test.yml

name: test
on: [push, pull_request]

defaults:
  run:
    shell: bash -euv -o pipefail {0}

env:
  CFLAGS: -Werror
  MAKEFLAGS: -j
  TESTFLAGS: -k
  BENCHFLAGS:

jobs:
  # run tests
  test:
    runs-on: ubuntu-latest
    strategy:
      fail-fast: false
      matrix:
        arch: [x86_64, thumb, mips, powerpc]

    steps:
      - uses: actions/checkout@v2
      - name: install
        run: |
          # need a few things
          sudo apt-get update -qq
          sudo apt-get install -qq gcc python3 python3-pip
          pip3 install toml
          gcc --version
          python3 --version

      # cross-compile with ARM Thumb (32-bit, little-endian)
      - name: install-thumb
        if: ${{matrix.arch == 'thumb'}}
        run: |
          sudo apt-get install -qq \
            gcc-arm-linux-gnueabi \
            libc6-dev-armel-cross \
            qemu-user
          echo "CC=arm-linux-gnueabi-gcc -mthumb --static" >> $GITHUB_ENV
          echo "EXEC=qemu-arm" >> $GITHUB_ENV
          arm-linux-gnueabi-gcc --version
          qemu-arm -version
      # cross-compile with MIPS (32-bit, big-endian)
      - name: install-mips
        if: ${{matrix.arch == 'mips'}}
        run: |
          sudo apt-get install -qq \
            gcc-mips-linux-gnu \
            libc6-dev-mips-cross \
            qemu-user
          echo "CC=mips-linux-gnu-gcc --static" >> $GITHUB_ENV
          echo "EXEC=qemu-mips" >> $GITHUB_ENV
          mips-linux-gnu-gcc --version
          qemu-mips -version
      # cross-compile with PowerPC (32-bit, big-endian)
      - name: install-powerpc
        if: ${{matrix.arch == 'powerpc'}}
        run: |
          sudo apt-get install -qq \
            gcc-powerpc-linux-gnu \
            libc6-dev-powerpc-cross \
            qemu-user
          echo "CC=powerpc-linux-gnu-gcc --static" >> $GITHUB_ENV
          echo "EXEC=qemu-ppc" >> $GITHUB_ENV
          powerpc-linux-gnu-gcc --version
          qemu-ppc -version

      # does littlefs compile?
      - name: test-build
        run: |
          make clean
          make build

      # make sure example can at least compile
      - name: test-example
        run: |
          make clean
          sed -n '/``` c/,/```/{/```/d; p}' README.md > test.c
          CFLAGS="$CFLAGS \
            -Duser_provided_block_device_read=NULL \
            -Duser_provided_block_device_prog=NULL \
            -Duser_provided_block_device_erase=NULL \
            -Duser_provided_block_device_sync=NULL \
            -include stdio.h" \
            make all
          rm test.c

      # run the tests!
      - name: test
        run: |
          make clean
          make test

      # collect coverage info
      #
      # Note the goal is to maximize coverage in the small, easy-to-run
      # tests, so we intentionally exclude more aggressive powerloss testing
      # from coverage results
      - name: cov
        if: ${{matrix.arch == 'x86_64'}}
        run: |
          make lfs.cov.csv
          ./scripts/cov.py -u lfs.cov.csv
          mkdir -p cov
          cp lfs.cov.csv cov/cov.csv

