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convert-named-tuple-functional-to-class (UP014)

Added in v0.0.155 · Related issues · View source

Derived from the pyupgrade linter.

Fix is sometimes available.

What it does

Checks for NamedTuple declarations that use functional syntax.

Why is this bad?

NamedTuple subclasses can be defined either through a functional syntax (Foo = NamedTuple(...)) or a class syntax (class Foo(NamedTuple): ...).

The class syntax is more readable and generally preferred over the functional syntax, which exists primarily for backwards compatibility with collections.namedtuple.

Example

from typing import NamedTuple

Foo = NamedTuple("Foo", [("a", int), ("b", str)])

Use instead:

from typing import NamedTuple


class Foo(NamedTuple):
    a: int
    b: str

Fix safety

This rule's fix is marked as unsafe if there are any comments within the range of the NamedTuple definition, as these will be dropped by the autofix.

References