ci.yml

name: CI
on:
  push:
    branches:
      - 'master'
    tags:
      - '*'
  pull_request:
  merge_group:
  schedule:
    - cron: '0 7 * * *'  # 8AM CET/11PM PT
  # for manual re-release of a nightly
  workflow_dispatch:
    inputs:
      action:
        description: 'Action'
        required: true
        default: 'release nightly'
        type: choice
        options:
        - release nightly


concurrency:
  group: ${{ github.workflow }}-${{ github.ref }}-${{ github.event_name }}
  cancel-in-progress: true

jobs:

  # This job determines various settings for the following CI runs; see the `outputs` for details
  configure:
    runs-on: ubuntu-latest
    outputs:
      # 0: PRs without special label
      # 1: PRs with `merge-ci` label, merge queue checks, master commits
      # 2: PRs with `release-ci` label, releases (incl. nightlies)
      check-level: ${{ steps.set-level.outputs.check-level }}
      # The build matrix, dynamically generated here
      matrix: ${{ steps.set-matrix.outputs.result }}
      # Should we make a nightly release? If so, this output contains the lean version string, else it is empty
      nightly: ${{ steps.set-nightly.outputs.nightly }}
      # Should this be the CI for a tagged release?
      # Yes only if a tag is pushed to the `leanprover` repository, and the tag is "v" followed by a valid semver.
      # It sets `set-release.outputs.RELEASE_TAG` to the tag
      # and sets `set-release.outputs.{LEAN_VERSION_MAJOR,LEAN_VERSION_MINOR,LEAN_VERSION_PATCH,LEAN_SPECIAL_VERSION_DESC}`
      # to the semver components parsed via regex.
      LEAN_VERSION_MAJOR: ${{ steps.set-release.outputs.LEAN_VERSION_MAJOR }}
      LEAN_VERSION_MINOR: ${{ steps.set-release.outputs.LEAN_VERSION_MINOR }}
      LEAN_VERSION_PATCH: ${{ steps.set-release.outputs.LEAN_VERSION_PATCH }}
      LEAN_SPECIAL_VERSION_DESC: ${{ steps.set-release.outputs.LEAN_SPECIAL_VERSION_DESC }}
      RELEASE_TAG: ${{ steps.set-release.outputs.RELEASE_TAG }}

    steps:
      - name: Checkout
        uses: actions/checkout@v4
        # don't schedule nightlies on forks
        if: github.event_name == 'schedule' && github.repository == 'leanprover/lean4' || inputs.action == 'release nightly'
      - name: Set Nightly
        if: github.event_name == 'schedule' && github.repository == 'leanprover/lean4' || inputs.action == 'release nightly'
        id: set-nightly
        run: |
          if [[ -n '${{ secrets.PUSH_NIGHTLY_TOKEN }}' ]]; then
            git remote add nightly https://foo:'${{ secrets.PUSH_NIGHTLY_TOKEN }}'@github.com/${{ github.repository_owner }}/lean4-nightly.git
            git fetch nightly --tags
            LEAN_VERSION_STRING="nightly-$(date -u +%F)"
            # do nothing if commit already has a different tag
            if [[ "$(git name-rev --name-only --tags --no-undefined HEAD 2> /dev/null || echo "$LEAN_VERSION_STRING")" == "$LEAN_VERSION_STRING" ]]; then
              echo "nightly=$LEAN_VERSION_STRING" >> "$GITHUB_OUTPUT"
            fi
          fi

      - name: Check for official release
        if: startsWith(github.ref, 'refs/tags/') && github.repository == 'leanprover/lean4'
        id: set-release
        run: |
          TAG_NAME="${GITHUB_REF##*/}"

          # From https://github.com/fsaintjacques/semver-tool/blob/master/src/semver

          NAT='0|[1-9][0-9]*'
          ALPHANUM='[0-9]*[A-Za-z-][0-9A-Za-z-]*'
          IDENT="$NAT|$ALPHANUM"
          FIELD='[0-9A-Za-z-]+'

