GitHub Actions running 5 tslint jobs in parallel (each tests every 5th file)

ci.yml

name: CI

on: [push]

jobs:
  tslint:
    runs-on: ubuntu-latest
    strategy:
      matrix:
        job: [0, 1, 2, 3, 4]
    steps:
      - uses: actions/checkout@v1
      - run: |
          npm ci
          find . -name '*.ts' -not -name '*.d.ts' -not -path './node_modules/*' | sort | \
            awk "NR % $NUM_JOBS == $JOB" | xargs npm run tslint --
        env:
          NUM_JOBS: 5
          JOB: ${{ matrix.job }}

package.json

{
  "scripts": {
    "tslint": "tslint -p tsconfig.json -t codeFrame"
  }
}

Could also do:

xargs -n 100 npm run tslint --

to limit each tslint run to 100 files, and if you've got parallel CPU spare, and then you could do:

xargs -n 100 -P 4 npm run tslint --

which will run 4 tslint processes in parallel with 100 files each

(that is, 4 processes in parallel on each of the 5 CI jobs – for a total of 20 tslint processes in parallel)