      # find compile-time measurements
      - name: sizes
        run: |
          make clean
          CFLAGS="$CFLAGS \
            -DLFS_NO_ASSERT \
            -DLFS_NO_DEBUG \
            -DLFS_NO_WARN \
            -DLFS_NO_ERROR" \
            make lfs.code.csv lfs.data.csv lfs.stack.csv lfs.structs.csv
          ./scripts/structs.py -u lfs.structs.csv
          ./scripts/summary.py lfs.code.csv lfs.data.csv lfs.stack.csv \
            -bfunction \
            -fcode=code_size \
            -fdata=data_size \
            -fstack=stack_limit --max=stack_limit
          mkdir -p sizes
          cp lfs.code.csv sizes/${{matrix.arch}}.code.csv
          cp lfs.data.csv sizes/${{matrix.arch}}.data.csv
          cp lfs.stack.csv sizes/${{matrix.arch}}.stack.csv
          cp lfs.structs.csv sizes/${{matrix.arch}}.structs.csv
      - name: sizes-readonly
        run: |
          make clean
          CFLAGS="$CFLAGS \
            -DLFS_NO_ASSERT \
            -DLFS_NO_DEBUG \
            -DLFS_NO_WARN \
            -DLFS_NO_ERROR \
            -DLFS_READONLY" \
            make lfs.code.csv lfs.data.csv lfs.stack.csv lfs.structs.csv
          ./scripts/structs.py -u lfs.structs.csv
          ./scripts/summary.py lfs.code.csv lfs.data.csv lfs.stack.csv \
            -bfunction \
            -fcode=code_size \
            -fdata=data_size \
            -fstack=stack_limit --max=stack_limit
          mkdir -p sizes
          cp lfs.code.csv sizes/${{matrix.arch}}-readonly.code.csv
          cp lfs.data.csv sizes/${{matrix.arch}}-readonly.data.csv
          cp lfs.stack.csv sizes/${{matrix.arch}}-readonly.stack.csv
          cp lfs.structs.csv sizes/${{matrix.arch}}-readonly.structs.csv
      - name: sizes-threadsafe
        run: |
          make clean
          CFLAGS="$CFLAGS \
            -DLFS_NO_ASSERT \
            -DLFS_NO_DEBUG \
            -DLFS_NO_WARN \
            -DLFS_NO_ERROR \
            -DLFS_THREADSAFE" \
            make lfs.code.csv lfs.data.csv lfs.stack.csv lfs.structs.csv
          ./scripts/structs.py -u lfs.structs.csv
          ./scripts/summary.py lfs.code.csv lfs.data.csv lfs.stack.csv \
            -bfunction \
            -fcode=code_size \
            -fdata=data_size \
            -fstack=stack_limit --max=stack_limit
          mkdir -p sizes
          cp lfs.code.csv sizes/${{matrix.arch}}-threadsafe.code.csv
          cp lfs.data.csv sizes/${{matrix.arch}}-threadsafe.data.csv
          cp lfs.stack.csv sizes/${{matrix.arch}}-threadsafe.stack.csv
          cp lfs.structs.csv sizes/${{matrix.arch}}-threadsafe.structs.csv
      - name: sizes-multiversion
        run: |
          make clean
          CFLAGS="$CFLAGS \
            -DLFS_NO_ASSERT \
            -DLFS_NO_DEBUG \
            -DLFS_NO_WARN \
            -DLFS_NO_ERROR \
            -DLFS_MULTIVERSION" \
            make lfs.code.csv lfs.data.csv lfs.stack.csv lfs.structs.csv
          ./scripts/structs.py -u lfs.structs.csv
          ./scripts/summary.py lfs.code.csv lfs.data.csv lfs.stack.csv \
            -bfunction \
            -fcode=code_size \
            -fdata=data_size \
            -fstack=stack_limit --max=stack_limit
          mkdir -p sizes
          cp lfs.code.csv sizes/${{matrix.arch}}-multiversion.code.csv
          cp lfs.data.csv sizes/${{matrix.arch}}-multiversion.data.csv
          cp lfs.stack.csv sizes/${{matrix.arch}}-multiversion.stack.csv
          cp lfs.structs.csv sizes/${{matrix.arch}}-multiversion.structs.csv
      - name: sizes-migrate
        run: |
          make clean
          CFLAGS="$CFLAGS \
            -DLFS_NO_ASSERT \
            -DLFS_NO_DEBUG \
            -DLFS_NO_WARN \
            -DLFS_NO_ERROR \
            -DLFS_MIGRATE" \
            make lfs.code.csv lfs.data.csv lfs.stack.csv lfs.structs.csv
          ./scripts/structs.py -u lfs.structs.csv
          ./scripts/summary.py lfs.code.csv lfs.data.csv lfs.stack.csv \
            -bfunction \
            -fcode=code_size \
            -fdata=data_size \
            -fstack=stack_limit --max=stack_limit
          mkdir -p sizes
          cp lfs.code.csv sizes/${{matrix.arch}}-migrate.code.csv
          cp lfs.data.csv sizes/${{matrix.arch}}-migrate.data.csv
          cp lfs.stack.csv sizes/${{matrix.arch}}-migrate.stack.csv
          cp lfs.structs.csv sizes/${{matrix.arch}}-migrate.structs.csv
      - name: sizes-error-asserts
        run: |
          make clean
          CFLAGS="$CFLAGS \
            -DLFS_NO_DEBUG \
            -DLFS_NO_WARN \
            -DLFS_NO_ERROR \
            -D'LFS_ASSERT(test)=do {if(!(test)) {return -1;}} while(0)'" \
            make lfs.code.csv lfs.data.csv lfs.stack.csv lfs.structs.csv
          ./scripts/structs.py -u lfs.structs.csv
          ./scripts/summary.py lfs.code.csv lfs.data.csv lfs.stack.csv \
            -bfunction \
            -fcode=code_size \
            -fdata=data_size \
            -fstack=stack_limit --max=stack_limit
          mkdir -p sizes
          cp lfs.code.csv sizes/${{matrix.arch}}-error-asserts.code.csv
          cp lfs.data.csv sizes/${{matrix.arch}}-error-asserts.data.csv
          cp lfs.stack.csv sizes/${{matrix.arch}}-error-asserts.stack.csv
          cp lfs.structs.csv sizes/${{matrix.arch}}-error-asserts.structs.csv

