You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: aesavs.rs
    path of file: ./repos/OpenSK/libraries/crypto/tests
    
    the code of the file until where you have to start completion: // Copyright 2019 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

/// Test vectors for AES-ECB from NIST's validation suite.
///
/// See also https://csrc.nist.gov/CSRC/media/Projects/Cryptographic-Algorithm-Validation-Program/documents/aes/AESAVS.pdf
use arrayref::array_ref;
use crypto::aes256;
use regex::Regex;
use std::fs::File;
use std::io::{BufRead, BufReader};
use std::path::Path;

#[test]
fn aesavs() {
    // These data files are taken from https://csrc.nist.gov/groups/STM/cavp/documents/aes/KAT_AES.zip.
    test_aesavs_file("tests/data/ECBVarKey256.rsp");
    test_aesavs_file("tests/data/ECBVarTxt256.rsp");
}

fn test_aesavs_file<P: AsRef<Path>>(path: P) {
    // Implements some custom parsing for NIST's test vectors.
    let re_count = Regex::new("^COUNT = ([0-9]+)$").unwrap();
    let re_key = Regex::new("^KEY = ([0-9a-f]{64})$").unwrap();
    let
    
fn test_aesavs_file<P: AsRef<Path>>(path: P) {
    // Implements some custom parsing for NIST's test vectors.
    let re_count = Regex::new("^COUNT = ([0-9]+)$").unwrap();
    let re_key = Regex::new("^KEY = ([0-9a-f]{64})$").unwrap();
    let re_plaintext = Regex::new("^PLAINTEXT = ([0-9a-f]{32})$").unwrap();
    let re_ciphertext = Regex::new("^CIPHERTEXT = ([0-9a-f]{32})$").unwrap();

    let file = BufReader::new(File::open(path).unwrap());
    let mut lines = file.lines();

    loop {
        let line = lines.next().unwrap().unwrap();
        if line == "[ENCRYPT]" {
            break;
        }
    }

    for i in 0.. {
        // empty line
        let line = lines.next().unwrap().unwrap();
        assert_eq!(line, "");

        let line = lines.next().unwrap().unwrap();
        if line == "[DECRYPT]" {
            // Skip the decryption tests, they are the same as the encryption tests.
            break;
        }
        // "COUNT = "
        let captures = re_count.captures(&line).unwrap();
        let count = captures.get(1).unwrap().as_str().parse::<usize>().unwrap();
        assert_eq!(count, i);

        // "KEY = "
        let line = lines.next().unwrap().unwrap();
        let captures = re_key.captures(&line).unwrap();
        let key = hex::decode(captures.get(1).unwrap().as_str()).unwrap();
        assert_eq!(key.len(), 32);

        // "PLAINTEXT = "
        let line = lines.next().unwrap().unwrap();
        let captures = re_plaintext.captures(&line).unwrap();
        let plaintext = hex::decode(captures.get(1).unwrap().as_str()).unwrap();
        assert_eq!(plaintext.len(), 16);

        // "CIPHERTEXT = "
        let line = lines.next().unwrap().unwrap();
        let captures = re_ciphertext.captures(&line).unwrap();
        let ciphertext = hex::decode(captures.get(1).unwrap().as_str()).unwrap();
        assert_eq!(ciphertext.len(), 16);

        {
            let encryption_key = aes256::EncryptionKey::new(array_ref![key, 0, 32]);
            let mut block: [u8; 16] = [Default::default(); 16];
            block.copy_from_slice(&plaintext);
            encryption_key.encrypt_block(&mut block);
            assert_eq!(&block, ciphertext.as_slice());
        }

        {
            let encryption_key = aes256::EncryptionKey::new(array_ref![key, 0, 32]);
            let decryption_key = aes256::DecryptionKey::new(&encryption_key);
            let mut block: [u8; 16] = [Default::default(); 16];
            block.copy_from_slice(&ciphertext);
            decryption_key.decrypt_block(&mut block);
            assert_eq!(&block, plaintext.as_slice());
        }
    }
}