For contributing rules and best practices please refer to CONTRIBUTING.md
For this guide we assume that you already have a GitHub account and have git
and your favorite code editor or IDE installed and configured.
Before you start working on coreutils, please follow these steps:
- Fork the coreutils repository to your GitHub account. Tip: See this GitHub guide for more information on this step.
- Clone that fork to your local development environment:
git clone https://github.com/YOUR-GITHUB-ACCOUNT/coreutils
cd coreutils
You will need the tools mentioned in this section to build and test your code changes locally. This section will explain how to install and configure these tools. We also have an extensive CI that uses these tools and will check your code before it can be merged. The next section Testing will explain how to run those checks locally to avoid waiting for the CI.
If you're using rustup to install and manage your Rust toolchains, clippy
and rustfmt
are usually already installed. If you are using one of the alternative methods, please make sure to install them manually. See following sub-sections for their usage: clippy rustfmt.
Tip You might also need to add 'llvm-tools' component if you are going to generate code coverage reports locally:
rustup component add llvm-tools-preview
If you are developing on Linux, most likely you already have all/most GNU utilities and prerequisites installed.
To make sure, please check GNU coreutils README-prereq.
You will need these to run uutils against the GNU test suite locally.
For MacOS and Windows platform specific setup please check MacOS GNU utils and Windows GNU utils sections respectfully.
A configuration for pre-commit
is provided in the repository. It allows
automatically checking every git commit you make to ensure it compiles, and
passes clippy
and rustfmt
without warnings.
To use the provided hook:
- Install
pre-commit
- Run
pre-commit install
while in the repository directory
Your git commits will then automatically be checked. If a check fails, an error
message will explain why, and your commit will be canceled. You can then make
the suggested changes, and run git commit ...
again.
NOTE: On MacOS the pre-commit hooks are currently broken. There are workarounds involving switching to unstable nightly Rust and components.
cargo clippy --all-targets --all-features
The msrv
key in the clippy configuration file clippy.toml
is used to disable
lints pertaining to newer features by specifying the minimum supported Rust
version (MSRV).
cargo fmt --all
This project uses cargo-deny to detect duplicate dependencies, checks licenses, etc. To run it locally, first install it and then run with:
cargo deny --all-features check all
We use markdownlint to lint the Markdown files in the repository.
We use cspell
as spell checker for all files in the project. If you are using
VS Code, you can install the
code spell checker
extension to enable spell checking within your editor. Otherwise, you can
install cspell separately.
If you want to make the spell checker ignore a word, you can add
// spell-checker:ignore word_to_ignore
at the top of the file.
This section explains how to run our CI checks locally.
Testing can be done using either Cargo or make
.
Just like with building, we follow the standard procedure for testing using Cargo:
cargo test
By default, cargo test
only runs the common programs. To run also platform
specific tests, run:
cargo test --features unix
If you would prefer to test a select few utilities:
cargo test --features "chmod mv tail" --no-default-features
If you also want to test the core utilities:
cargo test -p uucore -p coreutils
# or
cargo test --all-features -p uucore
Running the complete test suite might take a while. We use nextest in the CI and you might want to try it out locally. It can speed up the execution time of the whole test run significantly if the cpu has multiple cores.
cargo nextest run --features unix --no-fail-fast
To debug:
rust-gdb --args target/debug/coreutils ls
(gdb) b ls.rs:79
(gdb) run
To simply test all available utilities:
make test
To test all but a few of the available utilities:
make SKIP_UTILS='UTILITY_1 UTILITY_2' test
To test only a few of the available utilities:
make UTILS='UTILITY_1 UTILITY_2' test
To include tests for unimplemented behavior:
make UTILS='UTILITY_1 UTILITY_2' SPEC=y test
To run tests with nextest
just use the nextest target. Note you'll need to
install nextest
first. The nextest
target accepts the
same arguments like the default test
target, so it's possible to pass arguments to nextest run
via CARGOFLAGS
:
make CARGOFLAGS='--no-fail-fast' UTILS='UTILITY_1 UTILITY_2' nextest
This testing functionality is only available on *nix operating systems and
requires make
.
