Merge branch 'master' of github.com:rails/rails

51 files changed, 393 insertions, 160 deletions

diff --git a/activerecord/lib/active_record/associations/has_many_through_association.rb b/activerecord/lib/active_record/associations/has_many_through_association.rb
index 455a540bdb..bde23fc116 100644
--- a/activerecord/lib/active_record/associations/has_many_through_association.rb
+++ b/activerecord/lib/active_record/associations/has_many_through_association.rb
@@ -1,3 +1,5 @@
+require 'active_support/core_ext/string/filters'
+
 module ActiveRecord
   # = Active Record Has Many Through Association
   module Associations
@@ -63,11 +65,12 @@ module ActiveRecord
 
         save_through_record(record)
         if has_cached_counter? && !through_reflection_updates_counter_cache?
-          ActiveSupport::Deprecation.warn \
-            "Automatic updating of counter caches on through associations has been " \
-            "deprecated, and will be removed in Rails 5.0. Instead, please set the " \
-            "appropriate counter_cache options on the has_many and belongs_to for " \
-            "your associations to #{through_reflection.name}."
+          ActiveSupport::Deprecation.warn(<<-MSG.squish)
+            Automatic updating of counter caches on through associations has been
+            deprecated, and will be removed in Rails 5. Instead, please set the
+            appropriate `counter_cache` options on the `has_many` and `belongs_to`
+            for your associations to #{through_reflection.name}.
+          MSG
 
           update_counter_in_database(1)
         end
@@ -158,8 +161,8 @@ module ActiveRecord
             if scope.klass.primary_key
               count = scope.destroy_all.length
             else
-              scope.to_a.each do |record|
-                record.run_destroy_callbacks
+              scope.each do |record|
+                record._run_destroy_callbacks
               end
 
               arel = scope.arel
diff --git a/activerecord/lib/active_record/associations/preloader/through_association.rb b/activerecord/lib/active_record/associations/preloader/through_association.rb
index d57da366bd..12bf3ef138 100644
--- a/activerecord/lib/active_record/associations/preloader/through_association.rb
+++ b/activerecord/lib/active_record/associations/preloader/through_association.rb
@@ -81,6 +81,7 @@ module ActiveRecord
             unless reflection_scope.where_values.empty?
               scope.includes_values = Array(reflection_scope.values[:includes] || options[:source])
               scope.where_values    = reflection_scope.values[:where]
+              scope.bind_values     = reflection_scope.bind_values
             end
 
             scope.references! reflection_scope.values[:references]
diff --git a/activerecord/lib/active_record/attribute_methods.rb b/activerecord/lib/active_record/attribute_methods.rb
index f4a4e3f605..34ec397aee 100644
--- a/activerecord/lib/active_record/attribute_methods.rb
+++ b/activerecord/lib/active_record/attribute_methods.rb
@@ -1,4 +1,5 @@
 require 'active_support/core_ext/enumerable'
+require 'active_support/core_ext/string/filters'
 require 'mutex_m'
 require 'thread_safe'
 
@@ -90,7 +91,7 @@ module ActiveRecord
 
       def undefine_attribute_methods # :nodoc:
         generated_attribute_methods.synchronize do
-          super if @attribute_methods_generated
+          super if defined?(@attribute_methods_generated) && @attribute_methods_generated
           @attribute_methods_generated = false
         end
       end
@@ -205,9 +206,11 @@ module ActiveRecord
       def column_for_attribute(name)
         column = columns_hash[name.to_s]
         if column.nil?
-          ActiveSupport::Deprecation.warn \
-            "`column_for_attribute` will return a null object for non-existent columns " \
-            "in Rails 5.0. Use `has_attribute?` if you need to check for an attribute's existence."
+          ActiveSupport::Deprecation.warn(<<-MSG.squish)
+            `#column_for_attribute` will return a null object for non-existent
+            columns in Rails 5. Use `#has_attribute?` if you need to check for
+            an attribute's existence.
+          MSG
         end
         column
       end
diff --git a/activerecord/lib/active_record/attribute_methods/serialization.rb b/activerecord/lib/active_record/attribute_methods/serialization.rb
index cc82d00b20..e5ec5ddca5 100644
--- a/activerecord/lib/active_record/attribute_methods/serialization.rb
+++ b/activerecord/lib/active_record/attribute_methods/serialization.rb
@@ -1,3 +1,5 @@
+require 'active_support/core_ext/string/filters'
+
 module ActiveRecord
   module AttributeMethods
     module Serialization
@@ -51,8 +53,10 @@ module ActiveRecord
         end
 
         def serialized_attributes
-          ActiveSupport::Deprecation.warn "`serialized_attributes` is deprecated " \
-            "without replacement, and will be removed in Rails 5.0."
+          ActiveSupport::Deprecation.warn(<<-MSG.squish)
+            `serialized_attributes` is deprecated without replacement, and will
+            be removed in Rails 5.0.
+          MSG
 
           @serialized_attributes ||= Hash[
             columns.select { |t| t.cast_type.is_a?(Type::Serialized) }.map { |c|
diff --git a/activerecord/lib/active_record/attributes.rb b/activerecord/lib/active_record/attributes.rb
index 890a1314d9..3288108a6a 100644
--- a/activerecord/lib/active_record/attributes.rb
+++ b/activerecord/lib/active_record/attributes.rb
@@ -6,7 +6,9 @@ module ActiveRecord
 
     included do
       class_attribute :user_provided_columns, instance_accessor: false # :internal:
+      class_attribute :user_provided_defaults, instance_accessor: false # :internal:
       self.user_provided_columns = {}
+      self.user_provided_defaults = {}
     end
 
     module ClassMethods # :nodoc:
@@ -77,7 +79,11 @@ module ActiveRecord
         name = name.to_s
         clear_caches_calculated_from_columns
         # Assign a new hash to ensure that subclasses do not share a hash
-        self.user_provided_columns = user_provided_columns.merge(name => connection.new_column(name, options[:default], cast_type))
+        self.user_provided_columns = user_provided_columns.merge(name => cast_type)
+
+        if options.key?(:default)
+          self.user_provided_defaults = user_provided_defaults.merge(name => options[:default])
+        end
       end
 
       # Returns an array of column objects for the table associated with this class.
@@ -99,11 +105,18 @@ module ActiveRecord
 
       def add_user_provided_columns(schema_columns)
         existing_columns = schema_columns.map do |column|
-          user_provided_columns[column.name] || column
+          new_type = user_provided_columns[column.name]
+          if new_type
+            column.with_type(new_type)
+          else
+            column
+          end
         end
 
         existing_column_names = existing_columns.map(&:name)
-        new_columns = user_provided_columns.except(*existing_column_names).values
+        new_columns = user_provided_columns.except(*existing_column_names).map do |(name, type)|
+          connection.new_column(name, nil, type)
+        end
 
         existing_columns + new_columns
       end
@@ -117,6 +130,10 @@ module ActiveRecord
         @content_columns = nil
         @default_attributes = nil
       end
+
+      def raw_default_values
+        super.merge(user_provided_defaults)
+      end
     end
   end
 end
diff --git a/activerecord/lib/active_record/callbacks.rb b/activerecord/lib/active_record/callbacks.rb
index 1aa760157a..523d492a48 100644
--- a/activerecord/lib/active_record/callbacks.rb
+++ b/activerecord/lib/active_record/callbacks.rb
@@ -289,25 +289,25 @@ module ActiveRecord
     end
 
     def destroy #:nodoc:
-      run_destroy_callbacks { super }
+      _run_destroy_callbacks { super }
     end
 
     def touch(*) #:nodoc:
-      run_touch_callbacks { super }
+      _run_touch_callbacks { super }
     end
 
   private
 
     def create_or_update #:nodoc:
-      run_save_callbacks { super }
+      _run_save_callbacks { super }
     end
 
     def _create_record #:nodoc:
-      run_create_callbacks { super }
+      _run_create_callbacks { super }
     end
 
     def _update_record(*) #:nodoc:
-      run_update_callbacks { super }
+      _run_update_callbacks { super }
     end
   end
 end
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb b/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb
index da43e5bb10..46812b75bb 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb
@@ -2,6 +2,7 @@ require 'thread'
 require 'thread_safe'
 require 'monitor'
 require 'set'
+require 'active_support/core_ext/string/filters'
 
 module ActiveRecord
   # Raised when a connection could not be obtained within the connection
@@ -360,7 +361,7 @@ module ActiveRecord
         synchronize do
           owner = conn.owner
 
