perf(vom): optimize rendering algorithms

packages/vom/src/__tests__/render.test.ts

@@ -298,6 +298,34 @@ describe("renderVom single-layer page", () => {
     expect(coreRefs(out.refs)).toEqual([{ ref: "e1", backendNodeId: 4 }]);
   });
 
+  it("renders through deeply nested transparent wrappers without exhausting the call stack", () => {
+    const wrapperCount = 10_000;
+    const nodes = [node({ id: 1, role: "RootWebArea", name: "Doc" })];
+    for (let index = 0; index < wrapperCount; index += 1) {
+      nodes.push(
+        node({
+          id: index + 2,
+          parentId: index + 1,
+          role: "generic",
+        }),
+      );
+    }
+    nodes.push(
+      node({
+        id: wrapperCount + 2,
+        parentId: wrapperCount + 1,
+        role: "button",
+        name: "Deep action",
+        tag: "button",
+      }),
+    );
+
+    const out = renderVom(scene(nodes));
+
+    expect(out.text).toContain('@e1 button "Deep action"');
+    expect(coreRefs(out.refs)).toEqual([{ ref: "e1", backendNodeId: wrapperCount + 2 }]);
+  });
+
   it("truncates when maxTokens is exceeded while keeping refs in sync with rendered text", () => {
     const out = renderVom(
       scene([
@@ -785,6 +813,55 @@ describe("renderVom single-layer page", () => {
     expect(out.text).not.toContain("北京市小客车指标调控管理信息系统]");
   });
 
+  it("derives duplicate-label context from indexed DOM ancestry without semantic proximity", () => {
+    const out = renderVom(
+      scene([
+        node({ id: 1, role: "RootWebArea", name: "Doc", contextScopeId: "root" }),
+        node({
+          id: 3,
+          parentId: 1,
+          role: "button",
+          name: "View",
+          tag: "button",
+          domParentId: 2,
+          domAncestorIds: [2, 1],
+          contextScopeId: "root",
+        }),
+        node({
+          id: 5,
+          parentId: 1,
+          role: "button",
+          name: "View",
+          tag: "button",
+          domParentId: 4,
+          domAncestorIds: [4, 1],
+          contextScopeId: "root",
+        }),
+        node({
+          id: 2,
+          parentId: 1,
+          role: "group",
+          name: "Project Alpha",
+          domParentId: 1,
+          domAncestorIds: [1],
+          contextScopeId: "root",
+        }),
+        node({
+          id: 4,
+          parentId: 1,
+          role: "group",
+          name: "Project Beta",
+          domParentId: 1,
+          domAncestorIds: [1],
+          contextScopeId: "root",
+        }),
+      ]),
+    );
+
+    expect(out.text).toContain('@e1 button "View" [ctx: Project Alpha]');
+    expect(out.text).toContain('@e2 button "View" [ctx: Project Beta]');
+  });
+
   it("does not add low-value root context to duplicated brand links", () => {
     const out = renderVom(
       scene([
@@ -833,6 +910,34 @@ describe("renderVom single-layer page", () => {
 });
 
 describe("renderVom double-layer page", () => {
+  it("collects blocking-layer descendants even when children precede parents in source order", () => {
+    const out = renderVom(
+      scene([
+        node({ id: 1, role: "RootWebArea", name: "Doc" }),
+        node({
+          id: 3,
+          parentId: 2,
+          role: "button",
+          name: "Close",
+          tag: "button",
+          paintOrder: 0,
+        }),
+        node({
+          id: 2,
+          parentId: 1,
+          role: "dialog",
+          name: "Modal",
+          rect: { x: 0, y: 0, w: 1280, h: 720 },
+          paintOrder: 10,
+          position: "fixed",
+        }),
+      ]),
+    );
+
+    expect(out.text).toContain('@e1 button "Close"');
+    expect(coreRefs(out.refs)).toEqual([{ ref: "e1", backendNodeId: 3 }]);
+  });
+
   it("renders a blocking modal first and folds the base page into an occluded summary", () => {
     const out = renderVom(
       scene([

packages/vom/src/render.ts

@@ -421,6 +421,41 @@ function buildChildren(nodes: VomNode[]): Map<number | null, VomNode[]> {
   return children;
 }
 
