dev-npgsql/npgsql: Npgsql is the .NET data provider for PostgreSQL.

test/Npgsql.Tests/ConnectionTests.cs
1 383 строки55 KB
Shay Rojansky
Stop requiring users to specify Integrated Security (#5687)
30 апр 2024, 01:34
30 апр 2024, 01:34337acb3
using System;
using System.Data;
using System.Diagnostics;
using System.IO;
using System.Linq;
using System.Net;
using System.Net.Security;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using Npgsql.Util;
using NUnit.Framework;
using NUnit.Framework.Internal;
using static Npgsql.Tests.TestUtil;

namespace Npgsql.Tests
{
    public class ConnectionTests : TestBase
    {
        [Test, Description("Makes sure the connection goes through the proper state lifecycle")]
        //[Timeout(5000)]
        public void BasicLifecycle()
        {
            using (var conn = new NpgsqlConnection(ConnectionString))
            {
                bool eventOpen = false, eventClosed = false, eventBroken = false;
                conn.StateChange += (s, e) =>
                {
                    if (e.OriginalState == ConnectionState.Closed && e.CurrentState == ConnectionState.Open)
                        eventOpen = true;
                    if (e.OriginalState == ConnectionState.Open && e.CurrentState == ConnectionState.Closed)
                        eventClosed = true;
                };

                Assert.That(conn.State, Is.EqualTo(ConnectionState.Closed));
                Assert.That(conn.FullState, Is.EqualTo(ConnectionState.Closed));

                // TODO: Connecting state?

                conn.Open();
                Assert.That(conn.State, Is.EqualTo(ConnectionState.Open));
                Assert.That(conn.FullState, Is.EqualTo(ConnectionState.Open));
                Assert.That(conn.Connector!.State, Is.EqualTo(ConnectorState.Ready));
                Assert.That(eventOpen, Is.True);

                using (var cmd = new NpgsqlCommand("SELECT 1", conn))
                using (var reader = cmd.ExecuteReader())
                {
                    reader.Read();
                    Assert.That(conn.FullState, Is.EqualTo(ConnectionState.Open | ConnectionState.Fetching));
                    Assert.That(conn.State, Is.EqualTo(ConnectionState.Open));
                    Assert.That(conn.Connector.State, Is.EqualTo(ConnectorState.Fetching));
                }

                Assert.That(conn.FullState, Is.EqualTo(ConnectionState.Open));
                Assert.That(conn.State, Is.EqualTo(ConnectionState.Open));
                Assert.That(conn.Connector.State, Is.EqualTo(ConnectorState.Ready));

                using (var cmd = CreateSleepCommand(conn, 1))
                {
                    var exitFlag = false;
                    var pollingTask = Task.Factory.StartNew(() =>
                    {
                        while (true)
                        {
                            if (exitFlag) {
                                Assert.Fail("Connection did not reach the Executing state");
                            }
                            if (conn.Connector.State == ConnectorState.Executing)
                            {
                                Assert.That(conn.FullState & ConnectionState.Executing, Is.Not.EqualTo(0));
                                Assert.That(conn.State, Is.EqualTo(ConnectionState.Open));
                                return;
                            }
                        }
                    });
                    cmd.ExecuteNonQuery();
                    exitFlag = true;
                    pollingTask.Wait();
                }

                conn.Close();
                Assert.That(conn.State, Is.EqualTo(ConnectionState.Closed));
                Assert.That(conn.FullState, Is.EqualTo(ConnectionState.Closed));
                Assert.That(eventClosed, Is.True);

                conn.Open();
                Assert.That(conn.State, Is.EqualTo(ConnectionState.Open));
                Assert.That(conn.FullState, Is.EqualTo(ConnectionState.Open));
                Assert.That(conn.Connector.State, Is.EqualTo(ConnectorState.Ready));

                using (var conn2 = OpenConnection())
                    conn2.ExecuteNonQuery($"SELECT pg_terminate_backend({conn.ProcessID})");

                conn.StateChange += (sender, args) =>
                {
                    if (args.CurrentState == ConnectionState.Closed)
                        eventBroken = true;
                };

                // Allow some time for the pg_terminate to kill our connection
                using (var cmd = CreateSleepCommand(conn, 10))
                    Assert.That(() => cmd.ExecuteNonQuery(), Throws.Exception
                        .AssignableTo<NpgsqlException>()
                    );

                Assert.That(conn.State, Is.EqualTo(ConnectionState.Closed));
                Assert.That(conn.FullState, Is.EqualTo(ConnectionState.Broken));
                Assert.That(eventBroken, Is.True);
            }
        }

        #region Connection Errors

#if IGNORE
        [Test]
        [TestCase(true)]
        [TestCase(false)]
        public void ConnectionRefused(bool pooled)
        {
            var csb = new NpgsqlConnectionStringBuilder(ConnectionString) { Port = 44444, Pooling = pooled };
            using (var conn = new NpgsqlConnection(csb)) {
                Assert.That(() => conn.Open(), Throws.Exception
                    .TypeOf<SocketException>()
                    // CoreCLR currently has an issue which causes the wrong SocketErrorCode to be set on Linux:
                    // https://github.com/dotnet/corefx/issues/8464
                    .With.Property(nameof(SocketException.SocketErrorCode)).EqualTo(SocketError.ConnectionRefused)
                );
                Assert.That(conn.FullState, Is.EqualTo(ConnectionState.Closed));
            }
        }

        [Test]
        [TestCase(true)]
        [TestCase(false)]
        public void ConnectionRefusedAsync(bool pooled)
        {
            var csb = new NpgsqlConnectionStringBuilder(ConnectionString) { Port = 44444, Pooling = pooled };
            using (var conn = new NpgsqlConnection(csb))
            {
                Assert.That(async () => await conn.OpenAsync(), Throws.Exception
                    .TypeOf<SocketException>()
                    .With.Property(nameof(SocketException.SocketErrorCode)).EqualTo(SocketError.ConnectionRefused)
                );
                Assert.That(conn.FullState, Is.EqualTo(ConnectionState.Closed));
            }
        }
#endif

        [Test]
        [Ignore("Fails in a non-determinstic manner and only on the build server... investigate...")]
        public void InvalidUserId()
        {
            var connString = new NpgsqlConnectionStringBuilder(ConnectionString)
            {
                Username = "unknown", Pooling = false
            }.ToString();
            using (var conn = new NpgsqlConnection(connString))
            {
                Assert.That(conn.Open, Throws.Exception
                    .TypeOf<PostgresException>()
                    .With.Property(nameof(PostgresException.SqlState)).EqualTo("28P01")
                );
                Assert.That(conn.FullState, Is.EqualTo(ConnectionState.Closed));
            }
        }

