vue-best-practices — Практичные рекомендации для разработки на Vue

--- name: vue-best-practices description: MUST be used for Vue.js tasks. Strongly recommends Composition API with `<script setup>` and TypeScript as the standard approach. Covers Vue 3, SSR, Volar, vue-tsc. Load for any Vue, .vue files, Vue Router, Pinia, or Vite with Vue work. ALWAYS use Composition API unless the project explicitly requires Options API. license: MIT metadata: author: github.com/vuejs-ai version: "18.0.0" --- # Vue Best Practices Workflow Use this skill as an instruction set. Follow the workflow in order unless the user explicitly asks for a different order. ## Core Principles - **Keep state predictable:** one source of truth, derive everything else. - **Make data flow explicit:** Props down, Events up for most cases. - **Favor small, focused components:** easier to test, reuse, and maintain. - **Avoid unnecessary re-renders:** use computed properties and watchers wisely. - **Readability counts:** write clear, self-documenting code. ## 1) Confirm architecture before coding (required) - Default stack: Vue 3 + Composition API + `<script setup lang="ts">`. - If the project explicitly uses Options API, load `vue-options-api-best-practices` skill if available. - If the project explicitly uses JSX, load `vue-jsx-best-practices` skill if available. ### 1.1 Must-read core references (required) - Before implementing any Vue task, make sure to read and apply these core references: - `references/reactivity.md` - `references/sfc.md` - `references/component-data-flow.md` - `references/composables.md` - Keep these references in active working context for the entire task, not only when a specific issue appears. ### 1.2 Plan component boundaries before coding (required) Create a brief component map before implementation for any non-trivial feature. - Define each component's single responsibility in one sentence. - Keep entry/root and route-level view components as composition surfaces by default. - Move feature UI and feature logic out of entry/root/view components unless the task is intentionally a tiny single-file demo. - Define props/emits contracts for each child component in the map. - Prefer a feature folder layout (`components/<feature>/...`, `composables/use<Feature>.ts`) when adding more than one component. ## 2) Apply essential Vue foundations (required) These are essential, must-know foundations. Apply all of them in every Vue task using the core references already loaded in section `1.1`. ### Reactivity - Must-read reference from `1.1`: [reactivity](references/reactivity.md) - Keep source state minimal (`ref`/`reactive`), derive everything possible with `computed`. - Use watchers for side effects if needed. - Avoid recomputing expensive logic in templates. ### SFC structure and template safety - Must-read reference from `1.1`: [sfc](references/sfc.md) - Keep SFC sections in this order: `<script>` → `<template>` → `<style>`. - Keep SFC responsibilities focused; split large components. - Keep templates declarative; move branching/derivation to script. - Apply Vue template safety rules (`v-html`, list rendering, conditional rendering choices). ### Keep components focused Split a component when it has **more than one clear responsibility** (e.g. data orchestration + UI, or multiple independent UI sections). - Prefer **smaller components + composables** over one “mega component” - Move **UI sections** into child components (props in, events out). - Move **state/side effects** into composables (`useXxx()`). Apply objective split triggers. Split the component if **any** condition is true: - It owns both orchestration/state and substantial presentational markup for multiple sections. - It has 3+ distinct UI sections (for example: form, filters, list, footer/status). - A template block is repeated or could become reusable (item rows, cards, list entries). Entry/root and route view rule: - Keep entry/root and route view components thin: app shell/layout, provider wiring, and feature composition. - Do not place full feature implementations in entry/root/view components when those features contain independent parts. - For CRUD/list features (todo, table, catalog, inbox), split at least into: - feature container component - input/form component - list (and/or item) component - footer/actions or filter/status component - Allow a single-file implementation only for very small throwaway demos; if chosen, explicitly justify why splitting is unnecessary. ### Component data flow - Must-read reference from `1.1`: [component-data-flow](references/component-data-flow.md) - Use props down, events up as the primary model. - Use `v-model` only for true two-way component contracts. - Use provide/inject only for deep-tree dependencies or shared context. - Keep contracts explicit and typed with `defineProps`, `defineEmits`, and `InjectionKey` as needed. ### Composables - Must-read reference from `1.1`: [composables](references/composables.md) - Extract logic into composables when it is reused, stateful, or side-effect heavy. - Keep composable APIs small, typed, and predictable. - Separate feature logic from presentational components. ## 3) Consider optional features only when requirements call for them ### 3.1 Standard optional features Do not add these by default. Load the matching reference only when the requirement exists. - Slots: parent needs to control child content/layout -> [component-slots](references/component-slots.md) - Fallthrough attributes: wrapper/base components must forward attrs/events safely -> [component-fallthrough-attrs](references/component-fallthrough-attrs.md) - Built-in component `<KeepAlive>` for stateful view caching -> [component-keep-alive](references/component-keep-alive.md) - Built-in component `<Teleport>` for overlays/portals -> [component-teleport](references/component-teleport.md) - Built-in component `<Suspense>` for async subtree fallback boundaries -> [component-suspense](references/component-suspense.md) - Animation-related features: pick the simplest approach that matches the required motion behavior. - Built-in component `<Transition>` for enter/leave effects -> [transition](references/component-transition.md) - Built-in component `<TransitionGroup>` for animated list mutations -> [transition-group](references/component-transition-group.md) - Class-based animation for non-enter/leave effects -> [animation-class-based-technique](references/animation-class-based-technique.md) - State-driven animation for user-input-driven animation -> [animation-state-driven-technique](references/animation-state-driven-technique.md) ### 3.2 Less-common optional features Use these only when there is explicit product or technical need. - Directives: behavior is DOM-specific and not a good composable/component fit -> [directives](references/directives.md) - Async components: heavy/rarely-used UI should be lazy loaded -> [component-async](references/component-async.md) - Render functions only when templates cannot express the requirement -> [render-functions](references/render-functions.md) - Plugins when behavior must be installed app-wide -> [plugins](references/plugins.md) - State management patterns: app-wide shared state crosses feature boundaries -> [state-management](references/state-management.md) ## 4) Run performance optimization after behavior is correct Performance work is a post-functionality pass. Do not optimize before core behavior is implemented and verified. - Large list rendering bottlenecks -> [perf-virtualize-large-lists](references/perf-virtualize-large-lists.md) - Static subtrees re-rendering unnecessarily -> [perf-v-once-v-memo-directives](references/perf-v-once-v-memo-directives.md) - Over-abstraction in hot list paths -> [perf-avoid-component-abstraction-in-lists](references/perf-avoid-component-abstraction-in-lists.md) - Expensive updates triggered too often -> [updated-hook-performance](references/updated-hook-performance.md) ## 5) Final self-check before finishing - Core behavior works and matches requirements. - All must-read references were read and applied. - Reactivity model is minimal and predictable. - SFC structure and template rules are followed. - Components are focused and well-factored, splitting when needed. - Entry/root and route view components remain composition surfaces unless there is an explicit small-demo exception. - Component split decisions are explicit and defensible (responsibility boundaries are clear). - Data flow contracts are explicit and typed. - Composables are used where reuse/complexity justifies them. - Moved state/side effects into composables if applicable - Optional features are used only when requirements demand them. - Performance changes were applied only after functionality was complete.