RSVP#resolve

browser/rsvp.amd.js

 define(
-  ["rsvp/events","rsvp/promise","rsvp/node","rsvp/all","rsvp/hash","rsvp/defer","rsvp/config","exports"],
-  function(__dependency1__, __dependency2__, __dependency3__, __dependency4__, __dependency5__, __dependency6__, __dependency7__, __exports__) {
+  ["rsvp/events","rsvp/promise","rsvp/node","rsvp/all","rsvp/hash","rsvp/defer","rsvp/config","rsvp/resolve","exports"],
+  function(__dependency1__, __dependency2__, __dependency3__, __dependency4__, __dependency5__, __dependency6__, __dependency7__, __dependency8__, __exports__) {
     "use strict";
     var EventTarget = __dependency1__.EventTarget;
     var Promise = __dependency2__.Promise;
@@ -9,11 +9,13 @@ define(
     var hash = __dependency5__.hash;
     var defer = __dependency6__.defer;
     var config = __dependency7__.config;
+    var resolve = __dependency8__.resolve;
 
     function configure(name, value) {
       config[name] = value;
     }
 
+
     __exports__.Promise = Promise;
     __exports__.EventTarget = EventTarget;
     __exports__.all = all;
@@ -21,4 +23,5 @@ define(
     __exports__.defer = defer;
     __exports__.denodeify = denodeify;
     __exports__.configure = configure;
+    __exports__.resolve = resolve;
   });

browser/rsvp.js

@@ -499,12 +499,54 @@ define("rsvp/promise",
       });
     }
 
+
     __exports__.Promise = Promise;
   });
 
+define("rsvp/resolve",
+  ["rsvp/promise","exports"],
+  function(__dependency1__, __exports__) {
+    "use strict";
+    var Promise = __dependency1__.Promise;
+
+
+    function objectOrFunction(x) {
+      return typeof x === "function" || (typeof x === "object" && x !== null);
+    }
+
+    function resolve(thenable){
+      var promise = new Promise(function(resolve, reject){
+        var then;
+
+        try {
+          if ( objectOrFunction(thenable) ) {
+            then = thenable.then;
+
+            if (typeof then === "function") {
+              then.call(thenable, resolve, reject);
+            } else {
+              resolve(thenable);
+            }
+
+          } else {
+            resolve(thenable);
+          }
+
+        } catch(error) {
+          reject(error);
+        }
+      });
+
+      return promise;
+    }
+
+
+    __exports__.resolve = resolve;
+  });
+
 define("rsvp",
-  ["rsvp/events","rsvp/promise","rsvp/node","rsvp/all","rsvp/hash","rsvp/defer","rsvp/config","exports"],
-  function(__dependency1__, __dependency2__, __dependency3__, __dependency4__, __dependency5__, __dependency6__, __dependency7__, __exports__) {
+  ["rsvp/events","rsvp/promise","rsvp/node","rsvp/all","rsvp/hash","rsvp/defer","rsvp/config","rsvp/resolve","exports"],
+  function(__dependency1__, __dependency2__, __dependency3__, __dependency4__, __dependency5__, __dependency6__, __dependency7__, __dependency8__, __exports__) {
     "use strict";
     var EventTarget = __dependency1__.EventTarget;
     var Promise = __dependency2__.Promise;
@@ -513,11 +555,13 @@ define("rsvp",
     var hash = __dependency5__.hash;
     var defer = __dependency6__.defer;
     var config = __dependency7__.config;
+    var resolve = __dependency8__.resolve;
 
     function configure(name, value) {
       config[name] = value;
     }
 
+
     __exports__.Promise = Promise;
     __exports__.EventTarget = EventTarget;
     __exports__.all = all;
@@ -525,6 +569,7 @@ define("rsvp",
     __exports__.defer = defer;
     __exports__.denodeify = denodeify;
     __exports__.configure = configure;
+    __exports__.resolve = resolve;
   });
 
 window.RSVP = requireModule('rsvp');

browser/rsvp/promise.amd.js

@@ -135,5 +135,6 @@ define(
       });
     }
 
+
     __exports__.Promise = Promise;
   });

browser/rsvp/resolve.amd.js

+define(
+  ["rsvp/promise","exports"],
+  function(__dependency1__, __exports__) {
+    "use strict";
+    var Promise = __dependency1__.Promise;
+
+
+    function objectOrFunction(x) {
+      return typeof x === "function" || (typeof x === "object" && x !== null);
+    }
+
+    function resolve(thenable){
+      var promise = new Promise(function(resolve, reject){
+        var then;
+
+        try {
+          if ( objectOrFunction(thenable) ) {
+            then = thenable.then;
+
+            if (typeof then === "function") {
+              then.call(thenable, resolve, reject);
+            } else {
+              resolve(thenable);
+            }
+
+          } else {
+            resolve(thenable);
+          }
+
+        } catch(error) {
+          reject(error);
+        }
+      });
+
+      return promise;
+    }
+
+
+    __exports__.resolve = resolve;
+  });

