Skip to main content

Assert violation

Description​

  • Category: Validations and error handling
  • Severity: Enhancement
  • Detectors: assert-violation

The assert! macro is used in Rust to ensure that a certain condition holds true at a certain point in your code.

Why is this bad?​

The assert! macro can cause the contract to panic. It is recommended to avoid this, because it stops its execution, which might lead the contract to an inconsistent state if the panic occurs in the middle of state changes. Additionally, the panic could cause a transaction to fail.

Example​

Consider the following snippet code:

pub fn assert_if_greater_than_10(_env: Env, value: u128) -> bool {
    assert!(value <= 10, "value should be less than 10");
    true
}

Remediated example​

Consider using a proper error and return it:

pub fn assert_if_greater_than_10(_env: Env, value: u128) -> Result<bool, AVError> {
    if value <= 10 {
        Ok(true)
    } else {
        Err(AVError::GreaterThan10)
    }
}

How is it detected?​

Checks for assert! macro usage.