auth.userUpdate() overwrite the original object

[Karman40]

[REQUIRED] Step 2: Describe your environment

• Operating System version: WIN11
• Firebase SDK version: 10.3.0 (admin)
• Firebase Product: auth
• Node.js version: v16
• NPM version: _____

[REQUIRED] Step 3: Describe the problem

Relevant Code:

console.log(body);
await auth.updateUser(param.id, body);
console.log(body);

Body before auth.updateUser

UserUpdateDto {
  email: '[email protected]',
  displayName: 'Basecloud',
  phoneNumber: null,
  role: 'user',
  emailVerified: true,
  disabled: false,
  mfaRequired: false,
  needChangePassword: false
}

Body after auth.updateUser

UserUpdateDto {
  email: '[email protected]',
  displayName: 'Basecloud',
  emailVerified: true,
  localId: '62a66160b651fe47a7cdde20',
  deleteProvider: [ 'phone' ],
  disableUser: false
}

Soft bug fix

console.log(body);
await auth.updateUser(param.id, { ...body });
console.log(body);

Why does the user update overwrite the original object?