lib/rsvp.js

@@ -5,9 +5,10 @@ import { all } from "rsvp/all";
 import { hash } from "rsvp/hash";
 import { defer } from "rsvp/defer";
 import { config } from "rsvp/config";
+import { resolve } from "rsvp/resolve";
 
 function configure(name, value) {
   config[name] = value;
 }
 
-export { Promise, EventTarget, all, hash, defer, denodeify, configure };
\ No newline at end of file
+export { Promise, EventTarget, all, hash, defer, denodeify, configure, resolve };

lib/rsvp/resolve.js

+import { Promise } from "rsvp/promise";
+
+
+function objectOrFunction(x) {
+  return typeof x === "function" || (typeof x === "object" && x !== null);
+}
+
+function resolve(thenable){
+  var promise = new Promise(function(resolve, reject){
+    var then;
+
+    try {
+      if ( objectOrFunction(thenable) ) {
+        then = thenable.then;
+
+        if (typeof then === "function") {
+          then.call(thenable, resolve, reject);
+        } else {
+          resolve(thenable);
+        }
+
+      } else {
+        resolve(thenable);
+      }
+
+    } catch(error) {
+      reject(error);
+    }
+  });
+
+  return promise;
+}
+
+export { resolve };

tests/extension-tests.js

@@ -520,4 +520,277 @@ describe("RSVP extensions", function() {
       });
     });
   });
+
+  describe("RSVP.resolve", function(){
+    specify("it should exist", function(){
+      assert(RSVP.resolve);
+    });
+
+    describe("1. If x is a promise, adopt its state ", function(){
+      specify("1.1 If x is pending, promise must remain pending until x is fulfilled or rejected.", function(done){
+        var expectedValue, resolver, thenable, wrapped;
+
+        expectedValue = 'the value';
+        thenable = {
+          then: function(resolve, reject){
+            resolver = resolve;
+          }
+        };
+
+        wrapped = RSVP.resolve(thenable);
+
+        wrapped.then(function(value){
+          assert(value === expectedValue);
+          done();
+        })
+        resolver(expectedValue);
+
+      });
+
+      specify("1.2 If/when x is fulfilled, fulfill promise with the same value.", function(done){
+        var expectedValue, thenable, wrapped;
+
+        expectedValue = 'the value';
+        thenable = {
+          then: function(resolve, reject){
+            resolve(expectedValue);
+          }
+        };
+
+        wrapped = RSVP.resolve(thenable);
+
+        wrapped.then(function(value){
+          assert(value === expectedValue);
+          done();
+        })
+      });
+
+      specify("1.3 If/when x is rejected, reject promise with the same reason.", function(done){
+        var expectedError, thenable, wrapped;
+
+        expectedError =  new Error();
+        thenable = {
+          then: function(resolve, reject){
+            reject(expectedError);
+          }
+        };
+
+        wrapped = RSVP.resolve(thenable);
+
+        wrapped.then(null, function(error){
+          assert(error === expectedError);
+          done();
+        });
+      });
+    });
+
+    describe("2. Otherwise, if x is an object or function,", function(){
+      specify("2.1 Let then x.then", function(done){
+        var accessCount, resolver, wrapped, thenable;
+
+        accessCount = 0;
+        thenable = { };
+
+        Object.defineProperty(thenable, 'then', {
+          get: function(){
+            accessCount++;
+
+            if (accessCount > 1) {
+              throw new Error();
+            }
+
+            return function(){ };
+          }
+        });
+
+        assert(accessCount === 0);
+
+        wrapped = RSVP.resolve(thenable);
+
+        assert(accessCount === 1);
+
+        done();
+      });
+
+      specify("2.2 If retrieving the property x.then results in a thrown exception e, reject promise with e as the reason.", function(done){
+        var wrapped, thenable, expectedError;
+
+        expectedError = new Error();
+        thenable = { };
+
+        Object.defineProperty(thenable, 'then', {
+          get: function(){
+            throw expectedError;
+          }
+        });
+
+        wrapped = RSVP.resolve(thenable);
+
+        wrapped.then(null, function(error){
+          assert(error === expectedError, 'incorrect exception was thrown');
+          done();
+        });
+      });
+
+      describe('2.3. If then is a function, call it with x as this, first argument resolvePromise, and second argument rejectPromise, where', function(){
+        specify('2.3.1 If/when resolvePromise is called with a value y, run Resolve(promise, y)', function(done){
+          var expectedSuccess, resolver, rejector, thenable, wrapped, calledThis;
+
+          thenable = {
+            then: function(resolve, reject){
+              calledThis = this;
+              resolver = resolve;
+              rejector = reject;
+            }
+          };
+
+          expectedSuccess = 'success';
