( oldTree: Node, newTree: IRRNode, replayer: ReplayerHandler, rrnodeMirror: Mirror, )
| 371 | } |
| 372 | |
| 373 | function diffChildren( |
| 374 | oldTree: Node, |
| 375 | newTree: IRRNode, |
| 376 | replayer: ReplayerHandler, |
| 377 | rrnodeMirror: Mirror, |
| 378 | ) { |
| 379 | const oldChildren: (Node | undefined)[] = Array.from(oldTree.childNodes); |
| 380 | const newChildren = newTree.childNodes; |
| 381 | if (oldChildren.length === 0 && newChildren.length === 0) return; |
| 382 | let oldStartIndex = 0, |
| 383 | oldEndIndex = oldChildren.length - 1, |
| 384 | newStartIndex = 0, |
| 385 | newEndIndex = newChildren.length - 1; |
| 386 | let oldStartNode = oldChildren[oldStartIndex], |
| 387 | oldEndNode = oldChildren[oldEndIndex], |
| 388 | newStartNode = newChildren[newStartIndex], |
| 389 | newEndNode = newChildren[newEndIndex]; |
| 390 | let oldIdToIndex: Record<number, number> | undefined = undefined, |
| 391 | indexInOld: number | undefined = undefined; |
| 392 | while (oldStartIndex <= oldEndIndex && newStartIndex <= newEndIndex) { |
| 393 | if (oldStartNode === undefined) { |
| 394 | oldStartNode = oldChildren[++oldStartIndex]; |
| 395 | } else if (oldEndNode === undefined) { |
| 396 | oldEndNode = oldChildren[--oldEndIndex]; |
| 397 | } else if ( |
| 398 | // same first node? |
| 399 | nodeMatching(oldStartNode, newStartNode, replayer.mirror, rrnodeMirror) |
| 400 | ) { |
| 401 | oldStartNode = oldChildren[++oldStartIndex]; |
| 402 | newStartNode = newChildren[++newStartIndex]; |
| 403 | } else if ( |
| 404 | // same last node? |
| 405 | nodeMatching(oldEndNode, newEndNode, replayer.mirror, rrnodeMirror) |
| 406 | ) { |
| 407 | oldEndNode = oldChildren[--oldEndIndex]; |
| 408 | newEndNode = newChildren[--newEndIndex]; |
| 409 | } else if ( |
| 410 | // is the first old node the same as the last new node? |
| 411 | nodeMatching(oldStartNode, newEndNode, replayer.mirror, rrnodeMirror) |
| 412 | ) { |
| 413 | try { |
| 414 | oldTree.insertBefore(oldStartNode, oldEndNode.nextSibling); |
| 415 | } catch (e) { |
| 416 | console.warn(e); |
| 417 | } |
| 418 | oldStartNode = oldChildren[++oldStartIndex]; |
| 419 | newEndNode = newChildren[--newEndIndex]; |
| 420 | } else if ( |
| 421 | // is the last old node the same as the first new node? |
| 422 | nodeMatching(oldEndNode, newStartNode, replayer.mirror, rrnodeMirror) |
| 423 | ) { |
| 424 | try { |
| 425 | oldTree.insertBefore(oldEndNode, oldStartNode); |
| 426 | } catch (e) { |
| 427 | console.warn(e); |
| 428 | } |
| 429 | oldEndNode = oldChildren[--oldEndIndex]; |
| 430 | newStartNode = newChildren[++newStartIndex]; |
no test coverage detected