          SEMVER_REGEX="\
          ^[vV]?\
          ($NAT)\\.($NAT)\\.($NAT)\
          (\\-(${IDENT})(\\.(${IDENT}))*)?\
          (\\+${FIELD}(\\.${FIELD})*)?$"

          if [[ ${TAG_NAME} =~ ${SEMVER_REGEX} ]]; then
            echo "Tag ${TAG_NAME} matches SemVer regex, with groups ${BASH_REMATCH[1]} ${BASH_REMATCH[2]} ${BASH_REMATCH[3]} ${BASH_REMATCH[4]}"
            {
              echo "LEAN_VERSION_MAJOR=${BASH_REMATCH[1]}"
              echo "LEAN_VERSION_MINOR=${BASH_REMATCH[2]}"
              echo "LEAN_VERSION_PATCH=${BASH_REMATCH[3]}"
              echo "LEAN_SPECIAL_VERSION_DESC=${BASH_REMATCH[4]##-}"
              echo "RELEASE_TAG=$TAG_NAME"
            } >> "$GITHUB_OUTPUT"
          else
            echo "Tag ${TAG_NAME} did not match SemVer regex."
          fi

      - name: Set check level
        id: set-level
        # We do not use github.event.pull_request.labels.*.name here because
        # re-running a run does not update that list, and we do want to be able to
        # rerun the workflow run after setting the `release-ci`/`merge-ci` labels.
        run: |
          check_level=0

          if [[ -n "${{ steps.set-nightly.outputs.nightly }}" || -n "${{ steps.set-release.outputs.RELEASE_TAG }}" ]]; then
            check_level=2
          elif [[ "${{ github.event_name }}" != "pull_request" ]]; then
            check_level=1
          else
            labels="$(gh api repos/${{ github.repository_owner }}/${{ github.event.repository.name }}/pulls/${{ github.event.pull_request.number }}) --jq '.labels'"
            if echo "$labels" | grep -q "release-ci"; then
              check_level=2
            elif echo "$labels" | grep -q "merge-ci"; then
              check_level=1
            fi
          fi

          echo "check-level=$check_level" >> "$GITHUB_OUTPUT"
        env:
          GH_TOKEN: ${{ github.token }}

