Support for merging nested prop paths

packages/core/src/response.ts

@@ -1,4 +1,5 @@
 import { AxiosResponse } from 'axios'
+import { get, set } from 'lodash-es'
 import { router } from '.'
 import { fireErrorEvent, fireInvalidEvent, firePrefetchedEvent, fireSuccessEvent } from './events'
 import { history } from './history'
@@ -221,50 +222,60 @@ export class Response {
       return
     }
 
-    const propsToMerge = pageResponse.mergeProps || []
+    const propsToAppend = pageResponse.mergeProps || []
+    const propsToPrepend = pageResponse.prependProps || []
     const propsToDeepMerge = pageResponse.deepMergeProps || []
     const matchPropsOn = pageResponse.matchPropsOn || []
 
-    propsToMerge.forEach((prop) => {
-      const incomingProp = pageResponse.props[prop]
+    const mergeProp = (prop: string, shouldAppend: boolean) => {
+      const currentProp = get(currentPage.get().props, prop)
+      const incomingProp = get(pageResponse.props, prop)
 
       if (Array.isArray(incomingProp)) {
-        pageResponse.props[prop] = this.mergeOrMatchItems(
-          (currentPage.get().props[prop] || []) as any[],
+        const newArray = this.mergeOrMatchItems(
+          (currentProp || []) as any[],
           incomingProp,
           prop,
           matchPropsOn,
+          shouldAppend,
         )
+
+        set(pageResponse.props, prop, newArray)
       } else if (typeof incomingProp === 'object' && incomingProp !== null) {
-        pageResponse.props[prop] = {
-          ...((currentPage.get().props[prop] || []) as Record<string, any>),
+        const newObject = {
+          ...(currentProp || {}),
           ...incomingProp,
         }
+
+        set(pageResponse.props, prop, newObject)
       }
-    })
+    }
+
+    propsToAppend.forEach((prop) => mergeProp(prop, true))
+    propsToPrepend.forEach((prop) => mergeProp(prop, false))
 
     propsToDeepMerge.forEach((prop) => {
-      const incomingProp = pageResponse.props[prop]
       const currentProp = currentPage.get().props[prop]
+      const incomingProp = pageResponse.props[prop]
 
       // Function to recursively merge objects and arrays
-      const deepMerge = (target: any, source: any, currentKey: string) => {
+      const deepMerge = (target: any, source: any, matchProp: string) => {
         if (Array.isArray(source)) {
-          return this.mergeOrMatchItems(target, source, currentKey, matchPropsOn)
+          return this.mergeOrMatchItems(target, source, matchProp, matchPropsOn)
         }
 
         if (typeof source === 'object' && source !== null) {
           // Merge objects by iterating over keys
           return Object.keys(source).reduce(
             (acc, key) => {
-              acc[key] = deepMerge(target ? target[key] : undefined, source[key], `${currentKey}.${key}`)
+              acc[key] = deepMerge(target ? target[key] : undefined, source[key], `${matchProp}.${key}`)
               return acc
             },
             { ...target },
           )
         }
 
-        // f the source is neither an array nor an object, simply return the it
+        // If the source is neither an array nor an object, simply return the it
         return source
       }
 
@@ -275,45 +286,94 @@ export class Response {
     pageResponse.props = { ...currentPage.get().props, ...pageResponse.props }
   }
 
-  protected mergeOrMatchItems(target: any[], source: any[], currentKey: string, matchPropsOn: string[]) {
-    // Determine if there's a specific key to match items.
-    // E.g.: matchPropsOn = ['posts.data.id'] and currentKey = 'posts.data' will match.
-    const matchOn = matchPropsOn.find((key) => {
-      const path = key.split('.').slice(0, -1).join('.')
-      return path === currentKey
+  protected mergeOrMatchItems(
+    existingItems: any[],
+    newItems: any[],
+    matchProp: string,
+    matchPropsOn: string[],
+    shouldAppend = true,
+  ) {
+    const items = Array.isArray(existingItems) ? existingItems : []
+
+    // Find the matching key for this specific property path
+    const matchingKey = matchPropsOn.find((key) => {
+      const keyPath = key.split('.').slice(0, -1).join('.')
+
+      return keyPath === matchProp
     })
 
-    if (!matchOn) {
-      // No key found to match on, just concatenate the arrays
-      return [...(Array.isArray(target) ? target : []), ...source]
+    // If no matching key is configured, simply concatenate the arrays
+    if (!matchingKey) {
+      return shouldAppend ? [...items, ...newItems] : [...newItems, ...items]
     }
 
-    // Extract the unique property name to match items (e.g., 'id' from 'posts.data.id').
-    const uniqueProperty = matchOn.split('.').pop() || ''
-    const targetArray = Array.isArray(target) ? target : []
-    const map = new Map<any, any>()
+    // Extract the property name we'll use to match items (e.g., 'id' from 'users.data.id')
+    const uniqueProperty = matchingKey.split('.').pop() || ''
 