-          conn.run_checkin_callbacks do
+          conn._run_checkin_callbacks do
             conn.expire
           end
 
@@ -449,7 +450,7 @@ module ActiveRecord
       end
 
       def checkout_and_verify(c)
-        c.run_checkout_callbacks do
+        c._run_checkout_callbacks do
           c.verify!
         end
         c
@@ -518,10 +519,11 @@ module ActiveRecord
       end
 
       def connection_pools
-        ActiveSupport::Deprecation.warn(
-          "In the next release, this will return the same as #connection_pool_list. " \
-          "(An array of pools, rather than a hash mapping specs to pools.)"
-        )
+        ActiveSupport::Deprecation.warn(<<-MSG.squish)
+          In the next release, this will return the same as `#connection_pool_list`.
+          (An array of pools, rather than a hash mapping specs to pools.)
+        MSG
+
         Hash[connection_pool_list.map { |pool| [pool.spec, pool] }]
       end
 
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/quoting.rb b/activerecord/lib/active_record/connection_adapters/abstract/quoting.rb
index eb88845913..679878d860 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/quoting.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/quoting.rb
@@ -108,7 +108,7 @@ module ActiveRecord
         when Numeric, ActiveSupport::Duration then value.to_s
         when Date, Time then "'#{quoted_date(value)}'"
         when Symbol     then "'#{quote_string(value.to_s)}'"
-        when Class      then "'#{value.to_s}'"
+        when Class      then "'#{value}'"
         else
           "'#{quote_string(YAML.dump(value))}'"
         end
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb
index adb9fcaeb8..f8b6daea5a 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb
@@ -60,11 +60,11 @@ module ActiveRecord
       def emit_warning_if_null_unspecified(options)
         return if options.key?(:null)
 
-        ActiveSupport::Deprecation.warn \
-          "`timestamp` was called without specifying an option for `null`. In Rails " \
-          "5.0, this behavior will change to `null: false`. You should manually " \
-          "specify `null: true` to prevent the behavior of your existing migrations " \
-          "from changing."
+        ActiveSupport::Deprecation.warn(<<-MSG.squish)
+          `#timestamp` was called without specifying an option for `null`. In Rails 5,
+          this behavior will change to `null: false`. You should manually specify
+         `null: true` to prevent the behavior of your existing migrations from changing.
+        MSG
       end
     end
 
@@ -312,7 +312,7 @@ module ActiveRecord
         args.each do |col|
           column("#{col}_id", type, options)
           column("#{col}_type", :string, polymorphic.is_a?(Hash) ? polymorphic : options) if polymorphic
-          index(polymorphic ? %w(id type).map { |t| "#{col}_#{t}" } : "#{col}_id", index_options.is_a?(Hash) ? index_options : {}) if index_options
+          index(polymorphic ? %w(type id).map { |t| "#{col}_#{t}" } : "#{col}_id", index_options.is_a?(Hash) ? index_options : {}) if index_options
         end
       end
       alias :belongs_to :references
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_dumper.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_dumper.rb
index b05a4f8440..6eab11b88b 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/schema_dumper.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_dumper.rb
@@ -8,7 +8,7 @@ module ActiveRecord
     module ColumnDumper
       def column_spec(column, types)
         spec = prepare_column_options(column, types)
-        (spec.keys - [:name, :type]).each{ |k| spec[k].insert(0, "#{k.to_s}: ")}
+        (spec.keys - [:name, :type]).each{ |k| spec[k].insert(0, "#{k}: ")}
         spec
       end
 
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb
index 7105df1ee4..cbf87df356 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_statements.rb
@@ -629,7 +629,7 @@ module ActiveRecord
         type = options.delete(:type) || :integer
         add_column(table_name, "#{ref_name}_id", type, options)
         add_column(table_name, "#{ref_name}_type", :string, polymorphic.is_a?(Hash) ? polymorphic : options) if polymorphic
-        add_index(table_name, polymorphic ? %w[id type].map{ |t| "#{ref_name}_#{t}" } : "#{ref_name}_id", index_options.is_a?(Hash) ? index_options : {}) if index_options
+        add_index(table_name, polymorphic ? %w[type id].map{ |t| "#{ref_name}_#{t}" } : "#{ref_name}_id", index_options.is_a?(Hash) ? index_options : {}) if index_options
       end
       alias :add_belongs_to :add_reference
 
diff --git a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
index a0d9086875..582dd360f0 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract_adapter.rb
@@ -14,10 +14,7 @@ module ActiveRecord
   module ConnectionAdapters # :nodoc:
     extend ActiveSupport::Autoload
 
-    autoload_at 'active_record/connection_adapters/column' do
-      autoload :Column
-      autoload :NullColumn
-    end
+    autoload :Column
     autoload :ConnectionSpecification
 
     autoload_at 'active_record/connection_adapters/abstract/schema_definitions' do
@@ -267,7 +264,7 @@ module ActiveRecord
 
       # Returns a bind substitution value given a bind +index+ and +column+
       # NOTE: The column param is currently being used by the sqlserver-adapter
-      def substitute_at(column, index)
+      def substitute_at(column, index = 0)
         Arel::Nodes::BindParam.new '?'
       end
 
@@ -386,6 +383,10 @@ module ActiveRecord
         type_map.lookup(sql_type)
       end
 
+      def column_name_for_operation(operation, node) # :nodoc:
+        node.to_sql
+      end
+
       protected
 
       def initialize_type_map(m) # :nodoc:
diff --git a/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb b/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
index e4cfe843a8..7f04e35042 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract_mysql_adapter.rb
@@ -91,6 +91,13 @@ module ActiveRecord
           collation && !collation.match(/_ci$/)
         end
 
+        def ==(other)
+          super &&
+            collation == other.collation &&
+            strict == other.strict &&
+            extra == other.extra
+        end
+
         private
 
         # MySQL misreports NOT NULL column default when none is given.
@@ -109,6 +116,10 @@ module ActiveRecord
             raise ArgumentError, "#{type} columns cannot have a default value: #{default.inspect}"
           end
         end
+
+        def attributes_for_hash
+          super + [collation, strict, extra]
+        end
       end
 
       ##
@@ -485,7 +496,7 @@ module ActiveRecord
         end
       end
 
-      def change_column_default(table_name, column_name, default)
+      def change_column_default(table_name, column_name, default) #:nodoc:
         column = column_for(table_name, column_name)
         change_column table_name, column_name, column.sql_type, :default => default
       end
@@ -645,12 +656,6 @@ module ActiveRecord
       def initialize_type_map(m) # :nodoc:
         super
 
-        m.register_type(%r(enum)i) do |sql_type|
-          limit = sql_type[/^enum\((.+)\)/i, 1]
-            .split(',').map{|enum| enum.strip.length - 2}.max
-          Type::String.new(limit: limit)
-        end
-
         m.register_type %r(tinytext)i,   Type::Text.new(limit: 2**8 - 1)
         m.register_type %r(tinyblob)i,   Type::Binary.new(limit: 2**8 - 1)
         m.register_type %r(text)i,       Type::Text.new(limit: 2**16 - 1)
@@ -671,6 +676,12 @@ module ActiveRecord
         m.alias_type %r(set)i,           'varchar'
         m.alias_type %r(year)i,          'integer'
         m.alias_type %r(bit)i,           'binary'
+
+        m.register_type(%r(enum)i) do |sql_type|
+          limit = sql_type[/^enum\((.+)\)/i, 1]
+            .split(',').map{|enum| enum.strip.length - 2}.max
+          Type::String.new(limit: limit)
+        end
       end
 
