Stop the slow test packages waiting (closes #263)

- Tests hash passwords at bcrypt.MinCost, set through the
  PasswordCost field of db.Params.
- Test IRC servers check the queue only on broker notification;
  one test keeps the 100 ms fallback poll.
- The stop-timeout test shortens the timeout through a test-only
  setter.
- service and handlers tests build config.Config directly instead
  of through config.New, so they run in parallel: service had run
  serially, and handlers started its servers one at a time.
- Repeated race trials run as parallel subtests.
- Fixed sleeps become waits on the broker.
- A new test covers the relay's failed queue read, which only the
  100 ms poll had reached.

Model: opus-5-5

internal/db/auth.go

@@ -22,7 +22,7 @@ func (database *Database) SetPassword(
 	password string,
 ) error {
 	hash, err := bcrypt.GenerateFromPassword(
-		[]byte(password), bcrypt.DefaultCost,
+		[]byte(password), database.passwordCost,
 	)
 	if err != nil {
 		return fmt.Errorf("hash password: %w", err)

internal/db/db.go

@@ -15,6 +15,7 @@ import (
 	"strings"
 
 	"go.uber.org/fx"
+	"golang.org/x/crypto/bcrypt"
 	"sneak.berlin/go/neoirc/internal/config"
 	"sneak.berlin/go/neoirc/internal/logger"
 
@@ -39,13 +40,19 @@ type Params struct {
 
 	Logger *logger.Logger
 	Config *config.Config
+
+	// PasswordCost is the bcrypt cost at which SetPassword hashes
+	// a password. The server leaves it unset, which means
+	// bcrypt.DefaultCost. Tests set a lower cost to save time.
+	PasswordCost int `optional:"true"`
 }
 
 // Database manages the SQLite connection and migrations.
 type Database struct {
-	conn   *sql.DB
+	conn         *sql.DB
-	log    *slog.Logger
+	log          *slog.Logger
-	params *Params
+	params       *Params
+	passwordCost int
 }
 
 // New creates a new Database and registers lifecycle hooks.
@@ -53,9 +60,15 @@ func New(
 	lifecycle fx.Lifecycle,
 	params Params,
 ) (*Database, error) {
+	passwordCost := params.PasswordCost
+	if passwordCost == 0 {
+		passwordCost = bcrypt.DefaultCost
+	}
+
 	database := &Database{ //nolint:exhaustruct // conn set in OnStart
-		params: &params,
+		params:       &params,
-		log:    params.Logger.Get(),
+		log:          params.Logger.Get(),
+		passwordCost: passwordCost,
 	}
 
 	database.log.Info("Database instantiated")

internal/db/export_test.go

@@ -8,10 +8,12 @@ import (
 	"testing"
 	"time"
 
+	"golang.org/x/crypto/bcrypt"
 	"sneak.berlin/go/neoirc/internal/dbtest"
 )
 
-// NewTestDatabase creates an in-memory database for testing.
+// NewTestDatabase creates an in-memory database for testing. It
+// hashes passwords at bcrypt.MinCost.
 func NewTestDatabase(tb testing.TB) (*Database, error) {
 	tb.Helper()
 
@@ -23,8 +25,9 @@ func NewTestDatabase(tb testing.TB) (*Database, error) {
 	}
 
 	database := &Database{ //nolint:exhaustruct // test helper, params not needed
-		conn: conn,
+		conn:         conn,
-		log:  slog.Default(),
+		log:          slog.Default(),
+		passwordCost: bcrypt.MinCost,
 	}
 
 	err = database.runMigrations(context.Background())

internal/handlers/api_test.go

@@ -145,13 +145,6 @@ type testServer struct {
 	handlers   *handlers.Handlers
 }
 
-// viperMu makes tests start their servers one at a time,
-// because config.New writes the global viper instance and
-// the server reads it as it starts.
-//
-//nolint:gochecknoglobals // guards a global, so must be one
-var viperMu sync.Mutex
-
 func newTestServer(
 	t *testing.T,
 ) *testServer {
@@ -167,9 +160,6 @@ func newTestServerWith(
 ) *testServer {
 	t.Helper()
 
-	viperMu.Lock()
-	defer viperMu.Unlock()
-
 	dbURL := dbtest.NewURL(t)
 	copyTemplateDB(t, dbURL)
 
