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Option to include `init=False` globally on a converter, not per class

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
35/100
Issue type
Feature
Clarity
Mostly clear
Activity status
Stale
Tech stack
python
Domain
backend

Research direction

Start with cattrs.Converter and the cattrs.strategies.include_init_false entry point mentioned in the issue, then inspect how converter configuration affects attrs classes. Verify the chosen global option with structure and unstructure examples containing init=False fields, and add coverage showing the old behavior is enabled for multiple classes.

Written by the indexing model from the issue text.

Description

documentation
  • cattrs version: v23.2.3
  • Python version: 3.11.6
  • Operating System: Ubuntu
Description

On previous cattrs versions, I used to structure and unstructure a lot of attrs classes that had many init=False fields.

Now, though, with the new versions of cattrs (v23.2.0), this behavior changed, breaking my code.

I'd like to be able to enable the old behavior back globally on a converter, instead of having to enable it for every single class, as I have many classes all over the place that would benefit from re-enabling init=False fields in conversion.

import attrs
import cattrs


@attrs.define
class Foo:
    bar: int
    baz: str = attrs.field(init=False)


foo = Foo(bar=1)
foo.baz = "hello"


converter = cattrs.Converter()
print(converter.unstructure(foo))
# before: {'bar': 1, 'baz': 'hello'}
# after: {'bar': 1}

I thought about something like this:

import cattrs
from cattrs.strategies import include_init_false

converter = cattrs.Converter()
include_init_false(converter)

# OR

converter = cattrs.Converter(include_init_false=True)
Dominant language
Python
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