everything-claude-code/rules/vue/patterns.md

paths

paths
**/*.vue

Vue Patterns

This file extends common/patterns.md with Vue specific content.

Composables

• The composable (useXxx) is the reusable-logic unit. In Feature-Sliced Design it lives in the slice model segment.
• Accept MaybeRefOrGetter<T> inputs and normalize with toValue, so callers can pass a ref, a getter, or a raw value.
• Return toRefs(reactive(...)) so consumers can destructure without losing reactivity.
• A composable that uses lifecycle hooks or provide / inject must be called inside a component setup, not lazily or conditionally.

Props, Emits, v-model

• Type-based defineProps<Props>() and tuple-form defineEmits<{ change: [id: number] }>().
• defineModel<T>('name', { default }) for two-way binding. It compiles to a prop plus an update:* emit.

Provide / Inject

• Use provide / inject for tree-scoped data without prop drilling.
• Type-safe collision-free keys: const key = Symbol() as InjectionKey<T>.
• The provider owns mutations. Expose a readonly ref plus an explicit updater function, never a raw mutable ref.

Pinia (FSD model segment)

• Prefer setup stores: ref is state, computed is getters, function is actions.
• Setup stores do not get $reset for free. Define your own.
• Use storeToRefs for state and getters. Destructure actions directly off the store.
• Never persist raw auth tokens to localStorage.

vue-router

• Lazy-load route components with dynamic import().
• A global beforeEach auth gate keyed on meta.requiresAuth. Guards return false (cancel), a route location (redirect), or undefined / true (continue).
• Watch () => route.params.id, not the whole route object.

vue-query (server cache)

• @tanstack/vue-query owns server-cache state. Pinia owns client state.
• Put request functions plus queryOptions factories in the FSD api segment.
• Critical: put the ref or computed ITSELF in the query key, never .value. Passing .value freezes the key and kills reactive refetch.

useQuery({ queryKey: ['auction', id], queryFn: () => fetchAuction(toValue(id)) })
// after a mutation
queryClient.invalidateQueries({ queryKey: ['auction', id] })

Reference

• ECC skills: frontend-patterns, vite-patterns.
• Docs: https://pinia.vuejs.org/ · https://router.vuejs.org/ · https://tanstack.com/query/latest/docs/framework/vue/overview · https://vuejs.org/guide/reusability/composables.html