+const CONTEXT_LABEL_ROLES = new Set([
+  "heading",
+  "article",
+  "section",
+  "group",
+  "region",
+  "row",
+  "form",
+]);
+
+interface DomContextIndex {
+  nonBoundaryByScopeParent: Map<string | undefined, Map<number, VomNode[]>>;
+  sourceOrderById: Map<number, number>;
+}
+
+function buildDomContextIndex(nodes: VomNode[]): DomContextIndex {
+  const nonBoundaryByScopeParent = new Map<string | undefined, Map<number, VomNode[]>>();
+  const sourceOrderById = new Map<number, number>();
+  for (const [sourceOrder, node] of nodes.entries()) {
+    sourceOrderById.set(node.id, sourceOrder);
+    if (!CONTEXT_LABEL_ROLES.has(normalizedRole(node)) || isContextBoundary(node)) continue;
+    const parentId = node.domParentId;
+    if (parentId === undefined || parentId === null) continue;
+    let byParent = nonBoundaryByScopeParent.get(node.contextScopeId);
+    if (!byParent) {
+      byParent = new Map();
+      nonBoundaryByScopeParent.set(node.contextScopeId, byParent);
+    }
+    const siblings = byParent.get(parentId) ?? [];
+    siblings.push(node);
+    byParent.set(parentId, siblings);
+  }
+  return { nonBoundaryByScopeParent, sourceOrderById };
+}
+
 function duplicateReferenceNames(nodes: VomNode[]): Set<string> {
   const counts = new Map<string, number>();
   for (const node of nodes) {
@@ -440,13 +475,7 @@ function needsHandleContext(nodeName: string, duplicateRefNames: Set<string>): b
 }
 
 function contextLabel(node: VomNode, targetName: string): string | undefined {
-  if (
-    !["heading", "article", "section", "group", "region", "row", "form"].includes(
-      normalizedRole(node),
-    )
-  ) {
-    return undefined;
-  }
+  if (!CONTEXT_LABEL_ROLES.has(normalizedRole(node))) return undefined;
   return weakContextText(
     cleaned(node.name) ?? cleaned(node.text) ?? cleaned(node.nearbyText),
     targetName,
@@ -607,19 +636,45 @@ function collectDomContext(
 ): ContextCandidate[] {
   const ancestorIds = node.domAncestorIds ?? [];
   if (ancestorIds.length === 0) return [];
-  const ancestors = new Set(ancestorIds);
   const contexts: ContextCandidate[] = [];
+  const ancestorRank = new Map<number, number>();
+  for (const [rank, ancestorId] of ancestorIds.entries()) {
+    if (!ancestorRank.has(ancestorId)) ancestorRank.set(ancestorId, rank);
+  }
 
-  for (const candidate of state.nodesById.values()) {
+  const candidates = new Map<number, VomNode>();
+  const nonBoundaryByParent = state.domContextIndex.nonBoundaryByScopeParent.get(
+    node.contextScopeId,
+  );
+  for (const ancestorId of ancestorRank.keys()) {
+    const boundary = state.nodesById.get(ancestorId);
+    const boundaryParentId = boundary?.domParentId;
+    if (
+      boundary &&
+      sharesContextScope(node, boundary) &&
+      isContextBoundary(boundary) &&
+      boundaryParentId !== undefined &&
+      boundaryParentId !== null &&
+      ancestorRank.has(boundaryParentId)
+    ) {
+      candidates.set(boundary.id, boundary);
+    }
+    for (const candidate of nonBoundaryByParent?.get(ancestorId) ?? []) {
+      candidates.set(candidate.id, candidate);
+    }
+  }
+
+  const sourceOrderById = state.domContextIndex.sourceOrderById;
+  const orderedCandidates = [...candidates.values()].sort(
+    (a, b) => (sourceOrderById.get(a.id) ?? 0) - (sourceOrderById.get(b.id) ?? 0),
+  );
+  for (const candidate of orderedCandidates) {
     if (candidate.id === node.id) continue;
-    if (!sharesContextScope(node, candidate)) continue;
-    if (isContextBoundary(candidate) && !ancestorIds.includes(candidate.id)) continue;
     const parentId = candidate.domParentId;
-    if (parentId === undefined || parentId === null || !ancestors.has(parentId)) continue;
+    if (parentId === undefined || parentId === null) continue;
     const label = contextLabel(candidate, nodeName);
     if (!label) continue;
-    const rank = ancestorIds.indexOf(parentId);
-    contexts.push({ text: label, source: "dom", order: rank < 0 ? contexts.length : rank });
+    contexts.push({ text: label, source: "dom", order: ancestorRank.get(parentId) ?? 0 });
   }
 
   return contexts;
@@ -734,6 +789,7 @@ interface RenderState {
   children: Map<number | null, VomNode[]>;
   parentMap: Map<number, number | null>;
   nodesById: Map<number, VomNode>;
+  domContextIndex: DomContextIndex;
   duplicateRefNames: Set<string>;
   surfaceMap: Map<number, CondSurface>;
   scopeMap: Map<number, ActiveScopeBlock>;
@@ -768,20 +824,25 @@ function emitActiveScopeBlock(scope: ActiveScopeBlock, depth: number, state: Ren
   }
 }
 