      - name: Configure build matrix
        id: set-matrix
        uses: actions/github-script@v7
        with:
          script: |
            const level = ${{ steps.set-level.outputs.check-level }};
            console.log(`level: ${level}`);
            // use large runners where available (original repo)
            let large = ${{ github.repository == 'leanprover/lean4' }};
            let matrix = [
              {
                // portable release build: use channel with older glibc (2.27)
                "name": "Linux LLVM",
                "os": "ubuntu-latest",
                "release": false,
                "check-level": 2,
                "shell": "nix develop .#oldGlibc -c bash -euxo pipefail {0}",
                "llvm-url": "https://github.com/leanprover/lean-llvm/releases/download/15.0.1/lean-llvm-x86_64-linux-gnu.tar.zst",
                "prepare-llvm": "../script/prepare-llvm-linux.sh lean-llvm*",
                "binary-check": "ldd -v",
                // foreign code may be linked against more recent glibc
                // reverse-ffi needs to be updated to link to LLVM libraries
                "CTEST_OPTIONS": "-E 'foreign|leanlaketest_reverse-ffi'",
                "CMAKE_OPTIONS": "-DLLVM=ON -DLLVM_CONFIG=${GITHUB_WORKSPACE}/build/llvm-host/bin/llvm-config"
              },
              {
                "name": "Linux release",
                "os": large ? "nscloud-ubuntu-22.04-amd64-4x8" : "ubuntu-latest",
                "release": true,
                "check-level": 0,
                "shell": "nix develop .#oldGlibc -c bash -euxo pipefail {0}",
                "llvm-url": "https://github.com/leanprover/lean-llvm/releases/download/15.0.1/lean-llvm-x86_64-linux-gnu.tar.zst",
                "prepare-llvm": "../script/prepare-llvm-linux.sh lean-llvm*",
                "binary-check": "ldd -v",
                // foreign code may be linked against more recent glibc
                "CTEST_OPTIONS": "-E 'foreign'"
              },
              {
                "name": "Linux",
                "os": large ? "nscloud-ubuntu-22.04-amd64-4x8" : "ubuntu-latest",
                "check-stage3": level >= 2,
                "test-speedcenter": level >= 2,
                "check-level": 1,
              },
              {
                "name": "Linux Debug",
                "os": "ubuntu-latest",
                "check-level": 2,
                "CMAKE_PRESET": "debug",
                // exclude seriously slow tests
                "CTEST_OPTIONS": "-E 'interactivetest|leanpkgtest|laketest|benchtest'"
              },
              // TODO: suddenly started failing in CI
              /*{
                "name": "Linux fsanitize",
                "os": "ubuntu-latest",
                "check-level": 2,
                // turn off custom allocator & symbolic functions to make LSAN do its magic
                "CMAKE_PRESET": "sanitize",
                // exclude seriously slow/problematic tests (laketests crash)
                "CTEST_OPTIONS": "-E 'interactivetest|leanpkgtest|laketest|benchtest'"
              },*/
              {
                "name": "macOS",
                "os": "macos-13",
                "release": true,
                "check-level": 2,
                "shell": "bash -euxo pipefail {0}",
                "llvm-url": "https://github.com/leanprover/lean-llvm/releases/download/15.0.1/lean-llvm-x86_64-apple-darwin.tar.zst",
                "prepare-llvm": "../script/prepare-llvm-macos.sh lean-llvm*",
                "binary-check": "otool -L",
                "tar": "gtar" // https://github.com/actions/runner-images/issues/2619
              },
              {
                "name": "macOS aarch64",
                "os": "macos-14",
                "CMAKE_OPTIONS": "-DLEAN_INSTALL_SUFFIX=-darwin_aarch64",
                "release": true,
                "check-level": 1,
                "shell": "bash -euxo pipefail {0}",
                "llvm-url": "https://github.com/leanprover/lean-llvm/releases/download/15.0.1/lean-llvm-aarch64-apple-darwin.tar.zst",
                "prepare-llvm": "../script/prepare-llvm-macos.sh lean-llvm*",
                "binary-check": "otool -L",
                "tar": "gtar" // https://github.com/actions/runner-images/issues/2619
              },
              {
                "name": "Windows",
                "os": "windows-2022",
                "release": true,
                "check-level": 2,
                "shell": "msys2 {0}",
                "CMAKE_OPTIONS": "-G \"Unix Makefiles\" -DUSE_GMP=OFF",
                // for reasons unknown, interactivetests are flaky on Windows
                "CTEST_OPTIONS": "--repeat until-pass:2",
                "llvm-url": "https://github.com/leanprover/lean-llvm/releases/download/15.0.1/lean-llvm-x86_64-w64-windows-gnu.tar.zst",
                "prepare-llvm": "../script/prepare-llvm-mingw.sh lean-llvm*",
                "binary-check": "ldd"
              },
              {
                "name": "Linux aarch64",
                "os": "nscloud-ubuntu-22.04-arm64-4x8",
                "CMAKE_OPTIONS": "-DUSE_GMP=OFF -DLEAN_INSTALL_SUFFIX=-linux_aarch64",
                "release": true,
                "check-level": 2,
                "shell": "nix develop .#oldGlibcAArch -c bash -euxo pipefail {0}",
                "llvm-url": "https://github.com/leanprover/lean-llvm/releases/download/15.0.1/lean-llvm-aarch64-linux-gnu.tar.zst",
                "prepare-llvm": "../script/prepare-llvm-linux.sh lean-llvm*"
              },
              {
                "name": "Linux 32bit",
                "os": "ubuntu-latest",
                // Use 32bit on stage0 and stage1 to keep oleans compatible
                "CMAKE_OPTIONS": "-DSTAGE0_USE_GMP=OFF -DSTAGE0_LEAN_EXTRA_CXX_FLAGS='-m32' -DSTAGE0_LEANC_OPTS='-m32' -DSTAGE0_MMAP=OFF -DUSE_GMP=OFF -DLEAN_EXTRA_CXX_FLAGS='-m32' -DLEANC_OPTS='-m32' -DMMAP=OFF -DLEAN_INSTALL_SUFFIX=-linux_x86 -DCMAKE_LIBRARY_PATH=/usr/lib/i386-linux-gnu/",
                "cmultilib": true,
                "release": true,
                "check-level": 2,
                "cross": true,
                "shell": "bash -euxo pipefail {0}"
              },
              {
                "name": "Web Assembly",
                "os": "ubuntu-latest",
                // Build a native 32bit binary in stage0 and use it to compile the oleans and the wasm build
                "CMAKE_OPTIONS": "-DCMAKE_C_COMPILER_WORKS=1 -DSTAGE0_USE_GMP=OFF -DSTAGE0_LEAN_EXTRA_CXX_FLAGS='-m32' -DSTAGE0_LEANC_OPTS='-m32' -DSTAGE0_CMAKE_CXX_COMPILER=clang++ -DSTAGE0_CMAKE_C_COMPILER=clang -DSTAGE0_CMAKE_EXECUTABLE_SUFFIX=\"\" -DUSE_GMP=OFF -DMMAP=OFF -DSTAGE0_MMAP=OFF -DCMAKE_AR=../emsdk/emsdk-main/upstream/emscripten/emar -DCMAKE_TOOLCHAIN_FILE=../emsdk/emsdk-main/upstream/emscripten/cmake/Modules/Platform/Emscripten.cmake -DLEAN_INSTALL_SUFFIX=-linux_wasm32",
                "wasm": true,
                "cmultilib": true,
                "release": true,
                "check-level": 2,
                "cross": true,
                "shell": "bash -euxo pipefail {0}",
                // Just a few selected tests because wasm is slow
                "CTEST_OPTIONS": "-R \"leantest_1007\\.lean|leantest_Format\\.lean|leanruntest\\_1037.lean|leanruntest_ac_rfl\\.lean|leanruntest_libuv\\.lean\""
              }
            ];
            console.log(`matrix:\n${JSON.stringify(matrix, null, 2)}`)
            return matrix.filter((job) => level >= job["check-level"])

