Git pre-commit hook for prompting to remove binding.pry and debugger lines lines. (Includes a commented example of adding a check for focus in spec files.)

pre-commit

#!/usr/bin/env ruby
hits = []

checks = {
            #'_spec\.rb$' => ['focus:[:space:]*true'],
            '\.rb$' => ['binding\.pry', 'debugger']
         }

# Find the names of all the filenames that have been (A)dded (C)opied or (M)odified
filenames = `git diff --cached --name-only --diff-filter=ACM`.split("\n")

filenames.each do |filename|
  # Perform special checks for _spec filenames (rspec tests)
  checks.each do |filename_pattern, patterns|
    if filename.match filename_pattern
      patterns.each do |contents_pattern|
        results = `git diff --cached  #{filename} | grep "^\+[^+]" | grep "#{contents_pattern}"`.split("\n").map { |r| r.sub(/^\+[\s\t]*/, '') }
        if $? == 0
          # Add the relevant change with line number to the hits array
          results.each{ |r|
            hits.push "#{filename}:" + `grep -n '#{r}' #{filename}`.sub(/:\s+/, ' ').chomp
          }
        end
      end
    end
  end
end

if hits.any?
  puts "\e[33m>>> Please remove the following problems from these files before committing\e[0m"
  puts hits.join("\n")
end

exit 1 if hits.any?