       # MySQL is too stupid to create a temporary table for use subquery, so we have
@@ -825,9 +836,9 @@ module ActiveRecord
         # Gather up all of the SET variables...
         variable_assignments = variables.map do |k, v|
           if v == ':default' || v == :default
-            "@@SESSION.#{k.to_s} = DEFAULT" # Sets the value to the global or compile default
+            "@@SESSION.#{k} = DEFAULT" # Sets the value to the global or compile default
           elsif !v.nil?
-            "@@SESSION.#{k.to_s} = #{quote(v)}"
+            "@@SESSION.#{k} = #{quote(v)}"
           end
           # or else nil; compact to clear nils out
         end.compact.join(', ')
diff --git a/activerecord/lib/active_record/connection_adapters/column.rb b/activerecord/lib/active_record/connection_adapters/column.rb
index 5f9cc6edd0..dd303c73d5 100644
--- a/activerecord/lib/active_record/connection_adapters/column.rb
+++ b/activerecord/lib/active_record/connection_adapters/column.rb
@@ -56,6 +56,26 @@ module ActiveRecord
           clone.instance_variable_set('@cast_type', type)
         end
       end
+
+      def ==(other)
+        other.name == name &&
+          other.default == default &&
+          other.cast_type == cast_type &&
+          other.sql_type == sql_type &&
+          other.null == null &&
+          other.default_function == default_function
+      end
+      alias :eql? :==
+
+      def hash
+        attributes_for_hash.hash
+      end
+
+      private
+
+      def attributes_for_hash
+        [self.class, name, default, cast_type, sql_type, null, default_function]
+      end
     end
   end
   # :startdoc:
diff --git a/activerecord/lib/active_record/connection_adapters/connection_specification.rb b/activerecord/lib/active_record/connection_adapters/connection_specification.rb
index e02824b33d..609ec7dabd 100644
--- a/activerecord/lib/active_record/connection_adapters/connection_specification.rb
+++ b/activerecord/lib/active_record/connection_adapters/connection_specification.rb
@@ -1,4 +1,5 @@
 require 'uri'
+require 'active_support/core_ext/string/filters'
 
 module ActiveRecord
   module ConnectionAdapters
@@ -221,8 +222,12 @@ module ActiveRecord
           # this ambiguous behaviour and in the future this function
           # can be removed in favor of resolve_url_connection.
           if configurations.key?(spec) || spec !~ /:/
-            ActiveSupport::Deprecation.warn "Passing a string to ActiveRecord::Base.establish_connection " \
-              "for a configuration lookup is deprecated, please pass a symbol (#{spec.to_sym.inspect}) instead"
+            ActiveSupport::Deprecation.warn(<<-MSG.squish)
+              Passing a string to ActiveRecord::Base.establish_connection for a
+              configuration lookup is deprecated, please pass a symbol
+              (#{spec.to_sym.inspect}) instead.
+            MSG
+
             resolve_symbol_connection(spec)
           else
             resolve_url_connection(spec)
diff --git a/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb b/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb
index cff6798eb3..3357ed52e5 100644
--- a/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/mysql_adapter.rb
@@ -88,7 +88,7 @@ module ActiveRecord
         end
 
         def clear
-          cache.values.each do |hash|
+          cache.each_value do |hash|
             hash[:stmt].close
           end
           cache.clear
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/database_statements.rb b/activerecord/lib/active_record/connection_adapters/postgresql/database_statements.rb
index 89a7257d77..cf379ab210 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/database_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/database_statements.rb
@@ -156,7 +156,7 @@ module ActiveRecord
           end
         end
 
-        def substitute_at(column, index)
+        def substitute_at(column, index = 0)
           Arel::Nodes::BindParam.new "$#{index + 1}"
         end
 
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid/cidr.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid/cidr.rb
index a53b4ee8e2..222f10fa8f 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/oid/cidr.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/oid/cidr.rb
@@ -12,15 +12,15 @@ module ActiveRecord
 
             # If the subnet mask is equal to /32, don't output it
             if subnet_mask == (2**32 - 1)
-              "\"#{value.to_s}\""
+              "\"#{value}\""
             else
-              "\"#{value.to_s}/#{subnet_mask.to_s(2).count('1')}\""
+              "\"#{value}/#{subnet_mask.to_s(2).count('1')}\""
             end
           end
 
           def type_cast_for_database(value)
             if IPAddr === value
-              "#{value.to_s}/#{value.instance_variable_get(:@mask_addr).to_s(2).count('1')}"
+              "#{value}/#{value.instance_variable_get(:@mask_addr).to_s(2).count('1')}"
             else
               value
             end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid/range.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid/range.rb
index 84b9490ba3..961e6224c4 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/oid/range.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/oid/range.rb
@@ -1,3 +1,5 @@
+require 'active_support/core_ext/string/filters'
+
 module ActiveRecord
   module ConnectionAdapters
     module PostgreSQL
@@ -25,10 +27,11 @@ module ActiveRecord
             if !infinity?(from) && extracted[:exclude_start]
               if from.respond_to?(:succ)
                 from = from.succ
-                ActiveSupport::Deprecation.warn \
-                  "Excluding the beginning of a Range is only partialy supported " \
-                  "through `#succ`. This is not reliable and will be removed in " \
-                  "the future."
+                ActiveSupport::Deprecation.warn(<<-MSG.squish)
+                  Excluding the beginning of a Range is only partialy supported
+                  through `#succ`. This is not reliable and will be removed in
+                  the future.
+                MSG
               else
                 raise ArgumentError, "The Ruby Range object does not support excluding the beginning of a Range. (unsupported value: '#{value}')"
               end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb b/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb
index e396ff4a1e..35e699eeda 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/oid/type_map_initializer.rb
@@ -4,7 +4,7 @@ module ActiveRecord
       module OID # :nodoc:
         # This class uses the data from PostgreSQL pg_type table to build
         # the OID -> Type mapping.
-        #   - OID is and integer representing the type.
+        #   - OID is an integer representing the type.
         #   - Type is an OID::Type object.
         # This class has side effects on the +store+ passed during initialization.
         class TypeMapInitializer # :nodoc:
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/quoting.rb b/activerecord/lib/active_record/connection_adapters/postgresql/quoting.rb
index cf5c8d288e..f95f45c689 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/quoting.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/quoting.rb
@@ -21,7 +21,7 @@ module ActiveRecord
           case value
           when Float
             if value.infinite? || value.nan?
-              "'#{value.to_s}'"
+              "'#{value}'"
             else
               super
             end
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb b/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb
index 799aafbd99..51853c6812 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb
@@ -293,6 +293,23 @@ module ActiveRecord
           result.rows.first.first
         end
 
+        # Sets the sequence of a table's primary key to the specified value.
+        def set_pk_sequence!(table, value) #:nodoc:
+          pk, sequence = pk_and_sequence_for(table)
+
+          if pk
+            if sequence
+              quoted_sequence = quote_table_name(sequence)
+
+              select_value <<-end_sql, 'SCHEMA'
+              SELECT setval('#{quoted_sequence}', #{value})
+              end_sql
+            else
+              @logger.warn "#{table} has primary key #{pk} with no default sequence" if @logger
+            end
+          end
+        end
+
         # Resets the sequence of a table's primary key to the maximum value.
         def reset_pk_sequence!(table, pk = nil, sequence = nil) #:nodoc:
           unless pk and sequence
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
index 3294238fa0..e472741660 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
@@ -78,6 +78,7 @@ module ActiveRecord
 
