test public directly

cmd/server/main_test.go

@@ -41,3 +41,11 @@ func TestRunHTTP(t *testing.T) {
 		}
 	})
 }
+
+func TestPublic(t *testing.T) {
+	f, err := public.Open("index.html")
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer f.Close()
+}