My `x.py` for rustc development

x.sh

#!/usr/bin/env bash
# Wrapper around `x.py`. Assumes it's being run from the root of the rustc repo.
RUSTC_REPO="$(realpath "$PWD")"
RUSTC_PERF_REPO="$RUSTC_REPO/../rustc-perf"

X_PY="$RUSTC_REPO/x.py"
RUSTC="$RUSTC_REPO/build/x86_64-unknown-linux-gnu/stage1/bin/rustc"
RUSTFMT="$RUSTC_REPO/build/x86_64-unknown-linux-gnu/stage0/bin/rustfmt"

cd $RUSTC_REPO || exit

case $1 in
    fmt)
        if [ "$#" -eq 1 ] && [ "$1" -eq '-u' ]; then
            $RUSTFMT compiler/rustc_mir_build/src/thir/pattern/*.rs
        else
            $X_PY fmt
        fi
    ;;
    tidy)
        $X_PY test tidy --bless
    ;;
    check)
        $X_PY check
    ;;
    check-cat)
        $X_PY check 2>&1 | cat
    ;;
    build)
        $X_PY build --stage 1
    ;;
    perf)
        shift
        # Benchmark local rustc build. This assumes it's run from the root of the rustc
        # repo, and that the rustc-perf repo is at `../rustc-perf` and has been built.
        # This compares perf relative to the `base` commit, which is a branch I move
        # around for this purpose. This stores the list of commits encountered in
        # `../rustc-perf/commits`.
        run_site=0
        test_args=('test' 'src/test/ui' '--test-args' 'pattern')
        for i in "$@"; do
            case $i in
            -s|--run-site)
                run_site=1
            ;;
            -k|--keep)
                test_args+=('--keep-stage' '1')
            ;;
            *)
                echo "Unknown option: $i" >&2
                exit 1
            ;;
            esac
        done

        $X_PY "${test_args[@]}" || exit

        BASE=base
        BASE_HASH="$(git show "$BASE" -s --format="%h")"
        COMMIT_HASH="$(git show -s --format="%h")"
        COMMIT_MSG="$(git show -s --format="%s")"
        COUNT_SINCE_BASE="$(git rev-list --count $BASE..HEAD)"
        DIRTY="$(git diff-index --quiet HEAD -- compiler || date +"-dirty-%m%dT%H%M%S")"

        BASE_NAME="b0-$BASE_HASH"
        NAME="b$COUNT_SINCE_BASE-$COMMIT_HASH$DIRTY"

        cd $RUSTC_PERF_REPO || exit
        $RUSTC_PERF_REPO/target/release/collector bench_local \
            --builds Check \
            --runs Full \
            --include unicode_normalization,match-stress-enum,encoding,match-stress-exhaustive_patterns \
            $RUSTC \
            "$NAME"

        echo
        echo "Measured $NAME" >&2
        echo "$NAME $COMMIT_MSG" >> $RUSTC_PERF_REPO/commits
        xdg-open "http://localhost:2346/compare.html?start=${BASE_NAME}&end=${NAME}&stat=instructions:u"

        if [[ "$run_site" == "1" ]]; then
            $RUSTC_PERF_REPO/target/release/site
        fi
    ;;
    test)
        shift
        args=('test' '--bless' 'src/test/ui')
        case $1 in
            -k|--keep)
                shift
                args+=('--keep-stage' '1')
            ;;
        esac
        if [ "$#" -eq 1 ]; then
            args+=('--test-args' "$1")
            shift
        fi
        echo $X_PY "${args[@]}" "$@"
        $X_PY "${args[@]}" "$@"
    ;;
    *)
        $X_PY "$@"
    ;;
esac