+          wrapped = RSVP.resolve(thenable);
+
+          wrapped.then(function(success){
+            assert(calledThis === thenable, 'this must be the thenable');
+            assert(success === expectedSuccess, 'rejected promise with x');
+            done();
+          });
+
+          resolver(expectedSuccess);
+        });
+
+        specify('2.3.2 If/when rejectPromise is called with a reason r, reject promise with r.', function(done){
+          var expectedError, resolver, rejector, thenable, wrapped, calledThis,
+
+          thenable = {
+            then: function(resolve, reject){
+              calledThis = this;
+              resolver = resolve;
+              rejector = reject;
+            }
+          };
+
+          expectedError = new Error();
+
+          wrapped = RSVP.resolve(thenable);
+
+          wrapped.then(null, function(error){
+            assert(error === expectedError, 'rejected promise with x');
+            done();
+          });
+
+          rejector(expectedError);
+        });
+
+        specify("2.3.3 If both resolvePromise and rejectPromise are called, or multiple calls to the same argument are made, the first call takes precedence, and any further calls are ignored", function(done){
+          var expectedError, expectedSuccess, resolver, rejector, thenable, wrapped, calledThis,
+          calledRejected, calledResolved;
+
+          calledRejected = 0;
+          calledResolved = 0;
+
+          thenable = {
+            then: function(resolve, reject){
+              calledThis = this;
+              resolver = resolve;
+              rejector = reject;
+            }
+          };
+
+          expectedError = new Error();
+
+          wrapped = RSVP.resolve(thenable);
+
+          wrapped.then(function(){
+            calledResolved++;
+          }, function(error){
+            calledRejected++;
+            assert(calledResolved === 0, 'never resolved');
+            assert(calledRejected === 1, 'rejected only once');
+            assert(error === expectedError, 'rejected promise with x');
+            done();
+          });
+
+          rejector(expectedError);
+          rejector(expectedError);
+          resolver();
+        });
+
+        describe("2.3.4 If calling then throws an exception e", function(){
+          specify("2.3.4.1 If resolvePromise or rejectPromise have been called, ignore it.", function(done){
+            var expectedSuccess, resolver, rejector, thenable, wrapped, calledThis,
+            calledRejected, calledResolved;
+
+            expectedSuccess = 'success';
+
+            thenable = {
+              then: function(resolve, reject){
+                resolve(expectedSuccess);
+                throw expectedError;
+              }
+            };
+
+            wrapped = RSVP.resolve(thenable);
+
+            wrapped.then(function(success){
+              assert(success === expectedSuccess, 'resolved not errored');
+              done();
+            });
+          });
+
+          specify("2.3.4.2 Otherwise, reject promise with e as the reason.", function(done) {
+            var expectedError, resolver, rejector, thenable, wrapped, calledThis, callCount;
+
+            expectedError = new Error();
+            callCount = 0;
+
+            thenable = { then: function() { throw expectedError; } };
+
+            wrapped = RSVP.resolve(thenable);
+
+            wrapped.then(null, function(error){
+              callCount++;
+              assert(expectedError === error, 'expected the correct error to be rejected');
+              done();
+            });
+
+            assert(callCount === 0, 'expected async, was sync');
+          });
+        });
+      });
+
+      specify("2.4 If then is not a function, fulfill promise with x", function(done){
+        var expectedError, resolver, rejector, thenable, wrapped, calledThis, callCount;
+
+        thenable = { then: 3 };
+        callCount = 0;
+        wrapped = RSVP.resolve(thenable);
+
+        wrapped.then(function(success){
+          callCount++;
+          assert(thenable === success, 'fulfilled promise with x');
+          done();
+        });
+
+        assert(callCount === 0, 'expected async, was sync');
+      });
+    });
+
+    describe("3. If x is not an object or function, ", function(){
+      specify("fulfill promise with x.", function(done){
+        var thenable, callCount, wrapped;
+
+        thenable = null;
+        callCount = 0;
+        wrapped = RSVP.resolve(thenable);
+
+        wrapped.then(function(success){
+          callCount++;
+          assert(success === thenable, 'fulfilled promise with x');
+          done();
+        }, function(a){
+          assert(false, 'should not also reject');
+        });
+
+        assert(callCount === 0, 'expected async, was sync');
+      });
+    });
+  });
 });