dev

#!/usr/bin/env bash
# The project's dev server or test watcher, run with the package manager its
# lockfile names (npm, pnpm, yarn or bun):
#
#   dev server   the "dev" script, else "start"
#   dev test     Vitest or Jest watching, starting with the tests your changes touch
#
# In iTerm2 the tab's status dot follows along (triggers in config/iterm2).
set -euo pipefail

usage() {
  sed -n '2,8p' "$0" | sed -E 's/^# ?//'
}

# The nearest package.json at or above the current folder
project() {
  local dir=$PWD
  while [[ "$dir" != / ]]; do
    if [[ -f "$dir/package.json" ]]; then
      echo "$dir"
      return 0
    fi
    dir=$(dirname "$dir")
  done
  return 1
}

# In a monorepo the lockfile sits at the root, above the package
package_manager() {
  local dir=$1
  while :; do
    if [[ -f "$dir/pnpm-lock.yaml" ]]; then
      echo pnpm
      return
    elif [[ -f "$dir/yarn.lock" ]]; then
      echo yarn
      return
    elif [[ -f "$dir/bun.lock" || -f "$dir/bun.lockb" ]]; then
      echo bun
      return
    elif [[ -f "$dir/package-lock.json" || "$dir" == / ]]; then
      echo npm
      return
    fi
    dir=$(dirname "$dir")
  done
}

has_script() { # <project> <script>
  node -e 'process.exit(require(process.argv[1]).scripts?.[process.argv[2]] ? 0 : 1)' "$1/package.json" "$2"
}

# Vitest or Jest, whichever the project's package.json names. A monorepo often
# installs its runner only at the top: without one of its own, the project gets
# the nearest one above, up to the monorepo's root, as npx finds it, unless the
# project's test script runs something else
test_runner() { # <project>
  node -e '
const fs = require("fs")
const path = require("path")
const read = (dir) => {
  try {
    return JSON.parse(fs.readFileSync(path.join(dir, "package.json"), "utf8"))
  } catch {
    return undefined
  }
}
const runner = (p) => ["vitest", "jest"].find((name) => ({ ...p?.dependencies, ...p?.devDependencies })[name])
const top = (dir, p) => p?.workspaces || fs.existsSync(path.join(dir, "pnpm-workspace.yaml")) || dir === path.dirname(dir)
let dir = process.argv[1]
const project = read(dir)
let found = runner(project)
for (let p = project; !found && !top(dir, p); ) {
  dir = path.dirname(dir)
  p = read(dir)
  found = runner(p)
}
const script = project?.scripts?.test
if (found && (runner(project) || !script || script.split(/[\s;&|()]+/).includes(found))) {
  console.log(found)
}' "$1"
}

in_iterm() {
  [[ "${TERM_PROGRAM:-}" == iTerm.app || "${LC_TERMINAL:-}" == iTerm2 ]]
}

status() { # <text> <dot colour>
  if in_iterm; then printf '\e]21337;status=%s;indicator=%s\a' "$1" "$2"; fi
}

clear_status() {
  if in_iterm; then printf '\e]21337;status=;indicator=;status-color=\a'; fi
}

case "${1:-}" in
  server | test) ;;
  -h | --help)
    usage
    exit 0
    ;;
  *)
    usage >&2
    exit 2
    ;;
esac

dir=$(project) || {
  echo "dev: no package.json here or above" >&2
  exit 1
}
pm=$(package_manager "$dir")
case "$pm" in
  npm) run=(npm run) exec=(npx) ;;
  pnpm) run=(pnpm run) exec=(pnpm exec) ;;
  yarn) run=(yarn run) exec=(yarn) ;;
  bun) run=(bun run) exec=(bunx) ;;
esac

if [[ "$1" == server ]]; then
  if has_script "$dir" dev; then
    cmd=("${run[@]}" dev)
  elif has_script "$dir" start; then
    cmd=("${run[@]}" start)
  else
    echo "dev: $dir/package.json has no dev or start script" >&2
    exit 1
  fi
  state=starting
else
  runner=$(test_runner "$dir")
  if [[ "$runner" == vitest ]]; then
    cmd=("${exec[@]}" vitest --changed)
  elif [[ "$runner" == jest ]]; then
    cmd=("${exec[@]}" jest --watch)
  elif has_script "$dir" test; then
    cmd=("${run[@]}" test)
  else
    echo "dev: no Vitest, Jest or test script in $dir/package.json" >&2
    exit 1
  fi
  state=testing
fi

cd "$dir"
echo "→ ${cmd[*]}"
trap clear_status EXIT
status "$state" '#d29922'
"${cmd[@]}"