message: fix, rings must have at least three elements
diff: @@ -142,7 +142,11 @@ function addRing(state: State, a: number, b: number) {
  if (current < 0) break;
  }
  - const ring = new Int32Array(leftOffset + rightOffset);
  + const len = leftOffset + rightOffset
  + // rings must have at least three elements
  + if (len < 3) return
  +
  + const ring = new Int32Array(len);
  let ringOffset = 0;
  for (let t = 0; t < leftOffset; t++) ring[ringOffset++] = state.startVertex + left[t];
  for (let t = rightOffset - 1; t >= 0; t--) ring[ringOffset++] = state.startVertex + right[t];
  