Add rake tasks to merge and create Changelog entries

CHANGELOG/new_add_rake_tasks_to_merge_and_create.md

@@ -0,0 +1 @@
+* [#131](https://github.com/rubocop-hq/rubocop-ast/pull/131): Add rake tasks to merge and create Changelog entries. ([@marcandre][])

CONTRIBUTING.md

@@ -61,6 +61,7 @@ Here are a few examples:
 * If this is a breaking change, mark it with `**(Breaking)**`.
 * At the end of the entry, add an implicit link to your GitHub user page as `([@username][])`.
 * If this is your first contribution to RuboCop project, add a link definition for the implicit link to the bottom of the changelog as `[@username]: https://github.com/username`.
+* If it is not your first contribution, you may prefer using `rake cl:new|bug|change` that creates a file with the body of your changelog entry, to be merged later.
 
 [1]: https://github.com/rubocop-hq/rubocop-ast/issues
 [2]: https://www.gun.io/blog/how-to-github-fork-branch-and-pull-request

spec/tasks/changelog_spec.rb

@@ -0,0 +1,73 @@
+# frozen_string_literal: true
+
+returng unless RUBY_VERSION >= '2.6'
+
+require_relative '../../tasks/changelog'
+
+# rubocop:disable RSpec/ExampleLength
+RSpec.describe Changelog do
+  subject(:changelog) do
+    list = entries.to_h { |e| [e.path, e.content] }
+    described_class.new(content: <<~CHANGELOG, entries: list)
+      # Change log
+
+      ## master (unreleased)
+
+      ### New features
+
+      * [#bogus] Bogus feature
+      * [#bogus] Other bogus feature
+
+      ## 0.7.1 (2020-09-28)
+
+      ### Bug fixes
+
+      * [#127](https://github.com/rubocop-hq/rubocop-ast/pull/127): Fix dependency issue for JRuby. ([@marcandre][])
+
+      ## 0.7.0 (2020-09-27)
+
+      ### New features
+
+      * [#105](https://github.com/rubocop-hq/rubocop-ast/pull/105): `NodePattern` compiler [complete rewrite](https://docs.rubocop.org/rubocop-ast/node_pattern_compiler.html). Add support for multiple variadic terms. ([@marcandre][])
+      * [#109](https://github.com/rubocop-hq/rubocop-ast/pull/109): Add `NodePattern` debugging rake tasks: `test_pattern`, `compile`, `parse`. See also [this app](https://nodepattern.herokuapp.com) ([@marcandre][])
+      * [#110](https://github.com/rubocop-hq/rubocop-ast/pull/110): Add `NodePattern` support for multiple terms unions. ([@marcandre][])
+      * [#111](https://github.com/rubocop-hq/rubocop-ast/pull/111): Optimize some `NodePattern`s by using `Set`s. ([@marcandre][])
+      * [#112](https://github.com/rubocop-hq/rubocop-ast/pull/112): Add `NodePattern` support for Regexp literals. ([@marcandre][])
+    CHANGELOG
+  end
+
+  let(:entries) do
+    %i[fix new fix].map.with_index do |type, i|
+      Changelog::Entry.new(type: type, body: "Do something cool#{'x' * i}", user: 'johndoe')
+    end
+  end
+  let(:entry) { entries.first }
+
+  describe Changelog::Entry do
+    it 'generates correct content' do
+      expect(entry.content).to eq <<~MD
+        * [#x](https://github.com/rubocop-hq/rubocop-ast/pull/x): Do something cool. ([@johndoe][])
+      MD
+    end
+  end
+
+  it 'parses correctly' do
+    expect(changelog.rest).to start_with('## 0.7.1 (2020-09-28)')
+  end
+
+  it 'merges correctly' do
+    expect(changelog.unreleased_content).to eq(<<~CHANGELOG)
+      ### New features
+
+      * [#bogus] Bogus feature
+      * [#bogus] Other bogus feature
+      * [#x](https://github.com/rubocop-hq/rubocop-ast/pull/x): Do something coolx. ([@johndoe][])
+
+      ### Bug fixes
+
+      * [#x](https://github.com/rubocop-hq/rubocop-ast/pull/x): Do something cool. ([@johndoe][])
+      * [#x](https://github.com/rubocop-hq/rubocop-ast/pull/x): Do something coolxx. ([@johndoe][])
+    CHANGELOG
+  end
+end
+# rubocop:enable RSpec/ExampleLength

tasks/changelog.rake

@@ -0,0 +1,33 @@
+# frozen_string_literal: true
+
+autoload :Changelog, "#{__dir__}/changelog"
+
+namespace :cl do
+  %i[new fix change].each do |type|
+    desc "Create a Changelog entry (#{type})"
+    task type do
+      path = Changelog::Entry.new(type: type).write
+      cmd = "git add #{path}"
+      system cmd
+      puts "Entry '#{path}' created and added to git index"
+    end
+  end
+
+  desc 'Merge entries and delete them'
+  task :merge do
+    raise 'No entries!' unless Changelog.pending?
+
+    Changelog.new.merge!.and_delete!
+    cmd = "git commit -a -m 'Update Changelog'"
+    puts cmd
+    system cmd
+  end
+
+  task :check_clean do
+    return unless Changelog.pending?
+
+    puts '*** Pending changelog entries!'
+    puts 'Do `bundle exec rake cl:merge`'
+    exit(1)
+  end
+end

