fix: disallow duplicate fieldNames to be used on the same level

packages/payload/src/errors/DuplicateFieldName.ts

@@ -0,0 +1,11 @@
+import APIError from './APIError'
+
+class DuplicateFieldName extends APIError {
+  constructor(fieldName: string) {
+    super(
+      `A field with the name '${fieldName}' was found multiple times on the same level. Field names must be unique.`,
+    )
+  }
+}
+
+export default DuplicateFieldName

packages/payload/src/errors/index.ts

@@ -2,6 +2,7 @@ export { default as errorHandler } from '../express/middleware/errorHandler'
 export { default as APIError } from './APIError'
 export { default as AuthenticationError } from './AuthenticationError'
 export { default as DuplicateCollection } from './DuplicateCollection'
+export { default as DuplicateFieldName } from './DuplicateFieldName'
 export { default as DuplicateGlobal } from './DuplicateGlobal'
 export { default as ErrorDeletingFile } from './ErrorDeletingFile'
 export { default as FileUploadError } from './FileUploadError'

packages/payload/src/fields/config/sanitize.ts

@@ -2,7 +2,12 @@ import type { Config } from '../../config/types'
 import type { Field } from './types'
 
 import withCondition from '../../admin/components/forms/withCondition'
-import { InvalidFieldName, InvalidFieldRelationship, MissingFieldType } from '../../errors'
+import {
+  DuplicateFieldName,
+  InvalidFieldName,
+  InvalidFieldRelationship,
+  MissingFieldType,
+} from '../../errors'
 import { formatLabels, toWords } from '../../utilities/formatLabels'
 import { baseBlockFields } from '../baseFields/baseBlockFields'
 import { baseIDField } from '../baseFields/baseIDField'
@@ -11,6 +16,7 @@ import { fieldAffectsData, tabHasName } from './types'
 
 type Args = {
   config: Config
+  existingFieldNames?: Set<string>
   fields: Field[]
   /**
    * If not null, will validate that upload and relationship fields do not relate to a collection that is not in this array.
@@ -19,7 +25,12 @@ type Args = {
   validRelationships: null | string[]
 }
 
-export const sanitizeFields = ({ config, fields, validRelationships }: Args): Field[] => {
+export const sanitizeFields = ({
+  config,
+  existingFieldNames = new Set(),
+  fields,
+  validRelationships,
+}: Args): Field[] => {
   if (!fields) return []
 
   return fields.map((unsanitizedField) => {
@@ -100,6 +111,12 @@ export const sanitizeFields = ({ config, fields, validRelationships }: Args): Fi
     }
 
     if (fieldAffectsData(field)) {
+      if (existingFieldNames.has(field.name)) {
+        throw new DuplicateFieldName(field.name)
+      } else if (!['id', 'blockName'].includes(field.name)) {
+        existingFieldNames.add(field.name)
+      }
+
       if (field.localized && !config.localization) delete field.localized
 
       if (typeof field.validate === 'undefined') {
@@ -126,6 +143,7 @@ export const sanitizeFields = ({ config, fields, validRelationships }: Args): Fi
     if ('fields' in field && field.fields) {
       field.fields = sanitizeFields({
         config,
+        existingFieldNames: fieldAffectsData(field) ? new Set() : existingFieldNames,
         fields: field.fields,
         validRelationships,
       })
@@ -140,6 +158,7 @@ export const sanitizeFields = ({ config, fields, validRelationships }: Args): Fi
 
         unsanitizedTab.fields = sanitizeFields({
           config,
+          existingFieldNames: tabHasName(tab) ? new Set() : existingFieldNames,
           fields: tab.fields,
           validRelationships,
         })
@@ -159,6 +178,7 @@ export const sanitizeFields = ({ config, fields, validRelationships }: Args): Fi
           config,
           fields: block.fields,
           validRelationships,
+          existingFieldNames: new Set(),
         })
 
         return unsanitizedBlock

test/field-error-states/payload-types.ts

@@ -1,46 +1,225 @@
 /* tslint:disable */
+/* eslint-disable */
 /**
- * This file was automatically generated by Payload CMS.
+ * This file was automatically generated by Payload.
  * DO NOT MODIFY IT BY HAND. Instead, modify your source Payload config,
  * and re-run `payload generate:types` to regenerate this file.
  */
 
