Namespaces with ECMAScript 6 classes

Question

I'm trying to define a class inside the namespace TEST using ECMAScript 6. With "old" Javascript I did this

var TEST=TEST || {};
TEST.Test1 = function() {
}

now I'm trying the following

var TEST=TEST || {};
class TEST.Test2 {

}

but I get an error over the dot between TEST and Test2

Uncaught SyntaxError: Unexpected token

What's the correct way to do what I'm trying to accomplish, without using transpilers but only with native browser javascript?

Answer 1

Just as for functions, there are class declarations and class expressions. You can use a class expression instead and assign the result to TEST.Test1:

TEST.Test1 = class { // or `TEST.Test1 = class Test1 {`

};

Answer 2

Generally this is exactly what ES6 modules are for:

export class Test2 { ... }

...

import * as TEST from './test';

new TEST.Test2(...)

For a single file with class definitions, it can be

const TEST = window.TEST || {};

{
  class Test2 { ... }
  ...

  Object.assign(TEST, { Test2, ... });
}

Another option is using class expressions (as another answer already explained).