        [Test, Description("Connects with a bad password to ensure the proper error is thrown")]
        public void AuthenticationFailure()
        {
            if (Environment.GetEnvironmentVariable("TRAVIS") != null)
                Assert.Ignore("Test mysteriously fails on Travis only");
            var connString = new NpgsqlConnectionStringBuilder(ConnectionString)
            {
                Username = "doesnt_exist",
                Password = "bad",
                Pooling = false
            }.ToString();
            using (var conn = new NpgsqlConnection(connString))
            {
                Assert.That(() => conn.Open(), Throws.Exception
                    .TypeOf<PostgresException>()
                    .With.Property(nameof(PostgresException.SqlState)).StartsWith("28")
                );
                Assert.That(conn.FullState, Is.EqualTo(ConnectionState.Closed));
            }
        }

        #region ProvidePasswordCallback Tests

        [Test, Description("ProvidePasswordCallback is used when password is not supplied in connection string")]
        public void ProvidePasswordCallbackDelegateIsUsed()
        {
            if (TestUtil.IsOnBuildServer && PGUtil.IsWindows)
            {
                Assert.Ignore("Somehow on Github Actions on Windows we log in successfully with this");
                return;
            }


            var connString = new NpgsqlConnectionStringBuilder(ConnectionString)
            {
                Pooling = false
            };

            var getPasswordDelegateWasCalled = false;
            var goodPassword = connString.Password;
            connString.Password = null;

            using (SetEnvironmentVariable("PGPASSFILE", "Must Not Exist"))
            using (var conn = new NpgsqlConnection(connString.ToString()) { ProvidePasswordCallback = ProvidePasswordCallback })
            {
                conn.Open();
                Assert.True(getPasswordDelegateWasCalled, "ProvidePasswordCallback delegate not used");
            }

            string ProvidePasswordCallback(string host, int port, string database, string username)
            {
                getPasswordDelegateWasCalled = true;
                return goodPassword!;
            }
        }

        [Test, Description("ProvidePasswordCallback is not used when password is supplied in connection string")]
        public void ProvidePasswordCallbackDelegateIsNotUsed()
        {
            var connString = new NpgsqlConnectionStringBuilder(ConnectionString)
            {
                Pooling = false
            };

            using (var conn = new NpgsqlConnection(connString.ToString()) { ProvidePasswordCallback = ProvidePasswordCallback })
            {
                Assert.DoesNotThrow(() => conn.Open());
            }

            string ProvidePasswordCallback(string host, int port, string database, string username)
            {
                throw new Exception("password should come from connection string, not delegate");
            }
        }

        [Test, Description("Exceptions thrown from client application are wrapped when using ProvidePasswordCallback Delegate")]
        public void ProvidePasswordCallbackDelegateExceptionsAreWrapped()
        {
            if (TestUtil.IsOnBuildServer && PGUtil.IsWindows)
            {
                Assert.Ignore("Somehow on Github Actions on Windows we log in successfully with this");
                return;
            }

            var connString = new NpgsqlConnectionStringBuilder(ConnectionString)
            {
                Pooling = false,
                Password = null
            };

            using (SetEnvironmentVariable("PGPASSFILE", "Must Not Exist"))
            using (var conn = new NpgsqlConnection(connString.ToString()) { ProvidePasswordCallback = ProvidePasswordCallback })
            {
                Assert.That(() => conn.Open(), Throws.Exception
                    .TypeOf<NpgsqlException>()
                    .With.InnerException.Message.EqualTo("inner exception from ProvidePasswordCallback")
                );
            }

            string ProvidePasswordCallback(string host, int port, string database, string username)
            {
                throw new Exception("inner exception from ProvidePasswordCallback");
            }
        }

        [Test, Description("Parameters passed to ProvidePasswordCallback delegate are correct")]
        public void ProvidePasswordCallbackDelegateGetsCorrectArguments()
        {
            if (TestUtil.IsOnBuildServer && PGUtil.IsWindows)
            {
                Assert.Ignore("Somehow on Github Actions on Windows we log in successfully with this");
                return;
            }

            var connString = new NpgsqlConnectionStringBuilder(ConnectionString) { Pooling = false };
            var goodPassword = connString.Password;
            connString.Password = null;

            string? receivedHost = null;
            int? receivedPort = null;
            string? receivedDatabase = null;
            string? receivedUsername = null;

            using (SetEnvironmentVariable("PGPASSFILE", "Must Not Exist"))
            using (var conn = new NpgsqlConnection(connString.ToString()) { ProvidePasswordCallback = ProvidePasswordCallback })
            {
                conn.Open();
                Assert.AreEqual(connString.Host, receivedHost);
                Assert.AreEqual(connString.Port, receivedPort);
                Assert.AreEqual(connString.Database, receivedDatabase);
                Assert.AreEqual(connString.Username, receivedUsername);
            }

            string ProvidePasswordCallback(string host, int port, string database, string username)
            {
                receivedHost = host;
                receivedPort = port;
                receivedDatabase = database;
                receivedUsername = username;

                return goodPassword!;
            }
        }
        #endregion

        [Test]
        public void BadDatabase()
        {
            var connString = new NpgsqlConnectionStringBuilder(ConnectionString)
            {
                Database = "does_not_exist"
            }.ToString();
            using (var conn = new NpgsqlConnection(connString))
                Assert.That(() => conn.Open(),
                    Throws.Exception.TypeOf<PostgresException>()
                    .With.Property(nameof(PostgresException.SqlState)).EqualTo("3D000")
                );
        }

        [Test, Description("Tests that mandatory connection string parameters are indeed mandatory")]
        public void MandatoryConnectionStringParams()
        {
            Assert.That(() => new NpgsqlConnection("User ID=npgsql_tests;Password=npgsql_tests;Database=npgsql_tests").Open(), Throws.Exception.TypeOf<ArgumentException>());
        }


