no-mutating-props.js

/**
 * @fileoverview disallow mutation of component props
 * @author 2018 Armano
 */
'use strict'

// ------------------------------------------------------------------------------
// Requirements
// ------------------------------------------------------------------------------

const rule = require('../../../lib/rules/no-mutating-props')
const RuleTester = require('eslint').RuleTester

// ------------------------------------------------------------------------------
// Tests
// ------------------------------------------------------------------------------

const ruleTester = new RuleTester({
  parser: require.resolve('vue-eslint-parser'),
  parserOptions: {
    ecmaVersion: 2020,
    sourceType: 'module'
  }
})

ruleTester.run('no-mutating-props', rule, {
  valid: [
    {
      filename: 'test.vue',
      code: `
        <template>
          <div>
            <div v-if="foo"></div>
            <div v-if="prop1 = [1, 2]"></div>
            <div v-if="prop2++"></div>
            <div v-text="prop3.shift()"></div>
            <div v-text="prop4.slice(0).shift()"></div>
            <div v-if="this.prop5 = [1, 2] && this.someProp"></div>
            <div v-if="this.prop6++ && this.someProp < 10"></div>
            <div v-text="this.prop7.shift()"></div>
            <div v-text="this.prop8.slice(0).shift()"></div>
          </div>
        </template>
        <script>
          export default {
            props: ['foo']
          }
        </script>
      `
    },
    {
      filename: 'test.vue',
      code: `
        <template>
          <div>
            <input v-model="prop1.text">
            <input v-model="prop2">
            <input v-model="this.prop3.text">
            <input v-model="this.prop4">
            <input :value="prop5.text" @input="$emit('input', $event.target.value)">
            <div v-for="prop5 of data">
              <input v-model="prop5">
            </div>
            <div v-for="(prop6, index) of data">
              <input v-model="prop6">
            </div>
            <template v-for="(test, index) of data">
              <template v-for="(prop6, index) of data">
                <input v-model="prop6">
                <div v-text="prop6.shift()"></div>
              </template>
            </template>
          </div>
        </template>
        <script>
          export default {
            props: ['prop5', 'prop6', 'prop7', 'prop8']
          }
        </script>
      `
    },
    {
      filename: 'test.vue',
      code: `
        <template>
          <div>
            <input v-model="prop1.text">
            <input v-model="prop2">
            <input v-model="this.prop3.text">
            <input v-model="this.prop4">
          </div>
        </template>
        <script>
          export default {
            props: ['prop5', 'prop6', 'prop7', 'prop8']
          }
        </script>
      `
    },
    {
      filename: 'test.vue',
      code: `
        <template>
          <div>
            <input v-for="i in prop.slice()">
            <input v-for="i in prop.foo.slice()">
          </div>
        </template>
        <script>
          export default {
            props: ['prop']
          }
        </script>
      `
    },
    {
      filename: 'test.vue',
      code: `
        <script>
          export default {
            props: {
              todo: {
                type: Object,
                required: true
              },
              items: {
                type: Array,
                default: []
              }
            },
            methods: {
              openModal() {
                this.$emit('someEvent', this.todo)
                const a = this.items.slice(0).push('something') // no mutation because of \`slice(0)\`
              }
            }
          }
        </script>
      `
    },
    {
      filename: 'test.vue',
      code: `
        <template>
          <div v-if="prop">
            <div v-for="prop in data">
              <MyComp @click="prop.foo++"></MyComp>
              <input v-model="prop">
            </div>
            <input v-model="prop()">
            <input v-model="foo">
            <input @click="prop().foo++">
            <input v-model="foo[this]">
            <input v-model="foo[this.prop]">
            <input v-model="this">
            <MyComp @click="bar = {prop: foo++}"></MyComp>
          </div>
        </template>
        <script>
          export default {
            props: ['prop'],
            methods: {
              onKeydown() {
                const vm = this
                foo.prop = 1
                vm()()()
                vm.prop()()
                prop++
                prop = 1
                const bar = {prop: foo}
                prop[this] ++
              }
            }
          }
        </script>
      `
    },
    {
      filename: 'test.vue',
      code: `
        <template>
          <div>
            <button @click="foo++"></button>
            <button @click="foo+=1"></button>
            <button @click="foo.push($event)"></button>
            <input v-model="foo">
            <input v-model="this.foo">
          </div>
        </template>
      `
    },