@@ -184,31 +174,20 @@ func newTestServerWith(
 		fx.Provide(
 			newTestGlobals,
 			logger.New,
-			func(
+			// Built here rather than by config.New, which writes
-				lifecycle fx.Lifecycle,
+			// the global viper instance, so servers start in
-				globs *globals.Globals,
+			// parallel. Settings left out take their defaults.
-				log *logger.Logger,
+			func() *config.Config {
-			) (*config.Config, error) {
+				return &config.Config{
-				cfg, err := config.New(
+					DBURL: dbURL,
-					lifecycle, config.Params{ //nolint:exhaustruct
+					// One line: each line is a database write per new session.
-						Globals: globs, Logger: log,
+					MOTD:          "neoirc test server",
-					},
+					HashcashBits:  hashcashBits,
-				)
+					OperName:      operName,
-				if err != nil {
+					OperPassword:  operPassword,
-					return nil, fmt.Errorf(
+					MessageMaxAge: "720h",
-						"test config: %w", err,
+					QueueMaxAge:   "720h",
-					)
 				}
-
-				cfg.DBURL = dbURL
-				cfg.Port = 0
-				// One line: each line is a database write per new session.
-				cfg.MOTD = "neoirc test server"
-				cfg.HashcashBits = hashcashBits
-				cfg.OperName = operName
-				cfg.OperPassword = operPassword
-
-				return cfg, nil
 			},
 			newTestDB,
 			broker.New,
@@ -255,7 +234,7 @@ func newTestDB(
 	cfg *config.Config,
 ) (*db.Database, error) {
 	database, err := db.New(lifecycle, db.Params{ //nolint:exhaustruct
-		Logger: log, Config: cfg,
+		Logger: log, Config: cfg, PasswordCost: bcrypt.MinCost,
 	})
 	if err != nil {
 		return nil, fmt.Errorf("test db: %w", err)
@@ -1750,52 +1729,67 @@ func TestConcurrentQuitsSendOneQuit(t *testing.T) {
 // that the second session then holds one QUIT from the
 // first, and that the first session is deleted: its tokens
 // are refused and its nick is free. It does all this
-// quitRaceTrials times, each on a new server, because each
+// quitRaceTrials times, at once, each on a new server, because
-// trial logs in and logins are rate limited.
+// each trial logs in and logins are rate limited.
 func checkQuitRace(
 	t *testing.T,
 	leave func(tserver *testServer, tokens []string),
 ) {
 	t.Helper()
 
+	for trial := range quitRaceTrials {
+		t.Run(fmt.Sprintf("trial %d", trial), func(t *testing.T) {
+			t.Parallel()
+
+			checkQuitRaceOnce(t, newTestServer(t), leave)
+		})
+	}
+}
+
+// checkQuitRaceOnce runs one trial of checkQuitRace on
+// tserver.
+func checkQuitRaceOnce(
+	t *testing.T,
+	tserver *testServer,
+	leave func(tserver *testServer, tokens []string),
+) {
+	t.Helper()
+
 	const nick = "racingquitter"
 
-	for trial := range quitRaceTrials {
+	firstToken := tserver.createSession(nick)
-		tserver := newTestServer(t)
+	observerToken := tserver.createSession("raceobserver")
-		firstToken := tserver.createSession(nick)
-		observerToken := tserver.createSession("raceobserver")
 
-		tserver.setPassword(nick)
+	tserver.setPassword(nick)
 
-		tokens := []string{firstToken, tserver.login(nick)}
+	tokens := []string{firstToken, tserver.login(nick)}
 
-		for _, token := range []string{firstToken, observerToken} {
+	for _, token := range []string{firstToken, observerToken} {
-			tserver.sendCommand(token, map[string]any{
+		tserver.sendCommand(token, map[string]any{
-				commandKey: joinCmd, toKey: "#quitrace",
+			commandKey: joinCmd, toKey: "#quitrace",
-			})
+		})
-		}
-
-		_, lastID := tserver.pollMessages(observerToken, 0)
-
-		leave(tserver, tokens)
-
-		msgs, _ := tserver.pollMessages(observerToken, lastID)
-
-		quits := countQuits(msgs, nick)
-		if quits != 1 {
-			t.Errorf("trial %d: %d QUITs, want 1: %v", trial, quits, msgs)
-		}
-
-		for _, token := range tokens {
-			status, _ := tserver.getState(token)
-			if status != http.StatusUnauthorized {
-				t.Errorf("trial %d: state got %d, want 401", trial, status)
-			}
-		}
-
-		// createSession fails the test if the nick is taken.
-		tserver.createSession(nick)
 	}
+
+	_, lastID := tserver.pollMessages(observerToken, 0)
+
+	leave(tserver, tokens)
+
+	msgs, _ := tserver.pollMessages(observerToken, lastID)
+
+	quits := countQuits(msgs, nick)
+	if quits != 1 {
+		t.Errorf("%d QUITs, want 1: %v", quits, msgs)
+	}
+
+	for _, token := range tokens {
+		status, _ := tserver.getState(token)
+		if status != http.StatusUnauthorized {
+			t.Errorf("state got %d, want 401", status)
+		}
+	}
+
+	// createSession fails the test if the nick is taken.
+	tserver.createSession(nick)
 }
 
 // TestLogoutOfOneClientKeepsSession checks that when one of
@@ -1933,11 +1927,28 @@ const (
 	// return once the session has left.
 	quitWakeDeadline = 5 * time.Second
 
-	// pollWaitStep is how often checkQuitWakesPoll checks
+	// pollWaitStep is how often waitForLongPoll checks
 	// whether the long poll is waiting yet.
 	pollWaitStep = 10 * time.Millisecond
 )
 