-function renderTree(
-  children: Map<number | null, VomNode[]>,
-  parentId: number | null,
+function pushRenderChildren(
+  stack: Array<{ node: VomNode; depth: number }>,
+  children: readonly VomNode[],
   depth: number,
-  state: RenderState,
 ): void {
-  if (state.stopped) return;
+  for (let index = children.length - 1; index >= 0; index -= 1) {
+    stack.push({ node: children[index], depth });
+  }
+}
 
-  const nodes = children.get(parentId) ?? [];
-  for (const node of nodes) {
-    if (state.stopped) return;
+function renderTree(children: Map<number | null, VomNode[]>, state: RenderState): void {
+  const stack: Array<{ node: VomNode; depth: number }> = [];
+  pushRenderChildren(stack, children.get(null) ?? [], 1);
+
+  while (stack.length > 0 && !state.stopped) {
+    const { node, depth } = stack.pop() as { node: VomNode; depth: number };
 
     if (!shouldRender(node)) {
-      renderTree(children, node.id, depth, state);
+      pushRenderChildren(stack, children.get(node.id) ?? [], depth);
       continue;
     }
 
@@ -798,7 +859,7 @@ function renderTree(
     if (nextTokens > state.maxTokens) {
       state.truncated = true;
       state.stopped = true;
-      return;
+      break;
     }
 
     state.lines.push(line);
@@ -823,7 +884,7 @@ function renderTree(
     if ((ref && shouldSkipRedundantRefChildren(node)) || shouldSkipRedundantChildren(node, state)) {
       continue;
     }
-    renderTree(children, node.id, depth + 1, state);
+    pushRenderChildren(stack, children.get(node.id) ?? [], depth + 1);
   }
 }
 
@@ -848,12 +909,13 @@ function renderNodes(
     children,
     parentMap: buildParentMap(nodes),
     nodesById: new Map(nodes.map((node) => [node.id, node])),
+    domContextIndex: buildDomContextIndex(nodes),
     duplicateRefNames: duplicateReferenceNames(nodes),
     surfaceMap: new Map(surfaces.map((surface) => [surface.triggerId, surface])),
     scopeMap: new Map(activeScopeBlocks.map((scope) => [scope.triggerId, scope])),
   };
 
-  renderTree(children, null, 1, state);
+  renderTree(children, state);
 
   return state;
 }
@@ -922,23 +984,33 @@ function paintLineageByFrame(
   return lineage;
 }
 
+function cachedPaintLineageByFrame(
+  node: VomNode,
+  parentMap: Map<number, number | null>,
+  nodesById: Map<number, VomNode>,
+  cache: Map<number, Map<string | undefined, VomNode>>,
+): Map<string | undefined, VomNode> {
+  const cached = cache.get(node.id);
+  if (cached) return cached;
+  const lineage = paintLineageByFrame(node, parentMap, nodesById);
+  cache.set(node.id, lineage);
+  return lineage;
+}
+
 /** Resolve both nodes to the nearest document where their paint order is comparable. */
 function comparablePaintNodes(
   target: VomNode,
   blocker: VomNode,
   parentMap: Map<number, number | null>,
   nodesById: Map<number, VomNode>,
+  lineageCache: Map<number, Map<string | undefined, VomNode>>,
 ): { target: VomNode; blocker: VomNode } | null {
   if (target.frameId === blocker.frameId) return { target, blocker };
-  const targetLineage = paintLineageByFrame(target, parentMap, nodesById);
-  let blockerInFrame: VomNode | undefined = blocker;
-  let guard = 0;
-  while (blockerInFrame && guard <= parentMap.size) {
-    const targetInFrame = targetLineage.get(blockerInFrame.frameId);
+  const targetLineage = cachedPaintLineageByFrame(target, parentMap, nodesById, lineageCache);
+  const blockerLineage = cachedPaintLineageByFrame(blocker, parentMap, nodesById, lineageCache);
+  for (const [frameId, blockerInFrame] of blockerLineage) {
+    const targetInFrame = targetLineage.get(frameId);
     if (targetInFrame) return { target: targetInFrame, blocker: blockerInFrame };
-    const parentId: number | null = parentMap.get(blockerInFrame.id) ?? null;
-    blockerInFrame = parentId === null ? undefined : nodesById.get(parentId);
-    guard += 1;
   }
   return null;
 }
@@ -949,12 +1021,13 @@ function isBlockedByRegion(
   parentMap: Map<number, number | null>,
   nodesById: Map<number, VomNode>,
   viewportCoverage: number,
+  lineageCache: Map<number, Map<string | undefined, VomNode>>,
 ): boolean {
   if (target.id === blocker.id) return false;
   if (isAncestorOf(parentMap, blocker.id, target.id)) return false;
   if (isAncestorOf(parentMap, target.id, blocker.id)) return false;
   if (!target.rect || !blocker.rect) return false;
-  const paintNodes = comparablePaintNodes(target, blocker, parentMap, nodesById);
+  const paintNodes = comparablePaintNodes(target, blocker, parentMap, nodesById, lineageCache);
   if (!paintNodes) return false;
 
