protected virtual void OnResultsReady(BackgroundParserResultsReadyEventArgs args)
{
using (SynchronizeMainThreadState())
{
ResultsReady?.Invoke(this, args);
}
}
private void OnResultsReady(object sender, BackgroundParserResultsReadyEventArgs args)
{
_dispatcher.AssertBackgroundThread();
// Jump back to UI thread to notify structure changes.
Task.Factory.StartNew(OnDocumentStructureChanged, args, CancellationToken.None, TaskCreationOptions.None, _dispatcher.ForegroundScheduler);
}
public async Task GetLatestCodeDocumentAsync_NoPendingChangesReturnsImmediately()
{
// Arrange
var documentTracker = CreateDocumentTracker();
using (var parser = new DefaultVisualStudioRazorParser(
Dispatcher,
documentTracker,
ProjectEngineFactory,
new DefaultErrorReporter(),
Mock.Of <VisualStudioCompletionBroker>()))
{
var latestChange = new SourceChange(0, 0, string.Empty);
var latestSnapshot = documentTracker.TextBuffer.CurrentSnapshot;
parser._latestChangeReference = new BackgroundParser.ChangeReference(latestChange, latestSnapshot);
var codeDocument = TestRazorCodeDocument.CreateEmpty();
codeDocument.SetSyntaxTree(RazorSyntaxTree.Parse(TestRazorSourceDocument.Create()));
var args = new BackgroundParserResultsReadyEventArgs(
parser._latestChangeReference,
codeDocument);
parser.OnDocumentStructureChanged(args);
// Act - 1
var getLatestCodeDocumentTask = parser.GetLatestCodeDocumentAsync();
// Assert - 1
Assert.True(getLatestCodeDocumentTask.IsCompleted);
// Act - 2
var latestCodeDocument = await getLatestCodeDocumentTask;
// Assert - 2
Assert.Same(latestCodeDocument, codeDocument);
}
}
public void OnDocumentStructureChanged_FiresForLatestTextBufferEdit()
{
// Arrange
var documentTracker = CreateDocumentTracker();
using (var parser = new DefaultVisualStudioRazorParser(
Dispatcher,
documentTracker,
ProjectEngineFactory,
new DefaultErrorReporter(),
Mock.Of <VisualStudioCompletionBroker>()))
{
var called = false;
parser.DocumentStructureChanged += (sender, e) => called = true;
var latestChange = new SourceChange(0, 0, string.Empty);
var latestSnapshot = documentTracker.TextBuffer.CurrentSnapshot;
parser._latestChangeReference = new BackgroundParser.ChangeReference(latestChange, latestSnapshot);
var codeDocument = TestRazorCodeDocument.CreateEmpty();
codeDocument.SetSyntaxTree(RazorSyntaxTree.Parse(TestRazorSourceDocument.Create()));
var args = new BackgroundParserResultsReadyEventArgs(
parser._latestChangeReference,
codeDocument);
// Act
parser.OnDocumentStructureChanged(args);
// Assert
Assert.True(called);
}
}
public void GetLatestCodeDocumentAsync_MultipleCallsWithPendingChangesMemoizesReturnedTasks()
{
// Arrange
var documentTracker = CreateDocumentTracker();
using (var parser = new DefaultVisualStudioRazorParser(
Dispatcher,
documentTracker,
ProjectEngineFactory,
new DefaultErrorReporter(),
Mock.Of <VisualStudioCompletionBroker>()))
{
var latestChange = new SourceChange(0, 0, string.Empty);
var latestSnapshot = documentTracker.TextBuffer.CurrentSnapshot;
parser._latestChangeReference = new BackgroundParser.ChangeReference(latestChange, latestSnapshot);
var codeDocument = TestRazorCodeDocument.CreateEmpty();
codeDocument.SetSyntaxTree(RazorSyntaxTree.Parse(TestRazorSourceDocument.Create()));
var args = new BackgroundParserResultsReadyEventArgs(
parser._latestChangeReference,
codeDocument);
// Act
var getLatestCodeDocumentTask1 = parser.GetLatestCodeDocumentAsync();
var getLatestCodeDocumentTask2 = parser.GetLatestCodeDocumentAsync();
// Assert
Assert.Same(getLatestCodeDocumentTask1, getLatestCodeDocumentTask2);
}
}
// Internal for testing
internal void OnResultsReady(object sender, BackgroundParserResultsReadyEventArgs args)
{
_dispatcher.AssertBackgroundThread();
UpdateParserState(args.CodeDocument, args.ChangeReference.Snapshot);
// Jump back to UI thread to notify structure changes.
