Bring abstract_controller up to date with rails/master

Resolved all the conflicts since 2.3.0 -> HEAD. Following is a list
of commits that could not be applied cleanly or are obviated with the
abstract_controller refactor. They all need to be revisited to ensure
that fixes made in 2.3 do not reappear in 3.0:

2259ecf368e6a6715966f69216e3ee86bf1a82a7
AR not available
  * This will be reimplemented with ActionORM or equivalent

06182ea02e92afad579998aa80144588e8865ac3
implicitly rendering a js response should not use the default layout
[#1844 state:resolved]
  * This will be handled generically

893e9eb99504705419ad6edac14d00e71cef5f12
Improve view rendering performance in development mode and reinstate
template recompiling in production [#1909 state:resolved]
  * We will need to reimplement rails-dev-boost on top of the refactor;
    the changes here are very implementation specific and cannot be
    cleanly applied. The following commits are implicated:

      199e750d46c04970b5e7684998d09405648ecbd4
      3942cb406e1d5db0ac00e03153809cc8dc4cc4db
      f8ea9f85d4f1e3e6f3b5d895bef6b013aa4b0690
      e3b166aab37ddc2fbab030b146eb61713b91bf55
      ae9f258e03c9fd5088da12c1c6cd216cc89a01f7
      44423126c6f6133a1d9cf1d0832b527e8711d40f

0cb020b4d6d838025859bd60fb8151c8e21b8e84
workaround for picking layouts based on wrong view_paths
[#1974 state:resolved]
  * The specifics of this commit no longer apply. Since it is a two-line
    commit, we will reimplement this change.

8c5cc66a831aadb159f3daaffa4208064c30af0e
make action_controller/layouts pick templates from the current instance's
view_paths instead of the class view_paths [#1974 state:resolved]
  * This does not apply at all. It should be trivial to apply the feature
    to the reimplemented ActionController::Base.

87e8b162463f13bd50d27398f020769460a770e3
fix HTML fallback for explicit templates [#2052 state:resolved]
  * There were a number of patches related to this that simply compounded
    each other. Basically none of them apply cleanly, and the underlying
    issue needs to be revisited. After discussing the underlying problem
    with Koz, we will defer these fixes for further discussion.

5 files changed, 88 insertions, 26 deletions

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 901b17124c..aac84cc5f4 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/connection_pool.rb
@@ -351,5 +351,21 @@ module ActiveRecord
         retrieve_connection_pool klass.superclass
       end
     end
+
+    class ConnectionManagement
+      def initialize(app)
+        @app = app
+      end
+
+      def call(env)
+        @app.call(env)
+      ensure
+        # Don't return connection (and peform implicit rollback) if
+        # this request is a part of integration test
+        unless env.key?("rack.test")
+          ActiveRecord::Base.clear_active_connections!
+        end
+      end
+    end
   end
 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 273f823e7f..24c734cddb 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_definitions.rb
@@ -8,6 +8,7 @@ module ActiveRecord
     # An abstract definition of a column in a table.
     class Column
       TRUE_VALUES = [true, 1, '1', 't', 'T', 'true', 'TRUE'].to_set
+      FALSE_VALUES = [false, 0, '0', 'f', 'F', 'false', 'FALSE'].to_set
 
       module Format
         ISO_DATE = /\A(\d{4})-(\d\d)-(\d\d)\z/
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
index 913bb521ca..ec204d0f03 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
@@ -392,9 +392,28 @@ module ActiveRecord
         quote_string(s)
       end
 
+      # Checks the following cases:
+      #
+      # - table_name
+      # - "table.name"
+      # - schema_name.table_name
+      # - schema_name."table.name"
+      # - "schema.name".table_name
+      # - "schema.name"."table.name"
+      def quote_table_name(name)
+        schema, name_part = extract_pg_identifier_from_name(name.to_s)
+
+        unless name_part
+          quote_column_name(schema)
+        else
+          table_name, name_part = extract_pg_identifier_from_name(name_part)
+          "#{quote_column_name(schema)}.#{quote_column_name(table_name)}"
+        end
+      end
+
       # Quotes column names for use in SQL queries.
       def quote_column_name(name) #:nodoc:
-        %("#{name}")
+        PGconn.quote_ident(name.to_s)
       end
 
       # Quote date/time values for use in SQL input. Includes microseconds
@@ -1045,6 +1064,16 @@ module ActiveRecord
              ORDER BY a.attnum
           end_sql
         end
+
+        def extract_pg_identifier_from_name(name)
+          match_data = name[0,1] == '"' ? name.match(/\"([^\"]+)\"/) : name.match(/([^\.]+)/)
+
+          if match_data
+            rest = name[match_data[0].length..-1]
+            rest = rest[1..-1] if rest[0,1] == "."
+            [match_data[1], (rest.length > 0 ? rest : nil)]
+          end
+        end
     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 cc9c46505f..75420f69aa 100644
--- a/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
@@ -18,7 +18,7 @@ module ActiveRecord
 
       db.busy_timeout(config[:timeout]) unless config[:timeout].nil?
 