  build:
    needs: [configure]
    if: github.event_name != 'schedule' || github.repository == 'leanprover/lean4'
    strategy:
      matrix:
        include: ${{fromJson(needs.configure.outputs.matrix)}}
      # complete all jobs
      fail-fast: false
    runs-on: ${{ matrix.os }}
    defaults:
      run:
        shell: ${{ matrix.shell || 'nix develop -c bash -euxo pipefail {0}' }}
    name: ${{ matrix.name }}
    env:
      # must be inside workspace
      CCACHE_DIR: ${{ github.workspace }}/.ccache
      CCACHE_COMPRESS: true
      # current cache limit
      CCACHE_MAXSIZE: 200M
      # squelch error message about missing nixpkgs channel
      NIX_BUILD_SHELL: bash
      LSAN_OPTIONS: max_leaks=10
      # somehow MinGW clang64 (or cmake?) defaults to `g++` even though it doesn't exist
      CXX: c++
      MACOSX_DEPLOYMENT_TARGET: 10.15
    steps:
      - name: Install Nix
        uses: DeterminateSystems/nix-installer-action@main
        if: runner.os == 'Linux' && !matrix.cmultilib
      - name: Install MSYS2
        uses: msys2/setup-msys2@v2
        with:
          msystem: clang64
          # `:` means do not prefix with msystem
          pacboy: "make: python: cmake clang ccache gmp libuv git: zip: unzip: diffutils: binutils: tree: zstd tar:"
        if: runner.os == 'Windows'
      - name: Install Brew Packages
        run: |
          brew install ccache tree zstd coreutils gmp libuv
        if: runner.os == 'macOS'
      - name: Checkout
        uses: actions/checkout@v4
        with:
          # the default is to use a virtual merge commit between the PR and master: just use the PR
          ref: ${{ github.event.pull_request.head.sha }}
      # Do check out some CI-relevant files from virtual merge commit to accommodate CI changes on
      # master (as the workflow files themselves are always taken from the merge)
      # (needs to be after "Install *" to use the right shell)
      - name: CI Merge Checkout
        run: |
          git fetch --depth=1 origin ${{ github.sha }}
          git checkout FETCH_HEAD flake.nix flake.lock
        if: github.event_name == 'pull_request'
      # (needs to be after "Checkout" so files don't get overriden)
      - name: Setup emsdk
        uses: mymindstorm/setup-emsdk@v12
        with:
          version: 3.1.44
          actions-cache-folder: emsdk
        if: matrix.wasm
      - name: Install 32bit c libs
        run: |
          sudo dpkg --add-architecture i386
          sudo apt-get update
          sudo apt-get install -y gcc-multilib g++-multilib ccache libuv1-dev:i386
        if: matrix.cmultilib
      - name: Cache
        uses: actions/cache@v4
        with:
          path: .ccache
          key: ${{ matrix.name }}-build-v3-${{ github.event.pull_request.head.sha }}
          # fall back to (latest) previous cache
          restore-keys: |
            ${{ matrix.name }}-build-v3
          save-always: true
      # open nix-shell once for initial setup
      - name: Setup
        run: |
          ccache --zero-stats
        if: runner.os == 'Linux'
      - name: Set up NPROC
        run: |
          echo "NPROC=$(nproc 2>/dev/null || sysctl -n hw.logicalcpu 2>/dev/null || echo 4)" >> $GITHUB_ENV
      - name: Build
        run: |
          mkdir build
          cd build
          # arguments passed to `cmake`
          # this also enables githash embedding into stage 1 library
          OPTIONS=(-DCHECK_OLEAN_VERSION=ON)
          OPTIONS+=(-DLEAN_EXTRA_MAKE_OPTS=-DwarningAsError=true)
          if [[ -n '${{ matrix.cross_target }}' ]]; then
            # used by `prepare-llvm`
            export EXTRA_FLAGS=--target=${{ matrix.cross_target }}
            OPTIONS+=(-DLEAN_PLATFORM_TARGET=${{ matrix.cross_target }})
          fi
          if [[ -n '${{ matrix.prepare-llvm }}' ]]; then
            wget -q ${{ matrix.llvm-url }}
            PREPARE="$(${{ matrix.prepare-llvm }})"
            eval "OPTIONS+=($PREPARE)"
          fi
          if [[ -n '${{ matrix.release }}' && -n '${{ needs.configure.outputs.nightly }}' ]]; then
