How to run custom shell script file before pre commit hook

Here’s what you could do to use inline bash command as pre-commit hook entry

- repo: local
  hooks:
    - id: pylint-error-count
      name: pylint-error-count
      entry: bash -c 'lines=$(pylint api/ | wc -l) && (( lines > 10)) && exit 1'
      language: system
      types: [python]
      pass_filenames: false

You can also write a script and invoke it this way:

      entry: path/relavite/to/repo/root/pylint_validator.sh
      language: script

NOTE: wc -l is not an accurate count of errors.

EDIT: adding more options

- repo: local
  hooks:
    - id: simple-pylint
      name: simple-pylint
      entry: pylint
      args: ["api/"]
      language: system
      types: [python]
      pass_filenames: false

    - id: inline-pylint-with-bash
      name: inline-pylint-with-bash
      entry: bash -c 'lines=$(pylint api/ | wc -l) && (( lines > 10)) && exit 1'
      language: system
      types: [python]
      pass_filenames: false

    - id: custom-script-file
      name: custom-script-file
      entry: relative/path/to/repo/root/check_pylint.sh
      language: script
      types: [python]
      pass_filenames: false