Finds defined and unused methods in a Ruby project

unused_methods.sh

#!/bin/bash

cd /path/to/my/app # Go to the app path

echo "Searching for Ruby method definitions..."

method_names=$(git grep -h -o -E '^ *def +([a-zA-Z_][a-zA-Z0-9_]*)' -- '*.rb' | sed -E 's/^ *def +//' | sort -u)

if [ -z "$method_names" ]; then
    echo "No Ruby method found, or no .rb files found."
    exit 1
fi

echo "Method definitions found, searching for their usage..."

for method in $method_names; do
  # Coun the number of occurrences of the method name in all the files
  count=$(git grep $method -- '*.*' | wc -l | tr -d ' ')

  # If it only occurs once, then it's most probably not used
  if [ "$count" -eq 1 ]; then
    echo "Unused method: $method"
  fi
done

echo "Check complete."