.envrc

bash tools/check-correct-nix-install.sh

# Enable the nix-community direnv integration
if ! has nix_direnv_version || ! nix_direnv_version 3.0.4; then
    source_url \
        "https://raw.githubusercontent.com/nix-community/nix-direnv/3.0.4/direnvrc" "sha256-DzlYZ33mWF/Gs8DDeyjr8mnVmQGx7ASYqA5WlxwvBG4="
fi

# [tag:nix-direnv-watch-nix-files] Make sure we watch all files relevant to the
# "boostrap phase" here, so that changes appropriately cause the shell to be
# reloaded. Any extra nix files situated near the Flake should be added here.
watch_file buck/nix/buck2/Cargo.lock buck/nix/buck2/default.nix
watch_file buck/nix/toolchains/default.nix
watch_file buck/nix/flake.nix buck/nix/flake.lock

# Enable the flake
use flake . --accept-flake-config

# [tag:auto-watchman] In order to help keep track of files more accurately, we
# use Watchman, and we automatically start it if it's not already running, and
# the user has allowed it. This is a bit of a hack, but it helps keep the shell
# environment clean.
if [ "$(uname)" = "Darwin" ]; then

    # FIXME: macOS support
    echo "WARNING: direnv: watchman: not enabling, because we're on macOS"

elif [ ! -f .use-watchman ] && [ -z "$CI_RUNNING" ]; then

    # FIXME: prompt about this file to the user
    echo "WARNING: direnv: watchman: not enabled, because " \
        ".use-watchman is missing, and we're not in a CI build"
else

    [ "$CI_RUNNING" = "true" ] &&
        echo "direnv: watchman: enabling, because we're running in a CI build"

    # XXX FIXME: shouldn't require systemd on Linux, but in practice
    # systemd is the only option for multi-user Nix and the only thing supported by
    # upstream, so it is what it is.
    [ ! -d /run/systemd/system ] &&
        echo "ERROR: direnv: watchman: cannot enable, because you aren't using systemd" &&
        exit 1

    export WATCHMAN_SOCK="$HOME/.local/state/watchman/.watchman-socket"
    if ! systemctl --user is-active --quiet watchman; then
        echo "direnv: watchman: no service active; starting a transient watchman.service user unit..."

        systemd-run -q --user \
            -u watchman.service \
            --working-directory="$HOME/.local/state/watchman" \
            -p StateDirectory=watchman \
            -p StandardOutput=journal \
            -p Restart=on-failure \
            watchman --foreground \
            -u "$WATCHMAN_SOCK" \
            --logfile="$HOME/.local/state/watchman/log" \
            --statefile="$HOME/.local/state/watchman/state" \
            --pidfile="$HOME/.local/state/watchman/pid"

        echo "direnv: watchman: ok, see 'systemctl --user status watchman.service' for details"
    else
        echo "direnv: watchman: service is already active, continuing..."
    fi
fi