// Copyright 2025 Don MacAskill. Licensed under MIT or Apache-2.0.

//! This module provides tests and utilities for the CRC library.

#![cfg(test)]

#![allow(dead_code)]

pub(crate) mod consts;

pub(crate) mod enums;

mod future_proof_tests;

mod structs;

use proptest::test_runner::Config as ProptestConfig;

/// Returns a proptest config that works under Miri by disabling file-based failure persistence.

/// Miri runs with isolation enabled by default, which blocks getcwd() calls that proptest

/// uses for its failure persistence feature.

pub(crate) fn miri_compatible_proptest_config() -> ProptestConfig {

    let mut config = ProptestConfig::with_cases(100);

    if cfg!(miri) {

        // don't let Miri spend too much time on these

        config.cases = 1;

        // disable file-based failure persistence to avoid getcwd() calls

        config.failure_persistence = None;

        return config;

    }

    config

}

/// Creates a new aligned data vector from the input slice for testing.

pub(crate) fn create_aligned_data(input: &[u8]) -> Vec<u8> {

    // Size of our target alignment structure

    let align_size = std::mem::size_of::<[[u64; 4]; 2]>(); // 64 bytes

    // Create a zero-filled vector with padding to ensure we can find a properly aligned position

    let mut padded = vec![0; input.len() + align_size];

    // Find the first address that satisfies our alignment

    let start_addr = padded.as_ptr() as usize;

    let align_offset = (align_size - (start_addr % align_size)) % align_size;

    // Copy the input into the aligned position

    let aligned_start = &mut padded[align_offset..];

    aligned_start[..input.len()].copy_from_slice(input);

    // Return the exact slice we need

    aligned_start[..input.len()].to_vec()

}