+// waitForLongPoll waits until a long poll of the session
+// sessionID is waiting, and fails the test if none is within
+// quitWakeDeadline.
+func (tserver *testServer) waitForLongPoll(sessionID int64) {
+	tserver.t.Helper()
+
+	deadline := time.Now().Add(quitWakeDeadline)
+
+	for tserver.broker.ListenerCount(sessionID) == 0 {
+		if time.Now().After(deadline) {
+			tserver.t.Fatal("the long poll did not start waiting")
+		}
+
+		time.Sleep(pollWaitStep)
+	}
+}
+
 // TestQuitWakesPeerLongPoll checks that a session's QUIT
 // wakes the long poll of a user who shares a channel with
 // it.
@@ -2012,15 +2023,7 @@ func checkQuitWakesPoll(
 		msgs, pollErr = tserver.longPoll(peerToken, lastID, quitWakePollTimeout)
 	}()
 
-	deadline := time.Now().Add(quitWakeDeadline)
+	tserver.waitForLongPoll(peerID)
-
-	for tserver.broker.ListenerCount(peerID) == 0 {
-		if time.Now().After(deadline) {
-			t.Fatal("the long poll did not start waiting")
-		}
-
-		time.Sleep(pollWaitStep)
-	}
 
 	leave(tserver, token)
 
@@ -2850,7 +2853,12 @@ func TestLongPoll(t *testing.T) {
 		pollMsgs = result.Messages
 	}()
 
-	time.Sleep(200 * time.Millisecond)
+	bobID, err := tserver.database.GetSessionByNick(t.Context(), "lp_bob")
+	if err != nil {
+		t.Fatalf("get session of lp_bob: %v", err)
+	}
+
+	tserver.waitForLongPoll(bobID)
 
 	tserver.sendCommand(aliceToken, map[string]any{
 		commandKey: privmsgCmd,

internal/ircserver/conn.go

@@ -70,6 +70,10 @@ type Conn struct {
 	closed      bool
 	killed      bool
 
+	// pollInterval is how often the relay checks the client
+	// output queue when no broker notification arrives.
+	pollInterval time.Duration
+
 	// quitReason is the reason in the QUIT that peers are
 	// sent when the connection ends. The client's QUIT
 	// replaces it.
@@ -83,6 +87,7 @@ func newConn(
 	brk *broker.Broker,
 	cfg *config.Config,
 	svc *service.Service,
+	poll time.Duration,
 ) *Conn {
 	host, _, _ := net.SplitHostPort(tcpConn.RemoteAddr().String())
 
@@ -101,6 +106,8 @@ func newConn(
 		serverSfx:  srvName,
 		remoteIP:   host,
 		quitReason: "Connection closed",
+
+		pollInterval: poll,
 	}
 
 	conn.commands = conn.buildCommandMap()

internal/ircserver/export_test.go

@@ -14,16 +14,16 @@ import (
 )
 
 // NewTestServer creates a Server suitable for testing, whose
-// connections use interval and deadline in place of
+// connections use interval, deadline and poll in place of
-// pingInterval and pongDeadline, and resolve in place of
+// pingInterval, pongDeadline and pollInterval, and resolve in
-// resolveHost.
+// place of resolveHost.
 // The caller must call Stop() when finished.
 func NewTestServer(
 	log *slog.Logger,
 	cfg *config.Config,
 	database *db.Database,
 	brk *broker.Broker,
-	interval, deadline time.Duration,
+	interval, deadline, poll time.Duration,
 	resolve func(ctx context.Context, addr string) string,
 ) *Server {
 	globs := &globals.Globals{
@@ -46,10 +46,18 @@ func NewTestServer(
 
 		pingInterval: interval,
 		pongDeadline: deadline,
+		pollInterval: poll,
+		stopTimeout:  stopTimeout,
 		resolveHost:  resolve,
 	}
 }
 
+// SetStopTimeout makes Stop wait at most timeout for the
+// connections' cleanup.
+func (s *Server) SetStopTimeout(timeout time.Duration) {
+	s.stopTimeout = timeout
+}
+
 // ResolveHost is the reverse DNS lookup that a server made by
 // New does for each client.
 func ResolveHost(ctx context.Context, addr string) string {
@@ -99,10 +107,6 @@ const PingInterval = pingInterval
 // for a line before it closes the connection.
 const PongDeadline = pongDeadline
 
-// StopTimeout is the longest Stop waits for the connections'
-// cleanup.
-const StopTimeout = stopTimeout
-
 // NewTestConn returns a Conn for nick on tcpConn, without a
 // server, database or service behind it.
 func NewTestConn(
@@ -111,7 +115,7 @@ func NewTestConn(
 	tcpConn net.Conn,
 	nick string,
 ) *Conn {
-	conn := newConn(tcpConn, log, nil, nil, cfg, nil)
+	conn := newConn(tcpConn, log, nil, nil, cfg, nil, pollInterval)
 	conn.nick = nick
 
 	return conn

internal/ircserver/integration_test.go

@@ -3,7 +3,6 @@ package ircserver_test
 import (
 	"strings"
 	"testing"
-	"time"
 