       NATIVE_DATABASE_TYPES = {
         primary_key: "serial primary key",
+        bigserial: "bigserial",
         string:      { name: "character varying" },
         text:        { name: "text" },
         integer:     { name: "integer" },
@@ -392,6 +393,16 @@ module ActiveRecord
         super(oid)
       end
 
+      def column_name_for_operation(operation, node) # :nodoc:
+        OPERATION_ALIASES.fetch(operation) { operation.downcase }
+      end
+
+      OPERATION_ALIASES = { # :nodoc:
+        "maximum" => "max",
+        "minimum" => "min",
+        "average" => "avg",
+      }
+
       protected
 
         # Returns the version of the connected PostgreSQL server.
@@ -678,9 +689,9 @@ module ActiveRecord
           variables.map do |k, v|
             if v == ':default' || v == :default
               # Sets the value to the global or compile default
-              execute("SET SESSION #{k.to_s} TO DEFAULT", 'SCHEMA')
+              execute("SET SESSION #{k} TO DEFAULT", 'SCHEMA')
             elsif !v.nil?
-              execute("SET SESSION #{k.to_s} TO #{quote(v)}", 'SCHEMA')
+              execute("SET SESSION #{k} TO #{quote(v)}", 'SCHEMA')
             end
           end
         end
diff --git a/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb b/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
index 4756896ac5..1b5e3bdbac 100644
--- a/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
@@ -115,7 +115,7 @@ module ActiveRecord
         end
 
         def clear
-          cache.values.each do |hash|
+          cache.each_value do |hash|
             dealloc hash[:stmt]
           end
           cache.clear
diff --git a/activerecord/lib/active_record/connection_handling.rb b/activerecord/lib/active_record/connection_handling.rb
index 31e7390bf7..8f51590c99 100644
--- a/activerecord/lib/active_record/connection_handling.rb
+++ b/activerecord/lib/active_record/connection_handling.rb
@@ -1,6 +1,6 @@
 module ActiveRecord
   module ConnectionHandling
-    RAILS_ENV   = -> { Rails.env if defined?(Rails) }
+    RAILS_ENV   = -> { (Rails.env if defined?(Rails)) || ENV["RAILS_ENV"] || ENV["RACK_ENV"] }
     DEFAULT_ENV = -> { RAILS_ENV.call || "default_env" }
 
     # Establishes the connection to the database. Accepts a hash as input where
diff --git a/activerecord/lib/active_record/core.rb b/activerecord/lib/active_record/core.rb
index 5571a2d297..952aeaa703 100644
--- a/activerecord/lib/active_record/core.rb
+++ b/activerecord/lib/active_record/core.rb
@@ -1,6 +1,7 @@
+require 'thread'
 require 'active_support/core_ext/hash/indifferent_access'
 require 'active_support/core_ext/object/duplicable'
-require 'thread'
+require 'active_support/core_ext/string/filters'
 
 module ActiveRecord
   module Core
@@ -88,8 +89,10 @@ module ActiveRecord
       mattr_accessor :maintain_test_schema, instance_accessor: false
 
       def self.disable_implicit_join_references=(value)
-        ActiveSupport::Deprecation.warn("Implicit join references were removed with Rails 4.1." \
-                                        "Make sure to remove this configuration because it does nothing.")
+        ActiveSupport::Deprecation.warn(<<-MSG.squish)
+          Implicit join references were removed with Rails 4.1.
+          Make sure to remove this configuration because it does nothing.
+        MSG
       end
 
       class_attribute :default_connection_handler, instance_writer: false
@@ -135,8 +138,10 @@ module ActiveRecord
         id  = ids.first
         if ActiveRecord::Base === id
           id = id.id
-          ActiveSupport::Deprecation.warn "You are passing an instance of ActiveRecord::Base to `find`." \
-            "Please pass the id of the object by calling `.id`"
+          ActiveSupport::Deprecation.warn(<<-MSG.squish)
+            You are passing an instance of ActiveRecord::Base to `find`.
+            Please pass the id of the object by calling `.id`
+          MSG
         end
         key = primary_key
 
@@ -150,6 +155,8 @@ module ActiveRecord
           raise RecordNotFound, "Couldn't find #{name} with '#{primary_key}'=#{id}"
         end
         record
+      rescue RangeError
+        raise RecordNotFound, "Couldn't find #{name} with an out of range value for '#{primary_key}'"
       end
 
       def find_by(*args)
@@ -180,6 +187,8 @@ module ActiveRecord
           s.execute(hash.values, self, connection).first
         rescue TypeError => e
           raise ActiveRecord::StatementInvalid.new(e.message, e)
+        rescue RangeError
+          nil
         end
       end
 
@@ -261,7 +270,7 @@ module ActiveRecord
     #   # Instantiates a single new object
     #   User.new(first_name: 'Jamie')
     def initialize(attributes = nil, options = {})
-      @attributes = self.class.default_attributes.dup
+      @attributes = self.class._default_attributes.dup
 
       init_internals
       initialize_internals_callback
@@ -272,7 +281,7 @@ module ActiveRecord
       init_attributes(attributes, options) if attributes
 
       yield self if block_given?
-      run_initialize_callbacks
+      _run_initialize_callbacks
     end
 
     # Initialize an empty model object from +coder+. +coder+ must contain
@@ -294,8 +303,8 @@ module ActiveRecord
 
       self.class.define_attribute_methods
 
-      run_find_callbacks
-      run_initialize_callbacks
+      _run_find_callbacks
+      _run_initialize_callbacks
 
       self
     end
@@ -331,7 +340,7 @@ module ActiveRecord
       @attributes = @attributes.dup
       @attributes.reset(self.class.primary_key)
 
-      run_initialize_callbacks
+      _run_initialize_callbacks
 
       @aggregation_cache = {}
       @association_cache = {}
diff --git a/activerecord/lib/active_record/fixtures.rb b/activerecord/lib/active_record/fixtures.rb
index 125a119b5f..db6421dacb 100644
--- a/activerecord/lib/active_record/fixtures.rb
+++ b/activerecord/lib/active_record/fixtures.rb
@@ -649,7 +649,7 @@ module ActiveRecord
               model_class
             end
 
-          reflection_class._reflections.values.each do |association|
+          reflection_class._reflections.each_value do |association|
             case association.macro
             when :belongs_to
               # Do not replace association name with association foreign key if they are named the same
diff --git a/activerecord/lib/active_record/gem_version.rb b/activerecord/lib/active_record/gem_version.rb
index 91747d2ccf..e820835626 100644
--- a/activerecord/lib/active_record/gem_version.rb
+++ b/activerecord/lib/active_record/gem_version.rb
@@ -8,7 +8,7 @@ module ActiveRecord
     MAJOR = 4
     MINOR = 2
     TINY  = 0
-    PRE   = "beta2"
+    PRE   = "beta4"
 
