The missing SimpleCov terminal formatter. Shows only missing lines.

simplecov_missing.rb

# frozen_string_literal: true

require 'colorize'
require 'tty-table'

module SimpleCov
  module Formatter
    class MissingFormatter
      def initialize(output = nil)
        @output = output || $stdout
      end

      def format(result)
        has_imperfect_files = print_groups(result)
        print_summary(result, has_imperfect_files)
        @output.puts "\n"
      end

      def color(percent)
        case percent
        when 90..100 then :green
        when 80..90 then :yellow
        else :red
        end
      end

      private

      def print_groups(result)
        has_imperfect_files = false
        result.groups.each do |name, files|
          imperfect_files = files.select { |file| file.covered_percent < 100 }
          next if imperfect_files.empty?

          unless has_imperfect_files
            @output.puts "\nSimpleCov Missing Coverage Report:".colorize(mode: :bold)
            @output.puts '=============================================='
            has_imperfect_files = true
          end

          print_group_header(name, files.covered_percent)
          print_imperfect_files(imperfect_files)
        end
        has_imperfect_files
      end

      def print_group_header(name, covered_percent)
        percentage = covered_percent.round(1)
        emoji = if percentage >= 90
                  '✅'
                else
                  percentage >= 80 ? '⚠️' : '❌'
                end
        header = "  #{emoji} #{name}:  #{percentage.to_s.rjust(5)}%"
        @output.puts "\n#{header}".colorize(color: color(percentage), mode: :bold)
      end

      def print_imperfect_files(files)
        table = TTY::Table.new(header: ['Coverage', 'File', 'Missing Lines'])
        files.sort_by(&:covered_percent).each do |file|
          percentage = file.covered_percent.round(2)
          filename = file.filename.gsub(%r{^#{Dir.pwd}/}, '')
          missed_lines = file.missed_lines.map(&:line_number)
          lines_str = missed_lines.empty? ? '' : format_line_ranges(missed_lines)

          table << [
            "  • #{percentage.to_s.rjust(5)}%".colorize(color(percentage)),
            filename,
            wrap_long_lines(lines_str)
          ]
        end
        @output.puts table.render(:unicode, padding: [0, 1, 0, 1], multiline: true)
      end

      def print_summary(result, has_imperfect_files)
        if has_imperfect_files
          percentage = result.covered_percent.round(1)
          emoji = if percentage >= 90
                    '✅'
                  else
                    percentage >= 80 ? '⚠️' : '❌'
                  end
          summary = "  #{emoji} Total:  #{percentage.to_s.rjust(5)}%"
          @output.puts "\n#{summary}".colorize(color: color(percentage), mode: :bold)
        else
          @output.puts "\n🎉 Perfect Coverage! All files at 100%! 🎉".colorize(color: :green, mode: :bold)
        end
      end

      def format_line_ranges(numbers)
        return '' if numbers.empty?

        ranges = []
        start_num = numbers.first
        prev_num = start_num

        numbers.drop(1).each do |num|
          if num == prev_num + 1
            prev_num = num
          else
            ranges << (start_num == prev_num ? start_num.to_s : "#{start_num}-#{prev_num}")
            start_num = prev_num = num
          end
        end

        ranges << (start_num == prev_num ? start_num.to_s : "#{start_num}-#{prev_num}")
        ranges.join(', ')
      end

      def wrap_long_lines(lines_str)
        return '' if lines_str.empty?

        if lines_str.length > 60
          lines_str.scan(/.{1,60}(?:,|$)/).join("\n").colorize(:red)
        else
          lines_str.colorize(:red)
        end
      end
    end
  end
end