        [Test, Description("Reuses the same connection instance for a failed connection, then a successful one")]
        public void FailConnectThenSucceed()
        {
            var dbName = TestUtil.GetUniqueIdentifier(nameof(FailConnectThenSucceed));
            using (var conn1 = OpenConnection())
            {
                conn1.ExecuteNonQuery($"DROP DATABASE IF EXISTS \"{dbName}\"");
                try
                {
                    var connString = new NpgsqlConnectionStringBuilder(ConnectionString)
                    {
                        Database = dbName,
                        Pooling = false
                    }.ToString();

                    using (var conn2 = new NpgsqlConnection(connString))
                    {
                        Assert.That(() => conn2.Open(),
                            Throws.Exception.TypeOf<PostgresException>()
                            .With.Property(nameof(PostgresException.SqlState)).EqualTo("3D000") // database doesn't exist
                        );
                        Assert.That(conn2.FullState, Is.EqualTo(ConnectionState.Closed));

                        conn1.ExecuteNonQuery($"CREATE DATABASE \"{dbName}\" TEMPLATE template0");

                        conn2.Open();
                        conn2.Close();
                    }
                }
                finally
                {
                    //conn1.ExecuteNonQuery($"DROP DATABASE IF EXISTS \"{dbName}\"");
                }
            }
        }

        [Test]
        [Timeout(10000)]
        public void ConnectTimeout()
        {
            var unknownIp = Environment.GetEnvironmentVariable("NPGSQL_UNKNOWN_IP");
            if (unknownIp == null)
                Assert.Ignore("NPGSQL_UNKNOWN_IP isn't defined and is required for connection timeout tests");

            var csb = new NpgsqlConnectionStringBuilder(ConnectionString) {
                Host = unknownIp,
                Pooling = false,
                Timeout = 2
            };
            using (var conn = new NpgsqlConnection(csb.ToString()))
            {
                var sw = Stopwatch.StartNew();
                Assert.That(() => conn.Open(), Throws.Exception.TypeOf<TimeoutException>());
                Assert.That(sw.Elapsed.TotalMilliseconds, Is.GreaterThanOrEqualTo((csb.Timeout * 1000) - 100),
                    $"Timeout was supposed to happen after {csb.Timeout} seconds, but fired after {sw.Elapsed.TotalSeconds}");
                Assert.That(conn.State, Is.EqualTo(ConnectionState.Closed));
            }
        }

        [Test]
        [Timeout(10000)]
        public void ConnectTimeoutAsync()
        {
            var unknownIp = Environment.GetEnvironmentVariable("NPGSQL_UNKNOWN_IP");
            if (unknownIp == null)
                Assert.Ignore("NPGSQL_UNKNOWN_IP isn't defined and is required for connection timeout tests");

            var connString = new NpgsqlConnectionStringBuilder(ConnectionString)
            {
                Host = unknownIp,
                Pooling = false,
                Timeout = 2
            }.ToString();
            using (var conn = new NpgsqlConnection(connString))
            {
                Assert.That(async () => await conn.OpenAsync(), Throws.Exception.TypeOf<TimeoutException>());
                Assert.That(conn.State, Is.EqualTo(ConnectionState.Closed));
            }
        }

        [Test]
        [Timeout(10000)]
        public void ConnectTimeoutCancel()
        {
            var unknownIp = Environment.GetEnvironmentVariable("NPGSQL_UNKNOWN_IP");
            if (unknownIp == null)
                Assert.Ignore("NPGSQL_UNKNOWN_IP isn't defined and is required for connection cancellation tests");

            var connString = new NpgsqlConnectionStringBuilder(ConnectionString)
            {
                Host = unknownIp,
                Pooling = false,
                Timeout = 30
            }.ToString();
            using (var conn = new NpgsqlConnection(connString))
            {
                var cts = new CancellationTokenSource(1000);
                Assert.That(async () => await conn.OpenAsync(cts.Token), Throws.Exception.TypeOf<OperationCanceledException>());
                Assert.That(conn.State, Is.EqualTo(ConnectionState.Closed));
            }
        }

        #endregion

        #region Keepalive

        [Test, Description("Makes sure that if keepalive is enabled, broken connections are detected")]
        [Timeout(10000)]
        public void Keepalive()
        {
            var csbWithKeepAlive = new NpgsqlConnectionStringBuilder(ConnectionString) { KeepAlive = 1 };
            var mre = new ManualResetEvent(false);
            using (var conn1 = OpenConnection())
            using (var conn2 = OpenConnection(csbWithKeepAlive))
            {
                conn2.StateChange += (sender, args) =>
                {
                    if (args.CurrentState == ConnectionState.Closed)
                        mre.Set();
                };

                // Use another connection to kill our keepalive connection
                conn1.ExecuteNonQuery($"SELECT pg_terminate_backend({conn2.ProcessID})");
                mre.WaitOne();
                Assert.That(conn2.State, Is.EqualTo(ConnectionState.Closed));
                Assert.That(conn2.FullState, Is.EqualTo(ConnectionState.Broken));
            }
        }

        #endregion

        #region Client Encoding

        [Test, IssueLink("https://github.com/npgsql/npgsql/issues/1065")]
        public void ClientEncodingIsUTF8ByDefault()
        {
            using (var conn = OpenConnection())
                Assert.That(conn.ExecuteScalar("SHOW client_encoding"), Is.EqualTo("UTF8"));
        }

        [Test, IssueLink("https://github.com/npgsql/npgsql/issues/1065")]
        [NonParallelizable]
        public void ClientEncodingEnvVar()
        {
            using (var conn = OpenConnection())
                Assert.That(conn.ExecuteScalar("SHOW client_encoding"), Is.Not.EqualTo("SQL_ASCII"));
            using (TestUtil.SetEnvironmentVariable("PGCLIENTENCODING", "SQL_ASCII"))
            {
                // Note that the pool is unaware of the environment variable, so if a connection is
                // returned from the pool it may contain the wrong client_encoding
                var connString = new NpgsqlConnectionStringBuilder(ConnectionString)
                {
                    Pooling = false
                };
                using (var conn = OpenConnection(connString))
                    Assert.That(conn.ExecuteScalar("SHOW client_encoding"), Is.EqualTo("SQL_ASCII"));
            }
        }

        [Test, IssueLink("https://github.com/npgsql/npgsql/issues/1065")]
        public void ClientEncodingConnectionParam()
        {
            using (var conn = OpenConnection())
                Assert.That(conn.ExecuteScalar("SHOW client_encoding"), Is.Not.EqualTo("SQL_ASCII"));
            var connString = new NpgsqlConnectionStringBuilder(ConnectionString) {
                ClientEncoding = "SQL_ASCII",
                Pooling = false
            };
            using (var conn = OpenConnection(connString))
                Assert.That(conn.ExecuteScalar("SHOW client_encoding"), Is.EqualTo("SQL_ASCII"));
        }

