first-attribute-linebreak.js

/**
 * @fileoverview Enforce the location of first attribute
 * @author Yosuke Ota
 */
'use strict'

const utils = require('../utils')

module.exports = {
  meta: {
    type: 'layout',
    docs: {
      description: 'enforce the location of first attribute',
      categories: ['vue3-strongly-recommended', 'vue2-strongly-recommended'],
      url: 'https://eslint.vuejs.org/rules/first-attribute-linebreak.html'
    },
    fixable: 'whitespace',
    schema: [
      {
        type: 'object',
        properties: {
          multiline: { enum: ['below', 'beside', 'ignore'] },
          singleline: { enum: ['below', 'beside', 'ignore'] }
        },
        additionalProperties: false
      }
    ],
    messages: {
      expected: 'Expected a linebreak before this attribute.',
      unexpected: 'Expected no linebreak before this attribute.'
    }
  },
  /** @param {RuleContext} context */
  create(context) {
    /** @type {"below" | "beside" | "ignore"} */
    const singleline =
      (context.options[0] && context.options[0].singleline) || 'ignore'
    /** @type {"below" | "beside" | "ignore"} */
    const multiline =
      (context.options[0] && context.options[0].multiline) || 'below'

    const sourceCode = context.getSourceCode()
    const template =
      sourceCode.parserServices.getTemplateBodyTokenStore &&
      sourceCode.parserServices.getTemplateBodyTokenStore()

    /**
     * Report attribute
     * @param {VAttribute | VDirective} firstAttribute
     * @param { "below" | "beside"} location
     */
    function report(firstAttribute, location) {
      context.report({
        node: firstAttribute,
        messageId: location === 'beside' ? 'unexpected' : 'expected',
        fix(fixer) {
          const prevToken = template.getTokenBefore(firstAttribute, {
            includeComments: true
          })
          return fixer.replaceTextRange(
            [prevToken.range[1], firstAttribute.range[0]],
            location === 'beside' ? ' ' : '\n'
          )
        }
      })
    }

    return utils.defineTemplateBodyVisitor(context, {
      VStartTag(node) {
        const firstAttribute = node.attributes[0]
        if (!firstAttribute) return

        const lastAttribute = node.attributes[node.attributes.length - 1]

        const location =
          firstAttribute.loc.start.line === lastAttribute.loc.end.line
            ? singleline
            : multiline
        if (location === 'ignore') {
          return
        }

        if (location === 'beside') {
          if (node.loc.start.line === firstAttribute.loc.start.line) {
            return
          }
        } else {
          if (node.loc.start.line < firstAttribute.loc.start.line) {
            return
          }
        }
        report(firstAttribute, location)
      }
    })
  }
}