-    // Populate the map with items from the target array, using the unique property as the key.
-    // If an item doesn't have the unique property or isn't an object, a unique Symbol is used as the key.
-    targetArray.forEach((item) => {
-      if (item && typeof item === 'object' && uniqueProperty in item) {
-        map.set(item[uniqueProperty], item)
-      } else {
-        map.set(Symbol(), item)
+    // Create a map of new items by their unique property lookups
+    const newItemsMap = new Map()
+
+    newItems.forEach((item) => {
+      if (this.hasUniqueProperty(item, uniqueProperty)) {
+        newItemsMap.set(item[uniqueProperty], item)
       }
     })
 
-    // Iterate through the source array. If an item's unique property matches an existing key in the map,
-    // update the item. Otherwise, add the new item to the map.
-    source.forEach((item) => {
-      if (item && typeof item === 'object' && uniqueProperty in item) {
-        map.set(item[uniqueProperty], item)
-      } else {
-        map.set(Symbol(), item)
+    return shouldAppend
+      ? this.appendWithMatching(items, newItems, newItemsMap, uniqueProperty)
+      : this.prependWithMatching(items, newItems, newItemsMap, uniqueProperty)
+  }
+
+  protected appendWithMatching(
+    existingItems: any[],
+    newItems: any[],
+    newItemsMap: Map<any, any>,
+    uniqueProperty: string,
+  ): any[] {
+    // Update existing items with new values, keep non-matching items
+    const updatedExisting = existingItems.map((item) => {
+      if (this.hasUniqueProperty(item, uniqueProperty) && newItemsMap.has(item[uniqueProperty])) {
+        return newItemsMap.get(item[uniqueProperty])
       }
+
+      return item
+    })
+
+    // Filter new items to only include those not already in existing items
+    const newItemsToAdd = newItems.filter((item) => {
+      if (!this.hasUniqueProperty(item, uniqueProperty)) {
+        return true // Always add items without unique property
+      }
+
+      return !existingItems.some(
+        (existing) =>
+          this.hasUniqueProperty(existing, uniqueProperty) && existing[uniqueProperty] === item[uniqueProperty],
+      )
+    })
+
+    return [...updatedExisting, ...newItemsToAdd]
+  }
+
+  protected prependWithMatching(
+    existingItems: any[],
+    newItems: any[],
+    newItemsMap: Map<any, any>,
+    uniqueProperty: string,
+  ): any[] {
+    // Filter existing items, keeping only those not being updated
+    const untouchedExisting = existingItems.filter((item) => {
+      if (this.hasUniqueProperty(item, uniqueProperty)) {
+        return !newItemsMap.has(item[uniqueProperty])
+      }
+
+      return true
     })
 
-    return Array.from(map.values())
+    return [...newItems, ...untouchedExisting]
+  }
+
+  protected hasUniqueProperty(item: any, property: string): boolean {
+    return item && typeof item === 'object' && property in item
   }
 
   protected async setRememberedState(pageResponse: Page): Promise<void> {

packages/core/src/types.ts

@@ -118,6 +118,7 @@ export interface Page<SharedProps extends PageProps = PageProps> {
   encryptHistory: boolean
   deferredProps?: Record<string, VisitOptions['only']>
   mergeProps?: string[]
+  prependProps?: string[]
   deepMergeProps?: string[]
   matchPropsOn?: string[]
 

packages/react/test-app/Pages/ComplexMergeSelective.tsx

@@ -0,0 +1,30 @@
+import { router } from '@inertiajs/react'
+
+export default ({
+  mixed,
+}: {
+  mixed: {
+    name: string
+    users: string[]
+    chat: { data: number[] }
+    post: { id: number; comments: { allowed: boolean; data: string[] } }
+  }
+}) => {
+  const reload = () => {
+    router.reload({
+      only: ['mixed'],
+    })
+  }
+
+  return (
+    <div>
+      <div>name is {mixed.name}</div>
+      <div>users: {mixed.users.join(', ')}</div>
+      <div>chat.data: {mixed.chat.data.join(', ')}</div>
+      <div>post.id: {mixed.post.id}</div>
+      <div>post.comments.allowed: {mixed.post.comments.allowed ? 'true' : 'false'}</div>
+      <div>post.comments.data: {mixed.post.comments.data.join(', ')}</div>
+      <button onClick={reload}>Reload</button>
+    </div>
+  )
+}

