Type of client.run() with filter_single incorrectly inferred as array

[jvassev]

Code The code causing the error.

async function test(client, id: string) {
  const myWidget = await e.select(e.default.Widget, () => ({
    filter_single: { id: id },
  })).run(client);

  // myWidget inferred as Array<{id: string}>
  if (!Array.isArray(myWidget)) {
    throw new Error("expected an array");
  }
}

Schema

Your application schema.

module default {
  type Widget {
    name: str;
  }
}

Generated EdgeQL

No errors in edgeql

Error or desired behavior

No errors at compile time. At runtime, I expect an array of objects, however I get either null of a single element. I thinks it better to fix the inferred type to be T | null or wrap the single result in an array.

Is there a workaround for this. Now I'm using const myWidget: any to

Versions (please complete the following information):

• OS:
• EdgeDB version (e.g. 2.0): edgedb/edgedb:3 (docker image)
• EdgeDB CLI version (e.g. 2.0): EdgeDB CLI 3.4.0+160d07d
• edgedb-js version (e.g. 0.20.10;): 1.3.4
• @edgedb/generate version (e.g. 0.0.7;): 0.3.3
• Typescript version: 5.1.3
• Node/Deno version: v16.15.0

[scotttrinh]

Yeah, I noticed that a while back, thanks for reporting. In the meantime, you can work around this by wrapping in e.assert_single(e.assert_exists(yourQuery)). Will fix!

[scotttrinh]

Might be related to #715

[sharifzadesina]

I don't understand this issue, right now if you use filter_single the result is T | null, what is wrong with this?

[scotttrinh]

Oh, sorry, I think I misunderstood the original report: filter_single will indeed give you T | null as @sharifzadesina pointed out, so this is working as intended.