means that the debugger is asking us to adjust an
// existing span. In Everett we didn't do this so we had some good and some bad
// behavior. For example if you had a breakpoint on: "int i;" and you changed it to "int
// i = 4;", then the breakpoint wouldn't adjust. That was bad. However, if you had the
// breakpoint on an open or close curly brace then it would always "stick" to that brace
// which was good.
//
// So we want to keep the best parts of both systems. We want to appropriately "stick"
// to tokens and we also want to adjust spans intelligently.
//
// However, it turns out the latter is hard to do when there are parse errors in the
// code. Things like missing name nodes cause a lot of havoc and make it difficult to
// track a closing curly brace.
//
// So the way we do this is that we default to not intelligently adjusting the spans
// while there are parse errors. But when there are no parse errors then the span is
// adjusted.
var initialBreakpointSpan = snapshot.GetSpan(pCodeSpan[0]);
if (initialBreakpointSpan.Length > 0 && document.SupportsSyntaxTree)
{
var tree = document.GetSyntaxTreeAsync(cancellationToken).WaitAndGetResult(cancellationToken);
if (tree.GetDiagnostics(cancellationToken).Any(d => d.Severity == DiagnosticSeverity.Error))
{
return(VSConstants.E_FAIL);
}
}
// If a span is provided, and the requested position falls in that span, then just
// move the requested position to the start of the span.
// Length will be used to determine if we need further analysis, which is only required when text spans multiple lines.
if (initialBreakpointSpan.Contains(point))
{
point = initialBreakpointSpan.Start;
length = pCodeSpan[0].iEndLine > pCodeSpan[0].iStartLine ? initialBreakpointSpan.Length : 0;
}
}
// NOTE(cyrusn): we need to wait here because ValidateBreakpointLocation is
// synchronous. In the future, it would be nice for the debugger to provide
// an async entry point for this.
var breakpoint = _breakpointService.ResolveBreakpointAsync(document, new CodeAnalysis.Text.TextSpan(point.Position, length), cancellationToken).WaitAndGetResult(cancellationToken);
if (breakpoint == null)
{
// There should *not* be a breakpoint here. E_FAIL to let the debugger know
// that.
return(VSConstants.E_FAIL);
}
if (breakpoint.IsLineBreakpoint)
{
// Let the debugger take care of this. They'll put a line breakpoint
// here. This is useful for when the user does something like put a
// breakpoint in inactive code. We want to allow this as they might
// just have different defines during editing versus debugging.
// TODO(cyrusn): Do we need to set the pCodeSpan in this case?
return(VSConstants.E_NOTIMPL);
}
// There should be a breakpoint at the location passed back.
if (pCodeSpan != null && pCodeSpan.Length > 0)
{
pCodeSpan[0] = breakpoint.TextSpan.ToSnapshotSpan(snapshot).ToVsTextSpan();
}
return(VSConstants.S_OK);
}
}
return(VSConstants.E_NOTIMPL);
}
