When cancelling an in-progress request, allow specifying the error returned to clients #33
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…turned to clients Currently, when implicitly cancelling requests because a document has been changed, we return an error response that indicates that the client cancelled the request because we translated all `CancellationError` to this response. The more accurate response is to indicate that the content has been modified, returning a `ContentModified` error. To do so, we need to make two changes: - `QueueBasedMessageHandler` needs to keep track of the reasons why it cancelled request handling tasks - The protocol requirement `QueueBasedMessageHandler.handle(request:id:reply)` needs to allow returning `CancellationError` instead of eagerly transforming it to a `ResponseError` in `RequestAndReply`. This is an API-breaking change. I haven’t found a great way to add a compatibility layer, so I propose that we need to have linked PRs in SourceKit-LSP and SwiftPM that need to be merged when we are updating the swift-tools-protocols version in the toolchain.
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… of `ResponseError` Update for the API changed in swiftlang/swift-tools-protocols#33.
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… of `ResponseError` Update for the API changed in swiftlang/swift-tools-protocols#33.
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… of `ResponseError` Update for the API changed in swiftlang/swift-tools-protocols#33.
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Currently, when implicitly cancelling requests because a document has been changed, we return an error response that indicates that the client cancelled the request because we translated all
CancellationErrorto this response. The more accurate response is to indicate that the content has been modified, returning aContentModifiederror.To do so, we need to make two changes:
QueueBasedMessageHandlerneeds to keep track of the reasons why it cancelled request handling tasksQueueBasedMessageHandler.handle(request:id:reply)needs to allow returningCancellationErrorinstead of eagerly transforming it to aResponseErrorinRequestAndReply. This is an API-breaking change. I haven’t found a great way to add a compatibility layer, so I propose that we need to have linked PRs in SourceKit-LSP and SwiftPM that need to be merged when we are updating the swift-tools-protocols version in the toolchain.This is a prerequisite to fixing swiftlang/sourcekit-lsp#2136 (comment).
PRs that need to be merged when this gets picked up in toolchain builds:
QueueBasedMessageHandler.handleto returnany Errorinstead ofResponseErrorsourcekit-lsp#2416QueueBasedMessageHandler.handleto returnany Errorinstead ofResponseErrorswift-package-manager#9557QueueBasedMessageHandler.handleto returnany Errorinstead ofResponseErrorswift-build#1003