no-constant-condition.js

/**
 * @author Flo Edelmann
 */
'use strict'

const { RuleTester } = require('eslint')
const rule = require('../../../lib/rules/no-constant-condition.js')

const tester = new RuleTester({
  parser: require.resolve('vue-eslint-parser'),
  parserOptions: { ecmaVersion: 6 }
})

tester.run('no-constant-condition', rule, {
  valid: [
    '<template><CustomButton v-if="a" /></template>',
    '<template><CustomButton v-if="a == 0" /></template>',
    '<template><CustomButton v-if="a == f()" /></template>',
    '<template><CustomButton v-other-directive="true" /></template>'
  ],
  invalid: [
    {
      code: '<template><CustomButton v-if="-2" /></template>',
      errors: [
        {
          messageId: 'unexpected',
          type: 'UnaryExpression',
          column: 31,
          endColumn: 33
        }
      ]
    },
    {
      code: '<template><CustomButton v-else-if="true" /></template>',
      errors: [
        {
          messageId: 'unexpected',
          type: 'Literal',
          column: 36,
          endColumn: 40
        }
      ]
    },
    {
      code: '<template><CustomButton v-if="1" /></template>',
      errors: [
        {
          messageId: 'unexpected',
          type: 'Literal',
          column: 31,
          endColumn: 32
        }
      ]
    },
    {
      code: '<template><CustomButton v-show="{}" /></template>',
      errors: [
        {
          messageId: 'unexpected',
          type: 'ObjectExpression',
          column: 33,
          endColumn: 35
        }
      ]
    },
    {
      code: '<template><CustomButton v-if="0 < 1" /></template>',
      errors: [
        {
          messageId: 'unexpected',
          type: 'BinaryExpression',
          column: 31,
          endColumn: 36
        }
      ]
    },
    {
      code: '<template><CustomButton v-if="0 || 1" /></template>',
      errors: [
        {
          messageId: 'unexpected',
          type: 'LogicalExpression',
          column: 31,
          endColumn: 37
        }
      ]
    }

    // failing in Node.js v8, because template literals are not supported there:
    // {
    //   code: '<template><CustomButton v-if="`foo`" /></template>',
    //   errors: [
    //     {
    //       messageId: 'unexpected',
    //       type: 'TemplateLiteral',
    //       column: 31,
    //       endColumn: 36
    //     }
    //   ]
    // },
    // {
    //   code: '<template><CustomButton v-if="``" /></template>',
    //   errors: [
    //     {
    //       messageId: 'unexpected',
    //       type: 'TemplateLiteral',
    //       column: 31,
    //       endColumn: 33
    //     }
    //   ]
    // }
  ]
})