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NEW QUESTION # 56
Refer to the following object:
const cat ={
firstName: 'Fancy',
lastName: ' Whiskers',
Get fullName() {
return this.firstName + ' ' + this.lastName;
}
};
How can a developer access the fullName property for cat?
- A. cat.get.fullName
- B. cat.fullName()
- C. cat.fullName
- D. cat.function.fullName()
Answer: C
NEW QUESTION # 57
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?
- A. Neither aPromise or bPromise runs.
- B. aPromise and bPromise run sequentially.
- C. aPromise and bPromise run in parallel.
- D. Only aPromise runs.
Answer: A
NEW QUESTION # 58
Refer to the code below:
const searchText = 'Yay! Salesforce is amazing!';
let result1 = searchText.search(/sales/i);
let result2 = searchText.search(/sales/);
console.log(result1);
console.log(result2);
After running this code, which result is displayed on the console?
- A. 5
undefined - B. true
false - C. 5
-1 - D. 5
0
Answer: C
Explanation:
Comprehensive and Detailed Explanation From Exact Extract JavaScript Knowledge:
String: "Yay! Salesforce is amazing!"
Index positions:
'Y' at 0, 'a' at 1, 'y' at 2, '!' at 3, space at 4, 'S' at 5, 'a' at 6, 'l' at 7, 'e' at 8, 's' at 9, etc.
Substring "Sales" starts at index 5.
String.prototype.search with a regex returns the index of the first match or -1 if there is no match.
searchText.search(/sales/i);
/sales/i is case-insensitive because of the i flag.
It matches "Sales" beginning at index 5.
So result1 is 5.
searchText.search(/sales/);
/sales/ is case-sensitive.
It requires lowercase "sales".
The text has "Sales" with uppercase S, so this does not match.
search returns -1 when there is no match.
So result2 is -1.
Console output:
First log: 5
Second log: -1
Option D matches this.
Concepts: regex search, case sensitivity vs i flag, String.prototype.search return values.
________________________________________
NEW QUESTION # 59
A developer writes the code below to return a message to a user attempting to register a new username. If the username is available, a variable named msg is declared and assigned a value on line 03.
function getAvailabilityMessage(item) {
if (getAvailability(item)) {
var msg = "Username available";
return msg;
}
}
- A. "Username available"
- B. "newUserName"
- C. undefined
- D. "msg is not defined"
Answer: A
Explanation:
The correct answer is C.
When getAvailability(item) returns true, the code inside the if block executes:
var msg = "Username available";
return msg;
The variable msg receives the string value:
"Username available"
Then that same value is returned from the function.
The key point is that var is function-scoped, not block-scoped. So msg belongs to the function scope of getAvailabilityMessage(). However, because the return msg; statement is inside the same if block, the function immediately returns the assigned string when the username is available.
Option A is incorrect because msg is defined before it is returned.
Option B is incorrect because "newUserName" is not assigned or returned anywhere in the function.
Option D would only happen if getAvailability(item) returned false, because then the function would finish without an explicit return value.
For the available username scenario, the verified answer is C.
NEW QUESTION # 60
A developer creates a simple webpage with an input field. When a user enters text in the inputfield and clicks the button, the actual value of the field must be displayed in the console.
Here is the HTML file content:
<input type =" text" value="Hello" name ="input">
<button type ="button" >Display </button>
The developer wrote the javascript codebelow:
Const button = document.querySelector('button');
button.addEvenListener('click', () => (
Const input = document.querySelector('input');
console.log(input.getAttribute('value'));
When the user clicks the button, the output is always "Hello".
What needs to be done make this code work as expected?
- A. Replace line 04 with console.log(input .value);
- B. Replace line 02 with button.addEventListener("onclick", function() {
- C. Replace line 03 with const input = document.getElementByName('input');
- D. Replace line 02 with button.addCallback("click", function() {
Answer: A
NEW QUESTION # 61
Given the code below:
01 setTimeout(() => {
02 console.log(1);
03 }, 1100);
04 console.log(2);
05 new Promise((resolve, reject) => {
06 setTimeout(() => {
07 reject(console.log(3));
08 }, 1000);
09 }).catch(() => {
10 console.log(4);
11 });
12 console.log(5);
What is logged to the console?
- A. 0
- B. 1
- C. 2
- D. 3
Answer: A
Explanation:
Comprehensive and Detailed Explanation From JavaScript Knowledge:
We must track synchronous code, setTimeout callbacks (macrotasks), and Promise rejection handling (microtasks).
Step-by-step:
Synchronous code first:
Line 01-03: Schedules a timeout at 1100 ms: logs 1 (later).
Line 04: console.log(2); → logs 2.
Lines 05-09: Construct a new Promise.