     STRING = [MAJOR, MINOR, TINY, PRE].compact.join(".")
   end
diff --git a/activerecord/lib/active_record/inheritance.rb b/activerecord/lib/active_record/inheritance.rb
index 251d682a02..f58145ab05 100644
--- a/activerecord/lib/active_record/inheritance.rb
+++ b/activerecord/lib/active_record/inheritance.rb
@@ -80,12 +80,12 @@ module ActiveRecord
       end
 
       def symbolized_base_class
-        ActiveSupport::Deprecation.warn("ActiveRecord::Base.symbolized_base_class is deprecated and will be removed without replacement.")
+        ActiveSupport::Deprecation.warn('`ActiveRecord::Base.symbolized_base_class` is deprecated and will be removed without replacement.')
         @symbolized_base_class ||= base_class.to_s.to_sym
       end
 
       def symbolized_sti_name
-        ActiveSupport::Deprecation.warn("ActiveRecord::Base.symbolized_sti_name is deprecated and will be removed without replacement.")
+        ActiveSupport::Deprecation.warn('`ActiveRecord::Base.symbolized_sti_name` is deprecated and will be removed without replacement.')
         @symbolized_sti_name ||= sti_name.present? ? sti_name.to_sym : symbolized_base_class
       end
 
diff --git a/activerecord/lib/active_record/migration.rb b/activerecord/lib/active_record/migration.rb
index d0d9304a36..2024b225e4 100644
--- a/activerecord/lib/active_record/migration.rb
+++ b/activerecord/lib/active_record/migration.rb
@@ -394,8 +394,8 @@ module ActiveRecord
       end
 
       def load_schema_if_pending!
-        if ActiveRecord::Migrator.needs_migration?
-          ActiveRecord::Tasks::DatabaseTasks.load_schema_current
+        if ActiveRecord::Migrator.needs_migration? || !ActiveRecord::Migrator.any_migrations?
+          ActiveRecord::Tasks::DatabaseTasks.load_schema_current_if_exists
           check_pending!
         end
       end
@@ -848,6 +848,10 @@ module ActiveRecord
         (migrations(migrations_paths).collect(&:version) - get_all_versions(connection)).size > 0
       end
 
+      def any_migrations?
+        migrations(migrations_paths).any?
+      end
+
       def last_version
         last_migration.version
       end
diff --git a/activerecord/lib/active_record/model_schema.rb b/activerecord/lib/active_record/model_schema.rb
index 48e82d28d9..a444aac23c 100644
--- a/activerecord/lib/active_record/model_schema.rb
+++ b/activerecord/lib/active_record/model_schema.rb
@@ -247,12 +247,12 @@ module ActiveRecord
       # Returns a hash where the keys are column names and the values are
       # default values when instantiating the AR object for this table.
       def column_defaults
-        default_attributes.to_hash
+        _default_attributes.to_hash
       end
 
-      def default_attributes # :nodoc:
+      def _default_attributes # :nodoc:
         @default_attributes ||= attributes_builder.build_from_database(
-          columns_hash.transform_values(&:default))
+          raw_default_values)
       end
 
       # Returns an array of column names as strings.
@@ -331,6 +331,10 @@ module ActiveRecord
           base.table_name
         end
       end
+
+      def raw_default_values
+        columns_hash.transform_values(&:default)
+      end
     end
   end
 end
diff --git a/activerecord/lib/active_record/railties/databases.rake b/activerecord/lib/active_record/railties/databases.rake
index 44765bd050..3ec25f9f17 100644
--- a/activerecord/lib/active_record/railties/databases.rake
+++ b/activerecord/lib/active_record/railties/databases.rake
@@ -196,7 +196,8 @@ db_namespace = namespace :db do
       fixture_files = if ENV['FIXTURES']
                         ENV['FIXTURES'].split(',')
                       else
-                        Pathname.glob("#{fixtures_dir}/**/*.yml").map {|f| f.basename.sub_ext('').to_s }
+                        # The use of String#[] here is to support namespaced fixtures
+                        Dir["#{fixtures_dir}/**/*.yml"].map {|f| f[(fixtures_dir.size + 1)..-5] }
                       end
 
       ActiveRecord::FixtureSet.create_fixtures(fixtures_dir, fixture_files)
diff --git a/activerecord/lib/active_record/reflection.rb b/activerecord/lib/active_record/reflection.rb
index 22aa175ce2..4b58f2deb7 100644
--- a/activerecord/lib/active_record/reflection.rb
+++ b/activerecord/lib/active_record/reflection.rb
@@ -1,4 +1,5 @@
 require 'thread'
+require 'active_support/core_ext/string/filters'
 
 module ActiveRecord
   # = Active Record Reflection
@@ -153,8 +154,11 @@ module ActiveRecord
       end
 
       def source_macro
-        ActiveSupport::Deprecation.warn("ActiveRecord::Base.source_macro is deprecated and " \
-          "will be removed without replacement.")
+        ActiveSupport::Deprecation.warn(<<-MSG.squish)
+          ActiveRecord::Base.source_macro is deprecated and will be removed
+          without replacement.
+        MSG
+
         macro
       end
     end
@@ -339,13 +343,14 @@ module ActiveRecord
         return unless scope
 
         if scope.arity > 0
-          ActiveSupport::Deprecation.warn \
-            "The association scope '#{name}' is instance dependent (the scope " \
-            "block takes an argument). Preloading happens before the individual " \
-            "instances are created. This means that there is no instance being " \
-            "passed to the association scope. This will most likely result in " \
-            "broken or incorrect behavior. Joining, Preloading and eager loading " \
-            "of these associations is deprecated and will be removed in the future."
+          ActiveSupport::Deprecation.warn(<<-MSG.squish)
+            The association scope '#{name}' is instance dependent (the scope
+            block takes an argument). Preloading happens before the individual
+            instances are created. This means that there is no instance being
+            passed to the association scope. This will most likely result in
+            broken or incorrect behavior. Joining, Preloading and eager loading
+            of these associations is deprecated and will be removed in the future.
+          MSG
         end
       end
       alias :check_eager_loadable! :check_preloadable!
@@ -746,8 +751,11 @@ module ActiveRecord
 
       # The macro used by the source association
       def source_macro
-        ActiveSupport::Deprecation.warn("ActiveRecord::Base.source_macro is deprecated and " \
-          "will be removed without replacement.")
+        ActiveSupport::Deprecation.warn(<<-MSG.squish)
+          ActiveRecord::Base.source_macro is deprecated and will be removed
+          without replacement.
+        MSG
+
         source_reflection.source_macro
       end
 
diff --git a/activerecord/lib/active_record/relation.rb b/activerecord/lib/active_record/relation.rb
index 7f51e4134d..03bce4f5b7 100644
--- a/activerecord/lib/active_record/relation.rb
+++ b/activerecord/lib/active_record/relation.rb
@@ -79,22 +79,27 @@ module ActiveRecord
         scope.unscope!(where: @klass.inheritance_column)
       end
 
-      um = scope.where(@klass.arel_table[@klass.primary_key].eq(id_was || id)).arel.compile_update(substitutes, @klass.primary_key)
+      relation = scope.where(@klass.primary_key => (id_was || id))
+      bvs = binds + relation.bind_values
+      um = relation
+        .arel
+        .compile_update(substitutes, @klass.primary_key)
+      reorder_bind_params(um.ast, bvs)
 
       @klass.connection.update(
         um,
         'SQL',
-        binds)
+        bvs,
+      )
     end
 
     def substitute_values(values) # :nodoc:
-      substitutes = values.sort_by { |arel_attr,_| arel_attr.name }
-      binds       = substitutes.map do |arel_attr, value|
+      binds = values.map do |arel_attr, value|
         [@klass.columns_hash[arel_attr.name], value]
       end
 
-      substitutes.each_with_index do |tuple, i|
-        tuple[1] = @klass.connection.substitute_at(binds[i][0], i)
+      substitutes = values.each_with_index.map do |(arel_attr, _), i|
+        [arel_attr, @klass.connection.substitute_at(binds[i][0], i)]
       end
 
       [substitutes, binds]
@@ -337,7 +342,7 @@ module ActiveRecord
         stmt.wheres = arel.constraints
       end
 
