Autofix Rubocop Style/UnpackFirst (#23741)

.rubocop_todo.yml

@@ -2617,10 +2617,3 @@ Style/SymbolArray:
 Style/SymbolProc:
   Exclude:
     - 'spec/lib/request_spec.rb'
-
-# Offense count: 4
-# This cop supports safe autocorrection (--autocorrect).
-Style/UnpackFirst:
-  Exclude:
-    - 'app/models/concerns/account_interactions.rb'
-    - 'lib/paperclip/gif_transcoder.rb'

app/models/concerns/account_interactions.rb

@@ -278,7 +278,7 @@ module AccountInteractions
       followers.where(Account.arel_table[:uri].matches("#{Account.sanitize_sql_like(url_prefix)}/%", false, true)).or(followers.where(uri: url_prefix)).pluck_each(:uri) do |uri|
         Xorcist.xor!(digest, Digest::SHA256.digest(uri))
       end
-      digest.unpack('H*')[0]
+      digest.unpack1('H*')
     end
   end
 
@@ -288,7 +288,7 @@ module AccountInteractions
       followers.where(domain: nil).pluck_each(:username) do |username|
         Xorcist.xor!(digest, Digest::SHA256.digest(ActivityPub::TagManager.instance.uri_for_username(username)))
       end
-      digest.unpack('H*')[0]
+      digest.unpack1('H*')
     end
   end
 

lib/paperclip/gif_transcoder.rb

@@ -57,7 +57,7 @@ class GifReader
           end
 
           # Skip lzw min code size
-          raise InvalidValue unless s.read(1).unpack('C')[0] >= 2
+          raise InvalidValue unless s.read(1).unpack1('C') >= 2
 
           # Skip image data sub-blocks
           skip_sub_blocks!(s)
@@ -77,7 +77,7 @@ class GifReader
   private
 
   def skip_extension_block!(file)
-    if EXTENSION_LABELS.include?(file.read(1).unpack('C')[0])
+    if EXTENSION_LABELS.include?(file.read(1).unpack1('C'))
       block_size, = file.read(1).unpack('C')
       file.seek(block_size, IO::SEEK_CUR)
     end