The executor runs immediately.
Inside it, another setTimeout is set for 1000 ms:
setTimeout(() => {
reject(console.log(3));
}, 1000);
Line 09-11: .catch(() => { console.log(4); }) attached to the promise.
Line 12: console.log(5); → logs 5.
So after all synchronous code, the console has:
2
5
At 1000 ms: inner setTimeout fires
The callback:
() => {
reject(console.log(3));
}
Inside:
console.log(3) runs first, logging 3.
console.log(3) returns undefined.
Then reject(undefined) is called.
So at about 1000 ms, we log:
3
When the promise is rejected:
The .catch handler is scheduled as a microtask.
After the current macrotask (the timeout callback) completes, the microtask queue runs.
Thus .catch(() => { console.log(4); }) runs shortly after, in the same 1000 ms tick.
So immediately after 3, the catch handler logs:
4
Now the logs in order are:
2
5
3
4
At 1100 ms: outer setTimeout fires
The callback from line 01 runs:
console.log(1);
Logs: 1.
Final log order:
2 (line 4, sync)
5 (line 12, sync)
3 (1000 ms timeout, then inside logs before reject)
4 (promise catch microtask after rejection)
1 (1100 ms timeout)
Concatenated: 25341.
Therefore, the correct option is:
Study Guide / Concept Reference (no links):
Event loop: call stack, macrotask queue (timers), microtask queue (promises) setTimeout scheduling and ordering Promise rejection, .catch, and microtasks Evaluation order of function arguments (reject(console.log(3)))
________________________________________
NEW QUESTION # 62
A developer wrote the following code to test a sum3 function that takes in an array of numbers and returns the sum of the first three numbers in the array. The test passes:
01 let res = sum3([1, 2, 3]);
02 console.assert(res === 6);
03
04 res = sum3([1, 2, 3, 4]);
05 console.assert(res === 6);
A different developer made changes to the behavior of sum3 to instead sum all of the numbers present in the array.
Which two results occur when running the test on the updated sum3 function?
- A. The line 02 assertion passes.
- B. The line 05 assertion fails.
- C. The line 05 assertion passes.
- D. The line 02 assertion fails.
Answer: A,B
Explanation:
New behavior: sum3 now returns the sum of all elements.
Line 01: sum3([1, 2, 3]) → 1 + 2 + 3 = 6
Assertion on line 02: res === 6 → passes.
Line 04: sum3([1, 2, 3, 4]) → 1 + 2 + 3 + 4 = 10
Assertion on line 05: res === 6 → 10 === 6 is false, so the assertion fails.
So:
Line 02 assertion passes → D.
Line 05 assertion fails → C.
NEW QUESTION # 63
Given code below:
setTimeout (()=> (
console.log(1);
). 0);
console.log(2);
New Promise ((resolve, reject )) = > (
setTimeout(() => (
reject(console.log(3));
). 1000);
)).catch(() => (
console.log(4);
));
console.log(5);
What is logged to the console?
- A. 1 2 5 3 4
- B. 2 5 1 3 4
- C. 2 1 4 3 5
- D. 1 2 43 5
Answer: B
NEW QUESTION # 64
Refer to the code below:
01 function myFunction(reassign) {
02 let x = 1;
03 var y = 1;
04
05 if (reassign) {
06 let x = 2;
07 var y = 2;
08 console.log(x);
09 console.log(y);
10 }
11
12 console.log(x);
13 console.log(y);
14 }
What is displayed when myFunction(true) is called?
- A. 2 2 2 2
- B. 2 2 1 2
- C. 2 2 1 1
- D. 2 2 undefined undefined
Answer: B
Explanation:
This question tests understanding of let (block scope) and var (function scope) in JavaScript.
Initial declarations in the function:
let x = 1; // line 2
var y = 1; // line 3
Here:
x is declared with let, so it is block-scoped to the function body.
y is declared with var, so it is function-scoped to the entire function.
Inside the if (reassign) block (and since reassign is true, we enter it):
if (reassign) {
let x = 2; // line 6
var y = 2; // line 7
console.log(x); // line 8
console.log(y); // line 9
}
Detailed behavior:
let x = 2; on line 6 creates a new block-scoped variable x that exists only inside the if block. It does not change the outer x declared on line 2.
var y = 2; on line 7 declares y with var again, but var is function-scoped. This effectively reassigns the same y defined on line 3 for the entire function. After this line, y is 2 everywhere in the function.
Now, inside the if block:
console.log(x); (line 8) logs the inner block-scoped x, which is 2.
console.log(y); (line 9) logs y, which is the function-scoped y that was set to 2.
So the first two outputs are:
2
2
After the if block, execution continues:
console.log(x); // line 12
console.log(y); // line 13
Outside the if block:
The block-scoped let x = 2; no longer exists; it was only visible inside the if block.