    // setup
    {
      filename: 'test.vue',
      code: `
        <script>
          export default {
            setup(props) {
              props ++
              props = 1
              props.push(1)
            }
          }
        </script>
      `
    },
    {
      filename: 'test.vue',
      code: `
        <script>
          export default {
            setup({a}) {
              a ++
              a = 1
            }
          }
        </script>
      `
    },
    {
      filename: 'test.vue',
      code: `
        <script>
          export default {
            setup({...props}) {
              props ++
              props = 1
              props.push(1)
            }
          }
        </script>
      `
    },
    {
      filename: 'test.vue',
      code: `
        <script>
          export default {
            ssss(props) {
              props.a ++
            }
          }
        </script>
      `
    },
    {
      filename: 'test.vue',
      code: `
        <script>
          export default {
            setup(props) {
              const a = props.a
            }
          }
        </script>
      `
    },
    {
      filename: 'test.vue',
      code: `
        <script>
          export default {
            setup() {
              props.a++
            }
          }
        </script>
      `
    },
    {
      filename: 'test.vue',
      code: `
        <script>
          export default {
            setup(...props) {
              props.a++
            }
          }
        </script>
      `
    },
    {
      filename: 'test.vue',
      code: `
        <script>
          export default {
            setup([props]) {
              props.a++
            }
          }
        </script>
      `
    },
    {
      filename: 'test.vue',
      code: `
        <script>
        // not <script setup>
        const {value} = defineProps({
          value: Object,
        })
        value.value++
        </script>
      `
    },
    {
      filename: 'test.vue',
      code: `
        <script>
        // not <script setup>
        const {value} = defineProps({
          value: Object,
        })
        value.value++
        </script>
        <script setup>
        value.value++
        </script>
      `
    },
    {
      // https://github.com/vuejs/eslint-plugin-vue/issues/1579
      filename: 'test.vue',
      code: `
      <script>
        export default {
          props: ['prop'],
          setup(props) {
            props.prop.sortAscending()
          }
        }
      </script>`
    }
  ],

