// 6: arrow functions - binding
// To do: make all tests pass, leave the asserts unchanged!
class LexicallyBound {
getFunction() {
return () => {
return this;
}
}
getArgumentsFunction() {
return () => {
return arguments
}
}
}
describe('arrow functions have lexical `this`, no dynamic `this`', () => {
it('bound at definition time, use `=>` ', function() {
var bound = new LexicallyBound();
var fn = bound.getFunction();
assert.strictEqual(fn(), bound);
});
it('can NOT bind a different context', function() {
var bound = new LexicallyBound();
var fn = bound.getFunction();
var anotherObj = bound;
var expected = anotherObj;
assert.strictEqual(fn.call(anotherObj), expected);
});
it('`arguments` doesnt work inside arrow functions', function() {
var bound = new LexicallyBound();
var fn = bound.getArgumentsFunction();
assert.equal(fn(1, 2).length, 0);
});
});
