Method Could Be Static

python.method_could_be_static

Severity

low

Remediation Complexity

trivial

Remediation Risk

low

Remediation Effort

low

Resource

Best Practice

Language

Python

Description

Reports instance methods whose body never references self. Such methods do not depend on any instance state and can be marked @staticmethod, which makes the lack of dependency explicit, lets callers invoke them via Cls.method(…) without instantiating, and slightly reduces per-call overhead.

class Foo:
    def helper(self, x):       # FLAW — body never uses self
        return x * 2

    def method(self):
        return self.helper(self.value)

Rationale

A method that takes self but never reads or writes through it is a method the class structure does not justify. Promoting it to @staticmethod documents the truth and prevents future maintenance from accidentally introducing a self.X reference that ties the helper to the class state.

The rule is conservative: it skips methods decorated with @staticmethod, @classmethod, @property, or any of the @abstractXxx family, and it skips dunder methods (init, eq, repr, …) since the data model often requires them to be instance methods even when their implementation ignores self.

Remediation

Add the @staticmethod decorator and drop the self parameter:

class Foo:
    @staticmethod
    def helper(x):
        return x * 2

If the method really should depend on instance state, the fix is the other direction — make it use self.

References

Python — staticmethod