 	"sneak.berlin/go/neoirc/internal/config"
 )
@@ -1508,9 +1507,6 @@ func TestIntegrationThirdClientObserver(t *testing.T) {
 	bob.joinAndDrain("#trio")
 	carol.joinAndDrain("#trio")
 
-	// Drain join notifications.
-	time.Sleep(100 * time.Millisecond)
-
 	// alice sends; both bob and carol should receive.
 	alice.send("PRIVMSG #trio :hello trio")
 

internal/ircserver/relay.go

@@ -17,7 +17,7 @@ import (
 func (c *Conn) relayMessages(ctx context.Context) {
 	// Use a ticker as a fallback; primary wakeup is via
 	// broker notification.
-	ticker := time.NewTicker(pollInterval)
+	ticker := time.NewTicker(c.pollInterval)
 	defer ticker.Stop()
 
 	for {

internal/ircserver/relay_test.go

@@ -9,6 +9,7 @@ import (
 	"time"
 
 	"golang.org/x/crypto/bcrypt"
+	"sneak.berlin/go/neoirc/internal/config"
 	"sneak.berlin/go/neoirc/internal/dbtest"
 	"sneak.berlin/go/neoirc/internal/ircserver"
 	"sneak.berlin/go/neoirc/internal/service"
@@ -58,7 +59,11 @@ func (env *testEnv) queueMessage(
 func TestRelayKeepsOneWaitChannel(t *testing.T) {
 	t.Parallel()
 
-	env := newTestEnv(t)
+	env := newTestEnvWithResolver(
+		t, &config.Config{ServerName: testServerName},
+		ircserver.PingInterval, ircserver.PongDeadline,
+		ircserver.PollInterval, ircserver.ResolveHost,
+	)
 
 	client := env.dial(t)
 	client.register("idle")
@@ -119,6 +124,63 @@ func (env *testEnv) checkOneWaitChannel(
 	}
 }
 
+// TestRelayDeliversAfterFailedRead checks that when the relay
+// cannot read the client output queue, it waits for the next
+// notification, and delivers once the queue can be read again.
+func TestRelayDeliversAfterFailedRead(t *testing.T) {
+	t.Parallel()
+
+	env := newTestEnv(t)
+	client := env.dial(t)
+	client.register("reader")
+
+	sessionID, err := env.database.GetSessionByNick(t.Context(), "reader")
+	if err != nil {
+		t.Fatalf("get session of reader: %v", err)
+	}
+
+	dbtest.Exec(t, env.dbURL,
+		"ALTER TABLE client_queues RENAME TO hidden_queues")
+
+	// Each pass of the relay takes a wait channel and then reads
+	// the queue. Once it holds a channel after the second
+	// notification, the read after the first one has failed.
+	for range 2 {
+		env.waitForWaitChannel(t, sessionID)
+		env.brk.Notify(sessionID)
+	}
+
+	env.waitForWaitChannel(t, sessionID)
+
+	dbtest.Exec(t, env.dbURL,
+		"ALTER TABLE hidden_queues RENAME TO client_queues")
+
+	env.queueMessage(
+		t, "reader", "PRIVMSG", "carol", "reader", []string{"readable"},
+	)
+
+	client.readUntil(func(l string) bool {
+		return strings.Contains(l, "readable")
+	})
+}
+
+// waitForWaitChannel waits until the session sessionID holds a
+// broker wait channel, and fails the test if it does not
+// within testTimeout.
+func (env *testEnv) waitForWaitChannel(t *testing.T, sessionID int64) {
+	t.Helper()
+
+	deadline := time.Now().Add(testTimeout)
+
+	for env.brk.ListenerCount(sessionID) == 0 {
+		if time.Now().After(deadline) {
+			t.Fatal("the relay is not waiting for a notification")
+		}
+
+		time.Sleep(relayCheckStep)
+	}
+}
+
 // TestRelayMultiLineBody checks that each line of a PRIVMSG
 // or NOTICE body sent over the HTTP API reaches an IRC
 // listener user as its own line.

internal/ircserver/server.go

@@ -53,6 +53,11 @@ type Server struct {
 	pingInterval time.Duration
 	pongDeadline time.Duration
 
+	// pollInterval and stopTimeout are the constants of the
+	// same names, except in tests, which change them.
+	pollInterval time.Duration
+	stopTimeout  time.Duration
+
 	// resolveHost is the function of the same name, except in
 	// tests, which replace it with one that blocks.
 	resolveHost func(ctx context.Context, addr string) string
@@ -79,6 +84,8 @@ func New(
 
 		pingInterval: pingInterval,
 		pongDeadline: pongDeadline,
+		pollInterval: pollInterval,
+		stopTimeout:  stopTimeout,
 		resolveHost:  resolveHost,
 	}
 
