Error in eqJoin map function when returning object with $loki

[jmhmd]

I am trying out the eqJoin function for the first time, and was running into an error when trying to combine the left and right objects in the mapper function.

When I tried to use object spread syntax to add a field to left from right:

const stagedJobs = db.jobs
    .chain()
    .find({
      status: { $in: ['staged', 'error', 'processing'] },
    })
    .eqJoin(db.users, 'userId', '$loki', (left, right) => {
       return { ...left, username: right.username }; 👈 
    })
    .data();

I get the error:

Error: Document is already in collection, please use update()
    at Collection.add (/Users/jasonhostetter/dev/pacsbin-project/rigel/node_modules/lokijs/src/lokijs.js:5951:15)
    at Collection.insertOne (/Users/jasonhostetter/dev/pacsbin-project/rigel/node_modules/lokijs/src/lokijs.js:5738:17)
    at Collection.insert (/Users/jasonhostetter/dev/pacsbin-project/rigel/node_modules/lokijs/src/lokijs.js:5686:20)
    at Resultset.eqJoin (/Users/jasonhostetter/dev/pacsbin-project/rigel/node_modules/lokijs/src/lokijs.js:3961:23)

I figured out that it depends on whether I am trying to pass $loki as a field in the returned object.

This gives an error:

.eqJoin(db.users, 'userId', '$loki', (left, right) => {
      return {
        $loki: left.$loki, 👈 
        username: right.username,
        description: left.description,
        studies: left.studies,
        status: left.status,
      };
    })

This works as expected:

.eqJoin(db.users, 'userId', '$loki', (left, right) => {
      return {
        jobId: left.$loki, 👈 
        username: right.username,
        description: left.description,
        studies: left.studies,
        status: left.status,
      };
    })

Is there a way to just add a field or fields to the left object of the join and return it?

[stale[bot]]

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