   const points = interactionPoints(target.rect);
@@ -979,17 +1052,22 @@ function isBlockedByRegion(
   return points.some(([x, y]) => rectContains(blocker.rect as Rect, x, y));
 }
 
-function collectDescendantsOfIds(nodes: VomNode[], roots: Set<number>): Set<number> {
+function collectDescendants(nodes: VomNode[], roots: Set<number>): Set<number> {
+  const children = new Map<number, number[]>();
+  for (const node of nodes) {
+    if (node.parentId === null) continue;
+    const siblings = children.get(node.parentId) ?? [];
+    siblings.push(node.id);
+    children.set(node.parentId, siblings);
+  }
+
   const included = new Set(roots);
-  let changed = true;
-  while (changed) {
-    changed = false;
-    for (const node of nodes) {
-      if (included.has(node.id)) continue;
-      if (node.parentId !== null && included.has(node.parentId)) {
-        included.add(node.id);
-        changed = true;
-      }
+  const queue = [...roots];
+  for (let index = 0; index < queue.length; index += 1) {
+    for (const childId of children.get(queue[index]) ?? []) {
+      if (included.has(childId)) continue;
+      included.add(childId);
+      queue.push(childId);
     }
   }
   return included;
@@ -998,6 +1076,7 @@ function collectDescendantsOfIds(nodes: VomNode[], roots: Set<number>): Set<numb
 function applyActiveRegionPolicy(nodes: VomNode[], scene: VomScene): VomNode[] {
   const parentMap = buildParentMap(nodes);
   const nodesById = new Map(nodes.map((node) => [node.id, node]));
+  const lineageCache = new Map<number, Map<string | undefined, VomNode>>();
   const candidates = nodes
     .filter(isPositionedRegionCandidate)
     .map((node) => {
@@ -1014,40 +1093,29 @@ function applyActiveRegionPolicy(nodes: VomNode[], scene: VomScene): VomNode[] {
   for (const target of nodes) {
     if (!isVomReferenceNode(target)) continue;
     const blocked = candidates.some((candidate) =>
-      isBlockedByRegion(target, candidate.node, parentMap, nodesById, candidate.viewportCoverage),
+      isBlockedByRegion(
+        target,
+        candidate.node,
+        parentMap,
+        nodesById,
+        candidate.viewportCoverage,
+        lineageCache,
+      ),
     );
     if (blocked) blockedRoots.add(target.id);
   }
 
   if (blockedRoots.size === 0) return nodes;
-  const blocked = collectDescendantsOfIds(nodes, blockedRoots);
+  const blocked = collectDescendants(nodes, blockedRoots);
   return nodes.filter((node) => !blocked.has(node.id));
 }
 
-function collectDescendantsOfMembers(nodes: VomNode[], members: Set<number>): Set<number> {
-  const included = new Set(members);
-  let changed = true;
-
-  while (changed) {
-    changed = false;
-    for (const node of nodes) {
-      if (included.has(node.id)) continue;
-      if (node.parentId !== null && included.has(node.parentId)) {
-        included.add(node.id);
-        changed = true;
-      }
-    }
-  }
-
-  return included;
-}
-
 function countRenderable(nodes: VomNode[]): number {
   return nodes.filter(shouldRender).length;
 }
 
 function renderDoubleLayer(scene: VomScene, layer: BlockingLayer, options: VomOptions): VomResult {
-  const included = collectDescendantsOfMembers(scene.nodes, layer.members);
+  const included = collectDescendants(scene.nodes, layer.members);
   const visibleNodes = scene.nodes.filter((node) => included.has(node.id));
   const hiddenCount = countRenderable(scene.nodes.filter((node) => !included.has(node.id)));
   const header = [