1 files changed, 49 insertions, 0 deletions
diff --git a/internal/database/pool_test.go b/internal/database/pool_test.go
new file mode 100644
index 00000000..06fa048d
--- /dev/null
+++ b/internal/database/pool_test.go
@@ -0,0 +1,49 @@
+// Copyright 2026 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package database
+
+import (
+	"database/sql"
+	"testing"
+	"time"
+)
+
+func TestSetPoolSettings(t *testing.T) {
+	// We use an empty DSN which the driver might reject, but sql.Open does not
+	// actually connect or ping.
+	sdb, err := sql.Open("postgres", "postgres://localhost/test?sslmode=disable")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer sdb.Close()
+
+	db := New(sdb, "test")
+
+	t.Run("valid settings", func(t *testing.T) {
+		maxOpen := 42
+		maxIdle := 13
+		maxLifetime := 10 * time.Minute
+		maxIdleTime := 5 * time.Minute
+
+		db.SetPoolSettings(maxOpen, maxIdle, maxLifetime, maxIdleTime)
+
+		stats := db.Underlying().Stats()
+		if stats.MaxOpenConnections != maxOpen {
+			t.Errorf("got %d, want %d", stats.MaxOpenConnections, maxOpen)
+		}
+	})
+
+	t.Run("maxIdle > maxOpen", func(t *testing.T) {
+		maxOpen := 10
+		maxIdle := 20
+		maxLifetime := 10 * time.Minute
+		maxIdleTime := 5 * time.Minute
+
+		// This should log a warning and cap maxIdle to maxOpen.
+		db.SetPoolSettings(maxOpen, maxIdle, maxLifetime, maxIdleTime)
+
+		// We can't easily check internal sql.DB settings, but we verify it doesn't crash.
+	})
+}