tasks/changelog.rb

@@ -0,0 +1,169 @@
+# frozen_string_literal: true
+
+if RUBY_VERSION < '2.6'
+  puts 'Changelog utilities available only for Ruby 2.6+'
+  exit(1)
+end
+
+# Changelog utility
+class Changelog
+  ENTRIES_PATH = 'CHANGELOG/'
+  FIRST_HEADER = /#{Regexp.escape("## master (unreleased)\n")}/m.freeze
+  ENTRIES_PATH_TEMPLATE = "#{ENTRIES_PATH}%<type>s_%<name>s.md"
+  TYPE_REGEXP = /#{Regexp.escape(ENTRIES_PATH)}([a-z]+)_/.freeze
+  TYPE_TO_HEADER = { new: 'New features', fix: 'Bug fixes', change: 'Changes' }.freeze
+  HEADER = /### (.*)/.freeze
+  PATH = 'CHANGELOG.md'
+  REF_URL = 'https://github.com/rubocop-hq/rubocop-ast'
+  MAX_LENGTH = 40
+
+  # New entry
+  # rubocop:disable Metrics/BlockLength
+  Entry = Struct.new(:type, :body, :ref_type, :ref_id, :user, keyword_init: true) do
+    def initialize(type:, body: last_commit_title, ref_type: :pull, ref_id: nil, user: github_user)
+      id, body = extract_id(body)
+      ref_id ||= id || 'x'
+      super
+    end
+
+    def write
+      File.write(path, content)
+      path
+    end
+
+    def path
+      format(ENTRIES_PATH_TEMPLATE, type: type, name: str_to_filename(body))
+    end
+
+    def content
+      period = '.' unless body.end_with? '.'
+      "* #{ref}: #{body}#{period} ([@#{user}][])\n"
+    end
+
+    def ref
+      "[##{ref_id}](#{REF_URL}/#{ref_type}/#{ref_id})"
+    end
+
+    def last_commit_title
+      `git log -1 --pretty=%B`.lines.first.chomp
+    end
+
+    def extract_id(body)
+      /^\[Fixes #(\d+)\] (.*)/.match(body)&.captures || [nil, body]
+    end
+
+    def str_to_filename(str)
+      str
+        .downcase
+        .split
+        .each { |s| s.gsub(/\W/, '') }
+        .reject(&:empty?)
+        .inject do |result, word|
+          s = "#{result}_#{word}"
+          return result if s.length > MAX_LENGTH
+
+          s
+        end
+    end
+
+    def github_user
+      user = `git config --global credential.username`.chomp
+      if user.empty?
+        warn 'Set your username with `git config --global credential.username "myusernamehere"`'
+      end
+
+      user
+    end
+  end
+  # rubocop:enable Metrics/BlockLength
+
+  attr_reader :header, :rest
+
+  def initialize(content: File.read(PATH), entries: Changelog.read_entries)
+    require 'strscan'
+
+    parse(content)
+    @entries = entries
+  end
+
+  def and_delete!
+    @entries.each_key do |path|
+      File.delete(path)
+    end
+  end
+
+  def merge!
+    File.write(PATH, merge_content)
+    self
+  end
+
+  def unreleased_content
+    entry_map = parse_entries(@entries)
+    merged_map = merge_entries(entry_map)
+    merged_map.flat_map do |header, things|
+      [
+        "### #{header}\n",
+        *things,
+        ''
+      ]
+    end.join("\n")
+  end
+
+  def merge_content
+    [
+      @header,
+      unreleased_content,
+      @rest
+    ].join("\n")
+  end
+
+  def self.pending?
+    entry_paths.any?
+  end
+
+  def self.entry_paths
+    Dir["#{ENTRIES_PATH}*"]
+  end
+
+  def self.read_entries
+    entry_paths.to_h do |path|
+      [path, File.read(path)]
+    end
+  end
+
+  private
+
+  def merge_entries(entry_map)
+    all = @unreleased.merge(entry_map) { |_k, v1, v2| v1.concat(v2) }
+    canonical = TYPE_TO_HEADER.values.to_h { |v| [v, nil] }
+    canonical.merge(all).compact
+  end
+
+  def parse(content)
+    ss = StringScanner.new(content)
+    @header = ss.scan_until(FIRST_HEADER)
+    @unreleased = parse_release(ss.scan_until(/\n(?=## )/m))
+    @rest = ss.rest
+  end
+
+  # @return [Hash<type, Array<String>]]
+  def parse_release(unreleased)
+    unreleased
+      .lines
+      .map(&:chomp)
+      .reject(&:empty?)
+      .slice_before(HEADER)
+      .to_h do |header, *entries|
+        [HEADER.match(header)[1], entries]
+      end
+  end
+
+  def parse_entries(path_content_map)
+    changes = Hash.new { |h, k| h[k] = [] }
+    path_content_map.each do |path, content|
+      header = TYPE_TO_HEADER.fetch(TYPE_REGEXP.match(path)[1].to_sym)
+      changes[header].concat(content.lines.map(&:chomp))
+    end
+    changes
+  end
+end

tasks/cut_release.rake

@@ -11,7 +11,7 @@ namespace :cut_release do
   %w[major minor patch pre].each do |release_type|
     desc "Cut a new #{release_type} release, create release notes " \
          'and update documents.'
-    task release_type do
+    task release_type => 'cl:check_clean' do
       run(release_type)
     end
   end
@@ -54,7 +54,7 @@ namespace :cut_release do
 end
 
 desc 'and restore docs/antora'
-task :release do
+task release: 'cl:check_clean' do
   update_file 'docs/antora.yml' do |s|
     s.gsub!(/version: .*/, 'version: master')
   end