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"in" operator errors out if array value data is null or undefined; Should return false

See original GitHub issue

Given the following rule:

{ "in": [ "1", { "var": "MyData.Values" } ] }

Using it on the following data will cause an error when, IMO, it should return false;

   "MyData": {
      "Values": null

Should be easy enough to check for a null/undefined data set before testing the “in” operation and return false if necessary.

This may also be a problem with other supported array operations. Although, I have not tested them to see.

Issue Analytics

  • State:open
  • Created 6 years ago
  • Comments:5 (1 by maintainers)

github_iconTop GitHub Comments

jwadhamscommented, Oct 18, 2017

I can work on this, you’re right it’s going to make the library more robust.

In the meantime you might be able to make your rules more robust by using an empty array as your default in your var calls, like

{ "in": [ 
  { "var": ["MyData.Values", [] ] } 
] }
MaxNodlandcommented, Oct 25, 2017

Came to report this bug. I fixed locally by adding a “safeIn” function

jsonLogic.add_operation('safeIn', (a, b) => { if(!b || typeof b.indexOf === "undefined") return false; return (b.indexOf(a) !== -1); } )

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