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assert (S101)

Added in v0.0.116 · Related issues · View source

Derived from the flake8-bandit linter.

What it does

Checks for uses of the assert keyword.

Why is this bad?

Assertions are removed when Python is run with optimization requested (i.e., when the -O flag is present), which is a common practice in production environments. As such, assertions should not be used for runtime validation of user input or to enforce interface constraints.

Consider raising a meaningful error instead of using assert.

Example

assert x > 0, "Expected positive value."

Use instead:

if not x > 0:
    raise ValueError("Expected positive value.")

# or even better:
if x <= 0:
    raise ValueError("Expected positive value.")