To run busybox tests for all utilities for which busybox has tests
make busytest
To run busybox tests for a few of the available utilities
make UTILS='UTILITY_1 UTILITY_2' busytest
To pass an argument like "-v" to the busybox test runtime
make UTILS='UTILITY_1 UTILITY_2' RUNTEST_ARGS='-v' busytest
To run uutils against the GNU test suite locally, run the following commands:
bash util/build-gnu.sh
# Build uutils with release optimizations
bash util/build-gnu.sh --release-build
bash util/run-gnu-test.sh
# To run a single test:
bash util/run-gnu-test.sh tests/touch/not-owner.sh # for example
# To run several tests:
bash util/run-gnu-test.sh tests/touch/not-owner.sh tests/rm/no-give-up.sh # for example
# If this is a perl (.pl) test, to run in debug:
DEBUG=1 bash util/run-gnu-test.sh tests/misc/sm3sum.pl
Tip: First time you run bash util/build-gnu.sh
command, it will provide instructions on how to checkout GNU coreutils repository at the correct release tag. Please follow those instructions and when done, run bash util/build-gnu.sh
command again.
Note that GNU test suite relies on individual utilities (not the multicall binary).
On FreeBSD, you need to install packages for GNU coreutils and sed (used in shell scripts instead of system commands):
pkg install coreutils gsed
Code coverage report can be generated using grcov.
To generate gcov-based coverage report
export CARGO_INCREMENTAL=0
export RUSTFLAGS="-Zprofile -Ccodegen-units=1 -Copt-level=0 -Clink-dead-code -Coverflow-checks=off -Zpanic_abort_tests -Cpanic=abort"
export RUSTDOCFLAGS="-Cpanic=abort"
cargo build <options...> # e.g., --features feat_os_unix
cargo test <options...> # e.g., --features feat_os_unix test_pathchk
grcov . -s . --binary-path ./target/debug/ -t html --branch --ignore-not-existing --ignore build.rs --excl-br-line "^\s*((debug_)?assert(_eq|_ne)?\#\[derive\()" -o ./target/debug/coverage/
# open target/debug/coverage/index.html in browser
if changes are not reflected in the report then run cargo clean
and run the above commands.
If you are using stable version of Rust that doesn't enable code coverage instrumentation by default
then add -Z-Zinstrument-coverage
flag to RUSTFLAGS
env variable specified above.
On MacOS you'll need to install C compiler & linker:
xcode-select --install
On MacOS you will need to install Homebrew and use it to install the following Homebrew formulas:
brew install \
coreutils \
autoconf \
gettext \
wget \
texinfo \
xz \
automake \
gnu-sed \
m4 \
bison \
pre-commit \
findutils
After installing these Homebrew formulas, please make sure to add the following lines to your zsh
or bash
rc file, i.e. ~/.profile
or ~/.zshrc
or ~/.bashrc
...
(assuming Homebrew is installed at default location /opt/homebrew
):
eval "$(/opt/homebrew/bin/brew shellenv)"
export PATH="/opt/homebrew/opt/coreutils/libexec/gnubin:$PATH"
export PATH="/opt/homebrew/opt/bison/bin:$PATH"
export PATH="/opt/homebrew/opt/findutils/libexec/gnubin:$PATH"
Last step is to link Homebrew coreutils version of timeout
to /usr/local/bin
(as admin user):
sudo ln -s /opt/homebrew/bin/timeout /usr/local/bin/timeout
Do not forget to either source updated rc file or restart you terminal session to update environment variables.
On Windows you'll need the MSVC build tools for Visual Studio 2013 or later.
If you are using rustup-init.exe
to install Rust toolchain, it will guide you through the process of downloading and installing these prerequisites.
Otherwise please follow this guide.
If you have used Git for Windows to install git
on you Windows system you might already have some GNU core utilities installed as part of "GNU Bash" included in Git for Windows package, but it is not a complete package. This article provides instruction on how to add more to it.
Alternatively you can install Cygwin and/or use WSL2 to get access to all GNU core utilities on Windows.