-      ConnectionAdapters::SQLite3Adapter.new(db, logger)
+      ConnectionAdapters::SQLite3Adapter.new(db, logger, config)
     end
   end
 
diff --git a/activerecord/lib/active_record/connection_adapters/sqlite_adapter.rb b/activerecord/lib/active_record/connection_adapters/sqlite_adapter.rb
index 5390f49f04..afd6472db8 100644
--- a/activerecord/lib/active_record/connection_adapters/sqlite_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/sqlite_adapter.rb
@@ -17,9 +17,9 @@ module ActiveRecord
 
           # "Downgrade" deprecated sqlite API
           if SQLite.const_defined?(:Version)
-            ConnectionAdapters::SQLite2Adapter.new(db, logger)
+            ConnectionAdapters::SQLite2Adapter.new(db, logger, config)
           else
-            ConnectionAdapters::DeprecatedSQLiteAdapter.new(db, logger)
+            ConnectionAdapters::DeprecatedSQLiteAdapter.new(db, logger, config)
           end
         end
       end
@@ -72,10 +72,31 @@ module ActiveRecord
     #
     # * <tt>:database</tt> - Path to the database file.
     class SQLiteAdapter < AbstractAdapter
+      class Version
+        include Comparable
+
+        def initialize(version_string)
+          @version = version_string.split('.').map(&:to_i)
+        end
+
+        def <=>(version_string)
+          @version <=> version_string.split('.').map(&:to_i)
+        end
+      end
+
+      def initialize(connection, logger, config)
+        super(connection, logger)
+        @config = config
+      end
+
       def adapter_name #:nodoc:
         'SQLite'
       end
 
+      def supports_ddl_transactions?
+        sqlite_version >= '2.0.0'
+      end
+
       def supports_migrations? #:nodoc:
         true
       end
@@ -83,6 +104,10 @@ module ActiveRecord
       def requires_reloading?
         true
       end
+
+      def supports_add_column?
+        sqlite_version >= '3.1.6'
+      end
  
       def disconnect!
         super
@@ -164,7 +189,6 @@ module ActiveRecord
         catch_schema_changes { @connection.rollback }
       end
 
-
       # SELECT ... FOR UPDATE is redundant since the table is locked.
       def add_lock!(sql, options) #:nodoc:
         sql
@@ -213,14 +237,20 @@ module ActiveRecord
         execute "ALTER TABLE #{name} RENAME TO #{new_name}"
       end
 
+      # See: http://www.sqlite.org/lang_altertable.html
+      # SQLite has an additional restriction on the ALTER TABLE statement
+      def valid_alter_table_options( type, options)
+        type.to_sym != :primary_key
+      end
+
       def add_column(table_name, column_name, type, options = {}) #:nodoc:
-        if @connection.respond_to?(:transaction_active?) && @connection.transaction_active?
-          raise StatementInvalid, 'Cannot add columns to a SQLite database while inside a transaction'
+        if supports_add_column? && valid_alter_table_options( type, options )
+          super(table_name, column_name, type, options)
+        else
+          alter_table(table_name) do |definition|
+            definition.column(column_name, type, options)
+          end
         end
-        
-        super(table_name, column_name, type, options)
-        # See last paragraph on http://www.sqlite.org/lang_altertable.html
-        execute "VACUUM"
       end
 
       def remove_column(table_name, *column_names) #:nodoc:
@@ -380,7 +410,7 @@ module ActiveRecord
         end
 
         def sqlite_version
-          @sqlite_version ||= select_value('select sqlite_version(*)')
+          @sqlite_version ||= SQLiteAdapter::Version.new(select_value('select sqlite_version(*)'))
         end
 
         def default_primary_key_type
@@ -393,23 +423,9 @@ module ActiveRecord
     end
 
     class SQLite2Adapter < SQLiteAdapter # :nodoc:
-      def supports_count_distinct? #:nodoc:
-        false
-      end
-
       def rename_table(name, new_name)
         move_table(name, new_name)
       end
-
-      def add_column(table_name, column_name, type, options = {}) #:nodoc:
-        if @connection.respond_to?(:transaction_active?) && @connection.transaction_active?
-          raise StatementInvalid, 'Cannot add columns to a SQLite database while inside a transaction'
-        end
-
-        alter_table(table_name) do |definition|
-          definition.column(column_name, type, options)
-        end
-      end
     end
 
     class DeprecatedSQLiteAdapter < SQLite2Adapter # :nodoc: