tor-browser

The Tor Browser
git clone https://git.dasho.dev/tor-browser.git
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Promise.js (2167B)

      1 /* This Source Code Form is subject to the terms of the Mozilla Public
      2 * License, v. 2.0. If a copy of the MPL was not distributed with this
      3 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
      4 
      5 // Promise.prototype.finally proposal, stage 3.
      6 // Promise.prototype.finally ( onFinally )
      7 function Promise_finally(onFinally) {
      8  // Step 1.
      9  var promise = this;
     10 
     11  // Step 2.
     12  if (!IsObject(promise)) {
     13    ThrowTypeError(JSMSG_INCOMPATIBLE_PROTO, "Promise", "finally", "value");
     14  }
     15 
     16  // Step 3.
     17  var C = SpeciesConstructor(promise, GetBuiltinConstructor("Promise"));
     18 
     19  // Step 4.
     20  assert(IsConstructor(C), "SpeciesConstructor returns a constructor function");
     21 
     22  // Steps 5-6.
     23  var thenFinally, catchFinally;
     24  if (!IsCallable(onFinally)) {
     25    thenFinally = onFinally;
     26    catchFinally = onFinally;
     27  } else {
     28    // ThenFinally Function.
     29    // The parentheses prevent the infering of a function name.
     30    // prettier-ignore
     31    (thenFinally) = function(value) {
     32      // Steps 1-2 (implicit).
     33 
     34      // Step 3.
     35      var result = callContentFunction(onFinally, undefined);
     36 
     37      // Steps 4-5 (implicit).
     38 
     39      // Step 6.
     40      var promise = PromiseResolve(C, result);
     41 
     42      // Step 7.
     43      // FIXME: spec issue - "be equivalent to a function that" is not a defined spec term.
     44      // https://github.com/tc39/ecma262/issues/933
     45 
     46      // Step 8.
     47      return callContentFunction(promise.then, promise, function() {
     48        return value;
     49      });
     50    };
     51 
     52    // CatchFinally Function.
     53    // prettier-ignore
     54    (catchFinally) = function(reason) {
     55      // Steps 1-2 (implicit).
     56 
     57      // Step 3.
     58      var result = callContentFunction(onFinally, undefined);
     59 
     60      // Steps 4-5 (implicit).
     61 
     62      // Step 6.
     63      var promise = PromiseResolve(C, result);
     64 
     65      // Step 7.
     66      // FIXME: spec issue - "be equivalent to a function that" is not a defined spec term.
     67      // https://github.com/tc39/ecma262/issues/933
     68 
     69      // Step 8.
     70      return callContentFunction(promise.then, promise, function() {
     71        throw reason;
     72      });
     73    };
     74  }
     75 
     76  // Step 7.
     77  return callContentFunction(promise.then, promise, thenFinally, catchFinally);
     78 }