packages/react/test-app/Pages/MergeNestedProps.tsx

@@ -0,0 +1,24 @@
+import { router } from '@inertiajs/react'
+
+export default ({
+  users,
+}: {
+  users: { data: { id: number; name: string }[]; meta: { page: number; perPage: number } }
+}) => {
+  const loadMore = () => {
+    router.reload({
+      only: ['users'],
+      data: { page: users.meta.page + 1 },
+    })
+  }
+
+  return (
+    <div>
+      <p id="users">{users.data.map((user) => user.name).join(', ')}</p>
+      <p id="meta">
+        Page: {users.meta.page}, Per Page: {users.meta.perPage}
+      </p>
+      <button onClick={loadMore}>Load More</button>
+    </div>
+  )
+}

packages/svelte/test-app/Pages/ComplexMergeSelective.svelte

@@ -0,0 +1,24 @@
+<script lang="ts">
+  import { router } from '@inertiajs/svelte'
+
+  export let mixed: {
+    name: string
+    users: string[]
+    chat: { data: number[] }
+    post: { id: number; comments: { allowed: boolean; data: string[] } }
+  }
+
+  const reload = () => {
+    router.reload({
+      only: ['mixed'],
+    })
+  }
+</script>
+
+<div>name is {mixed.name}</div>
+<div>users: {mixed.users.join(', ')}</div>
+<div>chat.data: {mixed.chat.data.join(', ')}</div>
+<div>post.id: {mixed.post.id}</div>
+<div>post.comments.allowed: {mixed.post.comments.allowed ? 'true' : 'false'}</div>
+<div>post.comments.data: {mixed.post.comments.data.join(', ')}</div>
+<button on:click={reload}>Reload</button>

packages/svelte/test-app/Pages/MergeNestedProps.svelte

@@ -0,0 +1,21 @@
+<script lang="ts">
+  import { router } from '@inertiajs/svelte'
+
+  export let users: { data: { id: number; name: string }[]; meta: { page: number; perPage: number } } = {
+    data: [],
+    meta: { page: 1, perPage: 10 },
+  }
+
+  const loadMore = () => {
+    router.reload({
+      only: ['users'],
+      data: { page: users.meta.page + 1 },
+    })
+  }
+</script>
+
+<div>
+  <p id="users">{users.data.map((user) => user.name).join(', ')}</p>
+  <p id="meta">Page: {users.meta.page}, Per Page: {users.meta.perPage}</p>
+  <button on:click={loadMore}>Load More</button>
+</div>

packages/vue3/src/app.ts

@@ -135,6 +135,7 @@ export function usePage<SharedProps extends PageProps>(): Page<SharedProps> {
     clearHistory: computed(() => page.value?.clearHistory),
     deferredProps: computed(() => page.value?.deferredProps),
     mergeProps: computed(() => page.value?.mergeProps),
+    prependProps: computed(() => page.value?.prependProps),
     deepMergeProps: computed(() => page.value?.deepMergeProps),
     matchPropsOn: computed(() => page.value?.matchPropsOn),
     rememberedState: computed(() => page.value?.rememberedState),

packages/vue3/test-app/Pages/ComplexMergeSelective.vue

@@ -0,0 +1,30 @@
+<script setup lang="ts">
+import { router } from '@inertiajs/vue3'
+
+defineProps<{
+  mixed: {
+    name: string
+    users: string[]
+    chat: { data: number[] }
+    post: { id: number; comments: { allowed: boolean; data: string[] } }
+  }
+}>()
+
+const reload = () => {
+  router.reload({
+    only: ['mixed'],
+  })
+}
+</script>
+
+<template>
+  <div>
+    <div>name is {{ mixed.name }}</div>
+    <div>users: {{ mixed.users.join(', ') }}</div>
+    <div>chat.data: {{ mixed.chat.data.join(', ') }}</div>
+    <div>post.id: {{ mixed.post.id }}</div>
+    <div>post.comments.allowed: {{ mixed.post.comments.allowed ? 'true' : 'false' }}</div>
+    <div>post.comments.data: {{ mixed.post.comments.data.join(', ') }}</div>
+    <button @click="reload">Reload</button>
+  </div>
+</template>

packages/vue3/test-app/Pages/MergeNestedProps.vue

@@ -0,0 +1,22 @@
+<script setup lang="ts">
+import { router } from '@inertiajs/vue3'
+
+const props = defineProps<{
+  users: { data: { id: number; name: string }[]; meta: { page: number; perPage: number } }
+}>()
+
+const loadMore = () => {
+  router.reload({
+    only: ['users'],
+    data: { page: props.users.meta.page + 1 },
+  })
+}
+</script>
+
+<template>
+  <div>
+    <p id="users">{{ users.data.map((user) => user.name).join(', ') }}</p>
+    <p id="meta">Page: {{ users.meta.page }}, Per Page: {{ users.meta.perPage }}</p>
+    <button @click="loadMore">Load More</button>
+  </div>
+</template>