Add parent context with name and prop values to the callback context of route props

src/services/createPropStore.ts

@@ -7,6 +7,7 @@ import { CallbackPushResponse, CallbackRejectResponse, CallbackSuccessResponse,
 import { CallbackContextPushError } from '@/errors/callbackContextPushError'
 import { CallbackContextRejectionError } from '@/errors/callbackContextRejectionError'
 import { getPropsValue } from '@/utilities/props'
+import { PropsCallbackParent } from '@/types/props'
 
 export const propStoreKey: InjectionKey<PropStore> = Symbol()
 
@@ -39,6 +40,7 @@ export function createPropStore(): PropStore {
           push,
           replace,
           reject,
+          parent: getParentContext(route, true),
         }))
 
         response[key] = value
@@ -72,6 +74,7 @@ export function createPropStore(): PropStore {
           push,
           replace,
           reject,
+          parent: getParentContext(route),
         }))
 
         store.set(key, value)
@@ -111,6 +114,59 @@ export function createPropStore(): PropStore {
     return store.get(key)
   }
 
+  function getParentContext(route: ResolvedRoute, prefetch: boolean = false): PropsCallbackParent {
+    const parent = route.matches.at(-2)
+
+    if (!parent) {
+      return
+    }
+
+    if (isWithComponentProps(parent)) {
+      return {
+        name: parent.name ?? '',
+        get props() {
+          return getParentProps(parent, 'default', route, prefetch)
+        },
+      }
+    }
+
+    if (isWithComponentPropsRecord(parent)) {
+      return {
+        name: parent.name ?? '',
+        props: new Proxy({}, {
+          get(target, name) {
+            if (typeof name !== 'string') {
+              return Reflect.get(target, name)
+            }
+
+            return getParentProps(parent, name, route, prefetch)
+          },
+        }),
+      }
+    }
+
+    return {
+      name: parent.name ?? '',
+      props: undefined,
+    }
+  }
+
+  function getParentProps(parent: Route['matched'], name: string, route: ResolvedRoute, prefetch: boolean = false): unknown {
+    const value = getProps(parent.id, name, route)
+
+    if (prefetch && !value) {
+      const parentName = parent.name ?? 'unknown'
+      const routeName = route.name || 'unknown'
+
+      console.warn(`
+        Unable to access parent props "${name}" from route "${parentName}" while prefetching props for route "${routeName}".
+        This may occur if the parent route's props were not also prefetched.
+      `)
+    }
+
+    return value
+  }
+
   function getPropKey(id: string, name: string, route: ResolvedRoute): string {
     return [id, name, route.id, JSON.stringify(route.params)].join('-')
   }

src/services/createRoute.spec-d.ts

@@ -406,3 +406,105 @@ test('undefined is not a valid value for 2nd argument of createRoute', () => {
 
   expectTypeOf<Source>().toEqualTypeOf<Expect>()
 })
+
+test('parent props are undefined when parent has no props', () => {
+  const parent = createRoute({
+    name: 'parent',
+  })
+
+  createRoute({
+    name: 'child',
+    parent: parent,
+  }, (__, { parent }) => {
+    expectTypeOf(parent.props).toEqualTypeOf<undefined>()
+    expectTypeOf(parent.name).toEqualTypeOf<'parent'>()
+
+    return {}
+  })
+})
+
+test('sync parent props are passed to child props', () => {
+  const parent = createRoute({
+    name: 'parent',
+  }, () => ({ foo: 123 }))
+
+  createRoute({
+    name: 'child',
+    parent: parent,
+  }, (__, { parent }) => {
+    expectTypeOf(parent.props).toEqualTypeOf<{ foo: number }>()
+    expectTypeOf(parent.name).toEqualTypeOf<'parent'>()
+
+    return {}
+  })
+})
+
+test('async parent props are passed to child props', () => {
+  const parent = createRoute({
+    name: 'parent',
+  }, async () => ({ foo: 123 }))
+
+  createRoute({
+    name: 'child',
+    parent: parent,
+  }, (__, { parent }) => {
+    expectTypeOf(parent.props).toEqualTypeOf<Promise<{ foo: number }>>()
+    expectTypeOf(parent.name).toEqualTypeOf<'parent'>()
+
+    return {}
+  })
+})
+
+test('parent props are passed to child props when multiple parent components are used', () => {
+  const parent = createRoute({
+    name: 'parent',
+    components: {
+      one: component,
+      two: component,
+    },
+  }, {
+    one: () => ({ foo: 123 }),
+    two: async () => ({ foo: 456 }),
+  })
+
+  createRoute({
+    name: 'child',
+    parent: parent,
+  }, (__, { parent }) => {
+    expectTypeOf(parent.props).toEqualTypeOf<{
+      one: { foo: number },
+      two: Promise<{ foo: number }>,
+    }>()
+    expectTypeOf(parent.name).toEqualTypeOf<'parent'>()
+
+    return {}
+  })
+})
+
+test('parent props are passed to child props when multiple child components are used', () => {
+  const parent = createRoute({
+    name: 'parent',
+  }, async () => ({ foo: 123 }))
+
+  createRoute({
+    name: 'child',
+    parent: parent,
+    components: {
+      one: component,
+      two: component,
+    },
+  }, {
+    one: (__, { parent }) => {
+      expectTypeOf(parent.props).toEqualTypeOf<Promise<{ foo: number }>>()
+      expectTypeOf(parent.name).toEqualTypeOf<'parent'>()
+
+      return {}
+    },
+    two: (__, { parent }) => {
+      expectTypeOf(parent.props).toEqualTypeOf<Promise<{ foo: number }>>()
+      expectTypeOf(parent.name).toEqualTypeOf<'parent'>()
+
+      return {}
+    },
+  })
+})

