path: root/scorpion-tests.js

/*global describe,it,expect,beforeEach,Scorpion, setTimeout*/

describe("deferred", function() {
    var deferred, promise;
    beforeEach(function() {
        deferred = Scorpion.defer();
        promise = deferred.promise;
    });
    this.timeout(100);

    describe("promise", function() {
        it("should have a 'then' method", function() {
            expect(promise.then).not.to.equal(undefined);
        });

        it("should be able to chain 'then' methods", function() {
            var promise1 = promise;
            var promise2 = promise1.then(function(x) {
                return x + 1;
            });
            var promise3 = promise1.then(function(x) {
                return x + 1;
            });
            expect(promise1.then).not.to.equal(undefined);
            expect(promise2.then).not.to.equal(undefined);
            expect(promise3.then).not.to.equal(undefined);
        });
    });

    describe("resolution", function() {

        it("should resolve asynchronously", function(done) {
            var hasRun = false;
            promise.then(function(val) {
                hasRun = true;
                return val;
            });
            deferred.resolve("value");
            expect(hasRun).to.equal(false);
            setTimeout(function() {
                expect(hasRun).to.equal(true);
                done();
            });
        });

        it("should propagate through multiple promises", function(done) {
            var promise2 = promise.then(function(value) {
                return value + 1;
            });
            var promise3 = promise2.then(function(value) {
                return value + 1;
            });
            promise3.then(function(value) {
                expect(value).to.equal(3);
                done();
            });
            deferred.resolve(1);
        });

        it("should call all registered handlers", function(done) {
            var called = 0;
            promise.then(function() {called++;});
            promise.then(function() {called++;});
            promise.then(function() {called++;});
            expect(called).to.equal(0);
            deferred.resolve(null);
            setTimeout(function() {
                expect(called).to.equal(3);
                done();
            });
        });

        it("should call handlers, even when added after resolution", function(done) {
            deferred.resolve(null);
            promise.then(function() {
                done();
            });
        });

        it("should not allow multiple resolution", function() {
            deferred.resolve(1);
            expect(function() {
                deferred.resolve(2);
            }).to.throw();
        });

        it("should not allow rejecting after resolving", function() {
            deferred.resolve(1);
            expect(function() {
                deferred.reject(2);
            }).to.throw();
        });

        it("should handle a returned promise by 'unwrapping' it", function(done) {
            promise.then(function(value) {
                var deferred = Scorpion.defer();
                deferred.resolve(value + 1);
                return deferred.promise;
            }).then(function(value) {
                try {
                    expect(value).to.equal(2);
                    done();
                } catch (e) {
                    done(e);
                }
            });
            deferred.resolve(1);
        });
    });

    describe("rejection", function() {
        it("should reject asynchronously", function(done) {
            var hasRun = false;
            promise.then(null, function(val) {
                hasRun = true;
                return val;
            });
            deferred.reject("value");
            expect(hasRun).to.equal(false);
            setTimeout(function() {
                expect(hasRun).to.equal(true);
                done();
            });
        });


        it("should be turned into resolution by a handler", function(done) {
            var promise2 = promise.then(function(value) {
                return value + 1;
            }, function(value) {
                return value + 100;
            });
            promise2.then(function(value) {
                try {
                    expect(value).to.equal(101);
                    done();
                } catch (e)  {
                    done(e);
                }
            });
            deferred.reject(1);
        });

        it("should call all registered handlers", function(done) {
            var called = 0;
            promise.then(null, function() {called++;});
            promise.then(null, function() {called++;});
            promise.then(null, function() {called++;});
            expect(called).to.equal(0);
            deferred.reject(null);
            setTimeout(function() {
                expect(called).to.equal(3);
                done();
            });
        });

        it("should not allow multiple rejection", function() {
            deferred.reject(1);
            expect(function() {
                deferred.reject(2);
            }).to.throw();
        });

        it("should not allow resolving after rejecting", function() {
            deferred.reject(1);
            expect(function() {
                deferred.resolve(2);
            }).to.throw();
        });

        it("should call handlers, even when added after resolution", function(done) {
            deferred.reject(null);
            promise.then(null, function() {
                done();
            });
        });

        it("should handle a returned promise by 'unwrapping' in the error case", function(done) {
            promise.then(function(value) {
                var deferred = Scorpion.defer();
                deferred.reject(value + 1);
                return deferred.promise;
            }).then(null, function(value) {
                try {
                    expect(value).to.equal(2);
                    done();
                } catch (e) {
                    done(e);
                }
            });
            deferred.resolve(1);
        });
    });

