dosisod/refurb v1.22.0

on GitHub

This version adds 2 new checks, some bug fixes, and documentation fixes.

Improved Error Messages

Previously Refurb would assume certain identifiers such as Path where imported as Path, not pathlib.Path. This made the context of error messages less helpful since they did not reflect what was actually in the source. Now more checks will use the more accurate pathlib.Path identifier if needed.

Add use-chain-from-iterable check (FURB179)

When flattening a list of lists, use the chain.from_iterable function from the itertools stdlib package. This function is faster than native list/generator comprehensions or using sum() with a list default.

Bad:

from itertools import chain

rows = [[1, 2], [3, 4]]

# using list comprehension
flat = [col for row in rows for col in row]

# using sum()
flat = sum(rows, [])

# using chain(*x)
flat = chain(*rows)

Good:

from itertools import chain

rows = [[1, 2], [3, 4]]

flat = chain.from_iterable(rows)

Note: chain(*x) may be marginally faster/slower depending on the length of x. Since * might potentially expand to a lot of arguments, it is better to use chain.from_iterable() when you are unsure.

Add use-abc-shorthand check (FURB180)

Instead of setting metaclass directly, inherit from the ABC wrapper class. This is semantically the same thing, but more succinct.

Bad:

class C(metaclass=ABCMeta):
    pass

Good:

class C(ABC):
    pass

What's Changed

• Don't emit FURB120 when deleting default arg would change semantics by @dosisod in #289
• Update docs for FURB107 (use-suppress) by @dosisod in #292
• Add use-chain-from-iterable check by @dosisod in #293
• Tweak versioning docs, bump packages by @dosisod in #294
• Fix failing test in Mypy 1.6.0 by @dosisod in #296
• Bump packages, bump version by @dosisod in #297

Full Changelog: v1.21.0...v1.22.0