A bash function that creates git worktrees for feature branches with a standardized naming convention.

FeatureWorktree.sh

#!/usr/bin/env bash

# Creates a git worktree for a feature branch and navigates into it.
#
# Creates a new git worktree in the parent directory of the current
# repository.
#
# The worktree directory is named "{repoName}-{FeatureBranchName}" and
# the branch is created as "tiagoa/{FeatureBranchName}".
#
# By default, the new branch is based off 'main'. Use --current to branch
# from HEAD, or --branch to specify a different base branch.
#
# To install, the quickest way is to dot-source this script in your
# .bashrc/.zshrc.

# ── Private helpers (namespaced to avoid polluting the global scope) ──────────

__nfwt_err() {
  printf 'Error: %s\n' "$*" >&2
}

__nfwt_usage() {
  cat <<'EOF'
Usage:
  nfwt <feature-branch-name> [--current | --branch <base-branch>]

Description:
  Creates a git worktree in the parent directory of the current repository.
  Worktree directory name: {repoName}-{feature-branch-name}
  New branch name:       tiagoa/{feature-branch-name}

Options:
  -c, --current           Branch from current HEAD
  -b, --branch <name>     Branch from a specific base branch
  -h, --help              Show this help

Examples:
  nfwt my-feature
  nfwt my-feature --current
  nfwt my-feature --branch develop
EOF
}

# ── Main function ────────────────────────────────────────────────────────────

new_feature_worktree() {
  local feature_branch_name
  local use_current=false
  local base_branch=""
  local base_ref
  local git_root
  local repo_name
  local parent_dir
  local branch_name
  local worktree_dir
  local branches

  if [[ $# -lt 1 ]]; then
    __nfwt_usage >&2
    return 64
  fi

  feature_branch_name="$1"
  shift

  if [[ -z "${feature_branch_name}" ]]; then
    __nfwt_err "Feature branch name cannot be empty."
    return 64
  fi

  while [[ $# -gt 0 ]]; do
    case "$1" in
      -c|--current)
        if [[ -n "${base_branch}" ]]; then
          __nfwt_err "--current and --branch cannot be used together."
          return 64
        fi
        use_current=true
        shift
        ;;
      -b|--branch)
        if [[ "${use_current}" == true ]]; then
          __nfwt_err "--current and --branch cannot be used together."
          return 64
        fi
        if [[ $# -lt 2 || -z "${2}" ]]; then
          __nfwt_err "--branch requires a non-empty branch name."
          return 64
        fi
        base_branch="$2"
        shift 2
        ;;
      -h|--help)
        __nfwt_usage
        return 0
        ;;
      --)
        shift
        break
        ;;
      *)
        __nfwt_err "Unknown option: $1"
        __nfwt_usage >&2
        return 64
        ;;
    esac
  done

  if [[ $# -gt 0 ]]; then
    __nfwt_err "Unexpected extra arguments: $*"
    __nfwt_usage >&2
    return 64
  fi

  if ! command -v git >/dev/null 2>&1; then
    __nfwt_err "git is not installed or not available in PATH."
    return 69
  fi

  if ! git_root="$(git rev-parse --show-toplevel 2>/dev/null)"; then
    __nfwt_err "Not inside a git repository."
    return 128
  fi

  if [[ ! -d "${git_root}" ]]; then
    __nfwt_err "Resolved repository root does not exist: ${git_root}"
    return 70
  fi

  repo_name="$(basename "${git_root}")"
  parent_dir="$(dirname "${git_root}")"

  if [[ "${use_current}" == true ]]; then
    base_ref='HEAD'
  elif [[ -n "${base_branch}" ]]; then
    base_ref="${base_branch}"
  else
    base_ref='main'
  fi

  if [[ "${base_ref}" != 'HEAD' ]]; then
    if ! git rev-parse --verify "${base_ref}" >/dev/null 2>&1; then
      branches="$(git branch --list --format='%(refname:short)' 2>/dev/null || true)"
      __nfwt_err "Base branch '${base_ref}' does not exist."
      if [[ -n "${branches}" ]]; then
        printf 'Available branches:\n%s\n' "${branches}" >&2
      fi
      return 65
    fi
  fi

  branch_name="tiagoa/${feature_branch_name}"
  worktree_dir="${parent_dir}/${repo_name}-${feature_branch_name}"

  if [[ -e "${worktree_dir}" ]]; then
    __nfwt_err "Directory already exists: ${worktree_dir}"
    return 73
  fi

  if git show-ref --verify --quiet "refs/heads/${branch_name}"; then
    __nfwt_err "Branch already exists locally: ${branch_name}"
    return 68
  fi

  printf "Creating worktree at '%s' with branch '%s' from '%s'...\n" "${worktree_dir}" "${branch_name}" "${base_ref}"

  if ! git worktree add -b "${branch_name}" "${worktree_dir}" "${base_ref}"; then
    __nfwt_err "Failed to create git worktree."
    return 74
  fi

  printf 'Worktree created successfully.\n'

  if ! cd "${worktree_dir}"; then
    __nfwt_err "Worktree was created but failed to change directory to: ${worktree_dir}"
    return 75
  fi
}

# Alias for convenience (matches the PowerShell 'nfwt' alias).
# Source this file in your .bashrc / .zshrc:
#   source /path/to/FeatureWorktree.sh
nfwt() {
  new_feature_worktree "$@"
}