        #endregion Client Encoding

        #region Timezone

        [Test, IssueLink("https://github.com/npgsql/npgsql/issues/1634")]
        [NonParallelizable]
        public void TimezoneEnvVar()
        {
            string newTimezone;
            using (var conn = OpenConnection())
            {
                newTimezone = (string)conn.ExecuteScalar("SHOW TIMEZONE") == "Africa/Bamako"
                    ? "Africa/Lagos"
                    : "Africa/Bamako";
            }

            using (TestUtil.SetEnvironmentVariable("PGTZ", newTimezone))
            {
                // Note that the pool is unaware of the environment variable, so if a connection is
                // returned from the pool it may contain the wrong timezone
                var connString = new NpgsqlConnectionStringBuilder(ConnectionString)
                {
                    Pooling = false
                };
                using (var conn = OpenConnection(connString))
                    Assert.That(conn.ExecuteScalar("SHOW TIMEZONE"), Is.EqualTo(newTimezone));
            }
        }

        [Test, IssueLink("https://github.com/npgsql/npgsql/issues/1634")]
        public void TimezoneConnectionParam()
        {
            string newTimezone;
            using (var conn = OpenConnection())
            {
                newTimezone = (string)conn.ExecuteScalar("SHOW TIMEZONE") == "Africa/Bamako"
                    ? "Africa/Lagos"
                    : "Africa/Bamako";
            }

            var connString = new NpgsqlConnectionStringBuilder(ConnectionString)
            {
                Timezone = newTimezone,
                Pooling = false
            };
            using (var conn = OpenConnection(connString))
                Assert.That(conn.ExecuteScalar("SHOW TIMEZONE"), Is.EqualTo(newTimezone));
        }

        #endregion Timezone

        [Test, Explicit("Doesn't work on Windows, sometimes not available Linux (e.g. when PG is in docker)")]
        public void UnixDomainSocket()
        {
            var port = new NpgsqlConnectionStringBuilder(ConnectionString).Port;
            var candidateDirectories = new[] { "/var/run/postgresql", "/tmp" };
            var dir = candidateDirectories.FirstOrDefault(d => File.Exists(Path.Combine(d, $".s.PGSQL.{port}")));
            if (dir == null)
            {
                TestUtil.IgnoreExceptOnBuildServer("No PostgreSQL unix domain socket was found");
                return;
            }

            var csb = new NpgsqlConnectionStringBuilder(ConnectionString)
            {
                Host=dir,
                Username=null  // Let Npgsql detect the username
            };
            using (var conn = OpenConnection(csb))
            {
                Assert.That(conn.ExecuteScalar("SELECT 1"), Is.EqualTo(1));
            }
        }

        [Test, IssueLink("https://github.com/npgsql/npgsql/issues/903")]
        public void DataSource()
        {
            using (var conn = new NpgsqlConnection(ConnectionString))
                Assert.That(conn.DataSource, Is.EqualTo($"tcp://{conn.Host}:{conn.Port}"));

            var bld = new NpgsqlConnectionStringBuilder(ConnectionString);
            bld.Host = "Otherhost";

            using (var conn = new NpgsqlConnection(bld.ToString()))
                Assert.That(conn.DataSource, Is.EqualTo($"tcp://{conn.Host}:{conn.Port}"));

            bld = new NpgsqlConnectionStringBuilder(ConnectionString);
            bld.Port = 5435;

            using (var conn = new NpgsqlConnection(bld.ToString()))
                Assert.That(conn.DataSource, Is.EqualTo($"tcp://{conn.Host}:{conn.Port}"));
        }

        [Test]
        public void SetConnectionString()
        {
            using (var conn = new NpgsqlConnection())
            {
                conn.ConnectionString = ConnectionString;
                conn.Open();
                Assert.That(() => conn.ConnectionString = "", Throws.Exception.TypeOf<InvalidOperationException>());
            }
        }

        [Test]
        public void EmptyCtor()
        {
            var conn = new NpgsqlConnection();
            Assert.That(conn.ConnectionTimeout, Is.EqualTo(NpgsqlConnectionStringBuilder.DefaultTimeout));
            Assert.That(conn.ConnectionString, Is.SameAs(string.Empty));
            Assert.That(() => conn.Open(), Throws.Exception.TypeOf<InvalidOperationException>());
        }

        [Test, IssueLink("https://github.com/npgsql/npgsql/issues/703")]
        public void NoDatabaseDefaultsToUsername()
        {
            var csb = new NpgsqlConnectionStringBuilder(ConnectionString) { Database = null };
            using (var conn = new NpgsqlConnection(csb.ToString()))
            {
                Assert.That(conn.Database, Is.EqualTo(csb.Username));
                conn.Open();
                Assert.That(conn.ExecuteScalar("SELECT current_database()"), Is.EqualTo(csb.Username));
                Assert.That(conn.Database, Is.EqualTo(csb.Username));
            }
        }

        [Test, Description("Breaks a connector while it's in the pool, with a keepalive and without")]
        [TestCase(false, TestName = "BreakConnectorInPoolWithoutKeepAlive")]
        [TestCase(true, TestName = "BreakConnectorInPoolWithKeepAlive")]
        public void BreakConnectorInPool(bool keepAlive)
        {
            var csb = new NpgsqlConnectionStringBuilder(ConnectionString) { MaxPoolSize = 1 };
            if (keepAlive)
                csb.KeepAlive = 1;
            using (var conn = new NpgsqlConnection(csb.ToString()))
            {
                conn.Open();
                var connectorId = conn.ProcessID;
                conn.Close();

                // Use another connection to kill the connector currently in the pool
                using (var conn2 = OpenConnection())
                    conn2.ExecuteNonQuery($"SELECT pg_terminate_backend({connectorId})");

                // Allow some time for the terminate to occur
                Thread.Sleep(2000);

                conn.Open();
                Assert.That(conn.FullState, Is.EqualTo(ConnectionState.Open));
                if (keepAlive)
                {
                    Assert.That(conn.ProcessID, Is.Not.EqualTo(connectorId));
                    Assert.That(conn.ExecuteScalar("SELECT 1"), Is.EqualTo(1));
                }
                else
                {
                    Assert.That(conn.ProcessID, Is.EqualTo(connectorId));
                    Assert.That(() => conn.ExecuteScalar("SELECT 1"), Throws.Exception
                        .AssignableTo<NpgsqlException>());
                }
            }
        }

