Rule's Options Schema

[azu]

Currently, textlint does not check the actual option.

So, the user pass an invalid option and does not show any errors.

For example, textlint-rule-en-capitalization support folllowing options.

{
    "rules": {
        "en-capitalization": {
             // allow lower-case words in Header
             "allowHeading": true,
             // allow lower-case words in Image alt
             "allowFigures": true,
             // allow lower-case words in ListItem
             "allowLists": true,
             // allow lower-case words in anywhere
             "allowWords": []
         }
    }
}

However, the user passed an invalid option like "allowHead: true and textlint does not show any error.

{
    "rules": {
        "en-capitalization": {
             "allowHead": true
         }
    }
}

textlint does not know that the rule has what options.

Rule Options Schema

To resolve this, we need to introduce rule's options schema.
ESLint has similar one - Options Schemas.
Each rule defines JSON Schema and ESLint use it for validation.

As a various rule author, I do not want to write JSON Schema by handwriting 😞
Instead of it, We can write a rule in TypeScript and We can use Type for JSON Schema.

I've created babel-plugin-textlint-scripts.
This babel plugin converts TypeScript type to JSON Schema.

In

export type Options = {
    str_key: string;
};
const report = () => {
    return {};
};
export default report;

Out

const report = () => {
  return {};
};

export default report;
export const meta = {
  name: "@textlint/babel-plugin-textlint-scripts",
  description: "A babel plugin for textlint-scripts.",
  homepage: "https://github.com/textlint/babel-plugin-textlint-scripts",
  schema: {
    "type": "object",
    "properties": {
      "str_key": {
        "type": "string"
      }
    },
    "additionalProperties": false,
    "required": ["str_key"],
    "$schema": "http://json-schema.org/draft-07/schema#"
  }
};

This plugin will help us to integrate Options schema.

Of course, we can write JSON by handwriting.

TODO

• Define spec for JSON schema and meta object
• Implement validation logics into textlint
  • Should we implment this into @textlint/core?

[azu]

Recently, I've created @textlint/config-loader package.
We create a new @textlint/config-validator package that validates the rule option with the config.

Pasado code

import { loadConfig } from "@textlint/config-loader";
import { validate } from "@textlint/config-validator";


(async function () {
    const configResult = await loadConfig({
        cwd: process.cwd()
    });
    if (!configResult.ok) {
        console.error(configResult.error.message, configResult.error.errors);
        return;
    }
    // config includes .textlint opsions and rule instance
    const validateResult = await validate(configResult.config);
    if(!result.ok) {
        console.error(validateResult.error.message, validateResult.error.errors);
        return;
    }
});