"Convert to ES6 module" not working with IIFE pattern

[mjbvz]

From @osya on May 21, 2018 8:59

• VSCode Version: 1.23.1
• OS Version: Windows 10 Pro x64

Steps to Reproduce:

1. Create a file test_file.js with the following content:

var path = require('path');

(function () {
    var path = require('path');
}());

Click lightbulb and select "Convert to ES6 module" then the 1st require transforms to the import path from "path";. It is correct. Then comment 1st require and click lightbulb and select "Convert to ES6 module" for the 2nd require. 2nd require doesn't converted to the import path from "path";. ES6 imports must be at the top level of your JavaScript files. So, I suppose, for require in IIFE there should be NO option "Convert to ES6 module"

Copied from original issue: microsoft/vscode#50205

[mjbvz]

Yes, I think not converting the inner require is correct since imports can only appear at the top level in a program.

In VS Code insiders, I do not see the convert to es6 suggestion on the inner require:

[osya]

@mjbvz , may be you just need to wait a little bit. There is a screenshot with existing "Convert to ES6 module" suggestion for require in the IIFE

[DanielRosenwasser]

(As an aside, could you tell us a bit more about why this IIFE is being used?)

[mhegazy]

@osya this last report should be fixed by #24101.

[osya]

@DanielRosenwasser I use IIFE for the following two reasons:

1. I 'use strict';. Then without IIFE jshint generates warning: "Use the function form of "use strict". (W097)". So, the 1st reason for using IIFE is to avoid this warning.
2. Resharper's warning "Property or global variable ... is possibly never assigned"

[ghost]

@osya This was fixed recently in #24101, you may need to install typescript@next to stop seeing the suggestion in inner scopes.