meteor/packages/ecmascript/runtime-tests.js

const isNode8OrLater = Meteor.isServer && parseInt(process.versions.node) >= 8;

Tinytest.add('ecmascript - runtime - template literals', test => {
  function dump(strings, ...expressions) {
    const copy = Object.create(null);
    Object.assign(copy, strings);
    copy.raw = strings.raw;
    return [copy, expressions];
  }

  const foo = 'B';

  test.equal(`\u0041${foo}C`, 'ABC');

  test.equal(dump`\u0041${foo}C`, [
    {
      0: 'A',
      1: 'C',
      raw: ['\\u0041', 'C'],
    },
    ['B'],
  ]);
});

Tinytest.add('ecmascript - runtime - classes - basic', test => {
  {
    class Foo {
      constructor(x) {
        this.x = x;
      }
    }

    // Babel 7 no longer forbids constructor calls in loose mode.
    // test.throws(() => {
    //   Foo(); // called without `new`
    // });

    test.equal(new Foo(3).x, 3);
  }

  {
    class Bar {
      constructor(x) {
        this.x = x;
      }
    }
    class Foo extends Bar {}

    // Babel 7 no longer forbids constructor calls in loose mode.
    // test.throws(() => {
    //   Foo(); // called without `new`
    // });

    test.equal(new Foo(3).x, 3);
    test.isTrue(new Foo(3) instanceof Foo);
    test.isTrue(new Foo(3) instanceof Bar);
  }

  {
    class Foo {
      static staticMethod() {
        return 'classy';
      }

      prototypeMethod() {
        return 'prototypical';
      }
    }

    test.equal(Foo.staticMethod(), 'classy');
    test.equal(new Foo().prototypeMethod(), 'prototypical');
  }
});

Tinytest.add('ecmascript - runtime - classes - use before declare', test => {
  const x = function asdf() {};
  if (typeof asdf === 'function') {
    // We seem to be in IE 8, where function names leak into the enclosing
    // scope, contrary to the spec.  In this case, Babel does not (currently)
    // throw an error if you use a class before you declare it.  (Of course,
    // any other browser can tell the developer they screwed up!)
    test.expect_fail();
  }

  test.throws(() => {
    new Foo(); // use before definition
    class Foo {}
  });
});

Tinytest.add('ecmascript - runtime - classes - inheritance', test => {
  // uses `babelHelpers.inherits`
  {
    class Foo {
      static static1() {
        return 1;
      }
    }
    Foo.static2 = function() {
      return 2;
    };

    // static methods are inherited!
    class Bar extends Foo {}

    test.equal(Foo.static1(), 1);
    test.equal(Foo.static2(), 2);
    test.equal(Bar.static1(), 1);
    test.equal(Bar.static2(), 2);
  }

  {
    const buf = [];
    class Foo {
      constructor() {
        buf.push('hi');
      }
    }

    class Bar extends Foo {}

    new Bar();
    // derived class with no constructor gets a default constructor
    // that calls the super constructor
    test.equal(buf, ['hi']);
  }
});

Tinytest.add('ecmascript - runtime - classes - computed props', test => {
  {
    const frob = 'inc';

    class Foo {
      static [frob](n) {
        return n + 1;
      }
    }

    test.equal(Foo.inc(3), 4);
  }
});

if (Meteor.isServer) {
  // getters and setters don't work in all clients, but they should work
  // in classes on browsers that support them in the first place, and on
  // the server.  (Technically they just need a working
  // Object.defineProperty, found in IE9+ and all modern environments.)
  Tinytest.add('ecmascript - runtime - classes - getters/setters', test => {
    // uses `babelHelpers.createClass`
    class Foo {
      get two() {
        return 1 + 1;
      }
      static get three() {
        return 1 + 1 + 1;
      }
    }

    test.equal(new Foo().two, 2);
    test.equal(Foo.three, 3);
  });
}

export const testExport = 'oyez';

Tinytest.add('ecmascript - runtime - classes - properties', test => {
  class ClassWithProperties {
    property = ['prop', 'rty'].join('e');
    static staticProp = 1234;

    check = self => {
      import { testExport as oyez } from './runtime-tests.js';
      test.equal(oyez, 'oyez');
      test.isTrue(self === this);
      test.equal(this.property, 'property');
    };

    method() {
      import { testExport as oyez } from './runtime-tests.js';
      test.equal(oyez, 'oyez');
    }
  }

  test.equal(ClassWithProperties.staticProp, 1234);

  const cwp = new ClassWithProperties();

  cwp.check(cwp);

  // Check binding of arrow function.
  cwp.check.call(null, cwp);

  cwp.method();
});

Tinytest.add('ecmascript - runtime - block scope', test => {
  {
    const buf = [];
    const thunks = [];
    function print(x) {
      buf.push(x);
    }
    function doLater(f) {
      thunks.push(f);
    }

    for (let i = 0; i < 3; i++) {
      print(i);
    }
    test.equal(buf, [0, 1, 2]);
    buf.length = 0;

    for (let i = 0; i < 3; i++) {
      doLater(() => {
        print(i);
      });
    }

    thunks.forEach(f => f());
    test.equal(buf, [0, 1, 2]);
  }
});

Tinytest.add('ecmascript - runtime - classes - super', test => {
  {
    class Class1 {
      foo() {
        return 123;
      }
      static bar() {
        return 1;
      }
    }
    class Class2 extends Class1 {}
    class Class3 extends Class2 {
      foo() {
        return super.foo() + Class3.bar();
      }
    }

    test.equal(new Class3().foo(), 124);
  }

  {
    class Foo {
      constructor(value) {
        this.value = value;
      }
      x() {
        return this.value;
      }
    }

    class Bar extends Foo {
      constructor() {
        super(123);
      }
      x() {
        return super.x();
      }
    }

    test.equal(new Bar().x(), 123);
  }
});

Tinytest.add('ecmascript - runtime - object rest/spread', test => {
  const middle = { b: 2, c: 3 };
  // uses `babelHelpers._extends`
  const full = { a: 1, ...middle, d: 4 };
  test.equal(full, { a: 1, b: 2, c: 3, d: 4 });
});

Tinytest.add('ecmascript - runtime - spread args to new', test => {
  const Foo = function(one, two, three) {
    test.isTrue(this instanceof Foo);
    test.equal(one, 1);
    test.equal(two, 2);
    test.equal(three, 3);
    this.created = true;
  };

  const oneTwo = [1, 2];

  // uses `babelHelpers.bind`
  const foo = new Foo(...oneTwo, 3);
  test.isTrue(foo.created);
});

Tinytest.add('ecmascript - runtime - Map spread', test => {
  const map = new Map();

  map.set(0, 1);
  map.set(1, 2);
  map.set(2, 3);

  test.equal(
    [...map],
    [
      [0, 1],
      [1, 2],
      [2, 3],
    ]
  );
});

Tinytest.add('ecmascript - runtime - Set spread', test => {
  const set = new Set();

  set.add('a');
  set.add(1);
  set.add(false);

  test.equal([...set], ['a', 1, false]);
});

Tinytest.add('ecmascript - runtime - destructuring', test => {
  const obj = { a: 1, b: 2 };
  const { a, ...rest } = obj;
  test.equal(a, 1);
  test.equal(rest, { b: 2 });

  const {} = {};

  test.throws(() => {
    const {} = null;
  });

  const [x, y, z] = (function*() {
    let n = 1;
    while (true) {
      yield n++;
    }
  })();

  test.equal(x, 1);
  test.equal(y, 2);
  test.equal(z, 3);
});