Avoid UI state manipulation on background thread #68507
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sharwell
commented
Jun 9, 2023
| @@ -816,7 +816,7 @@ private async Task CommitCoreAsync(IUIThreadOperationContext operationContext, b | |||
| var eventName = previewChanges ? FunctionId.Rename_CommitCoreWithPreview : FunctionId.Rename_CommitCore; | |||
| using (Logger.LogBlock(eventName, KeyValueLogMessage.Create(LogType.UserAction), cancellationToken)) | |||
| { | |||
| var info = await _conflictResolutionTask.JoinAsync(cancellationToken).ConfigureAwait(false); | |||
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📝 This ConfigureAwait(false) was allowing the _dismissed field to be set from a background thread. Since RenameService.ActiveSession is cleared after _dismissed is set, it was allowing a UI thread check here to proceed between the point where _dismissed was set and the point where ActiveSession was cleared:
sharwell
commented
Jun 9, 2023
| // Note: this entire sequence of steps is not cancellable. We must perform it all to get back to a correct | ||
| // state for all the editors the user is interacting with. | ||
| var cancellationToken = CancellationToken.None; | ||
| await _threadingContext.JoinableTaskFactory.SwitchToMainThreadAsync(cancellationToken); |
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📝 This will now always NOP in practice, but the relocation of this switch to main thread adheres to JTF best practice. The code intentionally does not include an assertion.
akhera99
approved these changes
Jun 9, 2023
ghost
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Fixes AB#1833091