Worktree-aware branch switcher: cd to existing worktree instead of failing

worktree-nav.sh

# Worktree-aware branch switcher
#
# The problem: git won't let you checkout a branch that's already open in a
# worktree. The error message tells you exactly where to go — so why not just
# go there automatically?
#
#   $ git checkout some-branch
#   fatal: 'some-branch' is already checked out at '/Users/dan/work/admin.worktrees/some-branch'
#
# Instead of copying that path, this alias catches the error and cd's there.
# Branch names are easy to find (GitHub PR, Linear ticket); worktree paths are not.
#
# Usage: switch [branch]   — defaults to "staging"
#
# Note: customize the two hardcoded values below for your setup:
#   ~/work/admin      — the root git repo (not a worktree)
#   "staging"         — the default branch when none is provided

switch() {
  cd ~/work/admin && nvm use  # <-- change to your repo path
  local branch="${1:-staging}"  # <-- change default branch if needed
  local output
  output=$(git checkout "$branch" 2>&1)
  local exit_code=$?

  if [[ $exit_code -eq 0 ]]; then
    echo "$output"
  elif [[ "$output" =~ "already checked out at '([^']+)'" ]]; then
    echo "Already in worktree, switching to: ${match[1]}"
    cd "${match[1]}" && nvm use
  else
    echo "$output" >&2
    return $exit_code
  fi
}