1 files changed, 47 insertions, 7 deletions
diff --git a/activerecord/lib/active_record/connection_adapters/abstract/schema_creation.rb b/activerecord/lib/active_record/connection_adapters/abstract/schema_creation.rb
index 47fe501752..18ff869ea6 100644
--- a/activerecord/lib/active_record/connection_adapters/abstract/schema_creation.rb
+++ b/activerecord/lib/active_record/connection_adapters/abstract/schema_creation.rb
@@ -1,3 +1,5 @@
+require 'active_support/core_ext/string/strip'
+
 module ActiveRecord
   module ConnectionAdapters
     class AbstractAdapter
@@ -13,9 +15,7 @@ module ActiveRecord
         end
 
         def visit_AddColumn(o)
-          sql_type = type_to_sql(o.type, o.limit, o.precision, o.scale)
-          sql = "ADD #{quote_column_name(o.name)} #{sql_type}"
-          add_column_options!(sql, column_options(o))
+          "ADD #{accept(o)}"
         end
 
         private
@@ -23,12 +23,14 @@ module ActiveRecord
           def visit_AlterTable(o)
             sql = "ALTER TABLE #{quote_table_name(o.name)} "
             sql << o.adds.map { |col| visit_AddColumn col }.join(' ')
+            sql << o.foreign_key_adds.map { |fk| visit_AddForeignKey fk }.join(' ')
+            sql << o.foreign_key_drops.map { |fk| visit_DropForeignKey fk }.join(' ')
           end
 
           def visit_ColumnDefinition(o)
             sql_type = type_to_sql(o.type, o.limit, o.precision, o.scale)
             column_sql = "#{quote_column_name(o.name)} #{sql_type}"
-            add_column_options!(column_sql, column_options(o)) unless o.primary_key?
+            add_column_options!(column_sql, column_options(o)) unless o.type == :primary_key
             column_sql
           end
 
@@ -41,6 +43,21 @@ module ActiveRecord
             create_sql
           end
 
+          def visit_AddForeignKey(o)
+            sql = <<-SQL.strip_heredoc
+              ADD CONSTRAINT #{quote_column_name(o.name)}
+              FOREIGN KEY (#{quote_column_name(o.column)})
+                REFERENCES #{quote_table_name(o.to_table)} (#{quote_column_name(o.primary_key)})
+            SQL
+            sql << " #{action_sql('DELETE', o.on_delete)}" if o.on_delete
+            sql << " #{action_sql('UPDATE', o.on_update)}" if o.on_update
+            sql
+          end
+
+          def visit_DropForeignKey(name)
+            "DROP CONSTRAINT #{quote_column_name(name)}"
+          end
+
           def column_options(o)
             column_options = {}
             column_options[:null] = o.null unless o.null.nil?
@@ -48,6 +65,8 @@ module ActiveRecord
             column_options[:column] = o
             column_options[:first] = o.first
             column_options[:after] = o.after
+            column_options[:auto_increment] = o.auto_increment
+            column_options[:primary_key] = o.primary_key
             column_options
           end
 
@@ -64,7 +83,7 @@ module ActiveRecord
           end
 
           def add_column_options!(sql, options)
-            sql << " DEFAULT #{quote_value(options[:default], options[:column])}" if options_include_default?(options)
+            sql << " DEFAULT #{quote_default_expression(options[:default], options[:column])}" if options_include_default?(options)
             # must explicitly check for :null to allow change_column to work on migrations
             if options[:null] == false
               sql << " NOT NULL"
@@ -72,18 +91,39 @@ module ActiveRecord
             if options[:auto_increment] == true
               sql << " AUTO_INCREMENT"
             end
+            if options[:primary_key] == true
+              sql << " PRIMARY KEY"
+            end
             sql
           end
 
-          def quote_value(value, column)
+          def quote_default_expression(value, column)
             column.sql_type ||= type_to_sql(column.type, column.limit, column.precision, column.scale)
+            value = type_for_column(column).type_cast_for_database(value)
 
-            @conn.quote(value, column)
+            @conn.quote(value)
           end
 
           def options_include_default?(options)
             options.include?(:default) && !(options[:null] == false && options[:default].nil?)
           end
+
+          def action_sql(action, dependency)
+            case dependency
+            when :nullify then "ON #{action} SET NULL"
+            when :cascade  then "ON #{action} CASCADE"
+            when :restrict then "ON #{action} RESTRICT"
+            else
+              raise ArgumentError, <<-MSG.strip_heredoc
+                '#{dependency}' is not supported for :on_update or :on_delete.
+                Supported values are: :nullify, :cascade, :restrict
+              MSG
+            end
+          end
+
+          def type_for_column(column)
+            @conn.lookup_cast_type(column.sql_type)
+          end
       end
     end
   end