1 files changed, 72 insertions, 0 deletions
diff --git a/internal/game/hardening_casino_entropy_wiring_test.go b/internal/game/hardening_casino_entropy_wiring_test.go
new file mode 100644
index 0000000..4f7c75e
--- /dev/null
+++ b/internal/game/hardening_casino_entropy_wiring_test.go
@@ -0,0 +1,72 @@
+package game
+
+// Closure regressions for the casino RNG hardening: the entropy-seeded
+// constructor must be the one PRODUCTION wires, not merely available.
+
+import (
+	"io/fs"
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+)
+
+// TestProductionCasinoSeedIsEntropy pins the production wiring: game.New must
+// build its casino manager with casino.NewManagerEntropy, and no production
+// file may call casino.NewManager(seed). That constructor exists only as the
+// deterministic test seam, because a wall-clock seed makes every shoe, reel,
+// and spin stream reconstructible from the startup nanosecond.
+//
+// The manager's seed is unexported and deliberately not observable through the
+// casino API (NewManagerEntropy and NewManager are otherwise
+// indistinguishable), so this is a source-level guard: it is the only place
+// the choice of constructor can be pinned. It fails on a revert to
+// NewManager(time.Now().UnixNano()).
+func TestProductionCasinoSeedIsEntropy(t *testing.T) {
+	root := filepath.Join("..", "..")
+	sawEntropyCall := false
+	err := filepath.WalkDir(root, func(path string, d fs.DirEntry, err error) error {
+		if err != nil {
+			return err
+		}
+		if d.IsDir() {
+			name := d.Name()
+			// Skip VCS internals, generated/test data, and the persisted
+			// game data (which is not Go source at all).
+			if path != root && (strings.HasPrefix(name, ".") || name == "testdata" || name == "vendor") {
+				return fs.SkipDir
+			}
+			return nil
+		}
+		if !strings.HasSuffix(d.Name(), ".go") || strings.HasSuffix(d.Name(), "_test.go") {
+			return nil
+		}
+		data, readErr := os.ReadFile(path)
+		if readErr != nil {
+			return readErr
+		}
+		rel, relErr := filepath.Rel(root, path)
+		if relErr != nil {
+			rel = path
+		}
+		for i, line := range strings.Split(string(data), "\n") {
+			trimmed := strings.TrimSpace(line)
+			if strings.HasPrefix(trimmed, "//") || strings.HasPrefix(trimmed, "*") {
+				continue // prose about the seam, not a call
+			}
+			if strings.Contains(trimmed, "casino.NewManager(") {
+				t.Errorf("%s:%d calls the deterministic casino.NewManager(seed) outside tests: %s", rel, i+1, trimmed)
+			}
+			if strings.Contains(trimmed, "casino.NewManagerEntropy()") {
+				sawEntropyCall = true
+			}
+		}
+		return nil
+	})
+	if err != nil {
+		t.Fatalf("walk module: %v", err)
+	}
+	if !sawEntropyCall {
+		t.Fatal("no production call to casino.NewManagerEntropy() found: the casino RNG entropy fix is not wired")
+	}
+}