1 files changed, 53 insertions, 0 deletions
diff --git a/internal/engine/session_test.go b/internal/engine/session_test.go
index 5cab274..750fa04 100644
--- a/internal/engine/session_test.go
+++ b/internal/engine/session_test.go
@@ -270,3 +270,56 @@ func TestSessionDropsUnappliedClaims(t *testing.T) {
 		t.Errorf("beta planned %q; the declined destination should be free", got)
 	}
 }
+
+// TestNowIsTheStartOfTheRun: {now:FMT} is documented as "the start of the
+// run" (spec §7.3), and the plan a user approves must not change under
+// them. Reading the clock once per directory put one run's files into two
+// folders when the review took a moment - across midnight, two dates.
+func TestNowIsTheStartOfTheRun(t *testing.T) {
+	h := sandbox(t)
+	dl := filepath.Join(h, "dl")
+	old := time.Date(2026, 1, 1, 0, 0, 0, 0, time.UTC)
+	for _, n := range []string{"a.pdf", "b.pdf"} {
+		p := filepath.Join(dl, n)
+		if err := os.MkdirAll(filepath.Dir(p), 0o755); err != nil {
+			t.Fatal(err)
+		}
+		if err := os.WriteFile(p, []byte("x"), 0o644); err != nil {
+			t.Fatal(err)
+		}
+		if err := os.Chtimes(p, old, old); err != nil {
+			t.Fatal(err)
+		}
+	}
+	conf := "(path \"~/dl\")\n(min-age 0s)\n(rule \"stamp\" (move \"Out/{now:%H%M%S}\"))\n"
+	main := writeConfig(t, h, `(include "dl")`, map[string]string{"dl": conf})
+	e, errs := Load(main)
+	if len(errs) > 0 {
+		t.Fatal(errs)
+	}
+	// A clock that moves on every reading, as a review pause does.
+	tick := time.Date(2026, 9, 17, 23, 59, 59, 0, time.UTC)
+	e.Now = func() time.Time {
+		tick = tick.Add(3 * time.Second)
+		return tick
+	}
+
+	sess, err := e.NewSession(true)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer sess.Close()
+	first, err := sess.Plan(context.Background(), e.Dirs[0])
+	if err != nil {
+		t.Fatal(err)
+	}
+	second, err := sess.Plan(context.Background(), e.Dirs[0])
+	if err != nil {
+		t.Fatal(err)
+	}
+	a := filepath.Dir(first.Chains[0].Steps[0].Dst)
+	b := filepath.Dir(second.Chains[0].Steps[0].Dst)
+	if a != b {
+		t.Errorf("one run stamped two different folders: %s and %s", a, b)
+	}
+}