다운로드 Salesforce : JS-Dev-101 질문 & 답 PDF & Test Software

Refer to the code below (assuming Promise.race is intended):
let cat3 = new Promise(resolve =>
setTimeout(resolve, 3000, "Cat 3 completes")
);
Promise.race([cat1, cat2, cat3])
.then(value => {
let result = `${value} the race.`;
})
.catch(err => {
console.log("Race is cancelled:", err);
});
(Assuming cat1 and cat2 are similar to earlier examples: cat2 resolves fastest.) What is the value of result when Promise.race executes?

• A. Car 1 crashed on the race.
• B. Car 2 completed the race.
• C. Race is cancelled.
• D. Car 3 completed the race.

Console logging methods that allow string substitution:

• A. assert
• B. message
• C. log
• D. info
• E. error

A team at Universal Containers works on a big project and uses Yarn to deal with the project's dependencies. A developer added a dependency to manipulate dates and pushed the updates to the remote repository. The rest of the team complains that the dependency does not get downloaded when they execute yarn.
What could be the reason for this?

• A. The developer missed the option --save when adding the dependency.
• B. The developer missed the option --add when adding the dependency.
• C. The developer added the dependency as a dev dependency, and YARN_ENV is set to production.
• D. The developer added the dependency as a dev dependency, and NODE_ENV is set to production.

Corrected code:
let a = "*";
let b = "**";
// x = 3;
console.log(a);
What is displayed when the code executes?

• A. undefined
• B. *
• C. ReferenceError: a is not defined
• D. null

A class was written to represent items for purchase in an online store, and a second class representing items that are on sale at a discounted price. The constructor sets the name to the first value passed in. There is a new requirement for a developer to implement a description method that will return a brief description for Item and SaleItem.
01 let regItem = new Item('Scarf', 55);
02 let saleItem = new SaleItem('Shirt', 80, .1);
03 Item.prototype.description = function() { return 'This is a ' + this.name; }
04 console.log(regItem.description());
05 console.log(saleItem.description());
06
07 SaleItem.prototype.description = function() { return 'This is a discounted ' + this.name; } What is the output when executing the code above?

• A. This is a Scarf
  This is a Shirt
  This is a Scarf
  This is a discounted Shirt
• B. This is a Scarf
  This is a Shirt
  This is a discounted Scarf
  This is a discounted Shirt
• C. This is a Scarf
  Uncaught TypeError: saleItem.description is not a function
  This is a Shirt
  This is a discounted Shirt
• D. This is a Scarf
  Uncaught TypeError: saleItem.description is not a function
  This is a Scarf
  This is a discounted Shirt