      # create size statuses
      - name: upload-sizes
        uses: actions/upload-artifact@v2
        with:
          name: sizes
          path: sizes
      - name: status-sizes
        run: |
          mkdir -p status
          for f in $(shopt -s nullglob ; echo sizes/*.csv)
          do
            # skip .data.csv as it should always be zero
            [[ $f == *.data.csv ]] && continue
            export STEP="sizes$(echo $f \
              | sed -n 's/[^-.]*-\([^.]*\)\..*csv/-\1/p')"
            export CONTEXT="sizes (${{matrix.arch}}$(echo $f \
              | sed -n 's/[^-.]*-\([^.]*\)\..*csv/, \1/p')) / $(echo $f \
              | sed -n 's/[^.]*\.\(.*\)\.csv/\1/p')"
            export PREV="$(curl -sS \
              "$GITHUB_API_URL/repos/$GITHUB_REPOSITORY/status/master`
                `?per_page=100" \
              | jq -re 'select(.sha != env.GITHUB_SHA) | .statuses[]
                | select(.context == env.CONTEXT).description
                | capture("(?<prev>[0-9∞]+)").prev' \
              || echo 0)"
            export DESCRIPTION="$(./scripts/summary.py $f --max=stack_limit -Y \
              | awk '
                NR==2 {$1=0; printf "%s B",$NF}
                NR==2 && ENVIRON["PREV"]+0 != 0 {
                  printf " (%+.1f%%)",100*($NF-ENVIRON["PREV"])/ENVIRON["PREV"]
                }')"
            jq -n '{
              state: "success",
              context: env.CONTEXT,
              description: env.DESCRIPTION,
              target_job: "${{github.job}} (${{matrix.arch}})",
              target_step: env.STEP,
            }' | tee status/$(basename $f .csv).json
          done
      - name: upload-status-sizes
        uses: actions/upload-artifact@v2
        with:
          name: status
          path: status
          retention-days: 1

      # create cov statuses
      - name: upload-cov
        if: ${{matrix.arch == 'x86_64'}}
        uses: actions/upload-artifact@v2
        with:
          name: cov
          path: cov
      - name: status-cov
        if: ${{matrix.arch == 'x86_64'}}
        run: |
          mkdir -p status
          f=cov/cov.csv
          for s in lines branches
          do
            export STEP="cov"
            export CONTEXT="cov / $s"
            export PREV="$(curl -sS \
              "$GITHUB_API_URL/repos/$GITHUB_REPOSITORY/status/master`
                `?per_page=100" \
              | jq -re 'select(.sha != env.GITHUB_SHA) | .statuses[]
                | select(.context == env.CONTEXT).description
                | capture("(?<prev_a>[0-9]+)/(?<prev_b>[0-9]+)")
                | 100*((.prev_a|tonumber) / (.prev_b|tonumber))' \
              || echo 0)"
            export DESCRIPTION="$(./scripts/cov.py -u $f -f$s -Y \
              | awk -F '[ /%]+' -v s=$s '
                NR==2 {$1=0; printf "%d/%d %s",$2,$3,s}
                NR==2 && ENVIRON["PREV"]+0 != 0 {
                  printf " (%+.1f%%)",$4-ENVIRON["PREV"]
                }')"
            jq -n '{
              state: "success",
              context: env.CONTEXT,
              description: env.DESCRIPTION,
              target_job: "${{github.job}} (${{matrix.arch}})",
              target_step: env.STEP,
            }' | tee status/$(basename $f .csv)-$s.json
          done
      - name: upload-status-sizes
        if: ${{matrix.arch == 'x86_64'}}
        uses: actions/upload-artifact@v2
        with:
          name: status
          path: status
          retention-days: 1