_ = Task.Factory.StartNew(OnDocumentStructureChanged, args, CancellationToken.None, TaskCreationOptions.None, _dispatcher.ForegroundScheduler);
}
// Internal for testing
#pragma warning disable VSTHRD100 // Avoid async void methods
internal async void OnResultsReady(object sender, BackgroundParserResultsReadyEventArgs args)
#pragma warning restore VSTHRD100 // Avoid async void methods
{
try
{
UpdateParserState(args.CodeDocument, args.ChangeReference.Snapshot);
// Jump back to UI thread to notify structure changes.
await _joinableTaskContext.Factory.SwitchToMainThreadAsync();
OnDocumentStructureChanged(args);
}
catch (Exception ex)
{
Debug.Fail("DefaultVisualStudioRazorParser.OnResultsReady threw exception:" +
Environment.NewLine + ex.Message + Environment.NewLine + "Stack trace:" + Environment.NewLine + ex.StackTrace);
}
}
public void ReturnParcel(BackgroundParserResultsReadyEventArgs args)
{
lock (_stateLock)
{
// Clear the current parcel cancellation source
if (_currentParcelCancelSource != null)
{
_currentParcelCancelSource.Dispose();
_currentParcelCancelSource = null;
}
// If there are things waiting to be parsed, just don't fire the event because we're already out of date
if (_changes.Any())
{
return;
}
}
ResultsReady?.Invoke(this, args);
}
public async Task GetLatestSyntaxTreeAsync_WaitsForParse()
{
// Arrange
var documentTracker = CreateDocumentTracker();
using (var parser = new DefaultVisualStudioRazorParser(
Dispatcher,
documentTracker,
ProjectEngineFactory,
new DefaultErrorReporter(),
Mock.Of <VisualStudioCompletionBroker>()))
{
var latestChange = new SourceChange(0, 0, string.Empty);
var latestSnapshot = documentTracker.TextBuffer.CurrentSnapshot;
parser._latestChangeReference = new BackgroundParser.ChangeReference(latestChange, latestSnapshot);
var codeDocument = TestRazorCodeDocument.CreateEmpty();
var syntaxTree = RazorSyntaxTree.Parse(TestRazorSourceDocument.Create());
codeDocument.SetSyntaxTree(syntaxTree);
var args = new BackgroundParserResultsReadyEventArgs(
parser._latestChangeReference,
codeDocument);
// Act - 1
var getLatestSyntaxTreeTask = parser.GetLatestSyntaxTreeAsync(StringTextSnapshot.Empty);
// Assert - 1
Assert.False(getLatestSyntaxTreeTask.IsCompleted);
// Act - 2
await Task.Run(() => parser.OnResultsReady(sender: null, args));
// Assert - 2
Assert.True(getLatestSyntaxTreeTask.IsCompleted);
// Act - 3
var latestSyntaxTree = await getLatestSyntaxTreeTask;
// Assert - 3
Assert.Same(latestSyntaxTree, syntaxTree);
}
}
public async Task GetLatestCodeDocumentAsync_ParserDisposed_ReturnsImmediately()
{
// Arrange
var documentTracker = CreateDocumentTracker();
var codeDocument = TestRazorCodeDocument.CreateEmpty();
var syntaxTree = RazorSyntaxTree.Parse(TestRazorSourceDocument.Create());
DefaultVisualStudioRazorParser parser;
codeDocument.SetSyntaxTree(syntaxTree);
using (parser = new DefaultVisualStudioRazorParser(
JoinableTaskContext,
documentTracker,
ProjectEngineFactory,
new DefaultErrorReporter(),
Mock.Of <VisualStudioCompletionBroker>(MockBehavior.Strict)))
{
var latestChange = new SourceChange(0, 0, string.Empty);
var latestSnapshot = documentTracker.TextBuffer.CurrentSnapshot;
parser._latestChangeReference = new BackgroundParser.ChangeReference(latestChange, latestSnapshot);
var args = new BackgroundParserResultsReadyEventArgs(
parser._latestChangeReference,
codeDocument);
// Initialize the document with some content so we have a syntax tree to return.
