Encapsulate formula desc offense checking logic into methods

1 files changed, 47 insertions, 41 deletions

diff --git a/Library/Homebrew/rubocops/formula_desc_cop.rb b/Library/Homebrew/rubocops/formula_desc_cop.rb
index dcd928d28..d276be5cc 100644
--- a/Library/Homebrew/rubocops/formula_desc_cop.rb
+++ b/Library/Homebrew/rubocops/formula_desc_cop.rb
@@ -13,6 +13,9 @@ module RuboCop
       # - Checks if `desc` contains the formula name
 
       class FormulaDesc < FormulaCop
+        attr_accessor :formula_name, :description, :source_buffer, :line_number, :line_begin_pos,
+                      :desc_begin_pos, :call_node
+
         def audit_formula(node, class_node, _parent_class_node, body)
           check(node, body, class_node.const_name)
         end
@@ -23,55 +26,58 @@ module RuboCop
           body.each_child_node(:send) do |call_node|
             _receiver, call_name, args = *call_node
             next if call_name != :desc || args.children[0].empty?
-            description = args.children[0]
-
-            source_buffer = call_node.source_range.source_buffer
-            line_number = call_node.loc.line
-            line_begin_pos = call_node.source_range.source_buffer.line_range(call_node.loc.line).begin_pos
-            desc_begin_pos = call_node.children[2].source_range.begin_pos
+            @formula_name = formula_name
+            @description = args.children[0]
+            @source_buffer = call_node.source_range.source_buffer
+            @line_number = call_node.loc.line
+            @line_begin_pos = call_node.source_range.source_buffer.line_range(call_node.loc.line).begin_pos
+            @desc_begin_pos = call_node.children[2].source_range.begin_pos
+            @call_node = call_node
 
-            linelength = "#{formula_name}: #{description}".length
-            if linelength > 80
-              column = desc_begin_pos - line_begin_pos
-              length = call_node.children[2].source_range.size
-              sourcerange = source_range(source_buffer, line_number, column, length)
-              message = <<-EOS.undent
-                Description is too long. "name: desc" should be less than 80 characters.
-                Length is calculated as #{formula_name} + desc. (currently #{linelength})
-              EOS
-              add_offense(call_node, sourcerange, message)
-            end
+            check_for_desc_length_offense
 
-            match_object = description.match(/(command ?line)/i)
-            if match_object
-              column = desc_begin_pos+match_object.begin(0)-line_begin_pos+1
-              length = match_object.to_s.length
-              sourcerange = source_range(source_buffer, line_number, column, length)
-              message = "Description should use \"command-line\" instead of \"#{match_object}\""
-              add_offense(call_node, sourcerange, message)
-            end
+            check_for_offense(/(command ?line)/i,
+                              "Description should use \"command-line\" instead of \"%s\"")
 
-            match_object = description.match(/^(an?)\s/i)
-            if match_object
-              column = desc_begin_pos+match_object.begin(0)-line_begin_pos+1
-              length = match_object.to_s.length
-              sourcerange = source_range(source_buffer, line_number, column, length)
-              message = "Description shouldn't start with an indefinite article (#{match_object})"
-              add_offense(call_node, sourcerange, message)
-            end
+            check_for_offense(/^(an?)\s/i,
+                              "Description shouldn't start with an indefinite article (%s)")
 
-            match_object = description.match(/^#{formula_name}/i)
-            if match_object
-              column = desc_begin_pos+match_object.begin(0)-line_begin_pos+1
-              length = match_object.to_s.length
-              sourcerange = source_range(source_buffer, line_number, column, length)
-              message = "Description shouldn't include the formula name"
-              add_offense(call_node, sourcerange, message)
-            end
+            check_for_offense(/^#{formula_name}/i,
+                              "Description shouldn't include the formula name")
             return nil
           end
           add_offense(node, node.source_range, "Formula should have a desc (Description).")
         end
+
+        def check_for_offense(regex, offense_msg)
+          # This method checks if particular regex has a match within formula's desc
+          # If so, adds a violation
+          match_object = @description.match(regex)
+          if match_object
+            column = @desc_begin_pos + match_object.begin(0) - @line_begin_pos + 1
+            length = match_object.to_s.length
+            offense_source_range = source_range(source_buffer, @line_number, column, length)
+            offense_msg = offense_msg % [match_object]
+            add_offense(@call_node, offense_source_range, offense_msg)
+          end
+        end
+
+        def check_for_desc_length_offense
+          # This method checks if desc length > max_desc_length
+          # If so, adds a violation
+          desc_length = "#{@formula_name}: #{@description}".length
+          max_desc_length = 80
+          if desc_length > max_desc_length
+            column = @desc_begin_pos - @line_begin_pos
+            length = @call_node.children[2].source_range.size
+            offense_source_range = source_range(source_buffer, @line_number, column, length)
+            desc_length_offense_msg = <<-EOS.undent
+              Description is too long. "name: desc" should be less than #{max_desc_length} characters.
+              Length is calculated as #{@formula_name} + desc. (currently #{"#{@formula_name}: #{@description}".length})
+            EOS
+            add_offense(@call_node, offense_source_range, desc_length_offense_msg)
+          end
+        end
       end
     end
   end