git-hash-str.sh

#!/bin/bash

hash_string() {
  if [[ -z "$1" ]]; then
    echo "Usage: $0 input_string [hash_length]"
    exit 0
  fi
  echo "$1" | git hash-object --stdin | cut -c 1-"${2:-8}"
}

# testing

huston(){
  if [[ -z $any_problems ]]; then
    echo "$(tput setaf 2)ALL PASS $(tput sgr0)"
  else
    echo "$(tput setaf 1)PROBLEMS $(tput sgr0)"
  fi
}


assert_equals() {
  local expected="$1"
  local actual="$2"

  if diff <(echo "$expected") <(echo "$actual"); then
    echo "$(tput setaf 2)PASS $(tput sgr0)"
    true
  else
    echo "$(tput setaf 1)FAIL $(tput sgr0)"
    any_problems=true
    false
  fi
}


run_tests() {
  assert_equals "Usage:" "$(hash_string | cut -d" " -f1)"

  assert_equals "ce013625" "$(hash_string "hello")"
  assert_equals "ce0136" "$(hash_string "hello" 6)"
  assert_equals "cc628ccd" "$(hash_string "world")"
  huston
}

# main
if [[ "$1" == "--test" ]] || [[ "$1" == "-t" ]]; then
  run_tests
else
  hash_string "$1" "$2"
fi