        #region ChangeDatabase

        [Test]
        public void ChangeDatabase()
        {
            using (var conn = OpenConnection())
            {
                conn.ChangeDatabase("template1");
                using (var cmd = new NpgsqlCommand("select current_database()", conn))
                    Assert.That(cmd.ExecuteScalar(), Is.EqualTo("template1"));
            }
        }

        [Test]
        public void ChangeDatabaseDoesNotAffectOtherConnections()
        {
            using (var conn1 = new NpgsqlConnection(ConnectionString))
            using (var conn2 = new NpgsqlConnection(ConnectionString))
            {
                // Connection 1 changes database
                conn1.Open();
                conn1.ChangeDatabase("template1");
                Assert.That(conn1.ExecuteScalar("SELECT current_database()"), Is.EqualTo("template1"));

                // Connection 2's database should not changed
                conn2.Open();
                Assert.That(conn2.ExecuteScalar("SELECT current_database()"), Is.Not.EqualTo(conn1.Database));
            }
        }

        [Test, IssueLink("https://github.com/npgsql/npgsql/issues/1331")]
        public void ChangeDatabaseConnectionNotOpen()
        {
            using (var conn = new NpgsqlConnection(ConnectionString))
                Assert.That(() => conn.ChangeDatabase("template1"), Throws.Exception
                    .TypeOf<InvalidOperationException>()
                    .With.Message.EqualTo("Connection is not open"));
        }

        #endregion

        [Test, Description("Tests closing a connector while a reader is open")]
        [TestCase(true)]
        [TestCase(false)]
        [Timeout(10000)]
        public void CloseDuringRead(bool pooled)
        {
            var csb = new NpgsqlConnectionStringBuilder(ConnectionString);
            if (pooled)
                csb.MaxPoolSize = 1;
            else
                csb.Pooling = false;

            using (var conn = OpenConnection(csb))
            {
                var connectorId = conn.ProcessID;
                using (var cmd = new NpgsqlCommand("SELECT 1", conn))
                using (var reader = cmd.ExecuteReader())
                {
                    reader.Read();
                    conn.Close();
                    Assert.That(conn.State, Is.EqualTo(ConnectionState.Closed));
                    Assert.That(reader.IsClosed);
                }

                conn.Open();
                if (pooled)   // Make sure we can reuse the pooled connector
                    Assert.That(conn.ProcessID, Is.EqualTo(connectorId));
                Assert.That(conn.FullState, Is.EqualTo(ConnectionState.Open));
                Assert.That(conn.ExecuteScalar("SELECT 1"), Is.EqualTo(1));
            }
        }

        [Test]
        public void SearchPath()
        {
            using (var conn = OpenConnection(new NpgsqlConnectionStringBuilder(ConnectionString) { SearchPath = "foo" }))
                Assert.That(conn.ExecuteScalar("SHOW search_path"), Contains.Substring("foo"));
        }

        [Test]
        public void ConnectorNotInitializedException1000581()
        {
            var command = new NpgsqlCommand();
            command.CommandText = @"SELECT 123";

            for (var i = 0; i < 2; i++)
            {
                using (var connection = new NpgsqlConnection(ConnectionString))
                {
                    connection.Open();
                    command.Connection = connection;
                    var tx = connection.BeginTransaction();
                    command.ExecuteScalar();
                    tx.Commit();
                }
            }
        }

        [Test]
        [Ignore("")]
        public void NpgsqlErrorRepro1()
        {
            throw new NotImplementedException();
#if WHAT_TO_DO_WITH_THIS
            using (var connection = new NpgsqlConnection(ConnectionString))
            {
                connection.Open();
                using (var transaction = connection.BeginTransaction())
                {
                    var largeObjectMgr = new LargeObjectManager(connection);
                    try
                    {
                        var largeObject = largeObjectMgr.Open(-1, LargeObjectManager.READWRITE);
                        transaction.Commit();
                    }
                    catch
                    {
                        // ignore the LO failure
                    }
                } // *1* sometimes it throws "System.NotSupportedException: This stream does not support seek operations"

                using (var command = connection.CreateCommand())
                {
                    command.CommandText = "SELECT * FROM pg_database";
                    using (var reader = command.ExecuteReader())
                    {
                        Assert.IsTrue(reader.Read()); // *2* this fails if the initial connection is used
                    }
                }
            } // *3* sometimes it throws "System.NotSupportedException: This stream does not support seek operations"
#endif
        }

        [Test]
        public void Bug1011001()
        {
            //[#1011001] Bug in NpgsqlConnectionStringBuilder affects on cache and connection pool

            var csb1 = new NpgsqlConnectionStringBuilder(@"Server=server;Port=5432;User Id=user;Password=passwor;Database=database;");
            var cs1 = csb1.ToString();
            var csb2 = new NpgsqlConnectionStringBuilder(cs1);
            var cs2 = csb2.ToString();
            Assert.IsTrue(cs1 == cs2);
        }

        [Test]
        public void NpgsqlErrorRepro2()
        {
#if WHAT_TO_DO_WITH_THIS
            var connection = new NpgsqlConnection(ConnectionString);
            connection.Open();
            var transaction = connection.BeginTransaction();
            var largeObjectMgr = new LargeObjectManager(connection);
            try
            {
                var largeObject = largeObjectMgr.Open(-1, LargeObjectManager.READWRITE);
                transaction.Commit();
            }
            catch
            {
                // ignore the LO failure
                try
                {
                    transaction.Dispose();
                }
                catch
                {
                    // ignore dispose failure
                }
                try
                {
                    connection.Dispose();
                }
                catch
                {
                    // ignore dispose failure
                }
            }

            using (connection = new NpgsqlConnection(ConnectionString))
            {
                connection.Open();
                using (var command = connection.CreateCommand())
                {
                    command.CommandText = "SELECT * FROM pg_database";
                    using (var reader = command.ExecuteReader())
                    {
                        Assert.IsTrue(reader.Read());
                        // *1* this fails if the connection for the pool happens to be the bad one from above
                        Assert.IsTrue(!String.IsNullOrEmpty((string)reader["datname"]));
                    }
                }
            }
#endif
        }

        [Test]
        public void GetConnectionState()
        {
            // Test created to PR #164

            var c = new NpgsqlConnection();
            c.Dispose();
            Assert.AreEqual(ConnectionState.Closed, c.State);
        }

        [Test]
        public void ChangeApplicationNameWithConnectionStringBuilder()
        {
            // Test for issue #165 on github.
            var builder = new NpgsqlConnectionStringBuilder();
            builder.ApplicationName = "test";
        }

