public void OnFileChanged(TrackedFileEventArgs file)
{
if (CancellationToken.IsCancellationRequested)
{
return;
}
var filePath = file.Path;
ICancellableTask task = null;
// Check if we have an outstanding line count task. If we don't, kick one off
lock (OutstandingLineCounts)
{
if (!OutstandingLineCounts.ContainsKey(filePath))
{
// kick off and add line count task
task = CancellableTaskRunner.Run(async token =>
{
await CalculateLineCount(filePath, token);
}, onThreadPoolThread: true);
OutstandingLineCounts.Add(filePath, task);
}
}
task?.Task.ContinueWith(t =>
{
if (t.IsFaulted)
{
OnLineCountFailed?.Invoke(new LineCountFailedEventArgs(filePath, t.Exception));
}
});
}
public void OnFileRemoved(TrackedFileEventArgs file)
{
var filePath = file.Path;
// Cancel an outstanding line count task for this file, if one exists
lock (OutstandingLineCounts)
{
if (OutstandingLineCounts.TryGetValue(filePath, out var task))
{
task.Cancel();
}
}
lock (PathLineCounts)
{
// NOTE: if the key doesn't exist, the method will return null,
// not throw an exception, per method documentation
PathLineCounts.Remove(filePath);
}
}
protected async Task CalculateLineCount(string filePath, CancellationToken taskCancellationToken)
{
if (IsCancellationRequested())
{
return;
}
try
{
var lineCount = await LineCounter.CountLinesAsync(filePath, taskCancellationToken);
if (IsCancellationRequested())
{
return;
}
var result = AddOrUpdateLineCount(filePath, lineCount);
if (result.previous == null)
{
OnLineCountCreated?.Invoke(new LineCountCreatedEventArgs(filePath, result.current));
}
else
{
OnLineCountUpdated?.Invoke(new LineCountUpdatedEventArgs(filePath, result.current, result.previous));
}
}
finally
{
lock (OutstandingLineCounts)
{
OutstandingLineCounts.Remove(filePath);
}
}
bool IsCancellationRequested() => CancellationToken.IsCancellationRequested ||
taskCancellationToken.IsCancellationRequested;
}
