rewire/test/__get__.test.js

Dependency injection for node.js applications

"use strict"; // run code in ES5 strict mode

var expect = require("expect.js"),
    vm = require("vm"),
    __get__ = require("../lib/__get__.js"),

    expectReferenceError = expectError(ReferenceError),
    expectTypeError = expectError(TypeError);

function expectError(ErrConstructor) {
    return function expectReferenceError(err) {
        expect(err.constructor.name).to.be(ErrConstructor.name);
    };
}


describe("__get__", function () {
    var moduleFake;

    beforeEach(function () {
        moduleFake = {
            myNumber: 0,
            myObj: {}
        };

        vm.runInNewContext(
            "__get__ = " + __get__.toString() + "; " +
            "setNumber = function (value) { myNumber = value; }; " +
            "setObj = function (value) { myObj = value; }; ",
            moduleFake
        );
    });
    it("should return the initial value", function () {
        expect(moduleFake.__get__("myNumber")).to.be(0);
        expect(moduleFake.__get__("myObj")).to.eql({});
    });
    it("should return the changed value of the number", function () {
        var newObj = { hello: "hello" };

        moduleFake.setNumber(2);
        moduleFake.setObj(newObj);
        expect(moduleFake.__get__("myNumber")).to.be(2);
        expect(moduleFake.__get__("myObj")).to.be(newObj);
    });
    it("should throw a ReferenceError when getting not existing vars", function () {
        expect(function () {
            moduleFake.__get__("blabla");
        }).to.throwException(expectReferenceError);
    });
    it("should throw a TypeError when passing misfitting params", function () {
        expect(function () {
            moduleFake.__get__();
        }).to.throwException(expectTypeError);
        expect(function () {
            moduleFake.__get__(undefined);
        }).to.throwException(expectTypeError);
        expect(function () {
            moduleFake.__get__(null);
        }).to.throwException(expectTypeError);
        expect(function () {
            moduleFake.__get__(true);
        }).to.throwException(expectTypeError);
        expect(function () {
            moduleFake.__get__(2);
        }).to.throwException(expectTypeError);
        expect(function () {
            moduleFake.__get__("");
        }).to.throwException(expectTypeError);
        expect(function () {
            moduleFake.__get__([]);
        }).to.throwException(expectTypeError);
        expect(function () {
            moduleFake.__get__({});
        }).to.throwException(expectTypeError);
        expect(function () {
            moduleFake.__get__(function () {});
        }).to.throwException(expectTypeError);
    });
});