        [Test, Description("Makes sure notices are probably received and emitted as events")]
        public void Notice()
        {
            if (Environment.GetEnvironmentVariable("TRAVIS") != null)
                Assert.Ignore("Test mysteriously fails on Travis only");
            using (var conn = OpenConnection())
            {
                // Make sure messages are in English
                conn.ExecuteNonQuery(@"SET lc_messages='en_US.UTF-8'");
                conn.ExecuteNonQuery(@"
                        CREATE OR REPLACE FUNCTION pg_temp.emit_notice() RETURNS VOID AS
                        'BEGIN RAISE NOTICE ''testnotice''; END;'
                        LANGUAGE 'plpgsql';
                ");

                var mre = new ManualResetEvent(false);
                PostgresNotice? notice = null;
                NoticeEventHandler action = (sender, args) =>
                {
                    notice = args.Notice;
                    mre.Set();
                };
                conn.Notice += action;
                try
                {
                    conn.ExecuteNonQuery("SELECT pg_temp.emit_notice()::TEXT"); // See docs for CreateSleepCommand
                    mre.WaitOne(5000);
                    Assert.That(notice, Is.Not.Null, "No notice was emitted");
                    Assert.That(notice!.MessageText, Is.EqualTo("testnotice"));
                    Assert.That(notice.Severity, Is.EqualTo("NOTICE"));
                }
                finally
                {
                    conn.Notice -= action;
                }
            }
        }

        [Test, Description("Makes sure that concurrent use of the connection throws an exception")]
        public void ConcurrentUse()
        {
            using (var conn = OpenConnection())
            {
                using (var cmd = new NpgsqlCommand("SELECT 1", conn))
                using (cmd.ExecuteReader())
                    Assert.That(() => conn.ExecuteScalar("SELECT 2"),
                        Throws.Exception.TypeOf<NpgsqlOperationInProgressException>()
                            .With.Property(nameof(NpgsqlOperationInProgressException.CommandInProgress)).SameAs(cmd));

                conn.ExecuteNonQuery("CREATE TEMP TABLE foo (bar INT)");
                using (conn.BeginBinaryImport("COPY foo (bar) FROM STDIN BINARY"))
                {
                    Assert.That(() => conn.ExecuteScalar("SELECT 2"),
                        Throws.Exception.TypeOf<NpgsqlOperationInProgressException>()
                            .With.Message.Contains("Copy"));
                }
            }
        }

        [Test]
        [IssueLink("https://github.com/npgsql/npgsql/issues/783")]
        public void PersistSecurityInfoIsOn([Values(true, false)] bool pooling)
        {
            var connString = new NpgsqlConnectionStringBuilder(ConnectionString)
            {
                PersistSecurityInfo = true,
                Pooling = pooling
            }.ToString();
            using (var conn = new NpgsqlConnection(connString))
            {
                var passwd = new NpgsqlConnectionStringBuilder(conn.ConnectionString).Password;
                Assert.That(passwd, Is.Not.Null);
                conn.Open();
                Assert.That(new NpgsqlConnectionStringBuilder(conn.ConnectionString).Password, Is.EqualTo(passwd));
            }
        }

        [Test]
        [IssueLink("https://github.com/npgsql/npgsql/issues/783")]
        public void NoPasswordWithoutPersistSecurityInfo([Values(true, false)] bool pooling)
        {
            var connString = new NpgsqlConnectionStringBuilder(ConnectionString)
            {
                Pooling = pooling
            }.ToString();
            using (var conn = new NpgsqlConnection(connString))
            {
                var csb = new NpgsqlConnectionStringBuilder(conn.ConnectionString);
                Assert.That(csb.PersistSecurityInfo, Is.False);
                Assert.That(csb.Password, Is.Not.Null);
                conn.Open();
                Assert.That(new NpgsqlConnectionStringBuilder(conn.ConnectionString).Password, Is.Null);
            }
        }

        [Test, IssueLink("https://github.com/npgsql/npgsql/issues/2725")]
        public void CloneWithAndPersistSecurityInfo()
        {
            var csb = new NpgsqlConnectionStringBuilder(ConnectionString)
            {
                PersistSecurityInfo = true,
                Pooling = false
            };

            var connStringWithPersist = csb.ToString();
            using var connWithPersist = new NpgsqlConnection(connStringWithPersist);

            // First un-persist, should work
            csb.PersistSecurityInfo = false;
            var connStringWithoutPersist = csb.ToString();
            using var clonedWithoutPersist = connWithPersist.CloneWith(connStringWithoutPersist);
            clonedWithoutPersist.Open();

            Assert.That(clonedWithoutPersist.ConnectionString, Does.Not.Contain("Password="));

            // Then attempt to re-persist, should not work
            using var clonedConn = clonedWithoutPersist.CloneWith(connStringWithPersist);
            clonedConn.Open();

            Assert.That(clonedConn.ConnectionString, Does.Not.Contain("Password="));
        }

        [Test]
        [IssueLink("https://github.com/npgsql/npgsql/issues/743")]
        [IssueLink("https://github.com/npgsql/npgsql/issues/783")]
        public void Clone()
        {
            var connString = new NpgsqlConnectionStringBuilder(ConnectionString)
            {
                Pooling = false
            }.ToString();
            using (var conn = new NpgsqlConnection(connString))
            {
                ProvideClientCertificatesCallback callback1 = certificates => { };
                conn.ProvideClientCertificatesCallback = callback1;
                RemoteCertificateValidationCallback callback2 = (sender, certificate, chain, errors) => true;
                conn.UserCertificateValidationCallback = callback2;

                conn.Open();
                using (var conn2 = (NpgsqlConnection)((ICloneable)conn).Clone())
                {
                    Assert.That(conn2.ConnectionString, Is.EqualTo(conn.ConnectionString));
                    Assert.That(conn2.ProvideClientCertificatesCallback, Is.SameAs(callback1));
                    Assert.That(conn2.UserCertificateValidationCallback, Is.SameAs(callback2));
                    conn2.Open();
                }
            }
        }

