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Support for optional object properties

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Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
35/100
Issue type
Feature
Clarity
Mostly clear
Activity status
Stale
Tech stack
javascript
Domain
backend

Research direction

No files, tests, or entry points are named. Reproduce the supplied fact and rule with the missing title and with an empty object array, then trace the JSON path and doesNotContain evaluation; done means the requested optional-property cases return the expected result without requiring a custom operator.

Written by the indexing model from the issue text.

Description

Let's say we have the following Fact:

{
  "firstName": "John",
  "lastName" : "doe",
  "age"      : 26,
  "address"  : {
    "streetAddress": "naist street",
    "city"         : "Nara",
    "postalCode"   : "630-0192"
  },
  "phoneNumbers": [
    {
      "type"  : "iPhone",
      "number": "0123-4567-8888"
    },
    {
      "type"  : "home",
      "number": "0123-4567-8910"
    }
  ]
}

The following rule snippet should return true in my understanding:

  {
                fact: 'a',
                path: `$..phoneNumbers..title`,
                operator: 'doesNotContain',
                value: 'SOMETITLE'
            },

However this will evaluate to false, as "title" is not present in the object.
The actual use case I have is that the dynamic fact ist an array of objects which can be an empty array sometimes (due to input params for the fact).

Supporting this use case would be very valuable, otherwise additional custom operators are necessary.

Dominant language
JavaScript
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