refactor: prevent custom field overriding prototype property

packages/utils/index.ts

@@ -61,7 +61,7 @@ export { checkRegex, regex } from './src/regex-utils/checkRegex.js';
 export { isColourHex } from './src/regex-utils/isColourHex.js';
 export { splitWhitespace } from './src/regex-utils/splitWhitespace.js';
 
-export { customFieldLabelToKey, customKeyFromLabel } from './src/customField-utils/customFieldUtils.js';
+export { customFieldLabelToKey, customKeyFromLabel, isObjectPrototypeKey } from './src/customField-utils/customFieldUtils.js';
 
 // helpers from externals
 export { deepmerge } from './src/externals/deepmerge.js';

packages/utils/src/customField-utils/customFieldUtils.ts

@@ -1,5 +1,7 @@
 import type { CustomFields } from 'ontime-types';
 
+const objectPrototypeKeys = new Set(Object.getOwnPropertyNames(Object.prototype));
+
 /**
  * Transforms an alphanumeric label with spaces into a valid key
  */
@@ -7,6 +9,13 @@ export function customFieldLabelToKey(label: string): string {
   return label.trim().replaceAll(' ', '_');
 }
 
+/**
+ * Detects keys that collide with Object prototype properties or methods
+ */
+export function isObjectPrototypeKey(key: string): boolean {
+  return objectPrototypeKeys.has(key);
+}
+
 /**
  * Finds an object key in the CustomFields object that matches the given label
  */