  # run as many exhaustive tests as fits in GitHub's time limits
  #
  # this grows exponentially, so it doesn't turn out to be that many
  test-pls:
    runs-on: ubuntu-latest
    strategy:
      fail-fast: false
      matrix:
        pls: [1, 2]

    steps:
      - uses: actions/checkout@v2
      - name: install
        run: |
          # need a few things
          sudo apt-get update -qq
          sudo apt-get install -qq gcc python3 python3-pip
          pip3 install toml
          gcc --version
          python3 --version
      - name: test-pls
        if: ${{matrix.pls <= 1}}
        run: |
          TESTFLAGS="$TESTFLAGS -P${{matrix.pls}}" make test
      # >=2pls takes multiple days to run fully, so we can only
      # run a subset of tests, these are the most important
      - name: test-limited-pls
        if: ${{matrix.pls > 1}}
        run: |
          TESTFLAGS="$TESTFLAGS -P${{matrix.pls}} test_dirs test_relocations" \
            make test

  # run with LFS_NO_INTRINSICS to make sure that works
  test-no-intrinsics:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - name: install
        run: |
          # need a few things
          sudo apt-get update -qq
          sudo apt-get install -qq gcc python3 python3-pip
          pip3 install toml
          gcc --version
          python3 --version
      - name: test-no-intrinsics
        run: |
          CFLAGS="$CFLAGS -DLFS_NO_INTRINSICS" make test

  # run LFS_MULTIVERSION tests
  test-multiversion:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - name: install
        run: |
          # need a few things
          sudo apt-get update -qq
          sudo apt-get install -qq gcc python3 python3-pip
          pip3 install toml
          gcc --version
          python3 --version
      - name: test-multiversion
        run: |
          CFLAGS="$CFLAGS -DLFS_MULTIVERSION" make test

  # run tests on the older version lfs2.0
  test-lfs2_0:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - name: install
        run: |
          # need a few things
          sudo apt-get update -qq
          sudo apt-get install -qq gcc python3 python3-pip
          pip3 install toml
          gcc --version
          python3 --version
      - name: test-lfs2_0
        run: |
          CFLAGS="$CFLAGS -DLFS_MULTIVERSION" \
          TESTFLAGS="$TESTFLAGS -DDISK_VERSION=0x00020000" \
            make test

  # run under Valgrind to check for memory errors
  test-valgrind:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - name: install
        run: |
          # need a few things
          sudo apt-get update -qq
          sudo apt-get install -qq gcc python3 python3-pip valgrind
          pip3 install toml
          gcc --version
          python3 --version
          valgrind --version
      # Valgrind takes a while with diminishing value, so only test
      # on one geometry
      - name: test-valgrind
        run: |
          TESTFLAGS="$TESTFLAGS --valgrind --context=1024 -Gdefault -Pnone" \
            make test

  # test that compilation is warning free under clang
  # run with Clang, mostly to check for Clang-specific warnings
  test-clang:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - name: install
        run: |
          # need a few things
          sudo apt-get install -qq clang python3 python3-pip
          pip3 install toml
          clang --version
          python3 --version
      - name: test-clang
        run: |
          # override CFLAGS since Clang does not support -fcallgraph-info
          # and -ftrack-macro-expansions
          make \
            CC=clang \
            CFLAGS="$CFLAGS -MMD -g3 -I. -std=c99 -Wall -Wextra -pedantic" \
            test

  # run benchmarks
  #
  # note there's no real benefit to running these on multiple archs
  bench:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - name: install
        run: |
          # need a few things
          sudo apt-get update -qq
          sudo apt-get install -qq gcc python3 python3-pip valgrind
          pip3 install toml
          gcc --version
          python3 --version
          valgrind --version
      - name: bench
        run: |
          make bench

