Enable even more frozen string in lib/gitlab

Enables frozen string for the following:

* lib/gitlab/fogbugz_import/**/*.rb
* lib/gitlab/gfm/**/*.rb
* lib/gitlab/git/**/*.rb
* lib/gitlab/gitaly_client/**/*.rb
* lib/gitlab/gitlab_import/**/*.rb
* lib/gitlab/google_code_import/**/*.rb
* lib/gitlab/gpg/**/*.rb
* lib/gitlab/grape_logging/**/*.rb
* lib/gitlab/graphql/**/*.rb
* lib/gitlab/graphs/**/*.rb
* lib/gitlab/hashed_storage/**/*.rb
* lib/gitlab/health_checks/**/*.rb

Partially address gitlab-org/gitlab-ce#47424.

23 files changed, 63 insertions, 15 deletions

diff --git a/lib/gitlab/gitaly_client/attributes_bag.rb b/lib/gitlab/gitaly_client/attributes_bag.rb
index 198a1de91c7..3f1a0ef4888 100644
--- a/lib/gitlab/gitaly_client/attributes_bag.rb
+++ b/lib/gitlab/gitaly_client/attributes_bag.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module GitalyClient
     # This module expects an `ATTRS` const to be defined on the subclass
diff --git a/lib/gitlab/gitaly_client/blob_service.rb b/lib/gitlab/gitaly_client/blob_service.rb
index 086ce31e678..39547328210 100644
--- a/lib/gitlab/gitaly_client/blob_service.rb
+++ b/lib/gitlab/gitaly_client/blob_service.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module GitalyClient
     class BlobService
@@ -15,7 +17,7 @@ module Gitlab
         )
         response = GitalyClient.call(@gitaly_repo.storage_name, :blob_service, :get_blob, request, timeout: GitalyClient.fast_timeout)
 
-        data = ''
+        data = []
         blob = nil
         response.each do |msg|
           if blob.nil?
@@ -27,6 +29,8 @@ module Gitlab
 
         return nil if blob.oid.blank?
 
+        data = data.join
+
         Gitlab::Git::Blob.new(
           id: blob.oid,
           size: blob.size,
diff --git a/lib/gitlab/gitaly_client/blobs_stitcher.rb b/lib/gitlab/gitaly_client/blobs_stitcher.rb
index 5ca592ff812..01bab854082 100644
--- a/lib/gitlab/gitaly_client/blobs_stitcher.rb
+++ b/lib/gitlab/gitaly_client/blobs_stitcher.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module GitalyClient
     class BlobsStitcher
diff --git a/lib/gitlab/gitaly_client/commit_service.rb b/lib/gitlab/gitaly_client/commit_service.rb
index 085b2a127a5..4e46cb9f05c 100644
--- a/lib/gitlab/gitaly_client/commit_service.rb
+++ b/lib/gitlab/gitaly_client/commit_service.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module GitalyClient
     class CommitService
@@ -93,7 +95,7 @@ module Gitlab
         response = GitalyClient.call(@repository.storage, :commit_service, :tree_entry, request, timeout: GitalyClient.medium_timeout)
 
         entry = nil
-        data = ''
+        data = []
         response.each do |msg|
           if entry.nil?
             entry = msg
@@ -103,7 +105,7 @@ module Gitlab
 
           data << msg.data
         end
-        entry.data = data
+        entry.data = data.join
 
         entry unless entry.oid.blank?
       end
@@ -254,7 +256,7 @@ module Gitlab
         )
 
         response = GitalyClient.call(@repository.storage, :commit_service, :raw_blame, request, timeout: GitalyClient.medium_timeout)
-        response.reduce("") { |memo, msg| memo << msg.data }
+        response.reduce([]) { |memo, msg| memo << msg.data }.join
       end
 
       def find_commit(revision)
@@ -345,8 +347,8 @@ module Gitlab
         request = Gitaly::ExtractCommitSignatureRequest.new(repository: @gitaly_repo, commit_id: commit_id)
         response = GitalyClient.call(@repository.storage, :commit_service, :extract_commit_signature, request)
 
-        signature = ''.b
-        signed_text = ''.b
+        signature = +''.b
+        signed_text = +''.b
 
         response.each do |message|
           signature << message.signature
@@ -364,7 +366,7 @@ module Gitlab
         request = Gitaly::GetCommitSignaturesRequest.new(repository: @gitaly_repo, commit_ids: commit_ids)
         response = GitalyClient.call(@repository.storage, :commit_service, :get_commit_signatures, request, timeout: GitalyClient.fast_timeout)
 
-        signatures = Hash.new { |h, k| h[k] = [''.b, ''.b] }
+        signatures = Hash.new { |h, k| h[k] = [+''.b, +''.b] }
         current_commit_id = nil
 
         response.each do |message|
@@ -383,7 +385,7 @@ module Gitlab
         request = Gitaly::GetCommitMessagesRequest.new(repository: @gitaly_repo, commit_ids: commit_ids)
         response = GitalyClient.call(@repository.storage, :commit_service, :get_commit_messages, request, timeout: GitalyClient.fast_timeout)
 