@@ -154,10 +161,10 @@ func (s *Server) stop() {
 
 	select {
 	case <-done:
-	case <-time.After(stopTimeout):
+	case <-time.After(s.stopTimeout):
 		s.log.Error(
 			"irc connections not cleaned up before stop timeout",
-			"timeout", stopTimeout,
+			"timeout", s.stopTimeout,
 		)
 	}
 }
@@ -181,7 +188,7 @@ func (s *Server) acceptLoop(ctx context.Context) {
 
 		client := newConn(
 			tcpConn, s.log,
-			s.database, s.brk, s.cfg, s.svc,
+			s.database, s.brk, s.cfg, s.svc, s.pollInterval,
 		)
 
 		s.mu.Lock()

internal/ircserver/server_test.go

@@ -18,6 +18,7 @@ import (
 	"time"
 
 	"go.uber.org/fx/fxtest"
+	"golang.org/x/crypto/bcrypt"
 	"sneak.berlin/go/neoirc/internal/broker"
 	"sneak.berlin/go/neoirc/internal/config"
 	"sneak.berlin/go/neoirc/internal/db"
@@ -32,6 +33,12 @@ import (
 
 const testTimeout = 5 * time.Second
 
+// testPollInterval is how often the relay of a test server
+// checks the client output queue without a broker
+// notification. It is so long that the relay delivers only on
+// notification, and a test fails when one is missing.
+const testPollInterval = time.Hour
+
 // testEnv holds the shared test infrastructure.
 type testEnv struct {
 	dbURL    string
@@ -91,16 +98,19 @@ func newTestEnvWithPingTimes(
 	t.Helper()
 
 	return newTestEnvWithResolver(
-		t, cfg, interval, deadline, ircserver.ResolveHost,
+		t, cfg, interval, deadline, testPollInterval,
+		ircserver.ResolveHost,
 	)
 }
 
 // newTestEnvWithResolver is newTestEnvWithPingTimes, except
-// that the server looks up a client's hostname with resolve.
+// that the relay checks the client output queue every poll
+// without a broker notification, and the server looks up a
+// client's hostname with resolve.
 func newTestEnvWithResolver(
 	t *testing.T,
 	cfg *config.Config,
-	interval, deadline time.Duration,
+	interval, deadline, poll time.Duration,
 	resolve func(ctx context.Context, addr string) string,
 ) *testEnv {
 	t.Helper()
@@ -116,8 +126,9 @@ func newTestEnvWithResolver(
 	}
 
 	database, err := db.New(lifecycle, db.Params{
-		Logger: dbLog,
+		Logger:       dbLog,
-		Config: &config.Config{DBURL: dbURL},
+		Config:       &config.Config{DBURL: dbURL},
+		PasswordCost: bcrypt.MinCost,
 	})
 	if err != nil {
 		t.Fatalf("new database: %v", err)
@@ -134,7 +145,7 @@ func newTestEnvWithResolver(
 	))
 
 	srv := ircserver.NewTestServer(
-		log, cfg, database, brk, interval, deadline, resolve,
+		log, cfg, database, brk, interval, deadline, poll, resolve,
 	)
 
 	// Port 0 makes the system pick a free port. dial reads it
@@ -430,7 +441,8 @@ func TestRegistrationWhileAnotherLookupIsPending(t *testing.T) {
 
 	env := newTestEnvWithResolver(
 		t, &config.Config{ServerName: testServerName},
-		ircserver.PingInterval, ircserver.PongDeadline, resolve,
+		ircserver.PingInterval, ircserver.PongDeadline,
+		testPollInterval, resolve,
 	)
 
 	env.dial(t)
@@ -1039,12 +1051,16 @@ func TestStopEndsSessions(t *testing.T) {
 }
 
 // TestStopReturnsWhileCleanupIsStuck checks that Stop stops
-// waiting for a connection's cleanup after StopTimeout, so a
+// waiting for a connection's cleanup after its stop timeout,
-// cleanup that cannot finish does not hold up stopping.
+// so a cleanup that cannot finish does not hold up stopping.
 func TestStopReturnsWhileCleanupIsStuck(t *testing.T) {
 	t.Parallel()
 
+	const stopTimeout = 100 * time.Millisecond
+
 	env := newTestEnv(t)
+	env.srv.SetStopTimeout(stopTimeout)
+
 	client := env.dial(t)
 
 	client.register("stuck")
@@ -1070,7 +1086,7 @@ func TestStopReturnsWhileCleanupIsStuck(t *testing.T) {
 
 	select {
 	case <-stopped:
-	case <-time.After(ircserver.StopTimeout + testTimeout):
+	case <-time.After(stopTimeout + testTimeout):
 		t.Error("Stop did not return while a cleanup was stuck")
 	}
 
@@ -1122,9 +1138,6 @@ func TestDirectMessage(t *testing.T) {
 	receiver := env.dial(t)
 	receiver.register("dmreceiver")
 