-      bvs = bind_values + arel.bind_values
+      bvs = arel.bind_values + bind_values
       @klass.connection.update stmt, 'SQL', bvs
     end
 
diff --git a/activerecord/lib/active_record/relation/calculations.rb b/activerecord/lib/active_record/relation/calculations.rb
index eaaa409636..c8ebb41131 100644
--- a/activerecord/lib/active_record/relation/calculations.rb
+++ b/activerecord/lib/active_record/relation/calculations.rb
@@ -254,6 +254,7 @@ module ActiveRecord
         select_value = operation_over_aggregate_column(column, operation, distinct)
 
         column_alias = select_value.alias
+        column_alias ||= @klass.connection.column_name_for_operation(operation, select_value)
         relation.select_values = [select_value]
 
         query_builder = relation.arel
diff --git a/activerecord/lib/active_record/relation/finder_methods.rb b/activerecord/lib/active_record/relation/finder_methods.rb
index c95ec2522b..eacae73ebb 100644
--- a/activerecord/lib/active_record/relation/finder_methods.rb
+++ b/activerecord/lib/active_record/relation/finder_methods.rb
@@ -1,4 +1,5 @@
 require 'active_support/deprecation'
+require 'active_support/core_ext/string/filters'
 
 module ActiveRecord
   module FinderMethods
@@ -81,12 +82,16 @@ module ActiveRecord
     #   Post.find_by "published_at < ?", 2.weeks.ago
     def find_by(*args)
       where(*args).take
+    rescue RangeError
+      nil
     end
 
     # Like <tt>find_by</tt>, except that if no record is found, raises
     # an <tt>ActiveRecord::RecordNotFound</tt> error.
     def find_by!(*args)
       where(*args).take!
+    rescue RangeError
+      raise RecordNotFound, "Couldn't find #{@klass.name} with an out of range value"
     end
 
     # Gives a record (or N records if a parameter is supplied) without any implied
@@ -284,8 +289,10 @@ module ActiveRecord
     def exists?(conditions = :none)
       if Base === conditions
         conditions = conditions.id
-        ActiveSupport::Deprecation.warn "You are passing an instance of ActiveRecord::Base to `exists?`." \
-          "Please pass the id of the object by calling `.id`"
+        ActiveSupport::Deprecation.warn(<<-MSG.squish)
+          You are passing an instance of ActiveRecord::Base to `exists?`.
+          Please pass the id of the object by calling `.id`
+        MSG
       end
 
       return false if !conditions
@@ -430,19 +437,20 @@ module ActiveRecord
       else
         find_some(ids)
       end
+    rescue RangeError
+      raise RecordNotFound, "Couldn't find #{@klass.name} with an out of range ID"
     end
 
     def find_one(id)
       if ActiveRecord::Base === id
         id = id.id
-        ActiveSupport::Deprecation.warn "You are passing an instance of ActiveRecord::Base to `find`." \
-          "Please pass the id of the object by calling `.id`"
+        ActiveSupport::Deprecation.warn(<<-MSG.squish)
+          You are passing an instance of ActiveRecord::Base to `find`.
+          Please pass the id of the object by calling `.id`
+        MSG
       end
 
-      column = columns_hash[primary_key]
-      substitute = connection.substitute_at(column, bind_values.length)
-      relation = where(table[primary_key].eq(substitute))
-      relation.bind_values += [[column, id]]
+      relation = where(primary_key => id)
       record = relation.take
 
       raise_record_not_found_exception!(id, 0, 1) unless record
@@ -451,7 +459,7 @@ module ActiveRecord
     end
 
     def find_some(ids)
-      result = where(table[primary_key].in(ids)).to_a
+      result = where(primary_key => ids).to_a
 
       expected_size =
         if limit_value && ids.size > limit_value
diff --git a/activerecord/lib/active_record/relation/merger.rb b/activerecord/lib/active_record/relation/merger.rb
index 545bf5debc..a8febf6a18 100644
--- a/activerecord/lib/active_record/relation/merger.rb
+++ b/activerecord/lib/active_record/relation/merger.rb
@@ -83,12 +83,12 @@ module ActiveRecord
       private
 
       def merge_joins
-        return if values[:joins].blank?
+        return if other.joins_values.blank?
 
         if other.klass == relation.klass
-          relation.joins!(*values[:joins])
+          relation.joins!(*other.joins_values)
         else
-          joins_dependency, rest = values[:joins].partition do |join|
+          joins_dependency, rest = other.joins_values.partition do |join|
             case join
             when Hash, Symbol, Array
               true
@@ -108,10 +108,10 @@ module ActiveRecord
 
       def merge_multi_values
         lhs_wheres = relation.where_values
-        rhs_wheres = values[:where] || []
+        rhs_wheres = other.where_values
 
         lhs_binds  = relation.bind_values
-        rhs_binds  = values[:bind] || []
+        rhs_binds  = other.bind_values
 
         removed, kept = partition_overwrites(lhs_wheres, rhs_wheres)
 
@@ -133,23 +133,23 @@ module ActiveRecord
         relation.where_values = where_values
         relation.bind_values  = bind_values
 
-        if values[:reordering]
+        if other.reordering_value
           # override any order specified in the original relation
-          relation.reorder! values[:order]
-        elsif values[:order]
+          relation.reorder! other.order_values
+        elsif other.order_values
           # merge in order_values from relation
-          relation.order! values[:order]
+          relation.order! other.order_values
         end
 
-        relation.extend(*values[:extending]) unless values[:extending].blank?
+        relation.extend(*other.extending_values) unless other.extending_values.blank?
       end
 
       def merge_single_values
-        relation.from_value          = values[:from] unless relation.from_value
-        relation.lock_value          = values[:lock] unless relation.lock_value
+        relation.from_value          = other.from_value unless relation.from_value
+        relation.lock_value          = other.lock_value unless relation.lock_value
 
-        unless values[:create_with].blank?
-          relation.create_with_value = (relation.create_with_value || {}).merge(values[:create_with])
+        unless other.create_with_value.blank?
+          relation.create_with_value = (relation.create_with_value || {}).merge(other.create_with_value)
         end
       end
 
diff --git a/activerecord/lib/active_record/relation/predicate_builder.rb b/activerecord/lib/active_record/relation/predicate_builder.rb
index 3df0df40ee..e4b6b49087 100644
--- a/activerecord/lib/active_record/relation/predicate_builder.rb
+++ b/activerecord/lib/active_record/relation/predicate_builder.rb
@@ -109,7 +109,7 @@ module ActiveRecord
     # FIXME: I think we need to deprecate this behavior
     register_handler(Class, ->(attribute, value) { attribute.eq(value.name) })
     register_handler(Base, ->(attribute, value) { attribute.eq(value.id) })
-    register_handler(Range, ->(attribute, value) { attribute.in(value) })
+    register_handler(Range, ->(attribute, value) { attribute.between(value) })
     register_handler(Relation, RelationHandler.new)
     register_handler(Array, ArrayHandler.new)
 
diff --git a/activerecord/lib/active_record/relation/predicate_builder/array_handler.rb b/activerecord/lib/active_record/relation/predicate_builder/array_handler.rb
index b8d9240bf8..b8f3285c3e 100644
--- a/activerecord/lib/active_record/relation/predicate_builder/array_handler.rb
+++ b/activerecord/lib/active_record/relation/predicate_builder/array_handler.rb
@@ -1,3 +1,5 @@
+require 'active_support/core_ext/string/filters'
+
 module ActiveRecord
   class PredicateBuilder
     class ArrayHandler # :nodoc:
@@ -6,9 +8,12 @@ module ActiveRecord
         nils, values = values.partition(&:nil?)
 
         if values.any? { |val| val.is_a?(Array) }
-          ActiveSupport::Deprecation.warn "Passing a nested array to Active Record " \
-            "finder methods is deprecated and will be removed. Flatten your array " \
-            "before using it for 'IN' conditions."
+          ActiveSupport::Deprecation.warn(<<-MSG.squish)
+            Passing a nested array to Active Record finder methods is
+            deprecated and will be removed. Flatten your array before using
+            it for 'IN' conditions.
+          MSG
+
           values = values.flatten
         end
 
@@ -27,7 +32,7 @@ module ActiveRecord
           values_predicate = values_predicate.or(attribute.eq(nil))
         end
 
