fix(fela): get rid of const enum in typings

[layershifter]

Description

Currently fela typings have a single use of const enum and it means that you cannot to build a project with --isolatedModules. See for more details: microsoft/fluent-ui-react#613

Actually, this change is very important because const enums are not supported by @babel/preset-typescript, too.

I added typings for fela-utils as this package contains constants that can be used by consumers.

You should use a union type of literals (string or number) instead.

microsoft/TypeScript#20703 (comment)

Packages

• fela

Versioning

Actually, it's a breaking change that requires a major bump because you will not able to use TSubscribeMessageType as value.

Before

import { TSubscribeMessageType } from 'fela'

const type = TSubscribeMessageType.rule

After

import { RULE_TYPE } from 'fela-utils'

const type = RULE_TYPE 

Checklist

Quality Assurance

You can also run yarn run check to run all 4 commands at once.

• The code was formatted using Prettier (yarn run format)
• The code has no linting errors (yarn run lint)
• All tests are passing (yarn run test)
• There are no flow-type errors (yarn run flow)

[robinweser]

Hmm so we should have a major version update "just" for those types? Feels somewhat wrong to me, but makes sense...

[layershifter]

Hmm so we should have a major version update "just" for those types?

For me: it's fine to ship it as patch 😸

However, if someone really used TSubscribeMessageType as value, it will be a breaking change 🤔 Have mixed feelings about it.

[robinweser]

Yeah me too. But as someone who does not use TypeScript, this feels super wrong as the actual code is not breaking or anything.
Let's try a patch and see what happens - maybe we learn it should be done with majors next time 🙆‍♂️