            OPTIONS+=(-DLEAN_SPECIAL_VERSION_DESC=${{ needs.configure.outputs.nightly }})
          fi
          if [[ -n '${{ matrix.release }}' && -n '${{ needs.configure.outputs.RELEASE_TAG }}' ]]; then
            OPTIONS+=(-DLEAN_VERSION_MAJOR=${{ needs.configure.outputs.LEAN_VERSION_MAJOR }})
            OPTIONS+=(-DLEAN_VERSION_MINOR=${{ needs.configure.outputs.LEAN_VERSION_MINOR }})
            OPTIONS+=(-DLEAN_VERSION_PATCH=${{ needs.configure.outputs.LEAN_VERSION_PATCH }})
            OPTIONS+=(-DLEAN_VERSION_IS_RELEASE=1)
            OPTIONS+=(-DLEAN_SPECIAL_VERSION_DESC=${{ needs.configure.outputs.LEAN_SPECIAL_VERSION_DESC }})
          fi
          # contortion to support empty OPTIONS with old macOS bash
          cmake .. --preset ${{ matrix.CMAKE_PRESET || 'release' }} -B . ${{ matrix.CMAKE_OPTIONS }} ${OPTIONS[@]+"${OPTIONS[@]}"} -DLEAN_INSTALL_PREFIX=$PWD/..
          time make -j$NPROC
      - name: Install
        run: |
          make -C build install
      - name: Check Binaries
        run: ${{ matrix.binary-check }} lean-*/bin/* || true
      - name: Count binary symbols
        run: |
          for f in lean-*/bin/*; do
            echo "$f: $(nm $f | grep " T " | wc -l) exported symbols"
          done
        if: matrix.name == 'Windows'
      - name: List Install Tree
        run: |
          # omit contents of Init/, ...
          tree --du -h lean-*-* | grep -E ' (Init|Lean|Lake|LICENSE|[a-z])'
      - name: Pack
        run: |
          dir=$(echo lean-*-*)
          mkdir pack
          # high-compression tar.zst + zip for release, fast tar.zst otherwise
          if [[ '${{ startsWith(github.ref, 'refs/tags/') && matrix.release }}' == true || -n '${{ needs.configure.outputs.nightly }}' || -n '${{ needs.configure.outputs.RELEASE_TAG }}' ]]; then
            ${{ matrix.tar || 'tar' }} cf - $dir | zstd -T0 --no-progress -19 -o pack/$dir.tar.zst
            zip -rq pack/$dir.zip $dir
          else
            ${{ matrix.tar || 'tar' }} cf - $dir | zstd -T0 --no-progress -o pack/$dir.tar.zst
          fi
      - uses: actions/upload-artifact@v4
        if: matrix.release
        with:
          name: build-${{ matrix.name }}
          path: pack/*
      - name: Lean stats
        run: |
          build/stage1/bin/lean --stats src/Lean.lean
        if: ${{ !matrix.cross }}
      - name: Test
        id: test
        run: |
          time ctest --preset ${{ matrix.CMAKE_PRESET || 'release' }} --test-dir build/stage1 -j$NPROC --output-junit test-results.xml ${{ matrix.CTEST_OPTIONS }}
        if: (matrix.wasm || !matrix.cross) && needs.configure.outputs.check-level >= 1
      - name: Test Summary
        uses: test-summary/action@v2
        with:
          paths: build/stage1/test-results.xml
        # prefix `if` above with `always` so it's run even if tests failed
        if: always() && steps.test.conclusion != 'skipped'
      - name: Check Test Binary
        run: ${{ matrix.binary-check }} tests/compiler/534.lean.out
        if: (!matrix.cross) && steps.test.conclusion != 'skipped'
      - name: Build Stage 2
        run: |
          make -C build -j$NPROC stage2
        if: matrix.test-speedcenter
      - name: Check Stage 3
        run: |
          make -C build -j$NPROC check-stage3
        if: matrix.test-speedcenter
      - name: Test Speedcenter Benchmarks
        run: |
          # Necessary for some timing metrics but does not work on Namespace runners
          # and we just want to test that the benchmarks run at all here
          #echo -1 | sudo tee /proc/sys/kernel/perf_event_paranoid
          export BUILD=$PWD/build PATH=$PWD/build/stage1/bin:$PATH
          cd tests/bench
          nix shell .#temci -c temci exec --config speedcenter.yaml --included_blocks fast --runs 1
        if: matrix.test-speedcenter
      - name: Check rebootstrap
        run: |
          # clean rebuild in case of Makefile changes
          make -C build update-stage0 && rm -rf build/stage* && make -C build -j$NPROC
        if: matrix.name == 'Linux' && needs.configure.outputs.check-level >= 1
      - name: CCache stats
        run: ccache -s

