invalid-match-args-definition / E1902

Message emitted:

`__match_args__` must be a tuple of strings.

Description:

Emitted if `__match_args__` isn't a tuple of strings required for match.

Problematic code:

class Book:
    __match_args__ = ["title", "year"]  # [invalid-match-args-definition]

    def __init__(self, title, year):
        self.title = title
        self.year = year

Correct code:

class Book:
    __match_args__ = ("title", "year")

    def __init__(self, title, year):
        self.title = title
        self.year = year

Related links:

• Python documentation

Created by the match_statements checker.