-        messages = Hash.new { |h, k| h[k] = ''.b }
+        messages = Hash.new { |h, k| h[k] = +''.b }
         current_commit_id = nil
 
         response.each do |rpc_message|
diff --git a/lib/gitlab/gitaly_client/conflict_files_stitcher.rb b/lib/gitlab/gitaly_client/conflict_files_stitcher.rb
index c275a065bce..0e00f6e8c44 100644
--- a/lib/gitlab/gitaly_client/conflict_files_stitcher.rb
+++ b/lib/gitlab/gitaly_client/conflict_files_stitcher.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module GitalyClient
     class ConflictFilesStitcher
@@ -17,7 +19,7 @@ module Gitlab
 
               current_file = file_from_gitaly_header(gitaly_file.header)
             else
-              current_file.raw_content << gitaly_file.content
+              current_file.raw_content = "#{current_file.raw_content}#{gitaly_file.content}"
             end
           end
         end
diff --git a/lib/gitlab/gitaly_client/conflicts_service.rb b/lib/gitlab/gitaly_client/conflicts_service.rb
index aa7e03301f5..6304f998563 100644
--- a/lib/gitlab/gitaly_client/conflicts_service.rb
+++ b/lib/gitlab/gitaly_client/conflicts_service.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module GitalyClient
     class ConflictsService
diff --git a/lib/gitlab/gitaly_client/diff.rb b/lib/gitlab/gitaly_client/diff.rb
index af9d674535b..dd192ccde1a 100644
--- a/lib/gitlab/gitaly_client/diff.rb
+++ b/lib/gitlab/gitaly_client/diff.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module GitalyClient
     class Diff
diff --git a/lib/gitlab/gitaly_client/diff_stitcher.rb b/lib/gitlab/gitaly_client/diff_stitcher.rb
index da243ee2d1a..98d327a7329 100644
--- a/lib/gitlab/gitaly_client/diff_stitcher.rb
+++ b/lib/gitlab/gitaly_client/diff_stitcher.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module GitalyClient
     class DiffStitcher
@@ -20,7 +22,7 @@ module Gitlab
 
             current_diff = GitalyClient::Diff.new(diff_params)
           else
-            current_diff.patch += diff_msg.raw_patch_data
+            current_diff.patch = "#{current_diff.patch}#{diff_msg.raw_patch_data}"
           end
 
           if diff_msg.end_of_patch
diff --git a/lib/gitlab/gitaly_client/health_check_service.rb b/lib/gitlab/gitaly_client/health_check_service.rb
index 6c1213f5e20..0c495f60633 100644
--- a/lib/gitlab/gitaly_client/health_check_service.rb
+++ b/lib/gitlab/gitaly_client/health_check_service.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module GitalyClient
     class HealthCheckService
diff --git a/lib/gitlab/gitaly_client/namespace_service.rb b/lib/gitlab/gitaly_client/namespace_service.rb
index d4e982b649a..f0be3cbebd2 100644
--- a/lib/gitlab/gitaly_client/namespace_service.rb
+++ b/lib/gitlab/gitaly_client/namespace_service.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module GitalyClient
     class NamespaceService
diff --git a/lib/gitlab/gitaly_client/notification_service.rb b/lib/gitlab/gitaly_client/notification_service.rb
index 326e6f7dafc..873c3e4086d 100644
--- a/lib/gitlab/gitaly_client/notification_service.rb
+++ b/lib/gitlab/gitaly_client/notification_service.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module GitalyClient
     class NotificationService
diff --git a/lib/gitlab/gitaly_client/operation_service.rb b/lib/gitlab/gitaly_client/operation_service.rb
index 4c78b790ce5..c32c2c0b2fb 100644
--- a/lib/gitlab/gitaly_client/operation_service.rb
+++ b/lib/gitlab/gitaly_client/operation_service.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module GitalyClient
     class OperationService
diff --git a/lib/gitlab/gitaly_client/queue_enumerator.rb b/lib/gitlab/gitaly_client/queue_enumerator.rb
index b8018029552..3a412102abe 100644
--- a/lib/gitlab/gitaly_client/queue_enumerator.rb
+++ b/lib/gitlab/gitaly_client/queue_enumerator.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module GitalyClient
     class QueueEnumerator
diff --git a/lib/gitlab/gitaly_client/ref_service.rb b/lib/gitlab/gitaly_client/ref_service.rb
index 8acc22e809e..d5633d167ac 100644
--- a/lib/gitlab/gitaly_client/ref_service.rb
+++ b/lib/gitlab/gitaly_client/ref_service.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module GitalyClient
     class RefService
@@ -218,7 +220,7 @@ module Gitlab
         request = Gitaly::GetTagMessagesRequest.new(repository: @gitaly_repo, tag_ids: tag_ids)
         response = GitalyClient.call(@repository.storage, :ref_service, :get_tag_messages, request, timeout: GitalyClient.fast_timeout)
 