src/services/createRoute.spec.ts

@@ -1,7 +1,9 @@
-import { expect, test } from 'vitest'
+import { expect, test, vi } from 'vitest'
 import { createRoute } from '@/services/createRoute'
 import { path } from '@/services/path'
 import { query } from '@/services/query'
+import { createRouter } from '@/main'
+import { component } from '@/utilities/testHelpers'
 
 test('given parent, path is combined', () => {
   const parent = createRoute({
@@ -110,3 +112,156 @@ test('given parent and child without meta, meta matches parent', () => {
     foo: 123,
   })
 })
+
+test('parent context is passed to child props', async () => {
+  const spy = vi.fn()
+  const parent = createRoute({
+    name: 'parent',
+  })
+
+  const child = createRoute({
+    name: 'child',
+    parent: parent,
+    path: '/child',
+  }, (_, { parent }) => {
+    return spy(parent)
+  })
+
+  const router = createRouter([parent, child], {
+    initialUrl: '/child',
+  })
+
+  await router.start()
+
+  expect(spy).toHaveBeenCalledWith({ name: 'parent', props: undefined })
+})
+
+test('sync parent props are passed to child props', async () => {
+  const spy = vi.fn()
+
+  const parent = createRoute({
+    name: 'parent',
+  }, () => ({ foo: 123 }))
+
+  const child = createRoute({
+    name: 'child',
+    parent: parent,
+    path: '/child',
+  }, (__, { parent }) => {
+    return spy({ value: parent.props.foo })
+  })
+
+  const router = createRouter([parent, child], {
+    initialUrl: '/child',
+  })
+
+  await router.start()
+
+  expect(spy).toHaveBeenCalledWith({ value: 123 })
+})
+
+test('async parent props are passed to child props', async () => {
+  const spy = vi.fn()
+
+  const parent = createRoute({
+    name: 'parent',
+  }, async () => ({ foo: 123 }))
+
+  const child = createRoute({
+    name: 'child',
+    parent: parent,
+    path: '/child',
+  }, async (__, { parent }) => {
+    expect(parent.props).toBeDefined()
+    expect(parent.props).toBeInstanceOf(Promise)
+
+    const { foo: value } = await parent.props
+
+    return spy({ value })
+  })
+
+  const router = createRouter([parent, child], {
+    initialUrl: '/child',
+  })
+
+  await router.start()
+
+  expect(spy).toHaveBeenCalledWith({ value: 123 })
+})
+
+test('sync parent props with multiple views are passed to child props', async () => {
+  const spy = vi.fn()
+
+  const parent = createRoute({
+    name: 'parent',
+    components: {
+      one: component,
+      two: component,
+      three: component,
+    },
+  }, {
+    one: () => ({ foo: 123 }),
+    two: () => ({ bar: 456 }),
+  })
+
+  const child = createRoute({
+    name: 'child',
+    parent: parent,
+    path: '/child',
+  }, (__, { parent }) => {
+    return spy({
+      value1: parent.props.one.foo,
+      value2: parent.props.two.bar,
+    })
+  })
+
+  const router = createRouter([parent, child], {
+    initialUrl: '/child',
+  })
+
+  await router.start()
+
+  expect(spy).toHaveBeenCalledWith({ value1: 123, value2: 456 })
+})
+
+test('async parent props with multiple views are passed to child props', async () => {
+  const spy = vi.fn()
+
+  const parent = createRoute({
+    name: 'parent',
+    components: {
+      one: component,
+      two: component,
+      three: component,
+    },
+  }, {
+    one: async () => ({ foo: 123 }),
+    two: async () => ({ bar: 456 }),
+  })
+
+  const child = createRoute({
+    name: 'child',
+    parent: parent,
+    path: '/child',
+  }, async (__, { parent }) => {
+    expect(parent.props).toBeDefined()
+    expect(parent.props.one).toBeInstanceOf(Promise)
+    expect(parent.props.two).toBeInstanceOf(Promise)
+
+    const { foo: value1 } = await parent.props.one
+    const { bar: value2 } = await parent.props.two
+
+    return spy({
+      value1,
+      value2,
+    })
+  })
+
+  const router = createRouter([parent, child], {
+    initialUrl: '/child',
+  })
+
+  await router.start()
+
+  expect(spy).toHaveBeenCalledWith({ value1: 123, value2: 456 })
+})

src/types/createRouteOptions.ts

@@ -129,7 +129,7 @@ export type CreateRouteOptions<
 export type PropsGetter<
   TOptions extends CreateRouteOptions = CreateRouteOptions,
   TComponent extends Component = Component
-> = (route: ResolvedRoute<ToRoute<TOptions, undefined>>, context: PropsCallbackContext) => MaybePromise<ComponentProps<TComponent>>
+> = (route: ResolvedRoute<ToRoute<TOptions, undefined>>, context: PropsCallbackContext<TOptions['parent']>) => MaybePromise<ComponentProps<TComponent>>
 
 type ComponentPropsAreOptional<
   TComponent extends Component