Salesforce Updated JavaScript-Developer-I Exam Questions and Answers by hermione

The correct answer is D .

Semantic versioning usually follows this format:

MAJOR.MINOR.PATCH

For the version:

1.1.3

The parts are:

1 = MAJOR

1 = MINOR

3 = PATCH

A package version should be updated based on the type of change:

MAJOR version changes when there are breaking changes.

MINOR version changes when new features are added in a backward-compatible way.

PATCH version changes when backward-compatible bug fixes are added.

The question says the developer added new features that do not break backward compatibility . That means the minor version should increase.

Starting version:

1.1.3

Increase the minor version from 1 to 2, and reset the patch version to 0:

1.2.0

Why the other options are incorrect:

A. 1.2.3 is incorrect because when the minor version increases, the patch version should reset to 0.

B. 1.1.4 is incorrect because that would represent a patch update, usually for bug fixes, not new features.

C. 2.0.0 is incorrect because that would represent a major version update, usually for breaking changes.

D. 1.2.0 is correct because it represents a backward-compatible feature release.

Therefore, the verified answer is D .

The question specifies:

The library “uses events and callbacks to start the server”.

We want to “set up an event and start the web server”.

Option C:

server((port) = > { console.log( ' Listening on ' , port); });

This:

Calls server(...), which (by design in such libraries) typically starts the web server.

Passes a callback function that receives port when the server is ready.

Inside the callback, it logs " Listening on < port > " .

This matches the “events and callbacks” description: the callback is invoked when the server has started listening.

Why others are incorrect:

A. server.on( ' connect ' , ...)

Assumes server is an event emitter instance with a ' connect ' event, which is not given. Also, this line alone would not start the server.

B. server.start();

Assumes a start method exists; the question says the library “uses events and callbacks to start,” implying invocation with a callback, not a plain start() call.

D. server();

Might start the server, but does not “set up an event” or callback to know when or where it is listening.

Therefore, C aligns with the described usage.

Concepts: callback-based APIs, starting servers with callbacks, event/callback style vs simple method calls.

The correct answer is D , because JavaScript executes synchronous code first, while the code after await runs later after the Promise resolves.

The execution order is:

console.log(2);

This runs first, so JavaScript logs:

2

Then this line runs:

asyncCall();

The asyncCall() function starts executing. Inside it, JavaScript reaches:

await delay(1000);

The delay(1000) function returns a Promise that resolves after 1000 milliseconds:

return new Promise(resolve = > {

setTimeout(resolve, delay);

});

Because await pauses the rest of the asyncCall() function, this line does not run immediately:

console.log(1);

Instead, JavaScript continues executing the remaining synchronous code outside the async function:

console.log(3);

So JavaScript logs:

3

After approximately 1000 milliseconds, the Promise returned by delay(1000) resolves. Then the paused async function continues and runs:

console.log(1);

So JavaScript logs:

1

Final console output:

2

3

1

Important JavaScript concepts involved:

An async function always returns a Promise.

The await keyword pauses execution only inside the async function where it appears.

Code outside the async function continues running normally.

setTimeout() schedules its callback to run later, after the current synchronous code has finished.

Therefore, the verified answer is D. 2 3 1 .

Evaluate each test:

A. sum3([1, ' 2 ' ])

Array length is 2 → line 4: arr[0] + arr[1] → 1 + ' 2 ' → ' 12 ' (string).

Assertion: ' 12 ' == 12 is true (type coercion). However, this “test” is not logically correct: a numeric sum function should not be expected to return ' 12 ' as a string. It passes only because of weak equality coercion, so it is not a good/valid test of correct behavior.

B. sum3([ ' hello ' , 2, 3, 4])

Length ≥ 3 → line 5: ' hello ' + 2 + 3 → ' hello2 ' + 3 → ' hello23 ' .

' hello23 ' === NaN is always false because NaN is never equal to anything, not even itself. This assertion fails and also misunderstands how NaN comparisons work.

C. sum3([-3, 2])

Length 2 → -3 + 2 = -1.

Assertion: -1 === -1 → true. This is a correct and meaningful test.

D. sum3([0])

Length 1 → returns arr[0] → 0.

Assertion: 0 === 0 → true. Also a correct and meaningful test.

Therefore, the valid and logically correct tests here are C and D.