formula_desc_cop: tweak some rules.

Allow some specific lowercase words and provide an autocorrect for some
of these rules.

1 files changed, 57 insertions, 13 deletions

diff --git a/Library/Homebrew/rubocops/formula_desc_cop.rb b/Library/Homebrew/rubocops/formula_desc_cop.rb
index 54a14b39d..27b00b416 100644
--- a/Library/Homebrew/rubocops/formula_desc_cop.rb
+++ b/Library/Homebrew/rubocops/formula_desc_cop.rb
@@ -8,27 +8,46 @@ module RuboCop
       #
       # - Checks for existence of `desc`
       # - Checks if size of `desc` > 80
-      # - Checks if `desc` begins with an article
-      # - Checks for correct usage of `command-line` in `desc`
-      # - Checks if `desc` contains the formula name
-      class Desc < FormulaCop
+      class DescLength < FormulaCop
         def audit_formula(_node, _class_node, _parent_class_node, body)
           desc_call = find_node_method_by_name(body, :desc)
 
+          # Check if a formula's desc is present
           if desc_call.nil?
             problem "Formula should have a desc (Description)."
             return
           end
 
+          # Check if a formula's desc is too long
           desc = parameters(desc_call).first
           desc_length = "#{@formula_name}: #{string_content(desc)}".length
           max_desc_length = 80
-          if desc_length > max_desc_length
-            problem <<-EOS.undent
-              Description is too long. "name: desc" should be less than #{max_desc_length} characters.
-              Length is calculated as #{@formula_name} + desc. (currently #{desc_length})
-            EOS
-          end
+          return if desc_length <= max_desc_length
+          problem <<-EOS.undent
+            Description is too long. "name: desc" should be less than #{max_desc_length} characters.
+            Length is calculated as #{@formula_name} + desc. (currently #{desc_length})
+          EOS
+        end
+      end
+
+      # This cop audits `desc` in Formulae
+      #
+      # - Checks if `desc` begins with an article
+      # - Checks for correct usage of `command-line` in `desc`
+      # - Checks description starts with a capital letter
+      # - Checks if `desc` contains the formula name
+      class Desc < FormulaCop
+        VALID_LOWERCASE_WORDS = %w[
+          iOS
+          macOS
+          xUnit
+        ].freeze
+
+        def audit_formula(_node, _class_node, _parent_class_node, body)
+          desc_call = find_node_method_by_name(body, :desc)
+          return if desc_call.nil?
+
+          desc = parameters(desc_call).first
 
           # Check if command-line is wrongly used in formula's desc
           if match = regex_match_group(desc, /(command ?line)/i)
@@ -36,16 +55,41 @@ module RuboCop
             problem "Description should use \"#{c}ommand-line\" instead of \"#{match}\""
           end
 
+          # Check if a/an are used in a formula's desc
           if match = regex_match_group(desc, /^(an?)\s/i)
-            problem "Description shouldn't start with an indefinite article (#{match})"
+            problem "Description shouldn't start with an indefinite article i.e. \"#{match.to_s.strip}\""
           end
 
-          if regex_match_group(desc, /^[a-z]/)
+          # Check if invalid uppercase words are at the start of a
+          # formula's desc
+          if !VALID_LOWERCASE_WORDS.include?(string_content(desc).split.first) &&
+             regex_match_group(desc, /^[a-z]/)
             problem "Description should start with a capital letter"
           end
 
           # Check if formula's name is used in formula's desc
-          problem "Description shouldn't include the formula name" if regex_match_group(desc, /^#{@formula_name}\b/i)
+          return unless regex_match_group(desc, /(^|[^a-z])#{@formula_name}([^a-z]|$)/i)
+          problem "Description shouldn't include the formula name"
+        end
+
+        private
+
+        def autocorrect(node)
+          lambda do |corrector|
+            correction = node.source
+            first_word = string_content(node).split.first
+            unless VALID_LOWERCASE_WORDS.include?(first_word)
+              first_char = first_word.to_s.chars.first
+              correction.sub!(/^(['"]?)([a-z])/, "\\1#{first_char.upcase}")
+            end
+            correction.sub!(/^(['"]?)an?\s/i, "\\1")
+            correction.gsub!(/(ommand ?line)/i, "ommand-line")
+            correction.gsub!(/(^|[^a-z])#{@formula_name}([^a-z]|$)/i, "\\1\\2")
+            correction.gsub!(/^(['"]?)\s+/, "\\1")
+            correction.gsub!(/\s+(['"]?)$/, "\\1")
+            corrector.insert_before(node.source_range, correction)
+            corrector.remove(node.source_range)
+          end
         end
       end
     end