Preliminary promise implementation.

test/mjsunit/harmony/promises.js

+// Copyright 2013 the V8 project authors. All rights reserved.
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+//       notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+//       copyright notice, this list of conditions and the following
+//       disclaimer in the documentation and/or other materials provided
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Flags: --harmony-promises --harmony-observation
+
+var asyncAssertsExpected = 0;
+
+function assertAsyncRan() { ++asyncAssertsExpected }
+
+function assertAsync(b, s) {
+  assert(b, s)
+  --asyncAssertsExpected
+}
+
+function assertAsyncDone() {
+  var previous = asyncAssertsExpected
+  var dummy = {}
+  Object.observe(dummy,
+    function() {
+      if (asyncAssertsExpected < previous)
+        assertAsyncDone()  // Progress, queue check again
+      else
+        assertEqual(0, asyncAssertsExpected)
+    }
+  )
+  dummy.dummy = dummy
+}
+
+
+(function() {
+  Promise.resolved(5);
+  Promise.resolved(5).when(undefined, assertUnreachable).when(
+    function(x) { assertAsync(x === undefined, "resolved/when-nohandler") },
+    assertUnreachable
+  )
+  assertAsyncRan()
+})();
+
+(function() {
+  Promise.rejected(5).when(assertUnreachable, undefined).when(
+    function(x) { assertAsync(x === undefined, "rejected/when-nohandler") },
+    assertUnreachable
+  )
+  assertAsyncRan()
+})();
+
+(function() {
+  Promise.resolved(5).then(undefined, assertUnreachable).when(
+    function(x) { assertAsync(x === undefined, "resolved/then-nohandler") },
+    assertUnreachable
+  )
+  assertAsyncRan()
+})();
+
+(function() {
+  Promise.rejected(5).then(assertUnreachable, undefined).when(
+    function(x) { assertAsync(x === undefined, "rejected/then-nohandler") },
+    assertUnreachable
+  )
+  assertAsyncRan()
+})();
+
+(function() {
+  var p1 = Promise.resolved(5)
+  var p2 = Promise.resolved(p1)
+  var p3 = Promise.resolved(p2)
+  p3.when(function(x) { assertAsync(x === p2, "resolved/when") }, assertUnreachable)
+  assertAsyncRan()
+})();
+
+(function() {
+  var p1 = Promise.resolved(5)
+  var p2 = Promise.resolved(p1)
+  var p3 = Promise.resolved(p2)
+  p3.then(function(x) { assertAsync(x === 5, "resolved/then") }, assertUnreachable)
+  assertAsyncRan()
+})();
+
+(function() {
+  var p1 = Promise.rejected(5)
+  var p2 = Promise.resolved(p1)
+  var p3 = Promise.resolved(p2)
+  p3.when(function(x) { assertAsync(x === p2, "rejected/when") }, assertUnreachable)
+  assertAsyncRan()
+})();
+
+(function() {
+  var p1 = Promise.rejected(5)
+  var p2 = Promise.resolved(p1)
+  var p3 = Promise.resolved(p2)
+  p3.then(assertUnreachable, function(x) { assertAsync(x === 5, "rejected/then") })
+  assertAsyncRan()
+})();
+
+(function() {
+  var p1 = Promise.resolved(5)
+  var p2 = Promise.resolved(p1)
+  var p3 = Promise.resolved(p2)
+  p3.when(function(x) { return x }, assertUnreachable)
+    .when(function(x) { assertAsync(x === p1, "resolved/when/when") }, assertUnreachable)
+  assertAsyncRan()
+})();
+
+(function() {
+  var p1 = Promise.resolved(5)
+  var p2 = Promise.resolved(p1)
+  var p3 = Promise.resolved(p2)
+  p3.when(function(x) { return x }, assertUnreachable)
+    .then(function(x) { assertAsync(x === 5, "resolved/when/then") }, assertUnreachable)
+  assertAsyncRan()
+})();
+
+(function() {
+  var p1 = Promise.resolved(5)
+  var p2 = Promise.resolved(p1)
+  var p3 = Promise.resolved(p2)
