marshmallow-code/marshmallow

Type hinting for `load` is too strict

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#1,457 opened on Nov 12, 2019

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 (12 comments) (0 reactions) (0 assignees)Python (640 forks)batch import
help wantedtyping

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Description

The type hinting for load's data argument is set to typing.Mapping which makes sense for the many=False case, but for many=True case the type of data is list, which isn't a Mapping type.

Contributor guide

Research direction
Examine the type hint for the `data` parameter in the `load` method, and determine how to correctly type it to accept both `Mapping` (for single objects) and `list` (for lists of objects when `many=True`). Consider using `typing.Union` or overloads.
Tech stack
python
Domain
backendapi
Issue type
Bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Mostly clear
Prerequisites
Pythontype hints
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
65