Add frozen string literal to production code

Allows to slightly reduce memory usage.

In the benchmark sample, there is a reduction on Ruby 3.2 from:

    Total allocated: 685520 bytes (4936 objects)

to:

    Total allocated: 660144 bytes (4502 objects)

lib/active_record/connection_adapters/chronomodel_adapter.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'chrono_model'
 
 module ActiveRecord

lib/active_record/tasks/chronomodel_database_tasks.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ActiveRecord
   module Tasks
     class ChronomodelDatabaseTasks < PostgreSQLDatabaseTasks

lib/chrono_model.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'active_record'
 
 require 'chrono_model/conversions'

lib/chrono_model/adapter.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'active_record/connection_adapters/postgresql_adapter'
 
 require 'chrono_model/adapter/migrations'
@@ -84,7 +86,7 @@ def column_definitions; end
     define_method(:column_definitions) do |table_name|
       return super(table_name) unless is_chrono?(table_name)
 
-      on_schema(TEMPORAL_SCHEMA + ',' + self.schema_search_path, recurse: :ignore) { super(table_name) }
+      on_schema("#{TEMPORAL_SCHEMA},#{self.schema_search_path}", recurse: :ignore) { super(table_name) }
     end
 
     # Evaluates the given block in the temporal schema.

lib/chrono_model/adapter/ddl.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'active_support/core_ext/string/strip'
 require 'multi_json'
 

lib/chrono_model/adapter/indexes.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ChronoModel
   class Adapter < ActiveRecord::ConnectionAdapters::PostgreSQLAdapter
     module Indexes

lib/chrono_model/adapter/migrations.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ChronoModel
   class Adapter < ActiveRecord::ConnectionAdapters::PostgreSQLAdapter
     module Migrations

lib/chrono_model/adapter/migrations_modules/legacy.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ChronoModel
   class Adapter
     module MigrationsModules

lib/chrono_model/adapter/migrations_modules/stable.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ChronoModel
   class Adapter
     module MigrationsModules

lib/chrono_model/adapter/tsrange.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ChronoModel
   class Adapter < ActiveRecord::ConnectionAdapters::PostgreSQLAdapter
     module TSRange

lib/chrono_model/adapter/upgrade.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ChronoModel
   class Adapter < ActiveRecord::ConnectionAdapters::PostgreSQLAdapter
     module Upgrade

lib/chrono_model/conversions.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ChronoModel
   module Conversions
     extend self

lib/chrono_model/json.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ChronoModel
   module Json
     extend self

lib/chrono_model/patches.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'chrono_model/patches/as_of_time_holder'
 require 'chrono_model/patches/as_of_time_relation'
 

lib/chrono_model/patches/as_of_time_holder.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ChronoModel
   module Patches
     # Added to classes that need to carry the As-Of date around

lib/chrono_model/patches/as_of_time_relation.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ChronoModel
   module Patches
     # This class is a dummy relation whose scope is only to pass around the

lib/chrono_model/patches/association.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ChronoModel
   module Patches
     # Patches ActiveRecord::Associations::Association to add support for

lib/chrono_model/patches/batches.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ChronoModel
   module Patches
     module Batches

lib/chrono_model/patches/join_node.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ChronoModel
   module Patches
     # This class supports the AR 5.0 code that expects to receive an

lib/chrono_model/patches/preloader.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ChronoModel
   module Patches
     # Patches ActiveRecord::Associations::Preloader to add support for

lib/chrono_model/patches/relation.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ChronoModel
   module Patches
     module Relation

lib/chrono_model/time_gate.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ChronoModel
   # Provides the TimeMachine API to non-temporal models that associate
   # temporal ones.

lib/chrono_model/time_machine.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 require 'chrono_model/time_machine/time_query'
 require 'chrono_model/time_machine/timeline'
 require 'chrono_model/time_machine/history_model'

lib/chrono_model/time_machine/history_model.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ChronoModel
   module TimeMachine
     module HistoryModel
@@ -126,7 +128,7 @@ def descends_from_active_record?
         # current class or a descendant (or self).
         #
         def find_sti_class(type_name)
-          super(type_name + "::History")
+          super("#{type_name}::History")
         end
       end
 

lib/chrono_model/time_machine/time_query.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ChronoModel
   module TimeMachine
     #

lib/chrono_model/time_machine/timeline.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ChronoModel
   module TimeMachine
     module Timeline
@@ -35,12 +37,12 @@ def timeline(record = nil, options = {})
         end
 
         relation = relation
-                   .order('ts ' << (options[:reverse] ? 'DESC' : 'ASC'))
+                   .order("ts #{options[:reverse] ? 'DESC' : 'ASC'}")
 
         relation = relation.from(%["public".#{quoted_table_name}]) unless self.chrono?
         relation = relation.where(id: rid) if rid
 
-        sql = "SELECT ts FROM ( #{relation.to_sql} ) AS foo WHERE ts IS NOT NULL"
+        sql = +"SELECT ts FROM ( #{relation.to_sql} ) AS foo WHERE ts IS NOT NULL"
 
         if options.key?(:before)
           sql << " AND ts < '#{Conversions.time_to_utc_string(options[:before])}'"

lib/chrono_model/utilities.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ChronoModel
   module Utilities
     # Amends the given history item setting a different period.

lib/chrono_model/version.rb

@@ -1,3 +1,5 @@
+# frozen_string_literal: true
+
 module ChronoModel
   VERSION = "1.2.2"
 end