-	// Give relay goroutines time to start.
-	time.Sleep(100 * time.Millisecond)
-
 	sender.send("PRIVMSG dmreceiver :hello privately")
 
 	lines := receiver.readUntil(func(line string) bool {

internal/service/service_test.go

@@ -1,7 +1,3 @@
-// Tests use a global viper instance for configuration,
-// making parallel execution unsafe.
-//
-//nolint:paralleltest
 package service_test
 
 import (
@@ -59,28 +55,12 @@ func newTestEnv(t *testing.T) *testEnv {
 				}
 			},
 			logger.New,
-			func(
+			func() *config.Config {
-				lifecycle fx.Lifecycle,
+				return &config.Config{
-				globs *globals.Globals,
+					DBURL:        dbURL,
-				log *logger.Logger,
+					OperName:     "admin",
-			) (*config.Config, error) {
+					OperPassword: "secret",
-				cfg, err := config.New(
-					lifecycle, config.Params{ //nolint:exhaustruct
-						Globals: globs, Logger: log,
-					},
-				)
-				if err != nil {
-					return nil, fmt.Errorf(
-						"test config: %w", err,
-					)
 				}
-
-				cfg.DBURL = dbURL
-				cfg.Port = 0
-				cfg.OperName = "admin"
-				cfg.OperPassword = "secret"
-
-				return cfg, nil
 			},
 			func(
 				lifecycle fx.Lifecycle,
@@ -136,6 +116,8 @@ func createSession(
 // environment starts on an empty database while another one
 // is still open.
 func TestEachTestEnvHasItsOwnDatabase(t *testing.T) {
+	t.Parallel()
+
 	ctx := t.Context()
 
 	first := newTestEnv(t)
@@ -146,6 +128,8 @@ func TestEachTestEnvHasItsOwnDatabase(t *testing.T) {
 }
 
 func TestFanOut(t *testing.T) {
+	t.Parallel()
+
 	env := newTestEnv(t)
 	ctx := t.Context()
 
@@ -173,6 +157,8 @@ func TestFanOut(t *testing.T) {
 }
 
 func TestJoinChannel(t *testing.T) {
+	t.Parallel()
+
 	env := newTestEnv(t)
 	ctx := t.Context()
 
@@ -213,6 +199,8 @@ func TestJoinChannel(t *testing.T) {
 }
 
 func TestPartChannel(t *testing.T) {
+	t.Parallel()
+
 	env := newTestEnv(t)
 	ctx := t.Context()
 
@@ -313,6 +301,8 @@ func joinConcurrently(
 // concurrent JOINs of a +l 2 channel with one member, one
 // gets in and the other gets ERR_CHANNELISFULL.
 func TestConcurrentJoinsRespectUserLimit(t *testing.T) {
+	t.Parallel()
+
 	const userLimit = 2
 
 	env := newTestEnv(t)
@@ -375,6 +365,8 @@ func TestConcurrentJoinsRespectUserLimit(t *testing.T) {
 // two concurrent JOINs that create a channel, exactly one
 // makes its session the operator.
 func TestConcurrentFirstJoinsMakeOneOperator(t *testing.T) {
+	t.Parallel()
+
 	env := newTestEnv(t)
 	ctx := t.Context()
 
@@ -426,6 +418,8 @@ func TestConcurrentFirstJoinsMakeOneOperator(t *testing.T) {
 // either joins a channel that still exists or gets
 // ERR_NOSUCHCHANNEL, and never fails otherwise.
 func TestJoinConcurrentWithLastPart(t *testing.T) {
+	t.Parallel()
+
 	env := newTestEnv(t)
 	ctx := t.Context()
 
@@ -491,6 +485,8 @@ func TestJoinConcurrentWithLastPart(t *testing.T) {
 // quits, gets in only once the channel is deleted, into a
 // new channel of that name with no key.
 func TestJoinConcurrentWithLastQuit(t *testing.T) {
+	t.Parallel()
+
 	env := newTestEnv(t)
 	ctx := t.Context()
 
@@ -569,81 +565,95 @@ const quitCrowdSize = 10
 // ahead of that JOIN. The quitting session is also on a
 // channel with quitCrowdSize other sessions, made before the
 // watcher's channel, so that its QUIT reaches the watcher
-// last.
+// last. Each trial runs on a database of its own.
 func TestQuitQueuedAheadOfNewNickHoldersJoin(t *testing.T) {
-	env := newTestEnv(t)
+	t.Parallel()
-	ctx := t.Context()
 
 	for trial := range concurrentJoinTrials {
-		nick := fmt.Sprintf("reused%d", trial)
+		t.Run(fmt.Sprintf("trial %d", trial), func(t *testing.T) {
-		crowd := fmt.Sprintf("#crowd%d", trial)
+			t.Parallel()
-		shared := fmt.Sprintf("#shared%d", trial)
-		quitterSID := createSession(ctx, t, env.db, nick)
 
