consistently use += for self assignment

2 files changed, 8 insertions, 8 deletions

diff --git a/lib/asciidoctor/parser.rb b/lib/asciidoctor/parser.rb
index f8e25093..5b11cadc 100644
--- a/lib/asciidoctor/parser.rb
+++ b/lib/asciidoctor/parser.rb
@@ -2571,7 +2571,7 @@ class Parser
           accum = ''
           name = :option
         else
-          accum = accum + c
+          accum += c
         end
       end
 
@@ -2682,16 +2682,16 @@ class Parser
             if c == TAB
               # calculate how many spaces this tab represents, then replace tab with spaces
               if (offset = idx + spaces_added) % tab_size == 0
-                spaces_added += (tab_size - 1)
-                result = result + full_tab_space
+                spaces_added += tab_size - 1
+                result += full_tab_space
               else
                 unless (spaces = tab_size - offset % tab_size) == 1
-                  spaces_added += (spaces - 1)
+                  spaces_added += spaces - 1
                 end
-                result = result + (' ' * spaces)
+                result += ' ' * spaces
               end
             else
-              result = result + c
+              result += c
             end
             idx += 1
           end
diff --git a/lib/asciidoctor/substitutors.rb b/lib/asciidoctor/substitutors.rb
index 15822527..54ae62fe 100644
--- a/lib/asciidoctor/substitutors.rb
+++ b/lib/asciidoctor/substitutors.rb
@@ -1534,7 +1534,7 @@ module Substitutors
         case c
         when ','
           if quote_open
-            accum = accum + c
+            accum += c
           else
             values << accum.strip
             accum = ''
@@ -1542,7 +1542,7 @@ module Substitutors
         when '"'
           quote_open = !quote_open
         else
-          accum = accum + c
+          accum += c
         end
       end
       values << accum.strip