  invalid: [
    {
      filename: 'test.vue',
      code: `
        <template>
          <div>
            <div v-if="prop1 = [1, 2]"></div>
            <div v-if="prop2++"></div>
            <div v-text="prop3.shift()"></div>
            <div v-text="prop4.slice(0).shift()"></div>
            <div v-if="this.prop5 = [1, 2] && this.someProp"></div>
            <div v-if="this.prop6++ && this.someProp < 10"></div>
            <div v-text="this.prop7.shift()"></div>
            <div v-text="this.prop8.slice(0).shift()"></div>
          </div>
        </template>
        <script>
          export default {
            props: ['prop1', 'prop2', 'prop3', 'prop4', 'prop5', 'prop6', 'prop7', 'prop8']
          }
        </script>
      `,
      errors: [
        {
          message: 'Unexpected mutation of "prop1" prop.',
          line: 4
        },
        {
          message: 'Unexpected mutation of "prop2" prop.',
          line: 5
        },
        {
          message: 'Unexpected mutation of "prop3" prop.',
          line: 6
        },
        {
          message: 'Unexpected mutation of "prop5" prop.',
          line: 8
        },
        {
          message: 'Unexpected mutation of "prop6" prop.',
          line: 9
        },
        {
          message: 'Unexpected mutation of "prop7" prop.',
          line: 10
        }
      ]
    },
    {
      filename: 'test.vue',
      code: `
        <template>
          <div>
            <div v-text="prop1?.shift?.()"></div>
            <div v-text="prop2?.slice?.(0)?.shift?.()"></div>
            <div v-if="this?.prop3"></div>
            <div v-if="this?.prop4 < 10"></div>
            <div v-text="this?.prop5?.shift?.()"></div>
            <div v-text="this?.prop6?.slice?.(0)?.shift?.()"></div>
          </div>
        </template>
        <script>
          export default {
            props: ['prop1', 'prop2', 'prop3', 'prop4', 'prop5', 'prop6']
          }
        </script>
      `,
      errors: [
        'Unexpected mutation of "prop1" prop.',
        'Unexpected mutation of "prop5" prop.'
      ]
    },
    {
      filename: 'test.vue',
      code: `
        <template>
          <div>
            <div v-text="(prop1?.shift)?.()"></div>
            <div v-text="(this?.prop2)?.shift?.()"></div>
            <div v-text="(this?.prop3?.shift)?.()"></div>
          </div>
        </template>
        <script>
          export default {
            props: ['prop1', 'prop2', 'prop3']
          }
        </script>
      `,
      errors: [
        'Unexpected mutation of "prop1" prop.',
        'Unexpected mutation of "prop2" prop.',
        'Unexpected mutation of "prop3" prop.'
      ]
    },
    {
      filename: 'test.vue',
      code: `
        <template>
          <div>
            <input v-model="prop1.text">
            <input v-model="prop2">
            <input v-model="this.prop3.text">
            <input v-model="this.prop4">
          </div>
        </template>
        <script>
          export default {
            props: ['prop1', 'prop2', 'prop3', 'prop4']
          }
        </script>
      `,
      errors: [
        {
          message: 'Unexpected mutation of "prop1" prop.',
          line: 4
        },
        {
          message: 'Unexpected mutation of "prop2" prop.',
          line: 5
        },
        {
          message: 'Unexpected mutation of "prop3" prop.',
          line: 6
        },
        {
          message: 'Unexpected mutation of "prop4" prop.',
          line: 7
        }
      ]
    },
    {
      filename: 'test.vue',
      code: `
        <script>
          export default {
            props: {
              todo: {
                type: Object,
                required: true
              },
              items: {
                type: Array,
                default: []
              }
            },
            methods: {
              openModal() {
                ++this.items
                this.todo.type = 'completed'
                this.items.push('something')
              }
            }
          }
        </script>
      `,
      errors: [
        {
          message: 'Unexpected mutation of "items" prop.',
          line: 16
        },
        {
          message: 'Unexpected mutation of "todo" prop.',
          line: 17
        },
        {
          message: 'Unexpected mutation of "items" prop.',
          line: 18
        }
      ]
    },
    {
      filename: 'test.vue',
      code: `
        <script>
          export default {
            props: ['foo', 'bar', 'baz'],
            methods: {
              openModal() {
                this?.foo?.push?.('something')
                ;(this?.bar)?.push?.('something')
                ;(this?.baz?.push)?.('something')
              }
            }
          }
        </script>
      `,
      errors: [
        'Unexpected mutation of "foo" prop.',
        'Unexpected mutation of "bar" prop.',
        'Unexpected mutation of "baz" prop.'
      ]
    },
    {
      filename: 'test.vue',
      code: `
        <template>
          <div>
            <template v-for="(test, index) of data">
              <template v-for="(prop, index) of data">
                <input v-model="prop">
              </template>
              <input v-model="prop">
            </template>
          </div>
        </template>
        <script>
          export default {
            props: ['prop']
          }
        </script>
      `,
      errors: [
        {
          message: 'Unexpected mutation of "prop" prop.',
          line: 8
        }
      ]
    },
    {
      filename: 'test.vue',
      code: `
        <template>
          <div>
            <template v-for="prop of data">
              <input v-model="this.prop">
              <div v-text="prop.shift()"></div>
              <div v-text="this.prop.shift()"></div>
            </template>
          </div>
        </template>
        <script>
          export default {
            props: ['prop']
          }
        </script>
      `,
      errors: [
        {
          message: 'Unexpected mutation of "prop" prop.',
          line: 5
        },
        {
          message: 'Unexpected mutation of "prop" prop.',
          line: 7
        }
      ]
    },