-		for _, channel := range []string{crowd, shared} {
+			checkQuitQueuedAheadOfJoin(t, newTestEnv(t))
-			_, err := env.svc.JoinChannel(ctx, quitterSID, 0, nick, channel, "")
+		})
-			if err != nil {
+	}
-				t.Fatalf("join %s: %v", channel, err)
+}
-			}
+
+// checkQuitQueuedAheadOfJoin runs one trial of
+// TestQuitQueuedAheadOfNewNickHoldersJoin on env.
+func checkQuitQueuedAheadOfJoin(t *testing.T, env *testEnv) {
+	t.Helper()
+
+	const (
+		nick        = "reused"
+		crowd       = "#crowd"
+		shared      = "#shared"
+		watcherNick = "watcher"
+	)
+
+	ctx := t.Context()
+	quitterSID := createSession(ctx, t, env.db, nick)
+
+	for _, channel := range []string{crowd, shared} {
+		_, err := env.svc.JoinChannel(ctx, quitterSID, 0, nick, channel, "")
+		if err != nil {
+			t.Fatalf("join %s: %v", channel, err)
 		}
+	}
 
-		for member := range quitCrowdSize {
+	for member := range quitCrowdSize {
-			memberNick := fmt.Sprintf("crowd%dx%d", trial, member)
+		memberNick := fmt.Sprintf("crowd%d", member)
-			memberSID := createSession(ctx, t, env.db, memberNick)
+		memberSID := createSession(ctx, t, env.db, memberNick)
 
-			_, err := env.svc.JoinChannel(ctx, memberSID, 0, memberNick, crowd, "")
+		_, err := env.svc.JoinChannel(ctx, memberSID, 0, memberNick, crowd, "")
-			if err != nil {
+		if err != nil {
-				t.Fatalf("join %s: %v", memberNick, err)
+			t.Fatalf("join %s: %v", memberNick, err)
-			}
 		}
+	}
 
-		watcherNick := fmt.Sprintf("watcher%d", trial)
+	watcherSID, watcherClientID, _, err := env.db.CreateSession(
+		ctx, watcherNick, watcherNick, "localhost", "127.0.0.1",
+	)
+	if err != nil {
+		t.Fatalf("create session %s: %v", watcherNick, err)
+	}
 
-		watcherSID, watcherClientID, _, err := env.db.CreateSession(
+	_, err = env.svc.JoinChannel(ctx, watcherSID, 0, watcherNick, shared, "")
-			ctx, watcherNick, watcherNick, "localhost", "127.0.0.1",
+	if err != nil {
+		t.Fatalf("join %s: %v", watcherNick, err)
+	}
+
+	_, lastQueueID, err := env.db.PollMessages(ctx, watcherClientID, 0, 0)
+	if err != nil {
+		t.Fatalf("poll: %v", err)
+	}
+
+	errs := runConcurrently(
+		func() error {
+			env.svc.BroadcastQuit(ctx, quitterSID, nick, "")
+
+			return nil
+		},
+		func() error {
+			return takeNickAndJoin(ctx, env, nick, shared)
+		},
+	)
+	if errs[1] != nil {
+		t.Fatalf("new session: %v", errs[1])
+	}
+
+	msgs, _, err := env.db.PollMessages(
+		ctx, watcherClientID, lastQueueID, 0,
+	)
+	if err != nil {
+		t.Fatalf("poll: %v", err)
+	}
+
+	commands := commandsFrom(msgs, nick)
+	if !slices.Equal(commands, []string{irc.CmdQuit, irc.CmdJoin}) {
+		t.Errorf(
+			"watcher got %v from %s, want QUIT then JOIN",
+			commands, nick,
 		)
-		if err != nil {
-			t.Fatalf("create session %s: %v", watcherNick, err)
-		}
-
-		_, err = env.svc.JoinChannel(ctx, watcherSID, 0, watcherNick, shared, "")
-		if err != nil {
-			t.Fatalf("join %s: %v", watcherNick, err)
-		}
-
-		_, lastQueueID, err := env.db.PollMessages(ctx, watcherClientID, 0, 0)
-		if err != nil {
-			t.Fatalf("poll: %v", err)
-		}
-
-		errs := runConcurrently(
-			func() error {
-				env.svc.BroadcastQuit(ctx, quitterSID, nick, "")
-
-				return nil
-			},
-			func() error {
-				return takeNickAndJoin(ctx, env, nick, shared)
-			},
-		)
-		if errs[1] != nil {
-			t.Fatalf("trial %d: new session: %v", trial, errs[1])
-		}
-
-		msgs, _, err := env.db.PollMessages(
-			ctx, watcherClientID, lastQueueID, 0,
-		)
-		if err != nil {
-			t.Fatalf("poll: %v", err)
-		}
-
-		commands := commandsFrom(msgs, nick)
-		if !slices.Equal(commands, []string{irc.CmdQuit, irc.CmdJoin}) {
-			t.Errorf(
-				"trial %d: watcher got %v from %s, want QUIT then JOIN",
-				trial, commands, nick,
-			)
-		}
 	}
 }
 
