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Hypothesis integration

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#234 2 comments 1 reaction 0 assignees View on GitHub

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Assessment

Difficulty
5/5
Estimated time
Over a week
Newbie friendliness
25/100
Issue type
Feature
Clarity
Mostly clear
Activity status
Stale
Tech stack
python
Domain
testing

Research direction

Start by reading the referenced returns/contrib/hypothesis/laws.py and compare it with the existing typeclass and mypy checks in this project. Define the proposed check_typeclass strategy and its allow_instances, allow_protocols, and allow_unknown options, then verify supported cases produce valid return types and unsupported cases produce NotImplementedError.

Written by the indexing model from the issue text.

Description

enhancement

Right now we don't test classes with hypothesis at all.

But, I have a great idea (at least it seems to me like so) of adding a hypothesis plugin, similar to one we have in returns: https://github.com/dry-python/returns/blob/master/returns/contrib/hypothesis/laws.py

What should it do?

  • check_typeclass(typeclass_instance) will check that for all existing types and protocols some valid return type is produced. For example, @typeclass def some(instance) -> str must produce str for all instance, protocol, and supported types and it must produce NotImplementedError for types that are not supported
  • Looks like check_typeclass must have allow_instances, allow_protocols, allow_unknown kw bool arguments to configure what types we actually need in a resulting strategy

It would be a nice companion to our mypy check.

@Zac-HD do you like it? Maybe you have any other ideas?

Dominant language
Python
Stars
730
Forks
30
No merged PRs in 30d

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First steps

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  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

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