private async Task ProcessBrowsePromptWorker(IRSessionInteraction inter)
{
var frames = await Session.TracebackAsync();
// If there's .doTrace(rtvs:::breakpoint) anywhere on the stack, we're inside the internal machinery
// that triggered Browse> prompt when hitting a breakpoint. We need to step out of it until we're
// back at the frame where the breakpoint was actually set, so that those internal frames do not show
// on the call stack, and further stepping does not try to step through them.
// Since browserSetDebug-based step out is not reliable in the presence of loops, we'll just keep
// stepping over with "n" until we're all the way out. Every step will trigger a new prompt, and
// we will come back to this method again.
var doTraceFrame = frames.FirstOrDefault(frame => IsDoTrace(frame));
if (doTraceFrame != null)
{
await inter.RespondAsync(Invariant($"n\n"));
return;
}
IReadOnlyCollection <RBreakpoint> breakpointsHit = null;
var lastFrame = frames.LastOrDefault();
if (lastFrame != null)
{
// Report breakpoints first, so that by the time step completion is reported, all actions associated
// with breakpoints (e.g. printing messages for tracepoints) have already been completed.
if (lastFrame.FileName != null && lastFrame.LineNumber != null)
{
var location = new RSourceLocation(lastFrame.FileName, lastFrame.LineNumber.Value);
RBreakpoint bp;
if (_breakpoints.TryGetValue(location, out bp))
{
bp.RaiseBreakpointHit();
breakpointsHit = Enumerable.Repeat(bp, bp.UseCount).ToArray();
}
}
}
bool isStepCompleted = false;
if (_stepTcs != null)
{
var stepTcs = _stepTcs;
_stepTcs = null;
stepTcs.TrySetResult(breakpointsHit == null || breakpointsHit.Count == 0);
isStepCompleted = true;
}
EventHandler <RBrowseEventArgs> browse;
lock (_browseLock) {
browse = _browse;
}
var eventArgs = new RBrowseEventArgs(inter, isStepCompleted, breakpointsHit);
_currentBrowseEventArgs = eventArgs;
browse?.Invoke(this, eventArgs);
}
public async Task <IRBreakpoint> CreateBreakpointAsync(RSourceLocation location, CancellationToken cancellationToken = default(CancellationToken))
{
ThrowIfDisposed();
await TaskUtilities.SwitchToBackgroundThread();
await InitializeAsync(cancellationToken);
RBreakpoint bp;
if (!_breakpoints.TryGetValue(location, out bp))
{
bp = new RBreakpoint(this, location);
_breakpoints.Add(location, bp);
}
await bp.SetBreakpointAsync(cancellationToken);
return(bp);
}
internal RBreakpoint(RExecutionTracer tracer, RSourceLocation location)
{
_tracer = tracer;
Location = location;
}