-        array_predicates = ranges.map { |range| attribute.in(range) }
+        array_predicates = ranges.map { |range| attribute.between(range) }
         array_predicates.unshift(values_predicate)
         array_predicates.inject { |composite, predicate| composite.or(predicate) }
       end
diff --git a/activerecord/lib/active_record/relation/predicate_builder/relation_handler.rb b/activerecord/lib/active_record/relation/predicate_builder/relation_handler.rb
index 618fa3cdd9..063150958a 100644
--- a/activerecord/lib/active_record/relation/predicate_builder/relation_handler.rb
+++ b/activerecord/lib/active_record/relation/predicate_builder/relation_handler.rb
@@ -6,7 +6,7 @@ module ActiveRecord
           value = value.select(value.klass.arel_table[value.klass.primary_key])
         end
 
-        attribute.in(value.arel.ast)
+        attribute.in(value.arel)
       end
     end
   end
diff --git a/activerecord/lib/active_record/relation/query_methods.rb b/activerecord/lib/active_record/relation/query_methods.rb
index bbddd28ccc..a686e3263b 100644
--- a/activerecord/lib/active_record/relation/query_methods.rb
+++ b/activerecord/lib/active_record/relation/query_methods.rb
@@ -1,4 +1,5 @@
 require 'active_support/core_ext/array/wrap'
+require 'active_support/core_ext/string/filters'
 require 'active_model/forbidden_attributes_protection'
 
 module ActiveRecord
@@ -94,8 +95,10 @@ module ActiveRecord
     def check_cached_relation # :nodoc:
       if defined?(@arel) && @arel
         @arel = nil
-        ActiveSupport::Deprecation.warn "Modifying already cached Relation. The " \
-          "cache will be reset. Use a cloned Relation to prevent this warning."
+        ActiveSupport::Deprecation.warn(<<-MSG.squish)
+          Modifying already cached Relation. The cache will be reset. Use a
+          cloned Relation to prevent this warning.
+        MSG
       end
     end
 
@@ -436,7 +439,7 @@ module ActiveRecord
       self
     end
 
-    def bind(value)
+    def bind(value) # :nodoc:
       spawn.bind!(value)
     end
 
@@ -880,12 +883,15 @@ module ActiveRecord
 
       # Reorder bind indexes if joins produced bind values
       bvs = arel.bind_values + bind_values
-      arel.ast.grep(Arel::Nodes::BindParam).each_with_index do |bp, i|
+      reorder_bind_params(arel.ast, bvs)
+      arel
+    end
+
+    def reorder_bind_params(ast, bvs)
+      ast.grep(Arel::Nodes::BindParam).each_with_index do |bp, i|
         column = bvs[i].first
         bp.replace connection.substitute_at(column, i)
       end
-
-      arel
     end
 
     def symbol_unscoping(scope)
@@ -913,7 +919,7 @@ module ActiveRecord
 
       where_values.reject! do |rel|
         case rel
-        when Arel::Nodes::In, Arel::Nodes::NotIn, Arel::Nodes::Equality, Arel::Nodes::NotEqual
+        when Arel::Nodes::Between, Arel::Nodes::In, Arel::Nodes::NotIn, Arel::Nodes::Equality, Arel::Nodes::NotEqual, Arel::Nodes::LessThanOrEqual, Arel::Nodes::GreaterThanOrEqual
           subrelation = (rel.left.kind_of?(Arel::Attributes::Attribute) ? rel.left : rel.right)
           subrelation.name == target_value
         end
@@ -955,8 +961,7 @@ module ActiveRecord
       when Hash
         opts = PredicateBuilder.resolve_column_aliases(klass, opts)
 
-        bv_len = bind_values.length
-        tmp_opts, bind_values = create_binds(opts, bv_len)
+        tmp_opts, bind_values = create_binds(opts)
         self.bind_values += bind_values
 
         attributes = @klass.send(:expand_hash_conditions_for_aggregates, tmp_opts)
@@ -968,7 +973,7 @@ module ActiveRecord
       end
     end
 
-    def create_binds(opts, idx)
+    def create_binds(opts)
       bindable, non_binds = opts.partition do |column, value|
         case value
         when String, Integer, ActiveRecord::StatementCache::Substitute
@@ -978,12 +983,23 @@ module ActiveRecord
         end
       end
 
+      association_binds, non_binds = non_binds.partition do |column, value|
+        value.is_a?(Hash) && association_for_table(column)
+      end
+
       new_opts = {}
       binds = []
 
-      bindable.each_with_index do |(column,value), index|
+      bindable.each do |(column,value)|
         binds.push [@klass.columns_hash[column.to_s], value]
-        new_opts[column] = connection.substitute_at(column, index + idx)
+        new_opts[column] = connection.substitute_at(column)
+      end
+
+      association_binds.each do |(column, value)|
+        association_relation = association_for_table(column).klass.send(:relation)
+        association_new_opts, association_bind = association_relation.send(:create_binds, value)
+        new_opts[column] = association_new_opts
+        binds += association_bind
       end
 
       non_binds.each { |column,value| new_opts[column] = value }
@@ -991,6 +1007,12 @@ module ActiveRecord
       [new_opts, binds]
     end
 
+    def association_for_table(table_name)
+      table_name = table_name.to_s
+      @klass._reflect_on_association(table_name) ||
+        @klass._reflect_on_association(table_name.singularize)
+    end
+
     def build_from
       opts, name = from_value
       case opts
diff --git a/activerecord/lib/active_record/sanitization.rb b/activerecord/lib/active_record/sanitization.rb
index ff70cbed0f..6a130c145b 100644
--- a/activerecord/lib/active_record/sanitization.rb
+++ b/activerecord/lib/active_record/sanitization.rb
@@ -87,6 +87,9 @@ module ActiveRecord
       #   { address: Address.new("123 abc st.", "chicago") }
       #     # => "address_street='123 abc st.' and address_city='chicago'"
       def sanitize_sql_hash_for_conditions(attrs, default_table_name = self.table_name)
+        ActiveSupport::Deprecation.warn(<<-EOWARN)
+sanitize_sql_hash_for_conditions is deprecated, and will be removed in Rails 5.0
+        EOWARN
         attrs = PredicateBuilder.resolve_column_aliases self, attrs
         attrs = expand_hash_conditions_for_aggregates(attrs)
 
@@ -134,7 +137,7 @@ module ActiveRecord
         raise_if_bind_arity_mismatch(statement, statement.count('?'), values.size)
         bound = values.dup
         c = connection
-        statement.gsub('?') do
+        statement.gsub(/\?/) do
           replace_bind_variable(bound.shift, c)
         end
       end
diff --git a/activerecord/lib/active_record/schema_dumper.rb b/activerecord/lib/active_record/schema_dumper.rb
index 82c5ca291c..261fb9d992 100644
--- a/activerecord/lib/active_record/schema_dumper.rb
+++ b/activerecord/lib/active_record/schema_dumper.rb
@@ -118,6 +118,8 @@ HEADER
           if pkcol
             if pk != 'id'
               tbl.print %Q(, primary_key: "#{pk}")
+            elsif pkcol.sql_type == 'bigint'
+              tbl.print ", id: :bigserial"
             elsif pkcol.sql_type == 'uuid'
               tbl.print ", id: :uuid"
               tbl.print %Q(, default: "#{pkcol.default_function}") if pkcol.default_function
diff --git a/activerecord/lib/active_record/scoping/named.rb b/activerecord/lib/active_record/scoping/named.rb
index 49cadb66d0..ec1edf0e01 100644
--- a/activerecord/lib/active_record/scoping/named.rb
+++ b/activerecord/lib/active_record/scoping/named.rb
@@ -139,6 +139,10 @@ module ActiveRecord
         #   Article.published.featured.latest_article
         #   Article.featured.titles
         def scope(name, body, &block)
+          unless body.respond_to?:call
+            raise ArgumentError, 'The scope body needs to be callable.'
+          end
+
           if dangerous_class_method?(name)
             raise ArgumentError, "You tried to define a scope named \"#{name}\" " \
               "on the model \"#{self.name}\", but Active Record already defined " \
diff --git a/activerecord/lib/active_record/tasks/database_tasks.rb b/activerecord/lib/active_record/tasks/database_tasks.rb
index f9b54139d5..1228de2bfd 100644
--- a/activerecord/lib/active_record/tasks/database_tasks.rb
+++ b/activerecord/lib/active_record/tasks/database_tasks.rb
@@ -1,3 +1,5 @@
+require 'active_support/core_ext/string/filters'
+
 module ActiveRecord
   module Tasks # :nodoc:
     class DatabaseAlreadyExists < StandardError; end # :nodoc:
@@ -187,25 +189,35 @@ module ActiveRecord
       end
 
