version: 2.1

orbs:
  ci-go: ipfs/ci-go@0.1

commands:
  benchcmp:
    parameters:
      before:
        description: "File containing the old benchmarks."
        type: string
      after:
        description: "File containing the new benchmarks."
        type: string
      tolerance:
        description: "Tolerable slowdown (%)."
        type: integer
        default: 25
    environment:
      BEFORE: << parameters.before >>
      AFTER: << parameters.after >>
    steps:
      - run:
          name: "Comparing benchmarks."
          command: |
            parse() {
                sed -n \
                    -e 's/ *\t */\t/g' \
                    -e '/^Benchmark/p' |
                    awk 'BEGIN{print "{\"results\": ["} {print "  {\"name\": \"",$1,"\", \"time\": ",$3," },"} END{print "]}"}' OFS="" ORS=" "|
                    sed -e 's/, ]/ ]/g' |
                    jq '.results[] | {name: .name, time: .time }'

            }
            benchcmp "$BEFORE" "$AFTER"
            echo ""
            echo "Result:"
            {
                parse < "$BEFORE"
                parse < "$AFTER"
            } | jq -e -r -s 'group_by(.name)[] | {name: .[0].name, speedup: (.[0].time / .[1].time)} | select(.speedup < (100 - << parameters.tolerance >>)/100) | "\(.name)\t\(.speedup)x"'
            if [[ $? -ne 4 ]]; then
                echo ""
                echo "FAIL"
                exit 1
            else
                echo "PASS"
            fi

  benchmark:
    parameters:
      output:
        description: "File to write the results to."
        type: string
      branch:
        description: "Branch to benchmark."
        type: string
        default: HEAD
      command:
        description: "Benchmark command."
        type: string
        default: go test -run=NONE -bench=. ./...
    steps:
      - run:
          name: Check out << parameters.branch >>
          command: |
            mkdir /tmp/benchmark
            git --work-tree=/tmp/benchmark checkout << parameters.branch >>
      - run:
          name: "Benchmarking"
          command: |
            {
            << parameters.command >>
            } | tee << parameters.output >>
          working_directory: /tmp/benchmark
          environment:
            IPFS_LOGGING: critical
      - run:
          when: always
          name: Cleanup
          command: rm -rf /tmp/benchmark

jobs:
  benchmark:
    parameters:
      tolerance:
        description: "Tolerable slowdown (%)."
        type: integer
        default: 25
      baseline:
        description: "Baseline branch to which to compare (if any)."
        type: string
        default: ""
      command:
        description: "Benchmark command."
        type: string
        default: go test -run=NONE -bench=. ./...
    executor: ci-go/default
    steps:
      - checkout
      - ci-go/restore-cache
      - benchmark:
          command: << parameters.command >>
          branch: master
          output: ~/benchmark-before.txt
      - benchmark:
          command: << parameters.command >>
          output: ~/benchmark-after.txt
      - benchcmp:
          before: ~/benchmark-before.txt
          after: ~/benchmark-after.txt
          tolerance: << parameters.tolerance >>
      - when:
          condition: << parameters.baseline >>
          steps:
            - benchmark:
                command: << parameters.command >>
                branch: << parameters.baseline >>
                output: ~/benchmark-baseline.txt
            - benchcmp:
                before: ~/benchmark-baseline.txt
                after: ~/benchmark-after.txt
                tolerance: << parameters.tolerance >>
      - ci-go/save-cache

workflows:
  version: 2
  test:
    jobs:
    - ci-go/build
    - ci-go/lint
    - ci-go/test
    - benchmark:
        require: ci-go/test