+  p3.when(function(x) { return 6 }, assertUnreachable)
+    .when(function(x) { assertAsync(x === 6, "resolved/when/when2") }, assertUnreachable)
+  assertAsyncRan()
+})();
+
+(function() {
+  var p1 = Promise.resolved(5)
+  var p2 = Promise.resolved(p1)
+  var p3 = Promise.resolved(p2)
+  p3.when(function(x) { return 6 }, assertUnreachable)
+    .then(function(x) { assertAsync(x === 6, "resolved/when/then2") }, assertUnreachable)
+  assertAsyncRan()
+})();
+
+(function() {
+  var p1 = Promise.resolved(5)
+  var p2 = Promise.resolved(p1)
+  var p3 = Promise.resolved(p2)
+  p3.then(function(x) { return x + 1 }, assertUnreachable)
+    .when(function(x) { assertAsync(x === 6, "resolved/then/when") }, assertUnreachable)
+  assertAsyncRan()
+})();
+
+(function() {
+  var p1 = Promise.resolved(5)
+  var p2 = Promise.resolved(p1)
+  var p3 = Promise.resolved(p2)
+  p3.then(function(x) { return x + 1 }, assertUnreachable)
+    .then(function(x) { assertAsync(x === 6, "resolved/then/then") }, assertUnreachable)
+  assertAsyncRan()
+})();
+
+(function() {
+  var p1 = Promise.resolved(5)
+  var p2 = Promise.resolved(p1)
+  var p3 = Promise.resolved(p2)
+  p3.then(function(x) { return Promise.resolved(x + 1) }, assertUnreachable)
+    .when(function(x) { assertAsync(x === 6, "resolved/then/when2") }, assertUnreachable)
+  assertAsyncRan()
+})();
+
+(function() {
+  var p1 = Promise.resolved(5)
+  var p2 = Promise.resolved(p1)
+  var p3 = Promise.resolved(p2)
+  p3.then(function(x) { return Promise.resolved(x + 1) }, assertUnreachable)
+    .then(function(x) { assertAsync(x === 6, "resolved/then/then2") }, assertUnreachable)
+  assertAsyncRan()
+})();
+
+(function() {
+  var p1 = Promise.resolved(5)
+  var p2 = Promise.resolved(p1)
+  var p3 = Promise.resolved(p2)
+  p3.when(function(x) { throw 6 }, assertUnreachable)
+    .when(assertUnreachable, function(x) { assertAsync(x === 6, "resolved/when-throw/when") })
+  assertAsyncRan()
+})();
+
+(function() {
+  var p1 = Promise.resolved(5)
+  var p2 = Promise.resolved(p1)
+  var p3 = Promise.resolved(p2)
+  p3.when(function(x) { throw 6 }, assertUnreachable)
+    .then(assertUnreachable, function(x) { assertAsync(x === 6, "resolved/when-throw/then") })
+  assertAsyncRan()
+})();
+
+(function() {
+  var p1 = Promise.resolved(5)
+  var p2 = Promise.resolved(p1)
+  var p3 = Promise.resolved(p2)
+  p3.then(function(x) { throw 6 }, assertUnreachable)
+    .when(assertUnreachable, function(x) { assertAsync(x === 6, "resolved/then-throw/when") })
+  assertAsyncRan()
+})();
+
+(function() {
+  var p1 = Promise.resolved(5)
+  var p2 = Promise.resolved(p1)
+  var p3 = Promise.resolved(p2)
+  p3.then(function(x) { throw 6 }, assertUnreachable)
+    .then(assertUnreachable, function(x) { assertAsync(x === 6, "resolved/then-throw/then") })
+  assertAsyncRan()
+})();
+
+(function() {
+  var p1 = Promise.resolved(5)
+  var p2 = {then: function(onResolve, onReject) { onResolve(p1) }}
+  var p3 = Promise.resolved(p2)
+  p3.when(function(x) { assertAsync(x === p2, "resolved/thenable/when") }, assertUnreachable)
+  assertAsyncRan()
+})();
+
+(function() {
+  var p1 = Promise.resolved(5)
+  var p2 = {then: function(onResolve, onReject) { onResolve(p1) }}
+  var p3 = Promise.resolved(p2)
+  p3.then(function(x) { assertAsync(x === 5, "resolved/thenable/then") }, assertUnreachable)
+  assertAsyncRan()
+})();
+
+(function() {
+  var p1 = Promise.rejected(5)
+  var p2 = {then: function(onResolve, onReject) { onResolve(p1) }}
+  var p3 = Promise.resolved(p2)