       def load_schema(format = ActiveRecord::Base.schema_format, file = nil)
-        ActiveSupport::Deprecation.warn \
-          "This method will act on a specific connection in the future. " \
-          "To act on the current connection, use `load_schema_current` instead."
+        ActiveSupport::Deprecation.warn(<<-MSG.squish)
+          This method will act on a specific connection in the future.
+          To act on the current connection, use `load_schema_current` instead.
+        MSG
 
         load_schema_current(format, file)
       end
 
+      def schema_file(format = ActiveSupport::Base.schema_format)
+        case format
+        when :ruby
+          File.join(db_dir, "schema.rb")
+        when :sql
+          File.join(db_dir, "structure.sql")
+        end
+      end
+
       # This method is the successor of +load_schema+. We should rename it
       # after +load_schema+ went through a deprecation cycle. (Rails > 4.2)
       def load_schema_for(configuration, format = ActiveRecord::Base.schema_format, file = nil) # :nodoc:
+        file ||= schema_file(format)
+
         case format
         when :ruby
-          file ||= File.join(db_dir, "schema.rb")
           check_schema_file(file)
           purge(configuration)
           ActiveRecord::Base.establish_connection(configuration)
           load(file)
         when :sql
-          file ||= File.join(db_dir, "structure.sql")
           check_schema_file(file)
           purge(configuration)
           structure_load(configuration, file)
@@ -214,6 +226,12 @@ module ActiveRecord
         end
       end
 
+      def load_schema_current_if_exists(format = ActiveRecord::Base.schema_format, file = nil, environment = env)
+        if File.exist?(file || schema_file(format))
+          load_schema_current(format, file, environment)
+        end
+      end
+
       def load_schema_current(format = ActiveRecord::Base.schema_format, file = nil, environment = env)
         each_current_configuration(environment) { |configuration|
           load_schema_for configuration, format, file
diff --git a/activerecord/lib/active_record/transactions.rb b/activerecord/lib/active_record/transactions.rb
index bb06d0304b..f92e1de03b 100644
--- a/activerecord/lib/active_record/transactions.rb
+++ b/activerecord/lib/active_record/transactions.rb
@@ -309,7 +309,7 @@ module ActiveRecord
     # Ensure that it is not called if the object was never persisted (failed create),
     # but call it after the commit of a destroyed object.
     def committed!(should_run_callbacks = true) #:nodoc:
-      run_commit_callbacks if should_run_callbacks && destroyed? || persisted?
+      _run_commit_callbacks if should_run_callbacks && destroyed? || persisted?
     ensure
       force_clear_transaction_record_state
     end
@@ -317,7 +317,7 @@ module ActiveRecord
     # Call the +after_rollback+ callbacks. The +force_restore_state+ argument indicates if the record
     # state should be rolled back to the beginning or just to the last savepoint.
     def rolledback!(force_restore_state = false, should_run_callbacks = true) #:nodoc:
-      run_rollback_callbacks if should_run_callbacks
+      _run_rollback_callbacks if should_run_callbacks
     ensure
       restore_transaction_record_state(force_restore_state)
       clear_transaction_record_state
diff --git a/activerecord/lib/active_record/type.rb b/activerecord/lib/active_record/type.rb
index e3d6c5957e..e5acbbb6b3 100644
--- a/activerecord/lib/active_record/type.rb
+++ b/activerecord/lib/active_record/type.rb
@@ -4,6 +4,7 @@ require 'active_record/type/numeric'
 require 'active_record/type/time_value'
 require 'active_record/type/value'
 
+require 'active_record/type/big_integer'
 require 'active_record/type/binary'
 require 'active_record/type/boolean'
 require 'active_record/type/date'
diff --git a/activerecord/lib/active_record/type/big_integer.rb b/activerecord/lib/active_record/type/big_integer.rb
new file mode 100644
index 0000000000..0c72d8914f
--- /dev/null
+++ b/activerecord/lib/active_record/type/big_integer.rb
@@ -0,0 +1,13 @@
+require 'active_record/type/integer'
+
+module ActiveRecord
+  module Type
+    class BigInteger < Integer # :nodoc:
+      private
+
+      def max_value
+        ::Float::INFINITY
+      end
+    end
+  end
+end
diff --git a/activerecord/lib/active_record/type/boolean.rb b/activerecord/lib/active_record/type/boolean.rb
index 1311be3944..978d16d524 100644
--- a/activerecord/lib/active_record/type/boolean.rb
+++ b/activerecord/lib/active_record/type/boolean.rb
@@ -14,9 +14,13 @@ module ActiveRecord
           true
         else
           if !ConnectionAdapters::Column::FALSE_VALUES.include?(value)
-            ActiveSupport::Deprecation.warn(<<-EOM)
-              You attempted to assign a value which is not explicitly true or false to a boolean column. Currently this value casts to false. This will change to match Ruby's sematics, and will cast to true in Rails 5.0. If you would like to maintain the current behavior, you should explicitly handle the values you would like cast to false.
-            EOM
+            ActiveSupport::Deprecation.warn(<<-MSG.squish)
+              You attempted to assign a value which is not explicitly `true` or `false`
+              to a boolean column. Currently this value casts to `false`. This will
+              change to match Ruby's semantics, and will cast to `true` in Rails 5.
+              If you would like to maintain the current behavior, you should
+              explicitly handle the values you would like cast to `false`.
+            MSG
           end
           false
         end
diff --git a/activerecord/lib/active_record/type/decimal_without_scale.rb b/activerecord/lib/active_record/type/decimal_without_scale.rb
index cabdcecdd7..ff5559e300 100644
--- a/activerecord/lib/active_record/type/decimal_without_scale.rb
+++ b/activerecord/lib/active_record/type/decimal_without_scale.rb
@@ -1,8 +1,8 @@
-require 'active_record/type/integer'
+require 'active_record/type/big_integer'
 
 module ActiveRecord
   module Type
-    class DecimalWithoutScale < Integer # :nodoc:
+    class DecimalWithoutScale < BigInteger # :nodoc:
       def type
         :decimal
       end
diff --git a/activerecord/lib/active_record/type/integer.rb b/activerecord/lib/active_record/type/integer.rb
index 08477d1303..d69e5b3f28 100644
--- a/activerecord/lib/active_record/type/integer.rb
+++ b/activerecord/lib/active_record/type/integer.rb
@@ -3,21 +3,44 @@ module ActiveRecord
     class Integer < Value # :nodoc:
       include Numeric
 
+      def initialize(*)
+        super
+        @range = -max_value...max_value
+      end
+
       def type
         :integer
       end
 
       alias type_cast_for_database type_cast
 
+      protected
+
+      attr_reader :range
+
       private
 
       def cast_value(value)
         case value
         when true then 1
         when false then 0
-        else value.to_i rescue nil
+        else
+          result = value.to_i rescue nil
+          ensure_in_range(result) if result
+          result
         end
       end
+
+      def ensure_in_range(value)
+        unless range.cover?(value)
+          raise RangeError, "#{value} is too large for #{self.class} with limit #{limit || 4}"
+        end
+      end
+
+      def max_value
+        limit = self.limit || 4
+        1 << (limit * 8 - 1) # 8 bits per byte with one bit for sign
+      end
     end
   end
 end