  # This job collects results from all the matrix jobs
  # This can be made the “required” job, instead of listing each
  # matrix job separately
  all-done:
    name: Build matrix complete
    runs-on: ubuntu-latest
    needs: build
    # mark as merely cancelled not failed if builds are cancelled
    if: ${{ !cancelled() }}
    steps:
    - if: ${{ contains(needs.*.result, 'failure') && github.repository == 'leanprover/lean4' && github.ref_name == 'master' }}
      uses: zulip/github-actions-zulip/send-message@v1
      with:
        api-key: ${{ secrets.ZULIP_BOT_KEY }}
        email: "github-actions-bot@lean-fro.zulipchat.com"
        organization-url: "https://lean-fro.zulipchat.com"
        to: "infrastructure"
        topic: "Github actions"
        type: "stream"
        content: |
          A build of `${{ github.ref_name }}`, triggered by event `${{ github.event_name }}`, [failed](https://github.com/${{ github.repository }}/actions/runs/${{ github.run_id }}).
    - if: contains(needs.*.result, 'failure')
      uses: actions/github-script@v7
      with:
        script: |
            core.setFailed('Some jobs failed')


  # This job creates releases from tags
  # (whether they are "unofficial" releases for experiments, or official releases when the tag is "v" followed by a semver string.)
  # We do not attempt to automatically construct a changelog here:
  # unofficial releases don't need them, and official release notes will be written by a human.
  release:
    if: startsWith(github.ref, 'refs/tags/')
    runs-on: ubuntu-latest
    needs: build
    steps:
      - uses: actions/download-artifact@v4
        with:
          path: artifacts
      - name: Release
        uses: softprops/action-gh-release@v1
        with:
          files: artifacts/*/*
          fail_on_unmatched_files: true
          prerelease: ${{ !startsWith(github.ref, 'refs/tags/v') || contains(github.ref, '-rc') }}
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
      - name: Update release.lean-lang.org
        run: |
          gh workflow -R leanprover/release-index run update-index.yml
        env:
          GITHUB_TOKEN: ${{ secrets.RELEASE_INDEX_TOKEN }}

