cull_violations_not_in_diff.rb

#!/usr/bin/env ruby
require 'optparse'
require 'pathname'
require 'json'
require 'git_diff_parser'

# This script takes an input .json file in the standard lint format
# and culls violations that do not occur on changed lines for a given diff file.

# Parse command line options.
options = {}
OptionParser.new do |opts|
  opts.banner = 'Usage: cull_violations_not_in_diff.rb [options]'

  opts.on('-i', '--inputfile FILENAME', 'Input filename') { |v| options[:input] = v }
  opts.on('-o', '--output FILENAME', 'Output filename') { |v| options[:output] = v }
  opts.on('-d', '--diff FILENAME', 'Input diff file') { |v| options[:diff] = v }
end.parse!

# Set options or use defaults
input_file = options[:input]
output = options[:output]
diff_file = options[:diff]

file_contents = `cat #{input_file}`
json = JSON.parse(file_contents)
patches = GitDiffParser.parse(File.read(diff_file))

culled_violations = []
json['violation'].each do |v|
    next if patches.files.include?(v['path']) == false # Skip this one

    patch = patches.find_patch_by_file(v['path'])
    if patch.changed_line_numbers.include?(v['startLine'])
        culled_violations.push(v)
    end
end
json['violation'] = culled_violations
output_string = JSON.generate(json)
File.write(output, output_string)