feat(lib): allow strong typing for icons

[minenwerfer]

This PR adds a const constraint to the icons array exported by src/icons.ts, so the Typescript compiler will emit a much more useful declaration file which can later be used to strictly type valid icon names. It also exports a new PhosphorIcon type.

Instead of emitting this in `dist/icons.d.ts:

export declare const icons: ReadonlyArray<IconEntry>;

With this PR the following will be emitted:

export declare const icons: readonly [{
    readonly name: "address-book";
    readonly pascal_name: "AddressBook";
    readonly categories: readonly [IconCategory.COMMUNICATION];
    readonly figma_category: FigmaCategory.COMMUNICATION;
    readonly tags: readonly ["contacts", "roledex"];
    readonly codepoint: 59128;
    readonly published_in: 1.3;
    readonly updated_in: 1.3;
}, // ...
]

Now the following becomes possible:

import { PhosphorIcon } from '@phosphor-icons/core'
declare const myComponent: (props: { icon: PhosphorIcon['name'] }) => any

myComponent({
  // this prop is strongly typed
  icon: 'address-book'
})

I believe this will hardly break anything. If it does, a separated export can be added.

[rektdeckard]

This seems fine, and is a nice improvement. I'm curious about devtime performance — does LSP still feel snappy with a hefty mapped type like PhosphorIcon? I have heard that big unions really thrash typechecking. Will give it a try later.

[minenwerfer]

This seems fine, and is a nice improvement. I'm curious about devtime performance — does LSP still feel snappy with a hefty mapped type like PhosphorIcon? I have heard that big unions really thrash typechecking. Will give it a try later.

It feels normal in Neovim + LSP. Not super fast, not super slow either.

[rektdeckard]

Feels good on my end. Please also update the codegen script that creates the icons.ts file, then run the catalog script to emit the file rather than changing it manually:

https://github.com/phosphor-icons/core/blob/main/scripts/catalog.ts#L41-L107

[minenwerfer]

Feels good on my end. Please also update the codegen script that creates the icons.ts file, then run the catalog script to emit the file rather than changing it manually:

https://github.com/phosphor-icons/core/blob/main/scripts/catalog.ts#L41-L107

Sure, I think I missed that. Will commit later.

[minenwerfer]

@rektdeckard I just made a new commit, please review it.

[rektdeckard]

Thanks for the contrib!

[minenwerfer]

Thanks for merging my PR!
Could you please release this version on npm?

[rektdeckard]

I'm writing some additional docs, will publish this evening