vize:croquis/cf/spread-breaks-reactivity

Spreading a reactive object copies its values and drops the tracking.

Default severity: error
Applies to: Analyzed component graph and the supported facts described below
Automatic fix: None; review related files and apply the repair
Options: No per-code options; supported CLI findings accept severity overrides

import { defineConfig } from "@vizejs/vite-plugin/vite-plus";

export default defineConfig({
  lint: {
    vize: { preset: "incremental", crossFile: true,
      rules: { "croquis/cf/spread-breaks-reactivity": "warn" },
    },
  },
});

vp run lint

Shared project files

Use these unchanged files in both Bad and Good. Install the imported packages in the project: Vue, plus vue-router or Pinia where shown. Follow any version-specific support note. The entry root makes the component relationship explicit.

main.ts

import { createApp } from "vue";
import Root from "./UserPage.vue";
createApp(Root).mount("#app");

index.html

<div id="app"></div>
<script type="module" src="/main.ts"></script>

Bad

UserSummary.vue spreads props.user into a new object, taking a snapshot of the incoming reactive data.

UserPage.vue

<script setup lang="ts">
import { reactive } from "vue";
import UserSummary from "./UserSummary.vue";

const user = reactive({ name: "Ada", role: "admin" });
</script>

<template>
  <UserSummary :user="user" />
</template>

UserSummary.vue

<script setup lang="ts">
const props = defineProps<{ user: { name: string; role: string } }>();
const copiedUser = { ...props.user };
</script>

Good

toRef(props, "user") keeps a reference to the incoming prop instead of copying its fields.

UserPage.vue

<script setup lang="ts">
import { reactive } from "vue";
import UserSummary from "./UserSummary.vue";

const user = reactive({ name: "Ada", role: "admin" });
</script>

<template>
  <UserSummary :user="user" />
</template>

UserSummary.vue

<script setup lang="ts">
import { toRef } from "vue";

const props = defineProps<{ user: { name: string; role: string } }>();
const user = toRef(props, "user");
</script>

The Good files demonstrate the change described above; other diagnostics can still apply to the complete project.

Public explanation

Producer

Cross-file index