- Set `react` and `react-dom` as peerDeps for all `lib` packages needing them
- Set `react` and `react-dom` as peerDeps + optional tag for all `addon` packages needing them
- Set `react` and `react-dom` as regular deps for all non react apps
- Remove `react` and `react-dom` from root `package.json`
- Set a fixed version of `react` in all examples
Also:
- Use "^16.8.0 || ^17.0.0" version range as some packages need React Hooks
`react` and `react-dom` should always be peer dependencies of packages that provide react components to ensure that there's a single instance of those.
Plus, all packages depending on a package with `react` as peerDep should also have it as peerDeps (transitive peer dependencies) or as deps.
Finally, packages in `examples/*` are "end" packages using Storybook so they must provide `react` and `react-dom` in their deps/devDeps
`@storybook/semver` is a browser friendly fork of `semver`.
We use it to avoid issue with IE11 as classic "compiled" `semver` is now compatible with it.
If we just recompile `semver` from `node_modules` it ends with a package that `require('core-js')` but `core-js` is not listed in the dependency. And so Yarn 2 throw an error.
So to avoid that we need to use a "proper" dependency which is `semver` recompile and with all needed dependencies in its package.json.
When testing Yarn 2 compatibility of Storybook CLI, we are using Yarn 2 in fixture directories inside a Yarn 1 workspace.
To access local versions of `@storybook` packages we use Yarn 2 `portal` protocol (see berryfy_package_json.js). However, it looks like CRA is not playing well with `portal` protocol and is throwing this kind of error: `Relative imports outside of src/ are not supported.`.
As new E2E tests will be soon available, I just removed the CRA tests instead of trying to hack them a bit more.
These fixtures are used to check that `sb init` is properly initializing SB in the fixture context so SB config (and stories) shouldn't be already in the fixture.
Moreover, fixtures were using outdated `config.js` file and a new `main.js` config file is added during initialization causing SB build to fail with:
```
ERR! Error: You have both a "main" and a "config". Please remove the "config" file from your configDir
```
These tests mimic the ones done to test SB CLI with "classic" yarn.
However, some magic setup and `package.json` customization are needed in order to make Yarn 2 works inside a Yarn v1 workspace.
