fix(NodePart): factory method created to help us when creating NodePart introduced due to scope hoisting problem with ParcelJS

[Stradivario]

Original Issue ParcelJS

Description

The problem here is that when compiled this part of code remains the same without export referencing him to the module scope

Typescript

itemPart = new NodePart(this.options);

Javascript

itemPart = new NodePart(this.options);

Instead it should be

itemPart = new exports.NodePart(this.options);

The case here is that i am getting the following error

Uncaught ReferenceError: NodePart is not defined

Type of change

• Bug fix
• Not introducing any existing change with existing API

Checklist:

• Implement factory method creating new NodeParts

Example repository of the problem:

https://github.com/Stradivario/parcel-scope-hoisting

Regards! :)

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[Stradivario]

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[Stradivario]

I think this issue is related with how typescript compile this part of the code.
If it is working with exports.NodePart manually added why TS decide to not catch this reference ?

[justinfagnani]

This isn't a bug with lit-html, and adds unnecessary lines of code. We should wait for the bugfix in Parcel.

[Stradivario]

This isn't a bug with lit-html, and adds unnecessary lines of code. We should wait for the bugfix in Parcel.

I understand!

What i cannot understand is why typescript doesn't put exports.NodePart in front since it does it in some other cases ? Is this a bug with Typescript ?

Regards!

[Stradivario]

Other strange thing is this

When typescript compile es6 commonjs class for example:

export class NodePart {}

Will be compiled to:

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
class NodePart {
}
exports.NodePart = NodePart;
//# sourceMappingURL=index.js.map

What it works ?!?

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.NodePart = class NodePart {
}
//# sourceMappingURL=index.js.map

Do you know why they decided this approach ?
Since even with that simple change everything work as expected without this pull request ?

[Stradivario]

@justinfagnani closing since Parcel Team confirmed that it is a bug in the renaming when tree shaking the whole bundle.

parcel-bundler/parcel#3172 (comment)

Thank you for your fast answer and correct resolution of the problem!

Regards!