+  p3.when(function(x) { assertAsync(x === p2, "rejected/thenable/when") }, assertUnreachable)
+  assertAsyncRan()
+})();
+
+(function() {
+  var p1 = Promise.rejected(5)
+  var p2 = {then: function(onResolve, onReject) { onResolve(p1) }}
+  var p3 = Promise.resolved(p2)
+  p3.then(assertUnreachable, function(x) { assertAsync(x === 5, "rejected/thenable/then") })
+  assertAsyncRan()
+})();
+
+(function() {
+  var deferred = Promise.deferred()
+  var p1 = deferred.promise
+  var p2 = Promise.resolved(p1)
+  var p3 = Promise.resolved(p2)
+  p3.when(function(x) { assertAsync(x === p2, "when/resolve") }, assertUnreachable)
+  deferred.resolve(5)
+  assertAsyncRan()
+})();
+
+(function() {
+  var deferred = Promise.deferred()
+  var p1 = deferred.promise
+  var p2 = Promise.resolved(p1)
+  var p3 = Promise.resolved(p2)
+  p3.then(function(x) { assertAsync(x === 5, "then/resolve") }, assertUnreachable)
+  deferred.resolve(5)
+  assertAsyncRan()
+})();
+
+(function() {
+  var deferred = Promise.deferred()
+  var p1 = deferred.promise
+  var p2 = Promise.resolved(p1)
+  var p3 = Promise.resolved(p2)
+  p3.when(function(x) { assertAsync(x === p2, "when/reject") }, assertUnreachable)
+  deferred.reject(5)
+  assertAsyncRan()
+})();
+
+(function() {
+  var deferred = Promise.deferred()
+  var p1 = deferred.promise
+  var p2 = Promise.resolved(p1)
+  var p3 = Promise.resolved(p2)
+  p3.then(assertUnreachable, function(x) { assertAsync(x === 5, "then/reject") })
+  deferred.reject(5)
+  assertAsyncRan()
+})();
+
+(function() {
+  var deferred = Promise.deferred()
+  var p1 = deferred.promise
+  var p2 = {then: function(onResolve, onReject) { onResolve(p1) }}
+  var p3 = Promise.resolved(p2)
+  p3.when(function(x) { assertAsync(x === p2, "when/resolve/thenable") }, assertUnreachable)
+  deferred.resolve(5)
+  assertAsyncRan()
+})();
+
+(function() {
+  var deferred = Promise.deferred()
+  var p1 = deferred.promise
+  var p2 = {then: function(onResolve, onReject) { onResolve(p1) }}
+  var p3 = Promise.resolved(p2)
+  p3.then(function(x) { assertAsync(x === 5, "then/resolve/thenable") }, assertUnreachable)
+  deferred.resolve(5)
+  assertAsyncRan()
+})();
+
+(function() {
+  var deferred = Promise.deferred()
+  var p1 = deferred.promise
+  var p2 = {then: function(onResolve, onReject) { onResolve(p1) }}
+  var p3 = Promise.resolved(p2)
+  p3.when(function(x) { assertAsync(x === p2, "when/reject/thenable") }, assertUnreachable)
+  deferred.reject(5)
+  assertAsyncRan()
+})();
+
+(function() {
+  var deferred = Promise.deferred()
+  var p1 = deferred.promise
+  var p2 = {then: function(onResolve, onReject) { onResolve(p1) }}
+  var p3 = Promise.resolved(p2)
+  p3.then(assertUnreachable, function(x) { assertAsync(x === 5, "then/reject/thenable") })
+  deferred.reject(5)
+  assertAsyncRan()
+})();
+
+(function() {
+  var p1 = Promise.resolved(5)
+  var p2 = Promise.resolved(p1)
+  var deferred = Promise.deferred()
+  var p3 = deferred.promise
+  p3.when(function(x) { assertAsync(x === p2, "when/resolve2") }, assertUnreachable)
+  deferred.resolve(p2)
+  assertAsyncRan()
+})();
+
+(function() {
+  var p1 = Promise.resolved(5)
+  var p2 = Promise.resolved(p1)
+  var deferred = Promise.deferred()
+  var p3 = deferred.promise
+  p3.then(function(x) { assertAsync(x === 5, "then/resolve2") }, assertUnreachable)
+  deferred.resolve(p2)
+  assertAsyncRan()
+})();
+
+(function() {
+  var p1 = Promise.resolved(5)
+  var p2 = Promise.resolved(p1)