          # find bench results
          make lfs.bench.csv
          ./scripts/summary.py lfs.bench.csv \
            -bsuite \
            -freaded=bench_readed \
            -fproged=bench_proged \
            -ferased=bench_erased
          mkdir -p bench
          cp lfs.bench.csv bench/bench.csv

          # find perfbd results
          make lfs.perfbd.csv
          ./scripts/perfbd.py -u lfs.perfbd.csv
          mkdir -p bench
          cp lfs.perfbd.csv bench/perfbd.csv

      # create bench statuses
      - name: upload-bench
        uses: actions/upload-artifact@v2
        with:
          name: bench
          path: bench
      - name: status-bench
        run: |
          mkdir -p status
          f=bench/bench.csv
          for s in readed proged erased
          do
            export STEP="bench"
            export CONTEXT="bench / $s"
            export PREV="$(curl -sS \
              "$GITHUB_API_URL/repos/$GITHUB_REPOSITORY/status/master`
                `?per_page=100" \
              | jq -re 'select(.sha != env.GITHUB_SHA) | .statuses[]
                | select(.context == env.CONTEXT).description
                | capture("(?<prev>[0-9]+)").prev' \
              || echo 0)"
            export DESCRIPTION="$(./scripts/summary.py $f -f$s=bench_$s -Y \
              | awk '
                NR==2 {$1=0; printf "%s B",$NF}
                NR==2 && ENVIRON["PREV"]+0 != 0 {
                  printf " (%+.1f%%)",100*($NF-ENVIRON["PREV"])/ENVIRON["PREV"]
                }')"
            jq -n '{
              state: "success",
              context: env.CONTEXT,
              description: env.DESCRIPTION,
              target_job: "${{github.job}}",
              target_step: env.STEP,
            }' | tee status/$(basename $f .csv)-$s.json
          done
      - name: upload-status-bench
        uses: actions/upload-artifact@v2
        with:
          name: status
          path: status
          retention-days: 1

  # run compatibility tests using the current master as the previous version
  test-compat:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
        if: ${{github.event_name == 'pull_request'}}
      # checkout the current pr target into lfsp
      - uses: actions/checkout@v2
        if: ${{github.event_name == 'pull_request'}}
        with:
          ref: ${{github.event.pull_request.base.ref}}
          path: lfsp
      - name: install
        if: ${{github.event_name == 'pull_request'}}
        run: |
          # need a few things
          sudo apt-get update -qq
          sudo apt-get install -qq gcc python3 python3-pip
          pip3 install toml
          gcc --version
          python3 --version
      # adjust prefix of lfsp
      - name: changeprefix
        if: ${{github.event_name == 'pull_request'}}
        run: |
          ./scripts/changeprefix.py lfs lfsp lfsp/*.h lfsp/*.c
      - name: test-compat
        if: ${{github.event_name == 'pull_request'}}
        run: |
          TESTS=tests/test_compat.toml \
            SRC="$(find . lfsp -name '*.c' -maxdepth 1 \
                -and -not -name '*.t.*' \
                -and -not -name '*.b.*')" \
            CFLAGS="-DLFSP=lfsp/lfsp.h" \
            make test

  # self-host with littlefs-fuse for a fuzz-like test
  fuse:
    runs-on: ubuntu-latest
    if: ${{!endsWith(github.ref, '-prefix')}}
    steps:
      - uses: actions/checkout@v2
      - name: install
        run: |
          # need a few things
          sudo apt-get update -qq
          sudo apt-get install -qq gcc python3 python3-pip libfuse-dev
          sudo pip3 install toml
          gcc --version
          python3 --version
          fusermount -V
      - uses: actions/checkout@v2
        with:
          repository: littlefs-project/littlefs-fuse
          ref: v2
          path: littlefs-fuse
      - name: setup
        run: |
          # copy our new version into littlefs-fuse
          rm -rf littlefs-fuse/littlefs/*
          cp -r $(git ls-tree --name-only HEAD) littlefs-fuse/littlefs

