Chess-Lib

Development

Init

Enable the git pre-commit hook using: chmod +x .githooks/pre-commit && git config --local core.hooksPath

Testing

To run all test use cargo test. This will also run the more expensive tests. During development you can use cargo test --no-default-features to run only the faster tests.

Code Generation

Generate magic entries: cargo run --release chess generate > /tmp/magics_entries.rs && mv /tmp/magics_entries.rs src/engine/chess/magics_entries.rs

Debugging

Profiling

For an initial look we can create a flamegraph using cargo-flamegraph on Linux by running: cargo build --release && flamegraph -o my_flamegraph.svg -- target/release/chess-lib chess perft --fen "r3k2r/p1ppqpb1/bn2pnp1/3PN3/1p2P3/2N2Q1p/PPPBBPPP/R3K2R w KQkq -" --depth 5

For profiling we can use perf on Linux. Run the perft command with perf record and profile until it exits: cargo build --release && perf record -F99 --call-graph dwarf target/release/chess-lib chess perft --fen "r3k2r/p1ppqpb1/bn2pnp1/3PN3/1p2P3/2N2Q1p/PPPBBPPP/R3K2R w KQkq -" --depth 5

This will output a file called perf.data.

To view the profiling results you use perf report and to view a specific data file you can use perf report -i <path-to-perf-data-file>.

Or to compare to reports you can use perf diff <path-to-base-line-perf-data-file> <path-to-new-perf-data-file>

Stockfish & Perft

Stockfish

Download Stockfish and compile it using make -j build ARCH=x86-64-modern. Then run ./stockfish

You can enter a specific FEN using e.g. position fen rnbqkbnr/1ppppppp/p7/8/8/7P/PPPPPPP1/RNBQKBNR w KQkq - 0 1

You can also visualize this by entering d

Then to run perft with a specific depth (e.g. 3) enter go perft 3

Perft

Run eg. `cargo run --release chess perft --fen "rnbqkbnr/1ppppppp/p7/8/8/7P/PPPPPPP1/RNBQKBNR w KQkq - 0 1" --depth 3

Debugging

First compile a release build doing cargo build --release

There is a debugging script which can be run using this command: python perft.py <path-to-stockfish-executable> <path-to-rechess-engine-executable> "<fen>" <depth>

Publishing

To publish a new version of the crate you need to do the following:

1. Update the version in Cargo.toml for version and documentation
2. Run cargo test to ensure all tests pass
3. Inspect the generate documentation by running cargo doc --no-deps --open
4. Git commit the changes
5. Run cargo publish --dry-run to ensure there aren’t any warnings or errors before publishing.
6. Inspect the generated .crate by running cargo package --list
7. Run cargo publish to publish the crate to crates.io