        [Test, IssueLink("https://github.com/npgsql/npgsql/issues/824")]
        public void ReloadTypes()
        {
            var connString = new NpgsqlConnectionStringBuilder(ConnectionString)
            {
                ApplicationName = nameof(ReloadTypes)
            }.ToString();
            using (var conn = OpenConnection(connString))
            using (var conn2 = OpenConnection(connString))
            {
                Assert.That(conn.ExecuteScalar("SELECT EXISTS (SELECT * FROM pg_type WHERE typname='reload_types_enum')"),
                    Is.False);
                conn.ExecuteNonQuery("CREATE TYPE pg_temp.reload_types_enum AS ENUM ('First', 'Second')");
                Assert.That(() => conn.TypeMapper.MapEnum<ReloadTypesEnum>(), Throws.Exception.TypeOf<ArgumentException>());
                conn.ReloadTypes();
                conn.TypeMapper.MapEnum<ReloadTypesEnum>();

                // Make sure conn2 picks up the new type after a pooled close
                var connId = conn2.ProcessID;
                conn2.Close();
                conn2.Open();
                Assert.That(conn2.ProcessID, Is.EqualTo(connId), "Didn't get the same connector back");
                conn2.TypeMapper.MapEnum<ReloadTypesEnum>();

                NpgsqlConnection.ClearPool(conn);
            }
        }
        enum ReloadTypesEnum { First, Second };

        [Test]
        public void DatabaseInfoIsShared()
        {
            using (var conn1 = OpenConnection())
            using (var conn2 = OpenConnection())
                Assert.That(conn1.Connector!.DatabaseInfo, Is.SameAs(conn2.Connector!.DatabaseInfo));
        }

        [Test, IssueLink("https://github.com/npgsql/npgsql/issues/736")]
        public void ManyOpenClose()
        {
            // The connector's _sentRfqPrependedMessages is a byte, too many open/closes made it overflow
            for (var i = 0; i < 255; i++)
            {
                using (var conn = new NpgsqlConnection(ConnectionString))
                {
                    conn.Open();
                }
            }
            using (var conn = new NpgsqlConnection(ConnectionString))
            {
                conn.Open();
            }
            using (var conn = new NpgsqlConnection(ConnectionString))
            {
                conn.Open();
                Assert.That(conn.ExecuteScalar("SELECT 1"), Is.EqualTo(1));
            }
        }

        [Test, IssueLink("https://github.com/npgsql/npgsql/issues/736")]
        public void ManyOpenCloseWithTransaction()
        {
            // The connector's _sentRfqPrependedMessages is a byte, too many open/closes made it overflow
            for (var i = 0; i < 255; i++)
            {
                using (var conn = OpenConnection())
                    conn.BeginTransaction();
            }
            using (var conn = OpenConnection())
                Assert.That(conn.ExecuteScalar("SELECT 1"), Is.EqualTo(1));
        }

        [Test]
        [IssueLink("https://github.com/npgsql/npgsql/issues/927")]
        [IssueLink("https://github.com/npgsql/npgsql/issues/736")]
        [Ignore("Fails when running the entire test suite but not on its own...")]
        public void RollbackOnClose()
        {
            // Npgsql 3.0.0 to 3.0.4 prepended a rollback for the next time the connector is used, as an optimization.
            // This caused some issues (#927) and was removed.

            // Clear connections in pool as we're going to need to reopen the same connection
            var dummyConn = new NpgsqlConnection(ConnectionString);
            NpgsqlConnection.ClearPool(dummyConn);

            int processId;
            using (var conn = OpenConnection())
            {
                processId = conn.Connector!.BackendProcessId;
                conn.BeginTransaction();
                conn.ExecuteNonQuery("SELECT 1");
                Assert.That(conn.Connector.TransactionStatus, Is.EqualTo(TransactionStatus.InTransactionBlock));
            }
            using (var conn = OpenConnection())
            {
                Assert.That(conn.Connector!.BackendProcessId, Is.EqualTo(processId));
                Assert.That(conn.Connector.TransactionStatus, Is.EqualTo(TransactionStatus.Idle));
            }
        }

        [Test, Description("Tests an exception happening when sending the Terminate message while closing a ready connector")]
        [IssueLink("https://github.com/npgsql/npgsql/issues/777")]
        [Ignore("Flaky")]
        public void ExceptionDuringClose()
        {
            var csb = new NpgsqlConnectionStringBuilder(ConnectionString) { Pooling = false };
            using (var conn = OpenConnection(csb))
            {
                var connectorId = conn.ProcessID;

                using (var conn2 = OpenConnection())
                    conn2.ExecuteNonQuery($"SELECT pg_terminate_backend({connectorId})");

                conn.Close();
            }
        }

        [Test, IssueLink("https://github.com/npgsql/npgsql/issues/1180")]
        [Ignore("Flaky")]
        public void PoolByPassword()
        {
            NpgsqlConnection? goodConn = null;
            try
            {
                var csb = new NpgsqlConnectionStringBuilder(ConnectionString)
                {
                    ApplicationName = nameof(PoolByPassword)
                };
                using (goodConn = new NpgsqlConnection(csb.ToString()))
                    goodConn.Open();
                csb.Password = "badpasswd";
                using (var conn = new NpgsqlConnection(csb.ToString()))
                    Assert.That(conn.Open, Throws.Exception.TypeOf<PostgresException>());
            }
            finally
            {
                if (goodConn != null)
                    NpgsqlConnection.ClearPool(goodConn);
            }
        }

        [Test, Description("Some pseudo-PG database don't support pg_type loading, we have a minimal DatabaseInfo for this")]
        public void NoTypeLoading()
        {
            var connString = new NpgsqlConnectionStringBuilder(ConnectionString)
            {
                ApplicationName = nameof(NoTypeLoading),
                ServerCompatibilityMode = ServerCompatibilityMode.NoTypeLoading
            }.ToString();

            try
            {
                using (var conn = OpenConnection(connString))
                {
                    // Arrays should not be supported in this mode
                    Assert.That(() => conn.ExecuteScalar("SELECT '{1,2,3}'::INTEGER[]"),
                        Throws.Exception.TypeOf<NotSupportedException>());
                    // Test that some basic types do work
                    Assert.That(conn.ExecuteScalar("SELECT 8"), Is.EqualTo(8));
                    Assert.That(conn.ExecuteScalar("SELECT 'foo'"), Is.EqualTo("foo"));
                    Assert.That(conn.ExecuteScalar("SELECT TRUE"), Is.EqualTo(true));
                    Assert.That(conn.ExecuteScalar("SELECT INET '192.168.1.1'"),
                        Is.EqualTo(IPAddress.Parse("192.168.1.1")));
                }
            }
            finally
            {
                NpgsqlConnection.ClearPool(new NpgsqlConnection(connString));
            }
        }

