1 files changed, 50 insertions, 0 deletions
diff --git a/activerecord/lib/active_record/connection_adapters/postgresql/schema_dumper.rb b/activerecord/lib/active_record/connection_adapters/postgresql/schema_dumper.rb
new file mode 100644
index 0000000000..84643d20da
--- /dev/null
+++ b/activerecord/lib/active_record/connection_adapters/postgresql/schema_dumper.rb
@@ -0,0 +1,50 @@
+# frozen_string_literal: true
+
+module ActiveRecord
+  module ConnectionAdapters
+    module PostgreSQL
+      class SchemaDumper < ConnectionAdapters::SchemaDumper # :nodoc:
+        private
+
+          def extensions(stream)
+            extensions = @connection.extensions
+            if extensions.any?
+              stream.puts "  # These are extensions that must be enabled in order to support this database"
+              extensions.sort.each do |extension|
+                stream.puts "  enable_extension #{extension.inspect}"
+              end
+              stream.puts
+            end
+          end
+
+          def prepare_column_options(column)
+            spec = super
+            spec[:array] = "true" if column.array?
+            spec
+          end
+
+          def default_primary_key?(column)
+            schema_type(column) == :bigserial
+          end
+
+          def explicit_primary_key_default?(column)
+            column.type == :uuid || (column.type == :integer && !column.serial?)
+          end
+
+          def schema_type(column)
+            return super unless column.serial?
+
+            if column.bigint?
+              :bigserial
+            else
+              :serial
+            end
+          end
+
+          def schema_expression(column)
+            super unless column.serial?
+          end
+      end
+    end
+  end
+end