+  var deferred = Promise.deferred()
+  var p3 = deferred.promise
+  p3.when(assertUnreachable, function(x) { assertAsync(x === 5, "when/reject2") })
+  deferred.reject(5)
+  assertAsyncRan()
+})();
+
+(function() {
+  var p1 = Promise.resolved(5)
+  var p2 = Promise.resolved(p1)
+  var deferred = Promise.deferred()
+  var p3 = deferred.promise
+  p3.then(assertUnreachable, function(x) { assertAsync(x === 5, "then/reject2") })
+  deferred.reject(5)
+  assertAsyncRan()
+})();
+
+(function() {
+  var p1 = Promise.resolved(5)
+  var p2 = {then: function(onResolve, onReject) { onResolve(p1) }}
+  var deferred = Promise.deferred()
+  var p3 = deferred.promise
+  p3.when(function(x) { assertAsync(x === p2, "when/resolve/thenable2") }, assertUnreachable)
+  deferred.resolve(p2)
+  assertAsyncRan()
+})();
+
+(function() {
+  var p1 = Promise.resolved(5)
+  var p2 = {then: function(onResolve, onReject) { onResolve(p1) }}
+  var deferred = Promise.deferred()
+  var p3 = deferred.promise
+  p3.then(function(x) { assertAsync(x === 5, "then/resolve/thenable2") }, assertUnreachable)
+  deferred.resolve(p2)
+  assertAsyncRan()
+})();
+
+(function() {
+  var p1 = Promise.resolved(0)
+  var p2 = p1.when(function(x) { return p2 }, assertUnreachable)
+  p2.when(assertUnreachable,
+    function(r) { assertAsync(r instanceof TypeError, "cyclic/when") })
+  assertAsyncRan()
+})();
+
+(function() {
+  var p1 = Promise.resolved(0)
+  var p2 = p1.then(function(x) { return p2 }, assertUnreachable)
+  p2.when(assertUnreachable,
+    function(r) { assertAsync(r instanceof TypeError, "cyclic/then") })
+  assertAsyncRan()
+})();
+
+(function() {
+  var deferred = Promise.deferred()
+  var p = deferred.promise
+  deferred.resolve(p)
+  p.when(function(x) { assertAsync(x === p, "cyclic/deferred/when") }, assertUnreachable)
+  assertAsyncRan()
+})();
+
+(function() {
+  var deferred = Promise.deferred()
+  var p = deferred.promise
+  deferred.resolve(p)
+  p.then(assertUnreachable,
+    function(r) { assertAsync(r instanceof TypeError, "cyclic/deferred/then") })
+  assertAsyncRan()
+})();
+
+(function() {
+  var deferred1 = Promise.deferred()
+  var p1 = deferred1.promise
+  var deferred2 = Promise.deferred()
+  var p2 = deferred2.promise
+  var deferred3 = Promise.deferred()
+  var p3 = deferred3.promise
+  Promise.all([p1, p2, p3]).when(function(x) { assertAsync(x === undefined, "all/resolve") }, assertUnreachable)
+  deferred1.resolve(1)
+  deferred3.resolve(3)
+  deferred2.resolve(2)
+  assertAsyncRan()
+})();
+
+(function() {
+  var deferred = Promise.deferred()
+  var p1 = deferred.promise
+  var p2 = Promise.resolved(2)
+  var p3 = Promise.deferred().promise
+  Promise.all([p1, p2, p3]).when(assertUnreachable, assertUnreachable)
+  deferred.resolve(1)
+})();
+
+(function() {
+  var deferred1 = Promise.deferred()
+  var p1 = deferred1.promise
+  var deferred2 = Promise.deferred()
+  var p2 = deferred2.promise
+  var deferred3 = Promise.deferred()
+  var p3 = deferred3.promise
+  Promise.all([p1, p2, p3]).when(assertUnreachable, function(x) { assertAsync(x === 2, "all/reject") })
+  deferred1.resolve(1)
+  deferred3.resolve(3)
+  deferred2.reject(2)
+  assertAsyncRan()
+})();
+
+(function() {
+  var p1 = Promise.resolved(1)
+  var p2 = Promise.resolved(2)
+  var p3 = Promise.resolved(3)
+  Promise.one([p1, p2, p3]).when(function(x) { assertAsync(x === 1, "resolved/all") }, assertUnreachable)
+  assertAsyncRan()
+})();
+
+(function() {
+  var p1 = Promise.resolved(1)
