Visual Studio Code autocomplete/IntelliSense not working properly for JavaScript

Question

It's not displaying the properties of an array like length etc.

I'm not sure if this is a problem or this is expected behavior of VScode's autocomplete/IntelliSense.

Do I need to install any extensions to make it work?

Edit:
On adding var or let before arr the autocomplete works fine normally but inside a function it doesn't work.

Eared

Answer 1

Check if the building extension TypeScript and JavaScript Language Features is enabled.

To check this, go to Extensions and search for @builtin TypeScript and JavaScript Language Features.

This should look something like this: [![vscode][1]][1]

Edit:

Also, check if you choosed the right language?

• -> CTRL (or CMD) + P
• -> > Change Language Mode
• -> JavaScript

Another thing I noticed: You have no var, let or const before the variable, see https://mcmap.net/q/1920476/-visual-studio-code-intellisense-not-working-for-node-js

Edit 2:

IntelliSense does not know what types the parameters have for functions. But you can use the @param annotation in the comment:

/**
 * 
 * @param {Array} arr 
 */
function a(arr) {
    arr.
}

For variables you can also use @type:

/** @type {Array} */
let a;

Radioelement

Yes @Radioelement this is enabled but still not working. – Eared

@at-in Choosed the right language? CTRL (or CMD) + P -> > Change Language Mode -> JavaScript – Radioelement

@at-in Another thing I noticed: You have no var, let or const before the variable, see https://mcmap.net/q/1920476/-visual-studio-code-intellisense-not-working-for-node-js – Radioelement

on adding let or var it works fine but inside a function it doesn't work. I'll edit my question a bit to explain this – Eared

Just a suggestion @Daniel, you should add the let/var thing in your answer since this is also a problem someone else might face. – Eared

What was the answer? I get the same issue. When I jump inside a function or method, the auto-completion won't be enabled. – Penates

Thanks man, big help was actually going crazy trying to fix this. – Costotomy

off topic: which font is that (Vscode)? @Radioelement – Tichonn

@Tichonn I think I used Fira Code in the screenshots – Radioelement

Answer 2

Go to Extensions and search for @builtin TypeScript and JavaScript Language Features. Try stopping and restarting this plugin and restart VS Code. Looks like a bug. This fixed it for me.

Stoplight

Answer 3

For me I just stop the TypeScript and JavaScript Language Features extension, and it works fine, maybe a bug or a conflict with other extensions I think

Novah

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