    // setup
    {
      filename: 'test.vue',
      code: `
        <script>
          export default {
            setup(props) {
              props.a ++
              props.b = 1
              props.c.push(1)
            }
          }
        </script>
      `,
      errors: [
        {
          message: 'Unexpected mutation of "a" prop.',
          line: 5
        },
        {
          message: 'Unexpected mutation of "b" prop.',
          line: 6
        },
        {
          message: 'Unexpected mutation of "c" prop.',
          line: 7
        }
      ]
    },
    {
      filename: 'test.vue',
      code: `
        <script>
          export default {
            setup({a,b,c, d: [e, , f]}) {
              a.foo ++
              b.foo = 1
              c.push(1)

              c.x.push(1)
              e.foo++
              f.foo++
            }
          }
        </script>
      `,
      errors: [
        {
          message: 'Unexpected mutation of "a" prop.',
          line: 5
        },
        {
          message: 'Unexpected mutation of "b" prop.',
          line: 6
        },
        {
          message: 'Unexpected mutation of "c" prop.',
          line: 7
        },
        {
          message: 'Unexpected mutation of "c" prop.',
          line: 9
        },
        {
          message: 'Unexpected mutation of "d" prop.',
          line: 10
        },
        {
          message: 'Unexpected mutation of "d" prop.',
          line: 11
        }
      ]
    },

    {
      filename: 'test.vue',
      code: `
        <script>
          export default {
            setup({a: foo, b: [...bar], c: baz = 1}) {
              foo.x ++
              bar.x = 1
              baz.push(1)
            }
          }
        </script>
      `,
      errors: [
        {
          message: 'Unexpected mutation of "a" prop.',
          line: 5
        },
        {
          message: 'Unexpected mutation of "b" prop.',
          line: 6
        },
        {
          message: 'Unexpected mutation of "c" prop.',
          line: 7
        }
      ]
    },
    {
      filename: 'test.vue',
      code: `
        <script>
          export default {
            setup({...props}) {
              props.a ++
              props.b = 1
              props.c.push(1)
            }
          }
        </script>
      `,
      errors: [
        {
          message: 'Unexpected mutation of "a" prop.',
          line: 5
        },
        {
          message: 'Unexpected mutation of "b" prop.',
          line: 6
        },
        {
          message: 'Unexpected mutation of "c" prop.',
          line: 7
        }
      ]
    },
    {
      filename: 'test.vue',
      code: `
        <script>
          export default {
            setup(props) {
              props[a] ++
            }
          }
        </script>
      `,
      errors: ['Unexpected mutation of "[a]" prop.']
    },
    {
      filename: 'test.vue',
      code: `
        <script>
          export default {
            setup({[a]: c}) {
              c.foo ++
            }
          }
        </script>
      `,
      errors: ['Unexpected mutation of "[a]" prop.']
    },

    {
      filename: 'test.vue',
      code: `
        <template>
          <input v-model="value">
          <input v-model="props.value">
        </template>
        <script setup>
        const props = defineProps({
          value: String,
        })
        </script>
      `,
      errors: [
        {
          message: 'Unexpected mutation of "value" prop.',
          line: 3
        },
        {
          message: 'Unexpected mutation of "props" prop.',
          line: 4
        }
      ]
    },
    {
      filename: 'test.vue',
      code: `
        <script setup>
        const props = defineProps({
          value: String,
        })
        props.value++
        </script>
      `,
      errors: [
        {
          message: 'Unexpected mutation of "value" prop.',
          line: 6
        }
      ]
    },
    {
      filename: 'test.vue',
      code: `
        <script setup>
        const {value} = defineProps({
          value: Object,
        })
        value.value++
        </script>
      `,
      errors: [
        {
          message: 'Unexpected mutation of "value" prop.',
          line: 6
        }
      ]
    },
    {
      filename: 'test.vue',
      code: `
        <script setup lang="ts">
        const props = withDefaults(defineProps<Props>(), {
          msg: 'hello'
        })
        props.value++
        </script>
      `,
      parserOptions: {
        parser: require.resolve('@typescript-eslint/parser')
      },
      errors: [
        {
          message: 'Unexpected mutation of "value" prop.',
          line: 6
        }
      ]
    }
  ]
})