fix: previous value undefined for nested fields in afterChange (#14582)

### What?
Updates the `previousValue` data sent to the `afterChange` hook to
accomodate nested paths.

### Why?
Currently the `afterChange` hook returns this:
```ts
previousValue: previousDoc?.[field.name],
```

For any nested fields, this breaks because it does not match the
structure of the incoming data.

### How?
Uses the path segments to correctly extract the relevant data.

**Reported by client.**

Author: jessrynkar

packages/payload/src/fields/hooks/afterChange/promise.ts

@@ -70,6 +70,8 @@ export const promise = async ({
   const pathSegments = path ? path.split('.') : []
   const schemaPathSegments = schemaPath ? schemaPath.split('.') : []
   const indexPathSegments = indexPath ? indexPath.split('-').filter(Boolean)?.map(Number) : []
+  const getNestedValue = (data: JsonObject, path: string[]) =>
+    path.reduce((acc, key) => (acc && acc[key] !== undefined ? acc[key] : undefined), data)
 
   if (fieldAffectsData(field)) {
     // Execute hooks
@@ -88,12 +90,12 @@ export const promise = async ({
           path: pathSegments,
           previousDoc,
           previousSiblingDoc,
-          previousValue: previousDoc?.[field.name],
+          previousValue: getNestedValue(previousDoc, pathSegments) ?? previousDoc?.[field.name],
           req,
           schemaPath: schemaPathSegments,
           siblingData,
           siblingFields: siblingFields!,
-          value: siblingDoc?.[field.name],
+          value: getNestedValue(siblingDoc, pathSegments) ?? siblingDoc?.[field.name],
         })
 
         if (hookedValue !== undefined) {

test/hooks/collections/NestedAfterChangeHook/index.ts

@@ -0,0 +1,40 @@
+import type { CollectionConfig } from 'payload'
+export const nestedAfterChangeHooksSlug = 'nested-after-change-hooks'
+
+const NestedAfterChangeHooks: CollectionConfig = {
+  slug: nestedAfterChangeHooksSlug,
+  fields: [
+    {
+      type: 'text',
+      name: 'text',
+    },
+    {
+      type: 'group',
+      name: 'group',
+      fields: [
+        {
+          type: 'array',
+          name: 'array',
+          fields: [
+            {
+              type: 'text',
+              name: 'nestedAfterChange',
+              hooks: {
+                afterChange: [
+                  ({ previousValue, operation }) => {
+                    console.log(previousValue)
+                    if (operation === 'update' && typeof previousValue === 'undefined') {
+                      throw new Error('previousValue is missing in nested beforeChange hook')
+                    }
+                  },
+                ],
+              },
+            },
+          ],
+        },
+      ],
+    },
+  ],
+}
+
+export default NestedAfterChangeHooks

test/hooks/config.ts

@@ -15,6 +15,7 @@ import ContextHooks from './collections/ContextHooks/index.js'
 import { DataHooks } from './collections/Data/index.js'
 import { FieldPaths } from './collections/FieldPaths/index.js'
 import Hooks, { hooksSlug } from './collections/Hook/index.js'
+import NestedAfterChangeHooks from './collections/NestedAfterChangeHook/index.js'
 import NestedAfterReadHooks from './collections/NestedAfterReadHooks/index.js'
 import Relations from './collections/Relations/index.js'
 import TransformHooks from './collections/Transform/index.js'
@@ -36,6 +37,7 @@ export const HooksConfig: Promise<SanitizedConfig> = buildConfigWithDefaults({
     TransformHooks,
     Hooks,
     NestedAfterReadHooks,
+    NestedAfterChangeHooks,
     ChainingHooks,
     Relations,
     Users,

test/hooks/int.spec.ts

@@ -14,6 +14,7 @@ import { chainingHooksSlug } from './collections/ChainingHooks/index.js'
 import { contextHooksSlug } from './collections/ContextHooks/index.js'
 import { dataHooksSlug } from './collections/Data/index.js'
 import { hooksSlug } from './collections/Hook/index.js'
+import { nestedAfterChangeHooksSlug } from './collections/NestedAfterChangeHook/index.js'
 import {
   generatedAfterReadText,
   nestedAfterReadHooksSlug,
@@ -328,6 +329,40 @@ describe('Hooks', () => {
 
       expect(retrievedDoc.value).toEqual('data from REST API')
     })
+
+    it('should populate previousValue in nested afterChange hooks', async () => {
+      // this collection will throw an error if previousValue is not defined in nested afterChange hook
+      const nestedAfterChangeDoc = await payload.create({
+        collection: nestedAfterChangeHooksSlug,
+        data: {
+          text: 'initial',
+          group: {
+            array: [
+              {
+                nestedAfterChange: 'initial',
+              },
+            ],
+          },
+        },
+      })
+
+      const updatedDoc = await payload.update({
+        collection: 'nested-after-change-hooks',
+        id: nestedAfterChangeDoc.id,
+        data: {
+          text: 'updated',
+          group: {
+            array: [
+              {
+                nestedAfterChange: 'updated',
+              },
+            ],
+          },
+        },
+      })
+
+      expect(updatedDoc).toBeDefined()
+    })
   })
 
