Prioritizing initial test scripts to converted

It’s the second week of my Outreachy internship, and this week has been focused mainly on reading the email thread that birthed the conversion of the homegrown test scripts to use Clar, understanding the codebase and test structure, as well as prioritizing the test script for initial conversions.

This week, I met with my mentor, who walked me through the code infrastructure via a screen share session. He showed me the intricate details involved in converting a test script to use Clar and how it is wired up in the Git project.

Test scripts classification strategy

I selected four test scripts for initial conversion based on ease and difficulty. The plan is to begin with the easiest test scripts, get some quick, easy wins to become more familiar and comfortable with the test conversions, and build confidence to take on more difficult test scripts.

The following unit test scripts have been selected for conversion:

• t-hash.c
• t-mem-pool.c
• t-prio-queue.c
• t-reftable-tree.c

The above unit test scripts were selected on the basis of their code lines as well as the number of test functions they contain.

t-hash.c

This test file validates the correctness of SHA1 and SHA256 hash computations in the Git project. The cmd_main function initializes string buffers with specific test data and uses macros to run hash tests. The check_hash_data function computes hashes for given inputs and compares them to expected values, logging errors if discrepancies are found.

The tests cover various cases, including empty strings, single characters, phrases, long repeated patterns, and strings with embedded NUL characters. By comparing the computed hashes against known values, the file ensures the reliability and accuracy of the Git project’s hash functions, which are crucial for maintaining data integrity and security.

t-mem-pool.c

t-mem-pool.c ensures the proper functionality of the mem_pool memory allocation system in the Git project. It includes a main function cmd_main that sets up memory pools with different block sizes and uses a helper function to verify that memory allocation and initialization work correctly. The setup_static function initializes a memory pool, calls a specified test function, and then discards the pool to clean up.

The specific test function, t_calloc_100, allocates a 100-byte buffer from the memory pool and checks that all bytes are zeroed out. It also verifies the integrity of the memory pool’s internal structures. The main function runs this test with both a large block size (1 MB) and a small block size (1 byte), ensuring that the mem_pool system can handle different allocation scenarios reliably.

t-prio-queue.c

This test file verifies the functionality of the priority queue prio_queue in the Git project. It includes a main function cmd_main that defines several test cases, each with specific input sequences and expected results. The test_prio_queue function processes these inputs using various priority queue operations and compares the output against the expected results. It handles commands to insert elements, retrieve the highest priority element, dump all elements, treat the queue as a stack, and reverse the queue order.

The intcmp function is used for integer comparison within the priority queue, while macros and helper functions facilitate the testing process. The tests cover different scenarios: basic priority queue operations, mixed insert and retrieve commands, handling an empty queue, using the queue as a LIFO stack, and reversing the stack.

t-reftable-tree.c

This ensures the functionality of the tree operations in the reftable component of the Git project. It includes two main test functions, t_tree_search and t_infix_walk, which validate the insertion, search, and traversal operations of a binary tree. The cmd_main function runs these tests and checks their outcomes.

The t_tree_search function tests the insertion of elements into a tree and verifies that the inserted nodes can be correctly searched. It uses a pseudo-random sequence to insert elements and checks that each inserted element is correctly stored and retrievable. The t_infix_walk function validates the in-order traversal of the tree. It inserts elements, performs an in-order traversal, and checks that the elements are visited in the correct order. Both tests ensure that the tree functions behave as expected, maintaining the integrity and correctness of the tree operations.

Next steps

The next step would include getting a clearer understanding of the above-selected unit test scripts as well as the test structure. After this, I would begin playing around with the unit test scripts and carry out the first iteration of the test conversion.

Feel free to give your input and suggestions, as this can help point to whatever I may be missing or not doing enough of. Thanks!