  # This job creates nightly releases during the cron job.
  # It is responsible for creating the tag, and automatically generating a changelog.
  release-nightly:
    needs: [configure, build]
    if: needs.configure.outputs.nightly
    runs-on: ubuntu-latest
    steps:
      - name: Checkout
        uses: actions/checkout@v4
        with:
          # needed for tagging
          fetch-depth: 0
          token: ${{ secrets.PUSH_NIGHTLY_TOKEN }}
      - uses: actions/download-artifact@v4
        with:
          path: artifacts
      - name: Prepare Nightly Release
        run: |
          git remote add nightly https://foo:'${{ secrets.PUSH_NIGHTLY_TOKEN }}'@github.com/${{ github.repository_owner }}/lean4-nightly.git
          git fetch nightly --tags
          git tag "${{ needs.configure.outputs.nightly }}"
          git push nightly "${{ needs.configure.outputs.nightly }}"
          git push -f origin refs/tags/${{ needs.configure.outputs.nightly }}:refs/heads/nightly
          last_tag="$(git log HEAD^ --simplify-by-decoration --pretty="format:%d" | grep -o "nightly-[-0-9]*" | head -n 1)"
          echo -e "*Changes since ${last_tag}:*\n\n" > diff.md
          git show "$last_tag":RELEASES.md > old.md
          #./script/diff_changelogs.py old.md doc/changes.md >> diff.md
          diff --changed-group-format='%>' --unchanged-group-format='' old.md RELEASES.md >> diff.md || true
          echo -e "\n*Full commit log*\n" >> diff.md
          git log --oneline "$last_tag"..HEAD | sed 's/^/* /' >> diff.md
      - name: Release Nightly
        uses: softprops/action-gh-release@v1
        with:
          body_path: diff.md
          prerelease: true
          files: artifacts/*/*
          fail_on_unmatched_files: true
          tag_name: ${{ needs.configure.outputs.nightly }}
          repository: ${{ github.repository_owner }}/lean4-nightly
        env:
          GITHUB_TOKEN: ${{ secrets.PUSH_NIGHTLY_TOKEN }}
      - name: Update release.lean-lang.org
        run: |
          gh workflow -R leanprover/release-index run update-index.yml
        env:
          GITHUB_TOKEN: ${{ secrets.RELEASE_INDEX_TOKEN }}
      - name: Update toolchain on mathlib4's nightly-testing branch
        run: |
          gh workflow -R leanprover-community/mathlib4 run nightly_bump_toolchain.yml
        env:
          GITHUB_TOKEN: ${{ secrets.MATHLIB4_BOT }}