TypeScript support for config

[trustedtomato]

Config can be given through a JSON/YAML file, and through init({config: {backend: {name: "git-gateway"}, ...}}) as shown here.
Right now, the @sveltia/cms is not typed at all, which is fair, given that Decap CMS and as such Sveltia CMS too, is probably mostly used through the JSON/YAML config.
However, providing it through the init function has two major benefits:

• It can be typed (using which typos can be easily avoided, and it's a neat way of providing docs, too): TypeScript type definitions decaporg/decap-cms#2926
• The config can be modularized: Modularize config.yml decaporg/decap-cms#3624

Therefore I'm suggesting the typing of the package. Inspiration could be taken from here: https://github.com/decaporg/decap-cms/blob/main/packages/decap-cms-core/index.d.ts

[kyoshino]

Will do at some point. A workaround can be found in #215 but it’s not perfect as Sveltia CMS has added some new options.

[kyoshino]

Actually we already have JSDoc type definitions. I’ll try to generate .d.ts from the typedef.js like Sveltia UI does.

[kyoshino]

Type generation is working well locally. I’ll make sure all types are up-to-date according to the Decap CMS document.

[kyoshino]

It turns out index.d.ts in Netlify/Decap CMS is overall incomplete, and instead many undocumented options are included. There are several open issues, and I’ll get them covered. (But not sure about the last one, because I don’t care about undocumented internal usage.)

• Keeping internal and external types in sync decaporg/decap-cms#4987
• type definition does not match code for registerWidget? decaporg/decap-cms#5970
• Custom Widget type not assignable to CmsFieldBase - Typescript decaporg/decap-cms#6527
• Typescript: Object literal may only specify known properties, and 'min' does not exist in type decaporg/decap-cms#6800
• Types for registerWidget don't match the implementation decaporg/decap-cms#7410

[kyoshino]

Shipped v0.63.1 with TypeScript support.

[trustedtomato]

Just checked now. Works great, thank you for the quick fix:)