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useless-exception-statement (PLW0133)#

Derived from the Pylint linter.

Fix is sometimes available.

This rule is unstable and in preview. The --preview flag is required for use.

What it does#

Checks for an exception that is not raised.

Why is this bad?#

It's unnecessary to create an exception without raising it. For example, ValueError("...") on its own will have no effect (unlike raise ValueError("...")) and is likely a mistake.

Known problems#

This rule only detects built-in exceptions, like ValueError, and does not catch user-defined exceptions.



Use instead:

raise ValueError("...")

Fix safety#

This rule's fix is marked as unsafe, as converting a useless exception statement to a raise statement will change the program's behavior.