1 files changed, 13 insertions, 3 deletions
diff --git a/activerecord/test/cases/adapters/postgresql/postgresql_adapter_test.rb b/activerecord/test/cases/adapters/postgresql/postgresql_adapter_test.rb
index 59ddb8457e..fbd3cbf90f 100644
--- a/activerecord/test/cases/adapters/postgresql/postgresql_adapter_test.rb
+++ b/activerecord/test/cases/adapters/postgresql/postgresql_adapter_test.rb
@@ -378,7 +378,7 @@ module ActiveRecord
 
       def test_errors_when_an_insert_query_is_called_while_preventing_writes
         with_example_table do
-          assert_raises(ActiveRecord::StatementInvalid) do
+          assert_raises(ActiveRecord::ReadOnlyError) do
             @connection.while_preventing_writes do
               @connection.execute("INSERT INTO ex (data) VALUES ('138853948594')")
             end
@@ -390,7 +390,7 @@ module ActiveRecord
         with_example_table do
           @connection.execute("INSERT INTO ex (data) VALUES ('138853948594')")
 
-          assert_raises(ActiveRecord::StatementInvalid) do
+          assert_raises(ActiveRecord::ReadOnlyError) do
             @connection.while_preventing_writes do
               @connection.execute("UPDATE ex SET data = '9989' WHERE data = '138853948594'")
             end
@@ -402,7 +402,7 @@ module ActiveRecord
         with_example_table do
           @connection.execute("INSERT INTO ex (data) VALUES ('138853948594')")
 
-          assert_raises(ActiveRecord::StatementInvalid) do
+          assert_raises(ActiveRecord::ReadOnlyError) do
             @connection.while_preventing_writes do
               @connection.execute("DELETE FROM ex where data = '138853948594'")
             end
@@ -432,6 +432,16 @@ module ActiveRecord
         end
       end
 
+      def test_doesnt_error_when_a_read_query_with_leading_chars_is_called_while_preventing_writes
+        with_example_table do
+          @connection.execute("INSERT INTO ex (data) VALUES ('138853948594')")
+
+          @connection.while_preventing_writes do
+            assert_equal 1, @connection.execute("(\n( SELECT * FROM ex WHERE data = '138853948594' ) )").entries.count
+          end
+        end
+      end
+
       private
 
         def with_example_table(definition = "id serial primary key, number integer, data character varying(255)", &block)