Stop the slow test packages waiting (closes #263)

The slowest test packages spent their time waiting rather than testing.

db.Params gains an optional PasswordCost (zero means bcrypt.DefaultCost), and the db, ircserver and handlers tests hash at bcrypt.MinCost. A test IRC server's relay checks its queue on broker notification instead of polling. The service and handlers tests build config.Config directly and run in parallel; config exports DefaultTrustedProxies and ParseTrustedProxies for them. Fixed sleeps give way to waits for the event. Production defaults are unchanged.

What still takes time is CPU work under -race or a timeout a test is about.

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
-	log    *slog.Logger
-	params *Params
+	conn         *sql.DB
+	log          *slog.Logger
+	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,
-		log:    params.Logger.Get(),
+		params:       &params,
+		log:          params.Logger.Get(),
+		passwordCost: passwordCost,
 	}
 
 	database.log.Info("Database instantiated")

internal/db/db_test.go

@@ -10,6 +10,7 @@ import (
 	"time"
 
 	"go.uber.org/fx/fxtest"
+	"golang.org/x/crypto/bcrypt"
 	"sneak.berlin/go/neoirc/internal/config"
 	"sneak.berlin/go/neoirc/internal/db"
 	"sneak.berlin/go/neoirc/internal/dbtest"
@@ -240,6 +241,85 @@ func TestDBURLSettingForeignKeysFailsStartup(t *testing.T) {
 	}
 }
 
+// TestPasswordCost checks the bcrypt cost of the hash that SetPassword
+// stores: bcrypt.DefaultCost when db.Params leaves PasswordCost unset,
+// as the server does, and PasswordCost when it is set.
+func TestPasswordCost(t *testing.T) {
+	t.Parallel()
+
+	tests := []struct {
+		name         string
+		passwordCost int
+		wantCost     int
+	}{
+		{name: "unset", wantCost: bcrypt.DefaultCost},
+		{
+			name:         "bcrypt.MinCost",
+			passwordCost: bcrypt.MinCost,
+			wantCost:     bcrypt.MinCost,
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			t.Parallel()
+
+			lifecycle := fxtest.NewLifecycle(t)
+
+			log, err := logger.New(lifecycle, logger.Params{
+				Globals: &globals.Globals{},
+			})
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			database, err := db.New(lifecycle, db.Params{
+				Logger:       log,
+				Config:       &config.Config{DBURL: dbtest.NewURL(t)},
+				PasswordCost: test.passwordCost,
+			})
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			lifecycle.RequireStart()
+			t.Cleanup(lifecycle.RequireStop)
+
+			sessionID, _, _, err := database.CreateSession(
+				t.Context(), "costuser", "", "", "",
+			)
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			err = database.SetPassword(t.Context(), sessionID, "password123")
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			var hash string
+
+			err = database.GetDB().QueryRowContext(
+				t.Context(),
+				"SELECT password_hash FROM sessions WHERE id = ?",
+				sessionID,
+			).Scan(&hash)
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			cost, err := bcrypt.Cost([]byte(hash))
+			if err != nil {
+				t.Fatal(err)
+			}
+
+			if cost != test.wantCost {
+				t.Errorf("cost = %d, want %d", cost, test.wantCost)
+			}
+		})
+	}
+}
+
 // startDatabase starts a Database for dbURL the way the server does.
 // It returns the error that stopped it from starting, if any.
 func startDatabase(t *testing.T, dbURL string) (*db.Database, error) {

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,
-		log:  slog.Default(),
+		conn:         conn,
+		log:          slog.Default(),
+		passwordCost: bcrypt.MinCost,
 	}
 
 	err = database.runMigrations(context.Background())