Add breaking-changes section to changelog (#530)

* add breaking-changes section to changelog

* Clean up parse_by_sections

* Thank you bastelfreak and ekohl!

lib/github_changelog_generator/generator/generator.rb

@@ -95,12 +95,13 @@ module GitHubChangelogGenerator
     # @param [Array] pull_requests
     # @return [String] generated log for issues
     def issues_to_log(issues, pull_requests)
-      log = ""
-      bugs_a, enhancement_a, issues_a = parse_by_sections(issues, pull_requests)
+      sections = parse_by_sections(issues, pull_requests)
 
-      log += generate_sub_section(enhancement_a, options[:enhancement_prefix])
-      log += generate_sub_section(bugs_a, options[:bug_prefix])
-      log += generate_sub_section(issues_a, options[:issue_prefix])
+      log = ""
+      log += generate_sub_section(sections[:breaking], options[:breaking_prefix])
+      log += generate_sub_section(sections[:enhancement], options[:enhancement_prefix])
+      log += generate_sub_section(sections[:bugs], options[:bug_prefix])
+      log += generate_sub_section(sections[:issues], options[:issue_prefix])
       log
     end
 
@@ -109,47 +110,69 @@ module GitHubChangelogGenerator
     #
     # @param [Array] issues
     # @param [Array] pull_requests
-    # @return [Array] tuple of filtered arrays: (Bugs, Enhancements Issues)
+    # @return [Hash] Mapping of filtered arrays: (Bugs, Enhancements, Breaking stuff, Issues)
     def parse_by_sections(issues, pull_requests)
-      issues_a = []
-      enhancement_a = []
-      bugs_a = []
+      sections = {
+        issues: [],
+        enhancements: [],
+        bugs: [],
+        breaking: []
+      }
 
       issues.each do |dict|
         added = false
+
         dict["labels"].each do |label|
           if options[:bug_labels].include?(label["name"])
-            bugs_a.push(dict)
+            sections[:bugs] << dict
             added = true
-            next
-          end
-          if options[:enhancement_labels].include?(label["name"])
-            enhancement_a.push(dict)
+          elsif options[:enhancement_labels].include?(label["name"])
+            sections[:enhancements] << dict
+            added = true
+          elsif options[:breaking_labels].include?(label["name"])
+            sections[:breaking] << dict
             added = true
-            next
           end
+
+          break if added
         end
-        issues_a.push(dict) unless added
+
+        sections[:issues] << dict unless added
       end
 
+      sort_pull_requests(pull_requests, sections)
+    end
+
+    # This method iterates through PRs and sorts them into sections
+    #
+    # @param [Array] pull_requests
+    # @param [Hash] sections
+    # @return [Hash] sections
+    def sort_pull_requests(pull_requests, sections)
       added_pull_requests = []
       pull_requests.each do |pr|
+        added = false
+
         pr["labels"].each do |label|
           if options[:bug_labels].include?(label["name"])
-            bugs_a.push(pr)
-            added_pull_requests.push(pr)
-            next
-          end
-          if options[:enhancement_labels].include?(label["name"])
-            enhancement_a.push(pr)
-            added_pull_requests.push(pr)
-            next
+            sections[:bugs] << pr
+            added_pull_requests << pr
+            added = true
+          elsif options[:enhancement_labels].include?(label["name"])
+            sections[:enhancements] << pr
+            added_pull_requests << pr
+            added = true
+          elsif options[:breaking_labels].include?(label["name"])
+            sections[:breaking] << pr
+            added_pull_requests << pr
+            added = true
           end
+
+          break if added
         end
       end
       added_pull_requests.each { |p| pull_requests.delete(p) }
-
-      [bugs_a, enhancement_a, issues_a]
+      sections
     end
   end
 end

lib/github_changelog_generator/options.rb

@@ -20,6 +20,8 @@ module GitHubChangelogGenerator
       due_tag
       enhancement_labels
       enhancement_prefix
+      breaking_labels
+      breaking_prefix
       exclude_labels
       exclude_tags
       exclude_tags_regex

lib/github_changelog_generator/parser.rb

@@ -70,6 +70,9 @@ module GitHubChangelogGenerator
         opts.on("--enhancement-label [LABEL]", "Setup custom label for enhancements section. Default is \"**Implemented enhancements:**\"") do |v|
           options[:enhancement_prefix] = v
         end
+        opts.on("--breaking-label [LABEL]", "Setup custom label for the breaking changes section. Default is \"**Breaking changes:**\"") do |v|
+          options[:breaking_prefix] = v
+        end
         opts.on("--issues-label [LABEL]", "Setup custom label for closed-issues section. Default is \"**Closed issues:**\"") do |v|
           options[:issue_prefix] = v
         end
@@ -127,6 +130,9 @@ module GitHubChangelogGenerator
         opts.on("--enhancement-labels  x,y,z", Array, 'Issues with the specified labels will be always added to "Implemented enhancements" section. Default is \'enhancement,Enhancement\'') do |list|
           options[:enhancement_labels] = list
         end
+        opts.on("--breaking-labels x,y,z", Array, 'Issues with these labels will be added to a new section, called "Breaking Changes". Default is \'backwards-incompatible\'') do |list|
+          options[:breaking_labels] = list
+        end
         opts.on("--issue-line-labels x,y,z", Array, 'The specified labels will be shown in brackets next to each matching issue. Use "ALL" to show all labels. Default is [].') do |list|
           options[:issue_line_labels] = list
         end
@@ -208,6 +214,7 @@ module GitHubChangelogGenerator
         enhancement_labels: ["enhancement", "Enhancement", "Type: Enhancement"],
         bug_labels: ["bug", "Bug", "Type: Bug"],
         exclude_labels: ["duplicate", "question", "invalid", "wontfix", "Duplicate", "Question", "Invalid", "Wontfix", "Meta: Exclude From Changelog"],
+        breaking_labels: %w[backwards-incompatible breaking],
         issue_line_labels: [],
         max_issues: nil,
         simple_list: false,
@@ -218,6 +225,7 @@ module GitHubChangelogGenerator
         issue_prefix: "**Closed issues:**",
         bug_prefix: "**Fixed bugs:**",
         enhancement_prefix: "**Implemented enhancements:**",
+        breaking_prefix: "**Breaking changes:**",
         http_cache: true
       )
     end

lib/github_changelog_generator/parser_file.rb

@@ -67,7 +67,7 @@ module GitHubChangelogGenerator
     end
 
     KNOWN_ARRAY_KEYS = %i[exclude_labels include_labels bug_labels
-                          enhancement_labels issue_line_labels between_tags exclude_tags]
+                          enhancement_labels breaking_labels issue_line_labels between_tags exclude_tags]
     KNOWN_INTEGER_KEYS = [:max_issues]
 
     def convert_value(value, option_name)
@@ -91,6 +91,7 @@ module GitHubChangelogGenerator
       header_label: :header,
       front_matter: :frontmatter,
       pr_label: :merge_prefix,
+      breaking_label: :breaking_prefix,
       issues_wo_labels: :add_issues_wo_labels,
       pr_wo_labels: :add_pr_wo_labels,
       pull_requests: :pulls,