        [Test, IssueLink("https://github.com/npgsql/npgsql/issues/1158")]
        public void TableNamedRecord()
        {
            using (var conn = OpenConnection())
            {
                conn.ExecuteNonQuery("CREATE TABLE record ()");
                try
                {
                    conn.ReloadTypes();
                    Assert.That(conn.ExecuteScalar("SELECT COUNT(*) FROM record"), Is.Zero);
                }
                finally
                {
                    conn.ExecuteNonQuery("DROP TABLE record");
                }
            }
        }

#if NET461
        [Test, IssueLink("https://github.com/npgsql/npgsql/issues/392")]
        public void NonUTF8Encoding()
        {
            using (var adminConn = OpenConnection())
            {
                // Create the database with server encoding sql-ascii
                adminConn.ExecuteNonQuery("DROP DATABASE IF EXISTS sqlascii");
                adminConn.ExecuteNonQuery("CREATE DATABASE sqlascii ENCODING 'sql_ascii' TEMPLATE template0");
                try
                {
                    // Insert some win1252 data
                    var goodCsb = new NpgsqlConnectionStringBuilder(ConnectionString)
                    {
                        Database = "sqlascii",
                        Encoding = "windows-1252",
                        ClientEncoding = "sql-ascii",
                        Pooling = false
                    };
                    using (var conn = OpenConnection(goodCsb))
                    {
                        conn.ExecuteNonQuery("CREATE TABLE foo (bar TEXT)");
                        conn.ExecuteNonQuery("INSERT INTO foo (bar) VALUES ('éàç')");
                        Assert.That(conn.ExecuteScalar("SELECT * FROM foo"), Is.EqualTo("éàç"));
                    }

                    // A normal connection with the default UTF8 encoding and client_encoding should fail
                    var badCsb = new NpgsqlConnectionStringBuilder(ConnectionString)
                    {
                        Database = "sqlascii",
                        Pooling = false
                    };
                    using (var conn = OpenConnection(badCsb))
                    {
                        Assert.That(() => conn.ExecuteScalar("SELECT * FROM foo"),
                            Throws.Exception.TypeOf<PostgresException>()
                                .With.Property(nameof(PostgresException.SqlState)).EqualTo("22021")
                                .Or.TypeOf<DecoderFallbackException>()
                        );
                    }
                }
                finally
                {
                    adminConn.ExecuteNonQuery("DROP DATABASE IF EXISTS sqlascii");
                }
            }
        }
#endif

        [Test]
        public void OversizeBuffer()
        {
            var csb = new NpgsqlConnectionStringBuilder(ConnectionString)
            {
                ApplicationName = nameof(OversizeBuffer)
            };
            using (var conn = OpenConnection(csb))
            {
                Assert.That(conn.Connector!.ReadBuffer.Size, Is.EqualTo(csb.ReadBufferSize));

                // Read a big row, we should now be using an oversize buffer
                var bigString1 = new string('x', csb.ReadBufferSize + 10);
                using (var cmd = new NpgsqlCommand($"SELECT '{bigString1}'", conn))
                using (var reader = cmd.ExecuteReader())
                {
                    reader.Read();
                    Assert.That(reader.GetString(0), Is.EqualTo(bigString1));
                }
                var size1 = conn.Connector.ReadBuffer.Size;
                Assert.That(conn.Connector.ReadBuffer.Size, Is.GreaterThan(csb.ReadBufferSize));

                // Even bigger oversize buffer
                var bigString2 = new string('x', csb.ReadBufferSize + 20);
                using (var cmd = new NpgsqlCommand($"SELECT '{bigString2}'", conn))
                using (var reader = cmd.ExecuteReader())
                {
                    reader.Read();
                    Assert.That(reader.GetString(0), Is.EqualTo(bigString2));
                }
                Assert.That(conn.Connector.ReadBuffer.Size, Is.GreaterThan(size1));

                var processId = conn.ProcessID;
                conn.Close();
                conn.Open();
                Assert.That(conn.ProcessID, Is.EqualTo(processId));
                Assert.That(conn.Connector.ReadBuffer.Size, Is.EqualTo(csb.ReadBufferSize));

            }
        }

        [Test, Explicit, Description("Turns on TCP keepalive and sleeps forever, good for wiresharking")]
        public void TcpKeepaliveTime()
        {
            var csb = new NpgsqlConnectionStringBuilder(ConnectionString)
            {
                TcpKeepAliveTime = 2000
            };
            using (OpenConnection(csb))
                Thread.Sleep(Timeout.Infinite);
        }

        [Test, Explicit, Description("Turns on TCP keepalive and sleeps forever, good for wiresharking")]
        public void TcpKeepalive()
        {
            var csb = new NpgsqlConnectionStringBuilder(ConnectionString)
            {
                TcpKeepAlive = true
            };
            using (OpenConnection(csb))
                Thread.Sleep(Timeout.Infinite);
        }

        [Test]
        public void ChangeParameter()
        {
            using (var conn = OpenConnection())
            {
                var defaultApplicationName = conn.PostgresParameters["application_name"];
                conn.ExecuteNonQuery("SET application_name = 'some_test_value'");
                Assert.That(conn.PostgresParameters["application_name"], Is.EqualTo("some_test_value"));
                conn.ExecuteNonQuery("SET application_name = 'some_test_value2'");
                Assert.That(conn.PostgresParameters["application_name"], Is.EqualTo("some_test_value2"));
                conn.ExecuteNonQuery($"SET application_name = '{defaultApplicationName}'");
                Assert.That(conn.PostgresParameters["application_name"], Is.EqualTo(defaultApplicationName));
            }
        }

        #region pgpass

        [Test]
        public void UsePgPassFile()
        {
            var file = SetupTestData();
            using var resetter = TestUtil.SetEnvironmentVariable("PGPASSFILE", file);

            var builder = new NpgsqlConnectionStringBuilder(ConnectionString)
            {
                Pooling = false,
                Password = null
            };
            using (OpenConnection(builder)) { }
        }

        public string SetupTestData()
        {
            // set up pgpass file with connection credentials
            var builder = new NpgsqlConnectionStringBuilder(ConnectionString);
            var content = $"*:*:*:{builder.Username}:{builder.Password}";
            var pgpassFile = Path.GetTempFileName();
            File.WriteAllText(pgpassFile, content);
            return pgpassFile;
        }

        public void RestorePriorConfiguration(string fileName, string environmentVariableValue)
        {
            if (File.Exists(fileName))
                File.Delete(fileName);
        }

        #endregion
    }
}