download_git_clone_idempotent_to

#!/usr/bin/env sh

(
  download_git_clone_idempotent_to() {
    # Download file to BIN_PATH
    # default BIN_PATH to the first entry of the PATH environment variable that ends on 'local/bin'.
    BIN_PATH="${1:-$(
      BIN_PATH="${PATH%${PATH#*local/bin}}"  
      printf "${BIN_PATH##*:}/git-clone-idempotent"
    )}"
    test ! -e "${BIN_PATH?}" || { printf 'File already exists.\n' >&2 ; exit 1 ; }
    # test "${PATH:-}" != "${PATH#*${BIN_PATH%/*}}" || { printf 'BIN_PATH is not in PATH.\n' >&2 ; exit 1 ; }
    $(
      command -v curl && printf ' --output' ||
      {
        command -v wget && printf ' --output-document' ||
          printf 'eval >&2 printf '\''Could not download "%%s" from "%%s".\\n'\'
      }
    ) "${BIN_PATH?}" https://raw.githubusercontent.com/imme-emosol/git-clone-idempotent/patch-1/index.sh
    test -e "${BIN_PATH?}" || exit 1

    # Look at what was downloaded before using it.
    $( command -v sensible-editor || printf cat ) "${BIN_PATH?}"
    printf 'Type y<Enter> to make the file executable.\n' >&2
    read -r CONFIRM
    # Make the file executable.
    test "confirmed_${CONFIRM}" != "confirmed_y" || chmod u+x "${BIN_PATH?}"
  }
  
  printf 'Press <Enter> to download to default location.
Anything else will be the path to downloaded to.\n' >&2
  read -r LOCATION
  # Remove the "git-clone-idempotent" to download the file into PATH.
  download_git_clone_idempotent_to "${LOCATION:-}"
)