Added a basic set of async matchers

- Fixes #1447
- Fixes #1547

src/core/AsyncExpectation.js

@@ -0,0 +1,153 @@
+getJasmineRequireObj().AsyncExpectation = function(j$) {
+  var promiseForMessage = {
+    jasmineToString: function() { return 'a promise'; }
+  };
+
+  /**
+   * Asynchronous matchers.
+   * @namespace async-matchers
+   */
+  function AsyncExpectation(options) {
+    var global = options.global || j$.getGlobal();
+    this.util = options.util || { buildFailureMessage: function() {} };
+    this.customEqualityTesters = options.customEqualityTesters || [];
+    this.addExpectationResult = options.addExpectationResult || function(){};
+    this.actual = options.actual;
+    this.isNot = options.isNot;
+
+    if (!global.Promise) {
+      throw new Error('expectAsync is unavailable because the environment does not support promises.');
+    }
+
+    if (!j$.isPromise(this.actual)) {
+      throw new Error('Expected expectAsync to be called with a promise.');
+    }
+
+    ['toBeResolved', 'toBeRejected', 'toBeResolvedTo'].forEach(wrapCompare.bind(this));
+  }
+
+  function wrapCompare(name) {
+    var compare = this[name];
+    this[name] = function() {
+      var self = this;
+      var args = Array.prototype.slice.call(arguments);
+      args.unshift(this.actual);
+
+      // Capture the call stack here, before we go async, so that it will
+      // contain frames that are relevant to the user instead of just parts
+      // of Jasmine.
+      var errorForStack = j$.util.errorWithStack();
+
+      return compare.apply(self, args).then(function(result) {
+        var message;
+
+        if (self.isNot) {
+          result.pass = !result.pass;
+        }
+
+        args[0] = promiseForMessage;
+        message = j$.Expectation.finalizeMessage(self.util, name, self.isNot, args, result);
+
+        self.addExpectationResult(result.pass, {
+          matcherName: name,
+          passed: result.pass,
+          message: message,
+          error: undefined,
+          errorForStack: errorForStack,
+          actual: self.actual
+        });
+      });
+    };
+  }
+
+  /**
+   * Expect a promise to be resolved.
+   * @function
+   * @async
+   * @name async-matchers#toBeResolved
+   * @example
+   * await expectAsync(aPromise).toBeResolved();
+   * @example
+   * return expectAsync(aPromise).toBeResolved();
+   */
+  AsyncExpectation.prototype.toBeResolved = function(actual) {
+    return actual.then(
+      function() { return {pass: true}; },
+      function() { return {pass: false}; }
+    );
+  };
+
+  /**
+   * Expect a promise to be rejected.
+   * @function
+   * @async
+   * @name async-matchers#toBeRejected
+   * @example
+   * await expectAsync(aPromise).toBeRejected();
+   * @example
+   * return expectAsync(aPromise).toBeRejected();
+   */
+  AsyncExpectation.prototype.toBeRejected = function(actual) {
+    return actual.then(
+      function() { return {pass: false}; },
+      function() { return {pass: true}; }
+    );
+  };
+
+  /**
+   * Expect a promise to be resolved to a value equal to the expected, using deep equality comparison.
+   * @function
+   * @async
+   * @name async-matchers#toBeResolvedTo
+   * @param {Object} expected - Value that the promise is expected to resolve to
+   * @example
+   * await expectAsync(aPromise).toBeResolvedTo({prop: 'value'});
+   * @example
+   * return expectAsync(aPromise).toBeResolvedTo({prop: 'value'});
+   */
+  AsyncExpectation.prototype.toBeResolvedTo = function(actualPromise, expectedValue) {
+    var self = this;
+
+    function prefix(passed) {
+      return 'Expected a promise ' +
+        (passed ? 'not ' : '') +
+        'to be resolved to ' + j$.pp(expectedValue);
+    }
+
+    return actualPromise.then(
+      function(actualValue) {
+        if (self.util.equals(actualValue, expectedValue, self.customEqualityTesters)) {
+          return {
+           pass: true,
+           message: prefix(true) + '.'
+         };
+        } else {
+          return {
+            pass: false,
+            message: prefix(false) + ' but it was resolved to ' + j$.pp(actualValue) + '.'
+          };
+        }
+      },
+      function() {
+        return {
+          pass: false,
+          message: prefix(false) + ' but it was rejected.'
+        };
+      }
+    );
+  };
+
+
+  AsyncExpectation.factory = function(options) {
+    var expect = new AsyncExpectation(options);
+
+    options = j$.util.clone(options);
+    options.isNot = true;
+    expect.not = new AsyncExpectation(options);
+
+    return expect;
+  };
+
+
+  return AsyncExpectation;
+};