await Task.Run(() => parser.OnResultsReady(sender: null, args));
}
var newerSnapshot = new StringTextSnapshot("Newer", versionNumber: 1337);
// Act - 1
var getLatestCodeDocumentTask = parser.GetLatestCodeDocumentAsync(newerSnapshot);
// Assert - 1
Assert.True(getLatestCodeDocumentTask.IsCompleted);
// Act - 2
var latestCodeDocument = await getLatestCodeDocumentTask;
// Assert - 2
Assert.Same(latestCodeDocument, codeDocument);
}
public void OnDocumentStructureChanged_FiresForOnlyLatestTextBufferReparseEdit()
{
// Arrange
var documentTracker = CreateDocumentTracker();
using (var parser = new DefaultVisualStudioRazorParser(
Dispatcher,
documentTracker,
ProjectEngineFactory,
new DefaultErrorReporter(),
Mock.Of <VisualStudioCompletionBroker>()))
{
var called = false;
parser.DocumentStructureChanged += (sender, e) => called = true;
var latestSnapshot = documentTracker.TextBuffer.CurrentSnapshot;
parser._latestChangeReference = new BackgroundParser.ChangeReference(null, latestSnapshot);
var codeDocument = TestRazorCodeDocument.CreateEmpty();
codeDocument.SetSyntaxTree(RazorSyntaxTree.Parse(TestRazorSourceDocument.Create()));
var badArgs = new BackgroundParserResultsReadyEventArgs(
// This is a different reparse edit, shouldn't be fired for this call
new BackgroundParser.ChangeReference(null, latestSnapshot),
codeDocument);
var goodArgs = new BackgroundParserResultsReadyEventArgs(
parser._latestChangeReference,
codeDocument);
// Act - 1
parser.OnDocumentStructureChanged(badArgs);
// Assert - 1
Assert.False(called);
// Act - 2
parser.OnDocumentStructureChanged(goodArgs);
// Assert - 2
Assert.True(called);
}
}
public void OnDocumentStructureChanged_IgnoresEditsThatAreOld()
{
// Arrange
using (var parser = new DefaultVisualStudioRazorParser(
Dispatcher,
CreateDocumentTracker(),
ProjectEngineFactory,
new DefaultErrorReporter(),
Mock.Of <VisualStudioCompletionBroker>()))
{
var called = false;
parser.DocumentStructureChanged += (sender, e) => called = true;
parser._latestChangeReference = new BackgroundParser.ChangeReference(null, new StringTextSnapshot(string.Empty));
var args = new BackgroundParserResultsReadyEventArgs(
new BackgroundParser.ChangeReference(new SourceChange(0, 0, string.Empty), new StringTextSnapshot(string.Empty)),
TestRazorCodeDocument.CreateEmpty());
// Act
parser.OnDocumentStructureChanged(args);
// Assert
Assert.False(called);
}
}
// **** BACKGROUND THREAD ****
private void WorkerLoop()
{
try
{
EnsureOnThread();
while (!_shutdownToken.IsCancellationRequested)
{
// Grab the parcel of work to do
var parcel = _main.GetParcel();
if (parcel.Changes.Any())
{
try
{
BackgroundParserResultsReadyEventArgs args = null;
using (var linkedCancel = CancellationTokenSource.CreateLinkedTokenSource(_shutdownToken, parcel.CancelToken))
{
if (!linkedCancel.IsCancellationRequested)
{
// Collect ALL changes
List <ChangeReference> allChanges;
if (_previouslyDiscarded != null)
{
allChanges = Enumerable.Concat(_previouslyDiscarded, parcel.Changes).ToList();
}
else
{
allChanges = parcel.Changes.ToList();
}
var finalChange = allChanges.Last();
var results = ParseChange(finalChange.Snapshot, linkedCancel.Token);
if (results != null && !linkedCancel.IsCancellationRequested)
{
// Clear discarded changes list
_previouslyDiscarded = null;
_currentSyntaxTree = results.GetSyntaxTree();
// Build Arguments
args = new BackgroundParserResultsReadyEventArgs(finalChange, results);
}
else
{
// Parse completed but we were cancelled in the mean time. Add these to the discarded changes set
_previouslyDiscarded = allChanges;
}
}
}
if (args != null)
{
_main.ReturnParcel(args);
}
}
catch (OperationCanceledException)
{
}
}
else
{
Thread.Yield();
}
}
}
catch (OperationCanceledException)
{
// Do nothing. Just shut down.
}
finally
{
// Clean up main thread resources
_main.Dispose();
}
}
