add tests for proposed faster-promise-try change - #5072
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https://bugs.webkit.org/show_bug.cgi?id=321890 rdar://185064567 Reviewed by Sosuke Suzuki. Test262 is updated[1] to include the latest spec change proposal for Promise.try[2], which uses PromiseResolve instead of a promise created by NewPromiseCapability. This simplifies our Promise.try implementation since we can just use @promiseResolve and @promisereject helpers instead. Also this removes the reference to @newPromiseCapability in JSC code. So we drop PromiseOperations.js and its JS builtins, and replace @newPromiseCapability with C++ version for remaining WebCore users. WebCore users can be replaced by using normal Promise + first-resolving handler. This is fixed in a subsequent change. [1]: tc39/test262#5072 [2]: tc39/ecma262#3883 * JSTests/test262/expectations.yaml: * Source/JavaScriptCore/CMakeLists.txt: * Source/JavaScriptCore/DerivedSources-input.xcfilelist: * Source/JavaScriptCore/DerivedSources.make: * Source/JavaScriptCore/JavaScriptCore.xcodeproj/project.pbxproj: * Source/JavaScriptCore/builtins/BuiltinNames.h: * Source/JavaScriptCore/builtins/PromiseConstructor.js: (try): * Source/JavaScriptCore/builtins/PromiseOperations.js: Removed. * Source/JavaScriptCore/bytecode/LinkTimeConstant.h: * Source/JavaScriptCore/runtime/JSGlobalObject.cpp: (JSC::JSC_DEFINE_HOST_FUNCTION): (JSC::JSGlobalObject::init): Canonical link: https://commits.webkit.org/319276@main
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tc39/ecma262#3883 changed `Promise.try` to end with `Return ? PromiseResolve(ctor, ! status)`, instead of creating a capability up front and resolving through it. A promise returned from the callback is now passed through rather than wrapped, and the capability is only created on the abrupt-completion path. test262 pins this in `built-ins/Promise/try/avoids-wrap.js` and `avoids-wrap-for-subclass.js` (tc39/test262#5072). No engine has shipped the change yet, so `getPolyfill` probes for the older wrapping behavior and falls back to the implementation.
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tc39/ecma262#3883 changed `Promise.try` to end with `Return ? PromiseResolve(ctor, ! status)`, instead of creating a capability up front and resolving through it. A promise returned from the callback is now passed through rather than wrapped, and the capability is only created on the abrupt-completion path. test262 pins this in `built-ins/Promise/try/avoids-wrap.js` and `avoids-wrap-for-subclass.js` (tc39/test262#5072). No engine has shipped the change yet, so `getPolyfill` probes for the older wrapping behavior and falls back to the implementation.
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Tests for tc39/ecma262#3883.
Also includes a test that
Subclass.tryuses the subclass to wrap the rejection. The linked PR doesn't change that but it's untested currently. I can split it into its own PR if you'd like.None of the existing tests are affected by that PR.