AsyncContext proposal integration (part 1)#12152
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andreubotella wants to merge 2 commits intowhatwg:mainfrom
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AsyncContext proposal integration (part 1)#12152andreubotella wants to merge 2 commits intowhatwg:mainfrom
andreubotella wants to merge 2 commits intowhatwg:mainfrom
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This PR updates HTML to integrate with the TC39 AsyncContext proposal, which allows storing state associated with an async flow of execution in JavaScript, and preserving it across different kinds of async continuations in both JS and the web platform. This PR does not yet handle events, since the exact behavior of those with AsyncContext is still pending to be fully decided. But it covers microtasks, timers, deferred script execution, focus/blur and others. This patch does not include any changes to the `error` and `unhandledrejection` event handling, as well as to `HostEnqueueFinalizationRegistryCleanupJob`. This relies on the assumption that the changes in tc39/proposal-async-context#148 and tc39/proposal-async-context#150 will be accepted. Otherwise, error contexts will need to be handled in HTML. This patch relies on PR [TODO] to define the `[PropagatesAsyncContext]` extended attribute in WebIDL.
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This PR updates WebIDL to add the `[PropagatesAsyncContext]` extended attribute. This is a part of the TC39 AsyncContext proposal, which allows storing state associated with an async flow of execution in JavaScript, and preserving it across different kinds of async continuations in both JS and the web platform. This `[PropagatesAsyncContext]` extended attribute can only be applied to callback function types in operation arguments. When set, the callback context will also store an Async Context Mapping, which the callback will run in. This allows a callback-taking operation to act like an async continuation, and propagate the state associated with the async flow of execution at the time that this operation is called to the callback. This patch relies on HTML's PR whatwg/html#12152 to define the "run with Async Context Mapping" operation. This operation must be defined in a web specs rather than in the TC39 proposal because it deals with throwing in spec algorithms, which is not a concept in the TC39 specs.
andreubotella
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This PR updates WebIDL to add the `[PropagatesAsyncContext]` extended attribute. This is a part of the TC39 AsyncContext proposal, which allows storing state associated with an async flow of execution in JavaScript, and preserving it across different kinds of async continuations in both JS and the web platform. This `[PropagatesAsyncContext]` extended attribute can only be applied to callback function types in operation arguments. When set, the callback context will also store an Async Context Mapping, which the callback will run in. This allows a callback-taking operation to act like an async continuation, and propagate the state associated with the async flow of execution at the time that this operation is called to the callback. This patch relies on HTML's PR whatwg/html#12152 to define the "run with Async Context Mapping" operation. This operation must be defined in a web specs rather than in the TC39 proposal because it deals with throwing in spec algorithms, which is not a concept in the TC39 specs.
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This PR updates HTML to integrate with the TC39 AsyncContext proposal, which allows storing state associated with an async flow of execution in JavaScript, and preserving it across different kinds of async continuations in both JS and the web platform.
This PR does not yet handle events, since the exact behavior of those with AsyncContext is still pending to be fully decided. But it covers microtasks, timers, deferred script execution, focus/blur and others.
This patch does not include any changes to the
errorandunhandledrejectionevent handling, as well as toHostEnqueueFinalizationRegistryCleanupJob. This relies on the assumption that the changes in tc39/proposal-async-context#148 and tc39/proposal-async-context#150 will be accepted. Otherwise, error contexts will need to be handled in HTML.This patch relies on PR whatwg/webidl#1568 to define the
[PropagatesAsyncContext]extended attribute in WebIDL.This PR is part of #10432.
(See WHATWG Working Mode: Changes for more details.)
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/scripting.html ( diff )
/timers-and-user-prompts.html ( diff )
/webappapis.html ( diff )