Add B044: assert <generator_expression>

[gschaffner]

Closes #534.

[Copilot]

Pull request overview

This PR adds a new flake8-bugbear check B044 to detect assert <generator_expression> patterns, which are always truthy and likely indicate a bug where the developer forgot to wrap the generator in all() or any().

Key Changes:

• Adds check B044 to detect generator expressions used directly in assert statements
• Includes test cases covering generator expressions and other comprehension types

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
tests/eval_files/b044.py	Adds test cases for B044 check, including positive case (generator expression) and negative cases (list/set/dict comprehensions)
bugbear.py	Implements check_for_b044() method, integrates it into visit_Assert(), and defines the B044 error message
README.rst	Documents the new B044 check and adds changelog entry

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[Copilot]

The test file should include a test case for assert <generator_expression>, "message" to ensure the check works correctly when the assert statement includes an error message. This is a common pattern in assertions and should be tested, similar to how B011 tests both assert False and assert False, "message".

[Copilot]

Consider adding test cases for edge cases such as:

• Nested generator expressions: assert (x for x in (y for y in a))
• Generator expressions in boolean context with 'and'/'or': assert some_condition and (x for x in a)
• Generator expressions with conditions: assert (x for x in a if x > 0)

These scenarios would help ensure the check correctly identifies all problematic patterns.

[JelleZijlstra]

I wonder if it would make sense to broaden this into asserts with other constructs that we can statically detect will always be true, such as nonempty list literals.