Salesforce Certified JavaScript Developer I (CRT-600) Free Practice Test
Question 1
Given the following code:
let x = null;
console.log(typeof x);
What is the output?
let x = null;
console.log(typeof x);
What is the output?
Correct Answer: C
Question 2
A developer is required to write a function that calculates the sum of elements in an array but is getting undefined every time the code is executed. The developer needs to find what is missing in the code below.
Const sumFunction = arr => {
Return arr.reduce((result, current) => {
//
Result += current;
//
), 10);
);
Which option makes the code work as expected?
Const sumFunction = arr => {
Return arr.reduce((result, current) => {
//
Result += current;
//
), 10);
);
Which option makes the code work as expected?
Correct Answer: B
Question 3
A test has a dependency on database.query. During the test the dependency is replaced with an object called database with the method, query, that returns an array. The developer needs to verify how many times the method was called and the arguments used each time.
Which two test approaches describe the requirement?
Choose 2 answers
Which two test approaches describe the requirement?
Choose 2 answers
Correct Answer: A,C
Question 4
Refer to code below:
function Person() {
this.firstName = 'John';
}
Person.prototype ={
Job: x => 'Developer'
};
const myFather = new Person();
const result =myFather.firstName + ' ' + myFather.job();
What is the value of the result after line 10 executes?
function Person() {
this.firstName = 'John';
}
Person.prototype ={
Job: x => 'Developer'
};
const myFather = new Person();
const result =myFather.firstName + ' ' + myFather.job();
What is the value of the result after line 10 executes?
Correct Answer: D
Question 5
Which three browser specific APIs are available for developers to persist data between page loads ?
Choose 3 answers
Choose 3 answers
Correct Answer: C,D,E
Question 6
Refer to the code below:
Const resolveAfterMilliseconds = (ms) => Promise.resolve (
setTimeout (( => console.log(ms), ms ));
Const aPromise = await resolveAfterMilliseconds(500);
Const bPromise = await resolveAfterMilliseconds(500);
Await aPromise, wait bPromise;
What is the result of running line 05?
Const resolveAfterMilliseconds = (ms) => Promise.resolve (
setTimeout (( => console.log(ms), ms ));
Const aPromise = await resolveAfterMilliseconds(500);
Const bPromise = await resolveAfterMilliseconds(500);
Await aPromise, wait bPromise;
What is the result of running line 05?
Correct Answer: A
Question 7
Refer to the code:
Given the code above, which three properties are set for pet1? Choose 3 answers
Given the code above, which three properties are set for pet1? Choose 3 answers
Correct Answer: A,B,D
Question 8
Cloud Kicks has a class to represent items for sale in an online store, as shown below:
Class Item{
constructor (name, price){
this.name = name;
this.price = price;
}
formattedPrice(){
return 's' + String(this.price);}}
A new business requirement comes in that requests a ClothingItem class that should have all of the properties and methods of the Item class but will also have properties that are specific to clothes.
Which line of code properly declares the clothingItem class such that it inherits from Item?
Class Item{
constructor (name, price){
this.name = name;
this.price = price;
}
formattedPrice(){
return 's' + String(this.price);}}
A new business requirement comes in that requests a ClothingItem class that should have all of the properties and methods of the Item class but will also have properties that are specific to clothes.
Which line of code properly declares the clothingItem class such that it inherits from Item?
Correct Answer: A
Question 9
Refer to the code below:
console.log(''start);
Promise.resolve('Success') .then(function(value){
console.log('Success');
});
console.log('End');
What is the output after the code executes successfully?
console.log(''start);
Promise.resolve('Success') .then(function(value){
console.log('Success');
});
console.log('End');
What is the output after the code executes successfully?
Correct Answer: B
Question 10
A developer is setting up a Node,js server and is creating a script at the root of the source code, index,js, that will start the server when executed. The developer declares a variable that needs the folder location that the code executes from.
Which global variable can be used in the script?
Which global variable can be used in the script?
Correct Answer: C
Question 11
Refer to code below:
Let first = 'who';
Let second = 'what';
Try{
Try{
Throw new error('Sad trombone');
}catch (err){
First ='Why';
}finally {
Second ='when';
} catch (err) {
Second ='Where';
}
What are the values for first and second once the code executes ?
Let first = 'who';
Let second = 'what';
Try{
Try{
Throw new error('Sad trombone');
}catch (err){
First ='Why';
}finally {
Second ='when';
} catch (err) {
Second ='Where';
}
What are the values for first and second once the code executes ?
Correct Answer: A