Use data_source_exists? instead of table_exists?

Use data_source_exists? where possible instead of table_exists? in order to be Rails5 compatible

app/models/project.rb

@@ -72,7 +72,7 @@ class Project < ActiveRecord::Base
 
   add_authentication_token_field :runners_token
 
-  before_validation :mark_remote_mirrors_for_removal, if: -> { ActiveRecord::Base.connection.table_exists?(:remote_mirrors) }
+  before_validation :mark_remote_mirrors_for_removal, if: -> { RemoteMirror.table_exists? }
 
   before_save :ensure_runners_token
 

config/initializers/0_license.rb

@@ -7,7 +7,7 @@ rescue
 end
 
 # Needed to run migration
-if ActiveRecord::Base.connected? && ActiveRecord::Base.connection.table_exists?('licenses')
+if ActiveRecord::Base.connected? && ActiveRecord::Base.connection.data_source_exists?('licenses')
   message = LicenseHelper.license_message(signed_in: true, is_admin: true, in_html: false)
   if ::License.block_changes? && message.present?
     warn "WARNING: #{message}"

config/initializers/active_record_migration.rb

+require 'active_record/migration'
+
+module ActiveRecord
+  class Migration
+    # data_source_exists? is not available in 4.2.10, table_exists deprecated in 5.0
+    def table_exists?(table_name)
+      ActiveRecord::Base.connection.data_source_exists?(table_name)
+    end
+  end
+end

config/initializers/load_balancing.rb

 # We need to run this initializer after migrations are done so it doesn't fail on CI
-if ActiveRecord::Base.connected? && ActiveRecord::Base.connection.table_exists?('licenses')
+if ActiveRecord::Base.connected? && ActiveRecord::Base.connection.data_source_exists?('licenses')
   if Gitlab::Database::LoadBalancing.enable?
     Gitlab::Database.disable_prepared_statements
 

ee/lib/gitlab/geo/health_check.rb

@@ -45,7 +45,7 @@ module Gitlab
           connection = ::Geo::BaseRegistry.connection
           schema_migrations_table_name = ActiveRecord::Base.schema_migrations_table_name
 
-          if connection.table_exists?(schema_migrations_table_name)
+          if connection.data_source_exists?(schema_migrations_table_name)
             connection.execute("SELECT MAX(version) AS version FROM #{schema_migrations_table_name}")
                       .first
                       .fetch('version')

lib/gitlab/background_migration/prepare_untracked_uploads.rb

@@ -54,7 +54,8 @@ module Gitlab
 
       def ensure_temporary_tracking_table_exists
         table_name = :untracked_files_for_uploads
-        unless UntrackedFile.connection.table_exists?(table_name)
+
+        unless ActiveRecord::Base.connection.data_source_exists?(table_name)
           UntrackedFile.connection.create_table table_name do |t|
             t.string :path, limit: 600, null: false
             t.index :path, unique: true

lib/gitlab/database.rb

@@ -226,8 +226,11 @@ module Gitlab
     end
 
     def self.cached_table_exists?(table_name)
-      # Rails 5 uses data_source_exists? instead of table_exists?
-      connection.schema_cache.table_exists?(table_name)
+      if Gitlab.rails5?
+        connection.schema_cache.data_source_exists?(table_name)
+      else
+        connection.schema_cache.table_exists?(table_name)
+      end
     end
 
     private_class_method :connection

spec/lib/gitlab/background_migration/populate_untracked_uploads_spec.rb

@@ -114,7 +114,7 @@ describe Gitlab::BackgroundMigration::PopulateUntrackedUploads, :sidekiq, :migra
     it 'does not drop the temporary tracking table after processing the batch, if there are still untracked rows' do
       subject.perform(1, untracked_files_for_uploads.last.id - 1)
 
-      expect(ActiveRecord::Base.connection.table_exists?(:untracked_files_for_uploads)).to be_truthy
+      expect(ActiveRecord::Base.connection.data_source_exists?(:untracked_files_for_uploads)).to be_truthy
     end
 
     it 'drops the temporary tracking table after processing the batch, if there are no untracked rows left' do

spec/lib/gitlab/database_spec.rb

@@ -400,8 +400,13 @@ describe Gitlab::Database do
 
   describe '.cached_table_exists?' do
     it 'only retrieves data once per table' do
-      expect(ActiveRecord::Base.connection).to receive(:table_exists?).with(:projects).once.and_call_original
-      expect(ActiveRecord::Base.connection).to receive(:table_exists?).with(:bogus_table_name).once.and_call_original
+      if Gitlab.rails5?
+        expect(ActiveRecord::Base.connection).to receive(:data_source_exists?).with(:projects).once.and_call_original
+        expect(ActiveRecord::Base.connection).to receive(:data_source_exists?).with(:bogus_table_name).once.and_call_original
+      else
+        expect(ActiveRecord::Base.connection).to receive(:table_exists?).with(:projects).once.and_call_original
+        expect(ActiveRecord::Base.connection).to receive(:table_exists?).with(:bogus_table_name).once.and_call_original
+      end
 
       2.times do
         expect(described_class.cached_table_exists?(:projects)).to be_truthy

spec/support/helpers/migrations_helpers.rb

@@ -16,10 +16,6 @@ module MigrationsHelpers
     ActiveRecord::Migrator.migrations_paths
   end
 
-  def table_exists?(name)
-    active_record_base.connection.table_exists?(name)
-  end
-
   def migrations
     ActiveRecord::Migrator.migrations(migrations_paths)
   end