          # setup disk for littlefs-fuse
          mkdir mount
          LOOP=$(sudo losetup -f)
          sudo chmod a+rw $LOOP
          dd if=/dev/zero bs=512 count=128K of=disk
          losetup $LOOP disk
          echo "LOOP=$LOOP" >> $GITHUB_ENV
      - name: test
        run: |
          # self-host test
          make -C littlefs-fuse

          littlefs-fuse/lfs --format $LOOP
          littlefs-fuse/lfs $LOOP mount

          ls mount
          mkdir mount/littlefs
          cp -r $(git ls-tree --name-only HEAD) mount/littlefs
          cd mount/littlefs
          stat .
          ls -flh
          make -B test-runner
          make -B test

  # test migration using littlefs-fuse
  migrate:
    runs-on: ubuntu-latest
    if: ${{!endsWith(github.ref, '-prefix')}}
    steps:
      - uses: actions/checkout@v2
      - name: install
        run: |
          # need a few things
          sudo apt-get update -qq
          sudo apt-get install -qq gcc python3 python3-pip libfuse-dev
          sudo pip3 install toml
          gcc --version
          python3 --version
          fusermount -V
      - uses: actions/checkout@v2
        with:
          repository: littlefs-project/littlefs-fuse
          ref: v2
          path: v2
      - uses: actions/checkout@v2
        with:
          repository: littlefs-project/littlefs-fuse
          ref: v1
          path: v1
      - name: setup
        run: |
          # copy our new version into littlefs-fuse
          rm -rf v2/littlefs/*
          cp -r $(git ls-tree --name-only HEAD) v2/littlefs

          # setup disk for littlefs-fuse
          mkdir mount
          LOOP=$(sudo losetup -f)
          sudo chmod a+rw $LOOP
          dd if=/dev/zero bs=512 count=128K of=disk
          losetup $LOOP disk
          echo "LOOP=$LOOP" >> $GITHUB_ENV
      - name: test
        run: |
          # compile v1 and v2
          make -C v1
          make -C v2

          # run self-host test with v1
          v1/lfs --format $LOOP
          v1/lfs $LOOP mount

          ls mount
          mkdir mount/littlefs
          cp -r $(git ls-tree --name-only HEAD) mount/littlefs
          cd mount/littlefs
          stat .
          ls -flh
          make -B test-runner
          make -B test

          # attempt to migrate
          cd ../..
          fusermount -u mount

          v2/lfs --migrate $LOOP
          v2/lfs $LOOP mount

          # run self-host test with v2 right where we left off
          ls mount
          cd mount/littlefs
          stat .
          ls -flh
          make -B test-runner
          make -B test

  # status related tasks that run after tests
  status:
    runs-on: ubuntu-latest
    needs: [test, bench]
    steps:
      - uses: actions/checkout@v2
        if: ${{github.event_name == 'pull_request'}}
      - name: install
        if: ${{github.event_name == 'pull_request'}}
        run: |
          # need a few things
          sudo apt-get install -qq gcc python3 python3-pip
          pip3 install toml
          gcc --version
          python3 --version
      - uses: actions/download-artifact@v2
        if: ${{github.event_name == 'pull_request'}}
        continue-on-error: true
        with:
          name: sizes
          path: sizes
      - uses: actions/download-artifact@v2
        if: ${{github.event_name == 'pull_request'}}
        continue-on-error: true
        with:
          name: cov
          path: cov
      - uses: actions/download-artifact@v2
        if: ${{github.event_name == 'pull_request'}}
        continue-on-error: true
        with:
          name: bench
          path: bench

      # try to find results from tests
      - name: create-table
        if: ${{github.event_name == 'pull_request'}}
        run: |
          # compare against pull-request target
          curl -sS \
            "$GITHUB_API_URL/repos/$GITHUB_REPOSITORY/status/`
              `${{github.event.pull_request.base.ref}}`
              `?per_page=100" \
            | jq -re 'select(.sha != env.GITHUB_SHA) | .statuses[]' \
            >> prev-status.json \
            || true

