Bash script which exits with an error if there are too many ESLint problems. Use this gradually reduce the number of problems to zero. https://medium.com/reflections-on-building-software/gradually-reduce-the-number-of-eslint-problems-in-your-codebase-fe503d4f2716

eslint-health

#!/usr/bin/env bash

# Fail if there are too many ESLint problems. The definition of "too many" is
# hardcoded. The number can be manually lowered over time as problems are fixed
# to prevent regressions.
#
# This is a copy of the following Gist:
# https://gist.github.com/openjck/ab1a435e249580861afbc5b93465e611
#
# More information:
# https://medium.com/reflections-on-building-software/gradually-reduce-the-number-of-eslint-problems-in-your-codebase-fe503d4f2716

echo "Running..."
echo

MAX_ESLINT_PROBLEMS=50 # Lower this number over time as problems are fixed
NUM_ESLINT_PROBLEMS=$(npm run lint 2>&1 | grep -E "[0-9]+ problems \(" | cut -f 2 -d ' ')

echo "Max ESLint problems: $MAX_ESLINT_PROBLEMS"
echo "Num ESLint problems: $NUM_ESLINT_PROBLEMS"
echo

if [[ $NUM_ESLINT_PROBLEMS -eq 0 ]]; then
  echo "PASS: No ESLint problems!"
  echo "NOTE: Congratulations! You don't need this script any more. Consider"
  echo "      removing it and running \"npm run lint\" instead."

elif [[ $NUM_ESLINT_PROBLEMS -le $MAX_ESLINT_PROBLEMS ]]; then
  echo "PASS: Number of ESLint problems <= max"

  if [[ $NUM_ESLINT_PROBLEMS -lt $MAX_ESLINT_PROBLEMS ]]; then
    echo "NOTE: Considering lowering MAX_ESLINT_PROBLEMS to $NUM_ESLINT_PROBLEMS"
    echo "      in the eslint-health script to prevent regressions"
  fi

else
  >&2 echo "FAIL: Number of ESLint problems > max"
  >&2 echo "NOTE: Recent changes may have introduced new ESLint problems"
  exit 1

fi