stylelint/src/rules/declaration-bang-space-before/index.js

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import {
  ruleMessages,
  validateOptions,
  whitespaceChecker,
} from "../../utils"
import { declarationBangSpaceChecker } from "../declaration-bang-space-after"

export const ruleName = "declaration-bang-space-before"

export const messages = ruleMessages(ruleName, {
  expectedBefore: () => "Expected single space before \"!\"",
  rejectedBefore: () => "Unexpected whitespace before \"!\"",
})

export default function (expectation) {
  const checker = whitespaceChecker("space", expectation, messages)
  return (root, result) => {
    const validOptions = validateOptions(result, ruleName, {
      actual: expectation,
      possible: [
        "always",
        "never",
      ],
    })
    if (!validOptions) { return }

    declarationBangSpaceChecker({
      root,
      result,
      locationChecker: checker.before,
      checkedRuleName: ruleName,
    })
  }
}