@@ -691,6 +701,8 @@ func commandsFrom(msgs []db.IRCMessage, nick string) []string {
 // into a +i channel uses the invite up, so that a JOIN
 // after leaving gets ERR_INVITEONLYCHAN.
 func TestJoinUsesUpInvite(t *testing.T) {
+	t.Parallel()
+
 	const channel = "#club"
 
 	env := newTestEnv(t)
@@ -736,6 +748,8 @@ func TestJoinUsesUpInvite(t *testing.T) {
 // session's nick, username and hostname refuses its JOIN
 // with ERR_BANNEDFROMCHAN.
 func TestJoinRefusedByHostmaskBan(t *testing.T) {
+	t.Parallel()
+
 	const channel = "#club"
 
 	env := newTestEnv(t)
@@ -774,6 +788,8 @@ func TestJoinRefusedByHostmaskBan(t *testing.T) {
 // keeps a channel other members are still on and deletes
 // the channel when its last member parts.
 func TestPartDeletesChannelOnlyWhenEmpty(t *testing.T) {
+	t.Parallel()
+
 	const channel = "#room"
 
 	env := newTestEnv(t)
@@ -821,6 +837,8 @@ func TestPartDeletesChannelOnlyWhenEmpty(t *testing.T) {
 // TestKickOfLastMemberDeletesChannel checks that a KICK
 // that leaves a channel with no members deletes it.
 func TestKickOfLastMemberDeletesChannel(t *testing.T) {
+	t.Parallel()
+
 	const channel = "#room"
 
 	env := newTestEnv(t)
@@ -845,6 +863,8 @@ func TestKickOfLastMemberDeletesChannel(t *testing.T) {
 }
 
 func TestSendChannelMessage(t *testing.T) {
+	t.Parallel()
+
 	env := newTestEnv(t)
 	ctx := t.Context()
 
@@ -892,6 +912,8 @@ func TestSendChannelMessage(t *testing.T) {
 }
 
 func TestBroadcastQuit(t *testing.T) {
+	t.Parallel()
+
 	env := newTestEnv(t)
 	ctx := t.Context()
 
@@ -929,6 +951,8 @@ func TestBroadcastQuit(t *testing.T) {
 // error as a DM to an unknown nick. The trigger deletes the
 // target's session just before the DM is stored.
 func TestSendDirectMessageTargetQuits(t *testing.T) {
+	t.Parallel()
+
 	env := newTestEnv(t)
 	ctx := t.Context()
 
@@ -960,6 +984,8 @@ func TestSendDirectMessageTargetQuits(t *testing.T) {
 // trigger deletes the channel just before the message is
 // stored.
 func TestSendChannelMessageChannelDeleted(t *testing.T) {
+	t.Parallel()
+
 	env := newTestEnv(t)
 	ctx := t.Context()
 
@@ -991,6 +1017,8 @@ func TestSendChannelMessageChannelDeleted(t *testing.T) {
 }
 
 func TestSendChannelMessage_Moderated(t *testing.T) {
+	t.Parallel()
+
 	env := newTestEnv(t)
 	ctx := t.Context()
 
@@ -1042,6 +1070,8 @@ func TestSendChannelMessage_Moderated(t *testing.T) {
 // not spend its hashcash stamp: the operator can then send
 // the same message with it.
 func TestRefusedChannelMessageLeavesStampUnspent(t *testing.T) {
+	t.Parallel()
+
 	const (
 		channel = "#paid"
 		bits    = 2
@@ -1067,6 +1097,8 @@ func TestRefusedChannelMessageLeavesStampUnspent(t *testing.T) {
 
 	for _, refusal := range refusals {
 		t.Run(refusal.name, func(t *testing.T) {
+			t.Parallel()
+
 			env := newTestEnv(t)
 			ctx := t.Context()
 
@@ -1119,6 +1151,8 @@ func TestRefusedChannelMessageLeavesStampUnspent(t *testing.T) {
 }
 
 func TestQueryUserMode(t *testing.T) {
+	t.Parallel()
+
 	env := newTestEnv(t)
 	ctx := t.Context()
 
@@ -1169,6 +1203,8 @@ func TestQueryUserMode(t *testing.T) {
 }
 
 func TestUserhostReply(t *testing.T) {
+	t.Parallel()
+
 	env := newTestEnv(t)
 	ctx := t.Context()
 
@@ -1274,10 +1310,14 @@ func applyUserModeTests() []applyUserModeTest {
 }
 
 func TestApplyUserMode(t *testing.T) {
+	t.Parallel()
+
 	env := newTestEnv(t)
 
 	for i, test := range applyUserModeTests() {
 		t.Run(test.modeStr, func(t *testing.T) {
+			t.Parallel()
+
 			ctx := t.Context()
 			sid := createSession(
 				ctx, t, env.db, fmt.Sprintf("user%d", i),