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zip-without-explicit-strict (B905)

Derived from the flake8-bugbear linter.

Fix is always available.

What it does

Checks for zip calls without an explicit strict parameter.

Why is this bad?

By default, if the iterables passed to zip are of different lengths, the resulting iterator will be silently truncated to the length of the shortest iterable. This can lead to subtle bugs.

Pass strict=True to raise a ValueError if the iterables are of non-uniform length. Alternatively, if the iterables are deliberately different lengths, pass strict=False to make the intention explicit.

Example

zip(a, b)

Use instead:

zip(a, b, strict=True)

Fix safety

This rule's fix is marked as unsafe for zip calls that contain **kwargs, as adding a strict keyword argument to such a call may lead to a duplicate keyword argument error.

References