fix: fixed keychain string creation for keychains with zeros

module/src/form/utils/keyChain.spec.ts

@@ -2,6 +2,7 @@ import {
   childKeyChainStringFromParent,
   isArrayValue,
   isMyKeyChainItem,
+  isValidPropertyKey,
   keyStringFromKeyChain,
   mergeDeepFromKeyChain,
   valueByKeyChain,
@@ -204,6 +205,38 @@ describe('isArrayValue', () => {
   });
 });
 
+describe('isValidPropertyKey', () => {
+  it('returns true for a valid string key', () => {
+    const key = 'validKey';
+    const result = isValidPropertyKey(key);
+    expect(result).toBeTruthy();
+  });
+
+  it('returns true for a valid number key', () => {
+    const key = 123;
+    const result = isValidPropertyKey(key);
+    expect(result).toBeTruthy();
+  });
+
+  it('returns true for 0 as a valid number key', () => {
+    const key = 0;
+    const result = isValidPropertyKey(key);
+    expect(result).toBeTruthy();
+  });
+
+  it('returns false for an empty string key', () => {
+    const key = '';
+    const result = isValidPropertyKey(key);
+    expect(result).toBeFalsy();
+  });
+
+  it('returns false for undefined key', () => {
+    const key = undefined;
+    const result = isValidPropertyKey(key);
+    expect(result).toBeFalsy();
+  });
+});
+
 /* validationKeyStringFromKeyChain */
 describe('keyStringFromKeyChain', () => {
   it('converts a keychain to dot notation to target an item stored by keychain string', () => {
@@ -212,6 +245,12 @@ describe('keyStringFromKeyChain', () => {
     expect(result).toBe('test.value.3.target');
   });
 
+  it('converts a keychain to dot notation to target an item stored by keychain string when the keychain containes a zero', () => {
+    const keyChain = ['test', 'value', 0, 'target'];
+    const result = keyStringFromKeyChain(keyChain, 'dots');
+    expect(result).toBe('test.value.0.target');
+  });
+
   it('converts a keychain to bracket notation to target an item stored by keychain string', () => {
     const keyChain = ['test', 'value', 3, 'target'];
     const result = keyStringFromKeyChain(keyChain, 'brackets');

module/src/form/utils/keyChain.ts

@@ -109,6 +109,15 @@ export function isArrayValue(value: unknown, attemptedAction: string): value is
   return true;
 }
 
+/**
+ * Checks a possible keyChain to make sure it is a valid keyChain.
+ * @param keyChain The keyChain to check.
+ * @returns true if the keyChain is valid, false if not.
+ */
+export function isValidPropertyKey(propertyKey: PropertyKey | undefined): propertyKey is PropertyKey {
+  return typeof propertyKey === 'number' || (typeof propertyKey === 'string' && propertyKey.length > 0);
+}
+
 /**
  * Converts a keyChain into a key string
  * @param keyChain The chain of keys passed to `formProp` and used to access the property within a nested form object.
@@ -118,7 +127,7 @@ export function isArrayValue(value: unknown, attemptedAction: string): value is
 export function keyStringFromKeyChain(keyChain: KeyChain | undefined, mode: 'dots' | 'brackets'): string {
   switch (mode) {
     case 'dots':
-      return keyChain?.filter(key => !!key).join('.') ?? '';
+      return keyChain?.filter(isValidPropertyKey).join('.') ?? '';
     case 'brackets':
       return (
         keyChain?.reduce<string>((attrString, key) => {