Add types

[ChristianMurphy]

This currently has two major blockers

• TypeScript 3.7 with type assertion functions is not yet released
• A workaround needs to be found to name a function void

Once those are resolved, this will need:

• TSDocs
• Type tests

[ChristianMurphy]

/cc @Rokt33r any ideas around how to work around void being reserved?

[Rokt33r]

@ChristianMurphy https://github.com/sindresorhus/filenamify/blob/master/index.d.ts
This should be the solution!

[ChristianMurphy]

Thanks @Rokt33r that resolved the issue.

[ChristianMurphy]

Blockers have been resolved, this is now ready for review.

[ChristianMurphy]

@wooorm note that this also includes a couple JS changes suggested by XO.

[Rokt33r]

LGTM

[wooorm]

I wanted to release this but rm -rf node_modules; npm i; npm t fails for me:

> unist-util-assert@1.0.4 test-types /Users/tilde/Downloads/oss/unist-util-assert
> dtslint types

Error: Cannot find module '/Users/tilde/.dts/typescript-installs/3.7/node_modules/typescript'
Require stack:
- /Users/tilde/Downloads/oss/unist-util-assert/node_modules/dtslint/bin/lint.js
- /Users/tilde/Downloads/oss/unist-util-assert/node_modules/dtslint/bin/index.js

(on Node 13.0.1 and npm 6.13.0). Any thoughts on why this is happening?

[ChristianMurphy]

I've run into this before.
Usually it means something is off with the dtslint cache.
Running rm -rf ~/.dts/typescript-installs/3.7 ~/.dts/typescript-installs/next resolved the issue for me.

[wooorm]

alright, released!