Your Undo Stack Already Knows When to Revalidate. Stop Wiring It Per Feature.

TLDR

Sprinkling analysis revalidation calls (refreshAnalysis()) inside every individual canvas editing feature (place, drag, rotate, delete, group, paste) is a maintenance trap. Every feature addition introduces another place to forget invalidation, producing stale analysis reports. Because every meaningful document mutation already pushes a snapshot onto the undo history stack, hooking revalidation directly into pushHistory() guarantees 100% analysis coverage for all present and future editing tools.

Invalidation Pattern	Integration Points	Coverage for New Features	Stale Analysis Risk
Per-Feature Invalidation	Scattered across 20+ feature handlers	High risk (Easy to forget calls)	High (Fails on paste/rotate/group)
Undo Stack Funnel Hook	Single integration point (pushHistory)	100% Automatic Coverage	Zero (Guaranteed parity)

---

Problem statement: the whack-a-mole invalidation trap

In interactive canvas applications, running live background analysis (such as netlist linting, connectivity checks, or Design Rule Checking) requires re-evaluating document state after edits.

Developers typically call refreshAnalysis() manually inside each feature handler:

// NAIVE: Manual per-feature invalidation calls function onSymbolPlaced(symbol) {   placeSymbol(symbol);   refreshAnalysis(); // Easy to add here... }

function onElementsPasted(elements) {   pasteElements(elements);   // FORGOTTEN: Forgot to call refreshAnalysis()! Analysis is now STALE! }

As new features (paste, rotate, align, bulk import) are added over time, developers inevitably forget to include the invalidation call, producing stale reports that lose user trust.

---

Technical failure mode: silent invalidation gaps

1. Tooling Coupling: Feature tools (like wire drawing) must be explicitly aware of every background analyzer in the system.
2. Asymmetric State: Dragging a component updates the analysis, but rotating or pasting a component leaves stale analysis results visible on screen.

---

The fix & architecture: hooking the history stack funnel

Every undoable web editor already possesses a centralized funnel: the undo history stack. Every document mutation must call pushHistory() to be undoable.

Hook revalidation directly into pushHistory(), using a debounced scheduler to prevent UI stutter during active drag gestures:

// REFACTORED: Single-point revalidation via history stack hook
class HistoryManager {
  pushHistory(label, snapshot) {
    this.undoStack.push({ label, snapshot });
    this.redoStack = [];
// Trigger debounced analysis pass for ALL mutations!     this.scheduleAnalysisRevalidation();   }
scheduleAnalysisRevalidation() {     clearTimeout(this._debounceTimer);     this._debounceTimer = setTimeout(() => {       // Defer analysis execution if the user is in the middle of a drag gesture       if (this.isGestureActive) {         this.scheduleAnalysisRevalidation();         return;       }
runGlobalAnalysisPass();     }, 300);   } }

With this single hook:

• Placing, dragging, rotating, pasting, grouping, and deleting automatically trigger analysis updates.
• Future features written next year inherit live revalidation automatically on the day they call pushHistory().

Rule of thumb: Hook document revalidation and background analysis directly into your undo history stack's pushHistory() method rather than scattering refresh calls across individual editing tools.