feat(plugin-redirects)!: update fields overrides to use a function (#6675)

## Description

Updates the `fields` override in plugin redirects to allow for
overriding

```ts
// before
overrides: {
  fields: [
    {
      type: 'text',
      name: 'customField',
    },
  ],
},

// current
overrides: {
  fields: ({ defaultFields }) => {
    return [
      ...defaultFields,
      {
        type: 'text',
        name: 'customField',
      },
    ]
  },
},
```


## Type of change

- [x] New feature (non-breaking change which adds functionality)
- [x] Breaking change (fix or feature that would cause existing
functionality to not work as expected)

packages/plugin-redirects/src/deepMerge.ts

@@ -1,34 +0,0 @@
-// @ts-nocheck
-
-/**
- * Simple object check.
- * @param item
- * @returns {boolean}
- */
-export function isObject(item: unknown): boolean {
-  return item && typeof item === 'object' && !Array.isArray(item)
-}
-
-/**
- * Deep merge two objects.
- * @param target
- * @param ...sources
- */
-export default function deepMerge<T, R>(target: T, source: R): T {
-  const output = { ...target }
-  if (isObject(target) && isObject(source)) {
-    Object.keys(source).forEach((key) => {
-      if (isObject(source[key])) {
-        if (!(key in target)) {
-          Object.assign(output, { [key]: source[key] })
-        } else {
-          output[key] = deepMerge(target[key], source[key])
-        }
-      } else {
-        Object.assign(output, { [key]: source[key] })
-      }
-    })
-  }
-
-  return output
-}

packages/plugin-redirects/src/index.ts

@@ -1,25 +1,12 @@
 import type { Config } from 'payload/config'
+import type { CollectionConfig, Field } from 'payload/types'
 
 import type { RedirectsPluginConfig } from './types.js'
 
-import deepMerge from './deepMerge.js'
-
 export const redirectsPlugin =
   (pluginConfig: RedirectsPluginConfig) =>
-  (incomingConfig: Config): Config => ({
+  (incomingConfig: Config): Config => {
-    ...incomingConfig,
+    const defaultFields: Field[] = [
-    collections: [
-      ...(incomingConfig?.collections || []),
-      deepMerge(
-        {
-          slug: 'redirects',
-          access: {
-            read: (): boolean => true,
-          },
-          admin: {
-            defaultColumns: ['from', 'to.type', 'createdAt'],
-          },
-          fields: [
       {
         name: 'from',
         type: 'text',
@@ -72,9 +59,27 @@ export const redirectsPlugin =
         ],
         label: false,
       },
-          ],
+    ]
+
+    const redirectsCollection: CollectionConfig = {
+      ...(pluginConfig?.overrides || {}),
+      slug: pluginConfig?.overrides?.slug || 'redirects',
+      access: {
+        read: () => true,
+        ...(pluginConfig?.overrides?.access || {}),
       },
-        pluginConfig?.overrides || {},
+      admin: {
-      ),
+        defaultColumns: ['from', 'to.type', 'createdAt'],
-    ],
+        ...(pluginConfig?.overrides?.admin || {}),
-  })
+      },
+      fields:
+        pluginConfig?.overrides?.fields && typeof pluginConfig?.overrides?.fields === 'function'
+          ? pluginConfig?.overrides.fields({ defaultFields })
+          : defaultFields,
+    }
+
+    return {
+      ...incomingConfig,
+      collections: [...(incomingConfig?.collections || []), redirectsCollection],
+    }
+  }

packages/plugin-redirects/src/types.ts

@@ -1,6 +1,8 @@
-import type { CollectionConfig } from 'payload/types'
+import type { CollectionConfig, Field } from 'payload/types'
+
+export type FieldsOverride = (args: { defaultFields: Field[] }) => Field[]
 
 export type RedirectsPluginConfig = {
   collections?: string[]
-  overrides?: Partial<CollectionConfig>
+  overrides?: Partial<Omit<CollectionConfig, 'fields'>> & { fields: FieldsOverride }
 }

test/plugin-redirects/config.ts

@@ -27,6 +27,17 @@ export default buildConfigWithDefaults({
   plugins: [
     redirectsPlugin({
       collections: ['pages'],
+      overrides: {
+        fields: ({ defaultFields }) => {
+          return [
+            ...defaultFields,
+            {
+              type: 'text',
+              name: 'customField',
+            },
+          ]
+        },
+      },
     }),
   ],
 })