 export interface Config {
   collections: {
-    posts: Post
+    'error-fields': ErrorField
+    uploads: Upload
     users: User
+    'payload-preferences': PayloadPreference
+    'payload-migrations': PayloadMigration
   }
   globals: {}
 }
-export interface Post {
+export interface ErrorField {
   id: string
-  arrayField?: {
-    group23field: {
-      arrayField: {
-        group23field: {
-          arrayField: {
-            textField: string
-            id?: string
+  parentArray?:
+    | {
+        childArray: {
+          childArrayText: string
+          id?: string | null
+        }[]
+        id?: string | null
+      }[]
+    | null
+  home: {
+    tabText: string
+    text: string
+    array?:
+      | {
+          requiredArrayText: string
+          arrayText?: string | null
+          group: {
+            text: string
+            number: number
+            date: string
+            checkbox: boolean
+          }
+          code: string
+          json:
+            | {
+                [k: string]: unknown
+              }
+            | unknown[]
+            | string
+            | number
+            | boolean
+            | null
+          email: string
+          /**
+           * @minItems 2
+           * @maxItems 2
+           */
+          point: [number, number]
+          radio: 'mint' | 'dark_gray'
+          relationship: string | User
+          richtext: {
+            [k: string]: unknown
           }[]
+          select: 'mint' | 'dark_gray'
+          upload: string | Upload
+          text: string
+          textarea: string
+          id?: string | null
+        }[]
+      | null
+  }
+  tabText: string
+  text: string
+  array?:
+    | {
+        requiredArrayText: string
+        arrayText?: string | null
+        group: {
+          text: string
+          number: number
+          date: string
+          checkbox: boolean
         }
-        id?: string
+        code: string
+        json:
+          | {
+              [k: string]: unknown
+            }
+          | unknown[]
+          | string
+          | number
+          | boolean
+          | null
+        email: string
+        /**
+         * @minItems 2
+         * @maxItems 2
+         */
+        point: [number, number]
+        radio: 'mint' | 'dark_gray'
+        relationship: string | User
+        richtext: {
+          [k: string]: unknown
+        }[]
+        select: 'mint' | 'dark_gray'
+        upload: string | Upload
+        text: string
+        textarea: string
+        id?: string | null
+      }[]
+    | null
+  layout?:
+    | {
+        tabText: string
+        text: string
+        array?:
+          | {
+              requiredArrayText: string
+              arrayText?: string | null
+              group: {
+                text: string
+                number: number
+                date: string
+                checkbox: boolean
+              }
+              code: string
+              json:
+                | {
+                    [k: string]: unknown
+                  }
+                | unknown[]
+                | string
+                | number
+                | boolean
+                | null
+              email: string
+              /**
+               * @minItems 2
+               * @maxItems 2
+               */
+              point: [number, number]
+              radio: 'mint' | 'dark_gray'
+              relationship: string | User
+              richtext: {
+                [k: string]: unknown
+              }[]
+              select: 'mint' | 'dark_gray'
+              upload: string | Upload
+              text: string
+              textarea: string
+              id?: string | null
+            }[]
+          | null
+        id?: string | null
+        blockName?: string | null
+        blockType: 'block1'
       }[]
-    }
-    id?: string
-  }[]
+    | null
+  group: {
+    text: string
+  }
   updatedAt: string
   createdAt: string
 }
 export interface User {
   id: string
   updatedAt: string
   createdAt: string
-  email?: string
-  resetPasswordToken?: string
-  resetPasswordExpiration?: string
-  salt?: string
-  hash?: string
-  loginAttempts?: number
-  lockUntil?: string
-  password?: string
+  email: string
+  resetPasswordToken?: string | null
+  resetPasswordExpiration?: string | null
+  salt?: string | null
+  hash?: string | null
+  loginAttempts?: number | null
+  lockUntil?: string | null
+  password: string | null
+}
+export interface Upload {
+  id: string
+  text?: string | null
+  media?: string | Upload | null
+  richText?:
+    | {
+        [k: string]: unknown
+      }[]
+    | null
+  updatedAt: string
+  createdAt: string
+  url?: string | null
+  filename?: string | null
+  mimeType?: string | null
+  filesize?: number | null
+  width?: number | null
+  height?: number | null
+}
+export interface PayloadPreference {
+  id: string
+  user: {
+    relationTo: 'users'
+    value: string | User
+  }
+  key?: string | null
+  value?:
+    | {
+        [k: string]: unknown
+      }
+    | unknown[]
+    | string
+    | number
+    | boolean
+    | null
+  updatedAt: string
+  createdAt: string
+}
+export interface PayloadMigration {
+  id: string
+  name?: string | null
+  batch?: number | null
+  updatedAt: string
+  createdAt: string
+}
+
+declare module 'payload' {
+  export interface GeneratedTypes extends Config {}
 }