Add config support for babel-plugin-relay/macro

[sgwilym]

Allows configuration options (e.g. artifactDirectory, schema) to be passed to usages of babel-plugin-relay/macro using experimental support in babel-macros. The options can be specified in any of the possible ways listed in the following URL: https://github.com/kentcdodds/babel-plugin-macros/blob/master/other/docs/author.md#config-experimental

Notably allows more complex configurations in projects created with create-react-app. In my case, I'd like to use an un-ejected CRA project with relay-compiler-language-typescript.

[sibelius]

can you also add an enable of the usage of this on docs?

[sgwilym]

@sibelius Added docs.

[kassens]

Thank you!

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[hughevans]

@sgwilym Do you have an example of an un-ejected CRA working with relay-compiler-language-typescript?

[sgwilym]

@hughevans I don't, but with the next release it should be straightforward. The only thing you should need to add is a config for babel-plugin-relay/macro, e.g. in package.json:

"babelMacros": {
    "relay": {
      "artifactDirectory": "./src/__generated__"
    }
  }

(and your relay-compiler command should also have the --language typescript and --artifactDirectory ./src/__generated__ flags).