    describe("waitForAll", function() {
        it("should resolve with an array if all successful", function(done) {
            var d1 = Scorpion.defer(),
                d2 = Scorpion.defer(),
                d3 = Scorpion.defer();
            Scorpion
                .waitForAll([d1.promise, d2.promise, d3.promise])
                .then(function(values) {
                    if (values.length == 3 &&
                        values[0] === 0 &&
                        values[1] === 1 &&
                        values[2] === 2) {
                        done();
                    } else {
                        done(new Error("Error in resolved result: " + values));
                    }
                }, done);
            d1.resolve(0);
            d2.resolve(1);
            d3.resolve(2);
        });

        it("should reject with an object of successes/errors if any fail", function(done) {
            var d1 = Scorpion.defer(),
                d2 = Scorpion.defer(),
                d3 = Scorpion.defer();
            Scorpion
                .waitForAll([d1.promise, d2.promise, d3.promise])
                .then(function(values) {
                    done(new Error("incorrectly resolved promise"));
                }, function(e) {
                    if (e.errors && e.values &&
                        e.values[0] === 0 &&
                        e.values[1] === 1 &&
                        e.errors[2] === 2) {
                        done();
                    } else {
                        done(new Error("incorrect reject value"));
                    }
                });
            d1.resolve(0);
            d2.resolve(1);
            d3.reject(2);
        });
    });
});

describe("injector", function() {
    var injector, valuePlugin;
    beforeEach(function() {
        valuePlugin = new Scorpion.ValuePlugin();
        injector = new Scorpion([valuePlugin]);
    });
    this.timeout(100);

    describe("value registration and retrieval", function() {
        it("works", function(done) {
            injector.register("a", function(){return "the value of a";});
            injector.get("a").then(function(value){
                if (value == "the value of a")
                    done();
                else
                    done(new Error("incorrect value for a (" + value + ")"));
            }, done);
        });

        it("with dependencies works", function(done) {
            injector
                .register("a", function(){return "the value of a";})
                .register("b", ["a", function(a){return a.replace(/a/g, "b");}]);
            injector.get("b").then(function(value){
                if (value == "the vblue of b")
                    done();
                else
                    done(new Error("incorrect value for b (" + value + ")"));
            }, done);
        });
    });

    describe("destroy handlers", function() {
        it("work with single gets", function(done) {
            injector.register("a", function(){return "a";});
            expect("a" in valuePlugin.values).to.equal(false);
            var result = injector.get("a");
            result.then(function() {
                if ("a" in valuePlugin.values) {
                    result.destroy().then(function() {
                        if ("a" in valuePlugin.values) {
                            done(new Error("Value found for a after destruction"));
                        } else {
                            done();
                        }
                    });
                } else {
                    done(new Error("No value found for a"));
                }
            }, done);
        });

        it("works with multiple gets", function(done) {
            injector.register("a", function(){return "a";});
            expect("a" in valuePlugin.values).to.equal(false);
            var result = [injector.get("a"), injector.get("a"), injector.get("a")];
            result[1].destroy();
            result[2].destroy();
            result[0].then(function() {
                if ("a" in valuePlugin.values) {
                    result[0].destroy().then(function() {
                        if ("a" in valuePlugin.values) {
                            done(new Error("Value found for a after destruction"));
                        } else {
                            done();
                        }
                    });
                } else {
                    done(new Error("No value found for a"));
                }
            }, done);
        });

        it("works through dependencies", function(done) {
            injector
                .register("a", function(){return "a";})
                .register("b", ["a", function(a){return a + "b";}]);
            expect("a" in valuePlugin.values).to.equal(false);
            var result = injector.get("b");
            result.then(function() {
                if ("a" in valuePlugin.values) {
                    result.destroy().then(function() {
                        if ("a" in valuePlugin.values) {
                            done(new Error("Value found for a after destruction"));
                        } else {
                            done();
                        }
                    });
                } else {
                    done(new Error("No value found for a"));
                }
            }, done);
        });
    });

    describe("cyclic dependency detection", function() {
        it("detects simple cycles", function(done) {
            injector.register("a", ["b", function(b) {return b;}]);
            injector.register("b", ["a", function(a) {return a;}]);
            injector.get("a").then(function() {
                done(new Error("Promise should have been rejected"));
            }, function(e) {
                done();
            });
        });

        it("detects cycles with intermediate nodes", function(done) {
            injector.register("a", ["c", function(c) {return c;}]);
            injector.register("b", ["a", function(a) {return a;}]);
            injector.register("c", ["b", function(b) {return b;}]);
            injector.get("a").then(function() {
                done(new Error("Promise should have been rejected"));
            }, function(e) {
                done();
            });
        });
    });
});