          # build table for GitHub
          declare -A table

          # sizes table
          i=0
          j=0
          for c in "" readonly threadsafe multiversion migrate error-asserts
          do
            # per-config results
            c_or_default=${c:-default}
            c_camel=${c_or_default^}
            table[$i,$j]=$c_camel
            ((j+=1))

            for s in code stack structs
            do
              f=sizes/thumb${c:+-$c}.$s.csv
              [ -e $f ] && table[$i,$j]=$( \
                export PREV="$(jq -re '
                    select(.context == "'"sizes (thumb${c:+, $c}) / $s"'").description
                    | capture("(?<prev>[0-9∞]+)").prev' \
                  prev-status.json || echo 0)"
                ./scripts/summary.py $f --max=stack_limit -Y \
                  | awk '
                    NR==2 {$1=0; printf "%s B",$NF}
                    NR==2 && ENVIRON["PREV"]+0 != 0 {
                      printf " (%+.1f%%)",100*($NF-ENVIRON["PREV"])/ENVIRON["PREV"]
                    }' \
                  | sed -e 's/ /\&nbsp;/g')
              ((j+=1))
            done
            ((j=0, i+=1))
          done

          # coverage table
          i=0
          j=4
          for s in lines branches
          do
            table[$i,$j]=${s^}
            ((j+=1))

            f=cov/cov.csv
            [ -e $f ] && table[$i,$j]=$( \
              export PREV="$(jq -re '
                  select(.context == "'"cov / $s"'").description
                  | capture("(?<prev_a>[0-9]+)/(?<prev_b>[0-9]+)")
                  | 100*((.prev_a|tonumber) / (.prev_b|tonumber))' \
                prev-status.json || echo 0)"
              ./scripts/cov.py -u $f -f$s -Y \
                | awk -F '[ /%]+' -v s=$s '
                  NR==2 {$1=0; printf "%d/%d %s",$2,$3,s}
                  NR==2 && ENVIRON["PREV"]+0 != 0 {
                    printf " (%+.1f%%)",$4-ENVIRON["PREV"]
                  }' \
                | sed -e 's/ /\&nbsp;/g')
            ((j=4, i+=1))
          done

          # benchmark table
          i=3
          j=4
          for s in readed proged erased
          do
            table[$i,$j]=${s^}
            ((j+=1))

            f=bench/bench.csv
            [ -e $f ] && table[$i,$j]=$( \
              export PREV="$(jq -re '
                  select(.context == "'"bench / $s"'").description
                  | capture("(?<prev>[0-9]+)").prev' \
                prev-status.json || echo 0)"
              ./scripts/summary.py $f -f$s=bench_$s -Y \
                | awk '
                  NR==2 {$1=0; printf "%s B",$NF}
                  NR==2 && ENVIRON["PREV"]+0 != 0 {
                    printf " (%+.1f%%)",100*($NF-ENVIRON["PREV"])/ENVIRON["PREV"]
                  }' \
                | sed -e 's/ /\&nbsp;/g')
            ((j=4, i+=1))
          done

          # build the actual table
          echo "|   | Code | Stack | Structs |   | Coverage |" >> table.txt
          echo "|:--|-----:|------:|--------:|:--|---------:|" >> table.txt
          for ((i=0; i<6; i++))
          do
            echo -n "|" >> table.txt
            for ((j=0; j<6; j++))
            do
              echo -n " " >> table.txt
              [[ i -eq 2 && j -eq 5 ]] && echo -n "**Benchmarks**" >> table.txt
              echo -n "${table[$i,$j]:-}" >> table.txt
              echo -n " |" >> table.txt
            done
            echo >> table.txt
          done

          cat table.txt

      # create a bot comment for successful runs on pull requests
      - name: create-comment
        if: ${{github.event_name == 'pull_request'}}
        run: |
          touch comment.txt
          echo "<details>" >> comment.txt
          echo "<summary>" >> comment.txt
          echo "Tests passed ✓, `
            `Code: $(awk 'NR==3 {print $4}' table.txt || true), `
            `Stack: $(awk 'NR==3 {print $6}' table.txt || true), `
            `Structs: $(awk 'NR==3 {print $8}' table.txt || true)" \
            >> comment.txt
          echo "</summary>" >> comment.txt
          echo >> comment.txt
          [ -e table.txt ] && cat table.txt >> comment.txt
          echo >> comment.txt
          echo "</details>" >> comment.txt
          cat comment.txt

          mkdir -p comment
          jq -n --rawfile comment comment.txt '{
            number: ${{github.event.number}},
            body: $comment,
          }' | tee comment/comment.json
      - name: upload-comment
        uses: actions/upload-artifact@v2
        with:
          name: comment
          path: comment
          retention-days: 1