MongoEngine / MongoEngine/mongoengine

LazyReferenceField requires check for None before using fetch() or pk

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Dominant language
Python
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Description

Hello, I'm relatively new to MongoEngine so I apologize in advance if this is a bad idea for some reason. That said, it seems like using LazyReferenceField would be much nicer if one didn't have to to check whether the field has a value before calling fetch() or accessing pk. Why not just have build_lazyref() allow for None to be passed on as the value of the LazyReference, and then have LazyReference.fetch() return None if self.id = None?

I'm willing to try setting up a dev environment and creating a PR for this if people think it's a good suggestion. Thanks for reading!

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Research direction

Start by locating build_lazyref() and LazyReference.fetch(), then trace how LazyReference exposes pk when the referenced value is absent. The requested behavior is to allow None and have fetch() and pk access return None; confirm the existing LazyReference behavior before determining the needed coverage.

Written by the indexing model from the issue text.

Assessment

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

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