+  var p2 = Promise.resolved(2)
+  var p3 = Promise.resolved(3)
+  Promise.one([0, p1, p2, p3]).when(function(x) { assertAsync(x === 0, "resolved-const/all") }, assertUnreachable)
+  assertAsyncRan()
+})();
+
+(function() {
+  var deferred1 = Promise.deferred()
+  var p1 = deferred1.promise
+  var deferred2 = Promise.deferred()
+  var p2 = deferred2.promise
+  var deferred3 = Promise.deferred()
+  var p3 = deferred3.promise
+  Promise.one([p1, p2, p3]).when(function(x) { assertAsync(x === 3, "one/resolve") }, assertUnreachable)
+  deferred3.resolve(3)
+  deferred1.resolve(1)
+  assertAsyncRan()
+})();
+
+(function() {
+  var deferred = Promise.deferred()
+  var p1 = deferred.promise
+  var p2 = Promise.resolved(2)
+  var p3 = Promise.deferred().promise
+  Promise.one([p1, p2, p3]).when(function(x) { assertAsync(x === 2, "resolved/one") }, assertUnreachable)
+  deferred.resolve(1)
+  assertAsyncRan()
+})();
+
+(function() {
+  var deferred1 = Promise.deferred()
+  var p1 = deferred1.promise
+  var deferred2 = Promise.deferred()
+  var p2 = deferred2.promise
+  var deferred3 = Promise.deferred()
+  var p3 = deferred3.promise
+  Promise.one([p1, p2, p3]).when(function(x) { assertAsync(x === 3, "one/resolve/reject") }, assertUnreachable)
+  deferred3.resolve(3)
+  deferred1.reject(1)
+  assertAsyncRan()
+})();
+
+(function() {
+  var deferred1 = Promise.deferred()
+  var p1 = deferred1.promise
+  var deferred2 = Promise.deferred()
+  var p2 = deferred2.promise
+  var deferred3 = Promise.deferred()
+  var p3 = deferred3.promise
+  Promise.one([p1, p2, p3]).when(assertUnreachable, function(x) { assertAsync(x === 3, "one/reject/resolve") })
+  deferred3.reject(3)
+  deferred1.resolve(1)
+  assertAsyncRan()
+})();
+
+(function() {
+  var log
+  function MyPromise(resolver) {
+    log += "n"
+    Promise.call(this,
+      function(resolve, reject) {
+        resolver(
+          function(x) { log += "x" + x; resolve(x) },
+          function(r) { log += "r" + r; reject(r) }
+        )
+      }
+    )
+  }
+
+  MyPromise.__proto__ = Promise
+  MyPromise.deferred = function() {
+    log += "d"
+    return this.__proto__.deferred.call(this)
+  }
+
+  MyPromise.prototype.__proto__ = Promise.prototype
+  MyPromise.prototype.when = function(resolve, reject) {
+    log += "w" 
+    return this.__proto__.__proto__.when.call(this, resolve, reject)
+  }
+
+  log = ""
+  var p1 = new MyPromise(function(resolve, reject) { resolve(1) })
+  var p2 = new MyPromise(function(resolve, reject) { reject(2) })
+  var d3 = MyPromise.deferred()
+  assertTrue(d3.promise instanceof MyPromise, "subclass/instance3")
+  assertTrue(log === "nx1nr2dn", "subclass/create")
+
+  log = ""
+  var p4 = MyPromise.resolved(4)
+  var p5 = MyPromise.rejected(5)
+  assertTrue(p4 instanceof MyPromise, "subclass/instance4")
+  assertTrue(p5 instanceof MyPromise, "subclass/instance5")
+  d3.resolve(3)
+  assertTrue(log === "nx4nr5x3", "subclass/resolve")
+
+  log = ""
+  var d6 = MyPromise.deferred()
+  d6.promise.when(function(x) { return new Promise(x) }).when(function() {})
+  d6.resolve(6)
+  assertTrue(log === "dnwnwnx6", "subclass/when")
+
+  log = ""
+  Promise.all([11, Promise.resolved(12), 13, MyPromise.resolved(14), 15, 16])
+  assertTrue(log === "nx14wn", "subclass/all/arg")
+
+  log = ""
+  MyPromise.all([21, Promise.resolved(22), 23, MyPromise.resolved(24), 25, 26])
+  assertTrue(log === "nx24dnnx21wndnwnnx23wnwnnx25wnnx26wn", "subclass/all/self")
+})();
+
+
+assertAsyncDone()