stylelint/src/rules/at-rule-name-newline-after/index.js

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import {
  ruleMessages,
  validateOptions,
  whitespaceChecker,
} from "../../utils"
import { atRuleNameSpaceChecker } from "../at-rule-name-space-after"

export const ruleName = "at-rule-name-newline-after"

export const messages = ruleMessages(ruleName, {
  expectedAfter: (name) => `Expected newline after at-rule name \"${name}\"`,
  rejectedAfter: (name) => `Unexpected newline after at-rule name \"${name}\"`,
})

export default function (expectation) {
  const checker = whitespaceChecker("newline", expectation, messages)
  return (root, result) => {
    const validOptions = validateOptions(result, ruleName, {
      actual: expectation,
      possible: [
        "always",
        "always-multi-line",
      ],
    })
    if (!validOptions) { return }

    atRuleNameSpaceChecker({
      root,
      result,
      locationChecker: checker.afterOneOnly,
      checkedRuleName: ruleName,
    })
  }
}