The outer let x = 1; (line 2) is still in scope and has not been changed.
Thus:
console.log(x); (line 12) logs the outer x, which is still 1.
console.log(y); (line 13) logs y which, due to var y = 2; inside the if, is now 2 for the whole function.
Therefore, when myFunction(true) is called, the output in order is:
2 (inner x in if)
2 (function-scoped y after reassignment)
1 (outer x after if)
2 (function-scoped y remains 2)
This corresponds to:
Answer : B (2 2 1 2)
JavaScript knowledge / study guide reference concepts:
let declarations and block scope
var declarations and function scope
Shadowing of variables with let inside a block
Re-declaration and reassignment of var within a function
Execution order of statements and console output
NEW QUESTION # 65
Teams at Universal Containers (UC) work on multiple JavaScript projects at the same time.
UC is thinking about reusability and how each team can benefit from the work of others.
Going open-source or public is not an option at this time.
Which option is available to UC with npm?
- A. Private registries are not supported by npm, but packages can be installed via git.
- B. Private packages can be scored, andscopes can be associated to a privateregistries.
- C. Private packages are not supported, but they can use another package manager likeyarn.
- D. Private registries are not supported by npm, but packages can be installed via URL.
Answer: B
NEW QUESTION # 66
A test searches for:
<button class="blue">Checkout</button>
But the actual HTML is:
<button>Checkout</button>
The test fails because it expects a class that no longer exists.
What type of test outcome is this?
- A. True negative
- B. False positive
- C. True positive
- D. False negative
Answer: D
Explanation:
________________________________________
Comprehensive and Detailed Explanation From Exact Extract JavaScript Knowledge Definitions:
False negative → The test reports a failure even though the feature actually works.
False positive → The test reports success when it should not.
True positive → Correctly identifies something is working.
True negative → Correctly identifies something is not working.
In this scenario:
The checkout button does exist, so the feature works.
The test fails incorrectly, because it is checking for the wrong selector.
That is the definition of a false negative.
________________________________________
JavaScript Knowledge Reference (text-only)
Test outcome classification: false negative = feature works but test fails.
NEW QUESTION # 67
Refer tofollowing code:
class Vehicle {
constructor(plate) {
This.plate =plate;
}
}
Class Truck extends Vehicle {
constructor(plate, weight) {
//Missing code
This.weight = weight;
}
displayWeight() {
console.log('The truck ${this.plate} has a weight of${this.weight} lb.');}} Let myTruck = new Truck('123AB', 5000); myTruck.displayWeight(); Which statement should be added to line 09 for the code to display 'The truck 123AB has a weight of 5000lb.'?
- A. super(plate);
- B. Super.plate =plate;
- C. Vehicle.plate = plate;
- D. This.plate =plate;
Answer: A
NEW QUESTION # 68
Which statement can a developer apply to increment the browser's navigation history without a page refresh?
Which statement can a developer apply to increment the browser's navigation history without a page refresh?
- A. window.history.pushState(newStateObject);
- B. window.history.pushStare(newStateObject, ' ', null);
- C. window.history.replaceState(newStateObject,'', null);
- D. window.history.state.push(newStateObject);
Answer: C
NEW QUESTION # 69
for (let number = 2; number <= 5; number += 1) {
// faster code statement here
}
Which statement meets the requirements to log an error when the Boolean statement evaluates to false?
- A. assert(number + 2 === 0);
- B. console.error(number + 2 === 0);
- C. console.classy(number + 2 === 0);
- D. console.assert(number + 2 === 0);
Answer: D
Explanation:
console.assert(condition, message?) logs an assertion error if condition is falsy.
To log an error when number + 2 === 0 is false, use:
console.assert(number + 2 === 0);
Other options are invalid or do not behave as described: console.error always logs, assert alone is not a built-in browser global, and console.classy doesn't exist.
________________________________________
NEW QUESTION # 70
Refer to the following code:
Let obj ={
Foo: 1,
Bar: 2
}
Let output =[],
for(let something in obj{
output.push(something);
}
console.log(output);
What is the output line 11?
- A. [1,2]
- B. ["bar","foo"]
- C. ["foo:1","bar:2"]
- D. ["foo","bar"]
Answer: D
NEW QUESTION # 71
bar, awesome is a popular JavaScript module. the versions publish to npm are:
Teams at Universal Containers use this module in a number of projects. A particular project has thepackage, json definition below.
A developer runs this command: npm install. Which version of bar .awesome is installed?
- A. The command fails, because version 130 is not found
- B. 1.3.1
- C. 1.4.0
- D. 1.3.5
Answer: D
NEW QUESTION # 72
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