• caitpotter88's avatar
    [promise] Make Promise.all match spec, and always respect [[AlreadyResolved]] · 7459d8ce
    caitpotter88 authored
    Testing the promise status is not enough to ensure that resolve functions are
    called only once.
    
    This change adds a similar version of the [[AlreadyResolved]] slot to the
    Promise.all resolve element function, and also ensures that [[AlreadyResolved]]
    is respected in the Promise executor, and when resolving thenables. This means
    replacing PromiseReject() shortcuts with promiseCapability.reject(), which has
    an [[AlreadyResolved]] record in a context slot.
    
    Also ensures that changes to the list accumulator in Promise.all() is not observable
    via accessors installed in the Array prototype chain, using the same mechanism used
    in several Array methods.
    
    Fixes the following Test262 tests:
    - built-ins/Promise/all/call-resolve-element-items.js
    - built-ins/Promise/all/call-resolve-element.js
    - built-ins/Promise/all/call-resolve-element-after-return.js
    - built-ins/Promise/all/same-reject-function.js
    - built-ins/Promise/all/resolve-from-same-thenable.js
    - built-ins/Promise/all/resolve-before-loop-exit.js
    - built-ins/Promise/all/resolve-before-loop-exit-from-same.js
    - built-ins/Promise/exception-after-resolve-in-executor.js
    - built-ins/Promise/exception-after-resolve-in-thenable-job.js
    - built-ins/Promise/all/does-not-invoke-array-setters.js
    
    BUG=v8:4633
    LOG=N
    R=littledan@chromium.org, cbruni@chromium.org
    
    Review URL: https://codereview.chromium.org/1534813005
    
    Cr-Commit-Position: refs/heads/master@{#33163}
    7459d8ce
promise.js 14.3 KB