   describe('auth collection hooks', () => {

test/hooks/payload-types.ts

@@ -74,12 +74,14 @@ export interface Config {
     transforms: Transform;
     hooks: Hook;
     'nested-after-read-hooks': NestedAfterReadHook;
+    'nested-after-change-hooks': NestedAfterChangeHook;
     'chaining-hooks': ChainingHook;
     relations: Relation;
     'hooks-users': HooksUser;
     'data-hooks': DataHook;
     'field-paths': FieldPath;
     'value-hooks': ValueHook;
+    'payload-kv': PayloadKv;
     'payload-locked-documents': PayloadLockedDocument;
     'payload-preferences': PayloadPreference;
     'payload-migrations': PayloadMigration;
@@ -93,12 +95,14 @@ export interface Config {
     transforms: TransformsSelect<false> | TransformsSelect<true>;
     hooks: HooksSelect<false> | HooksSelect<true>;
     'nested-after-read-hooks': NestedAfterReadHooksSelect<false> | NestedAfterReadHooksSelect<true>;
+    'nested-after-change-hooks': NestedAfterChangeHooksSelect<false> | NestedAfterChangeHooksSelect<true>;
     'chaining-hooks': ChainingHooksSelect<false> | ChainingHooksSelect<true>;
     relations: RelationsSelect<false> | RelationsSelect<true>;
     'hooks-users': HooksUsersSelect<false> | HooksUsersSelect<true>;
     'data-hooks': DataHooksSelect<false> | DataHooksSelect<true>;
     'field-paths': FieldPathsSelect<false> | FieldPathsSelect<true>;
     'value-hooks': ValueHooksSelect<false> | ValueHooksSelect<true>;
+    'payload-kv': PayloadKvSelect<false> | PayloadKvSelect<true>;
     'payload-locked-documents': PayloadLockedDocumentsSelect<false> | PayloadLockedDocumentsSelect<true>;
     'payload-preferences': PayloadPreferencesSelect<false> | PayloadPreferencesSelect<true>;
     'payload-migrations': PayloadMigrationsSelect<false> | PayloadMigrationsSelect<true>;
@@ -251,6 +255,24 @@ export interface Relation {
   updatedAt: string;
   createdAt: string;
 }
+/**
+ * This interface was referenced by `Config`'s JSON-Schema
+ * via the `definition` "nested-after-change-hooks".
+ */
+export interface NestedAfterChangeHook {
+  id: string;
+  text?: string | null;
+  group?: {
+    array?:
+      | {
+          nestedAfterChange?: string | null;
+          id?: string | null;
+        }[]
+      | null;
+  };
+  updatedAt: string;
+  createdAt: string;
+}
 /**
  * This interface was referenced by `Config`'s JSON-Schema
  * via the `definition` "chaining-hooks".
@@ -278,6 +300,13 @@ export interface HooksUser {
   hash?: string | null;
   loginAttempts?: number | null;
   lockUntil?: string | null;
+  sessions?:
+    | {
+        id: string;
+        createdAt?: string | null;
+        expiresAt: string;
+      }[]
+    | null;
   password?: string | null;
 }
 /**
@@ -625,6 +654,23 @@ export interface ValueHook {
   updatedAt: string;
   createdAt: string;
 }
+/**
+ * This interface was referenced by `Config`'s JSON-Schema
+ * via the `definition` "payload-kv".
+ */
+export interface PayloadKv {
+  id: string;
+  key: string;
+  data:
+    | {
+        [k: string]: unknown;
+      }
+    | unknown[]
+    | string
+    | number
+    | boolean
+    | null;
+}
 /**
  * This interface was referenced by `Config`'s JSON-Schema
  * via the `definition` "payload-locked-documents".
@@ -660,6 +706,10 @@ export interface PayloadLockedDocument {
         relationTo: 'nested-after-read-hooks';
         value: string | NestedAfterReadHook;
       } | null)
+    | ({
+        relationTo: 'nested-after-change-hooks';
+        value: string | NestedAfterChangeHook;
+      } | null)
     | ({
         relationTo: 'chaining-hooks';
         value: string | ChainingHook;
@@ -817,6 +867,25 @@ export interface NestedAfterReadHooksSelect<T extends boolean = true> {
   updatedAt?: T;
   createdAt?: T;
 }
+/**
+ * This interface was referenced by `Config`'s JSON-Schema
+ * via the `definition` "nested-after-change-hooks_select".
+ */
+export interface NestedAfterChangeHooksSelect<T extends boolean = true> {
+  text?: T;
+  group?:
+    | T
+    | {
+        array?:
+          | T
+          | {
+              nestedAfterChange?: T;
+              id?: T;
+            };
+      };
+  updatedAt?: T;
+  createdAt?: T;
+}
 /**
  * This interface was referenced by `Config`'s JSON-Schema
  * via the `definition` "chaining-hooks_select".
@@ -851,6 +920,13 @@ export interface HooksUsersSelect<T extends boolean = true> {
   hash?: T;
   loginAttempts?: T;
   lockUntil?: T;
+  sessions?:
+    | T
+    | {
+        id?: T;
+        createdAt?: T;
+        expiresAt?: T;
+      };
 }
 /**
  * This interface was referenced by `Config`'s JSON-Schema
@@ -940,6 +1016,14 @@ export interface ValueHooksSelect<T extends boolean = true> {
   updatedAt?: T;
   createdAt?: T;
 }
+/**
+ * This interface was referenced by `Config`'s JSON-Schema
+ * via the `definition` "payload-kv_select".
+ */
+export interface PayloadKvSelect<T extends boolean = true> {
+  key?: T;
+  data?: T;
+}
 /**
  * This interface was referenced by `Config`'s JSON-Schema
  * via the `definition` "payload-locked-documents_select".