Condition using $exists doesn't behave as expected

[egmacke]

Describe the bug

Given a rule that defines a nested field should not exist (i.e. $exists: false) it behaves as expected if all nesting up to the relevant field is present, but if the parent field also does not exist, then it returns incorrectly (for clarification see below)

To Reproduce This is a contrived example, but illustrates the problem.

import { defineAbility } from '@casl/ability';

const ability = defineAbility(can => {
  can('read', 'User', {
    'group.objectId': { $exists: false }
  });
});

console.log(
  ability.can(
    'read',
    subject('User', {
      group: {
        objectId: 'JgtM0H1IH5'
      }
    })
  )
); // > false - as expected

console.log(
  ability.can(
    'read',
    subject('User', {
      group: {
        
      }
    })
  )
); // > true - as expected

console.log(
  ability.can(
    'read',
    subject('User', {
    })
  )
); // > false - not expected. `group.objectId` does not exists so rule should return true.

Expected behavior Rules with the condition $exists: false should always resolve when field is not present regardless of if parent exists or not.

Interactive example (optional, but highly desirable) https://replit.com/@egmackenzie1/CaslJS-bug-report#index.js

CASL Version

@casl/ability - v6.5.0

Environment: NodeJS

[marik22312]

Getting the same behavior, on 6.3.3

[stalniy]

fixed in https://github.com/stalniy/ucast/commit/ec1c7d6a82bee22dd5c26779f92ff2b5aaf2efb5 Will take some time to publish a new version, plan to do it till the end of the week

[stalniy]

@ucast/[email protected] has been published. The issue should be fixed. ensure to update your lock file.

Close the issue, in case of any issues, please do not hesitate to report it here