Fix `reconnect!` to work after `disconnect!`

3 files changed, 25 insertions, 11 deletions

diff --git a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
index 05d8d5ac00..3990c0a71a 100644
--- a/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb
@@ -281,6 +281,8 @@ module ActiveRecord
           super
           @connection.reset
           configure_connection
+        rescue PG::ConnectionBad
+          connect
         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 cb3d34a740..5e9b3afae4 100644
--- a/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
+++ b/activerecord/lib/active_record/connection_adapters/sqlite3_adapter.rb
@@ -95,8 +95,6 @@ module ActiveRecord
 
       def initialize(connection, logger, connection_options, config)
         super(connection, logger, config)
-
-        @active = true
         configure_connection
       end
 
@@ -144,14 +142,18 @@ module ActiveRecord
       alias supports_insert_conflict_target? supports_insert_on_conflict?
 
       def active?
-        @active
+        !@connection.closed?
+      end
+
+      def reconnect!
+        super
+        connect if @connection.closed?
       end
 
       # Disconnects from the database if already connected. Otherwise, this
       # method does nothing.
       def disconnect!
         super
-        @active = false
         @connection.close rescue nil
       end
 
@@ -611,6 +613,14 @@ module ActiveRecord
           StatementPool.new(self.class.type_cast_config_to_integer(@config[:statement_limit]))
         end
 
+        def connect
+          @connection = ::SQLite3::Database.new(
+            @config[:database].to_s,
+            @config.merge(results_as_hash: true)
+          )
+          configure_connection
+        end
+
         def configure_connection
           execute("PRAGMA foreign_keys = ON", "SCHEMA")
         end
diff --git a/activerecord/test/cases/adapter_test.rb b/activerecord/test/cases/adapter_test.rb
index 2baf3db49a..03bd9fd384 100644
--- a/activerecord/test/cases/adapter_test.rb
+++ b/activerecord/test/cases/adapter_test.rb
@@ -452,16 +452,16 @@ module ActiveRecord
   class AdapterTestWithoutTransaction < ActiveRecord::TestCase
     self.use_transactional_tests = false
 
-    class Klass < ActiveRecord::Base
-    end
-
     def setup
-      Klass.establish_connection :arunit
-      @connection = Klass.connection
+      @connection = ActiveRecord::Base.connection
     end
 
-    teardown do
-      Klass.remove_connection
+    test "reconnect after a disconnect" do
+      assert_predicate @connection, :active?
+      @connection.disconnect!
+      assert_not_predicate @connection, :active?
+      @connection.reconnect!
+      assert_predicate @connection, :active?
     end
 
     unless in_memory_db?
@@ -477,6 +477,8 @@ module ActiveRecord
         assert_predicate @connection, :transaction_open?
         @connection.disconnect!
         assert_not_predicate @connection, :transaction_open?
+      ensure
+        @connection.reconnect!
       end
     end