-        messages = Hash.new { |h, k| h[k] = ''.b }
+        messages = Hash.new { |h, k| h[k] = +''.b }
         current_tag_id = nil
 
         response.each do |rpc_message|
diff --git a/lib/gitlab/gitaly_client/remote_service.rb b/lib/gitlab/gitaly_client/remote_service.rb
index 4661448621b..24e8a5e16d3 100644
--- a/lib/gitlab/gitaly_client/remote_service.rb
+++ b/lib/gitlab/gitaly_client/remote_service.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module GitalyClient
     class RemoteService
diff --git a/lib/gitlab/gitaly_client/repository_service.rb b/lib/gitlab/gitaly_client/repository_service.rb
index d7b36946b65..f968ebc2cbf 100644
--- a/lib/gitlab/gitaly_client/repository_service.rb
+++ b/lib/gitlab/gitaly_client/repository_service.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module GitalyClient
     class RepositoryService
@@ -56,9 +58,9 @@ module Gitlab
         request = Gitaly::GetInfoAttributesRequest.new(repository: @gitaly_repo)
 
         response = GitalyClient.call(@storage, :repository_service, :get_info_attributes, request, timeout: GitalyClient.fast_timeout)
-        response.each_with_object("") do |message, attributes|
+        response.each_with_object([]) do |message, attributes|
           attributes << message.attributes
-        end
+        end.join
       end
 
       def fetch_remote(remote, ssh_auth:, forced:, no_tags:, timeout:, prune: true)
diff --git a/lib/gitlab/gitaly_client/server_service.rb b/lib/gitlab/gitaly_client/server_service.rb
index ad898278353..0ade6942db9 100644
--- a/lib/gitlab/gitaly_client/server_service.rb
+++ b/lib/gitlab/gitaly_client/server_service.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module GitalyClient
     # Meant for extraction of server data, and later maybe to perform misc task
diff --git a/lib/gitlab/gitaly_client/storage_service.rb b/lib/gitlab/gitaly_client/storage_service.rb
index 3a26dd58ff4..4edcb0b8ba9 100644
--- a/lib/gitlab/gitaly_client/storage_service.rb
+++ b/lib/gitlab/gitaly_client/storage_service.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module GitalyClient
     class StorageService
diff --git a/lib/gitlab/gitaly_client/storage_settings.rb b/lib/gitlab/gitaly_client/storage_settings.rb
index 26d1f53f26c..754cccb6b3f 100644
--- a/lib/gitlab/gitaly_client/storage_settings.rb
+++ b/lib/gitlab/gitaly_client/storage_settings.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module GitalyClient
     # This is a chokepoint that is meant to help us stop remove all places
diff --git a/lib/gitlab/gitaly_client/util.rb b/lib/gitlab/gitaly_client/util.rb
index 9c19c51d412..dce5d6a8ad0 100644
--- a/lib/gitlab/gitaly_client/util.rb
+++ b/lib/gitlab/gitaly_client/util.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module GitalyClient
     module Util
diff --git a/lib/gitlab/gitaly_client/wiki_file.rb b/lib/gitlab/gitaly_client/wiki_file.rb
index 47c60c92484..ef2b23732d1 100644
--- a/lib/gitlab/gitaly_client/wiki_file.rb
+++ b/lib/gitlab/gitaly_client/wiki_file.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module GitalyClient
     class WikiFile
diff --git a/lib/gitlab/gitaly_client/wiki_page.rb b/lib/gitlab/gitaly_client/wiki_page.rb
index a02d15db5dd..757a429fb8a 100644
--- a/lib/gitlab/gitaly_client/wiki_page.rb
+++ b/lib/gitlab/gitaly_client/wiki_page.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module Gitlab
   module GitalyClient
     class WikiPage
diff --git a/lib/gitlab/gitaly_client/wiki_service.rb b/lib/gitlab/gitaly_client/wiki_service.rb
index 7c2c228ad01..2b3d622af4d 100644
--- a/lib/gitlab/gitaly_client/wiki_service.rb
+++ b/lib/gitlab/gitaly_client/wiki_service.rb
@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'stringio'
 
 module Gitlab
@@ -139,7 +141,7 @@ module Gitlab
           next unless message.name.present? || wiki_file
 
           if wiki_file
-            wiki_file.raw_data << message.raw_data
+            wiki_file.raw_data = "#{wiki_file.raw_data}#{message.raw_data}"
           else
             wiki_file = GitalyClient::WikiFile.new(message.to_h)
             # All gRPC strings in a response are frozen, so we get
@@ -160,7 +162,7 @@ module Gitlab
         )
 
         response = GitalyClient.call(@repository.storage, :wiki_service, :wiki_get_formatted_data, request)
-        response.reduce("") { |memo, msg| memo << msg.data }
+        response.reduce([]) { |memo, msg| memo << msg.data }.join
       end
 
       private