Error Fix: Two Silent Bugs in the Path Reconciler Refactor

TLDR

Refactoring PDF vector parsing modules introduced two distinct silent defects: a missed export rename (extractSubpaths replacing extractPaths) in downstream consumers that caused load-time SyntaxError crashes, and an unbraced switch case block containing const declarations that triggered lexical scope shadowing conflicts. Adding block braces {} to switch cases isolates variable scope, while global codebase searches resolve export renaming drift.

Defect Area	Root Cause	Engineering Solution
Import Export Drift	Renamed module export left stale imports	Update pdfAnalyzer.js import + invoke reconcile()
Switch Scope Conflict	const inside unbraced case clause	Enclose case bodies in explicit block braces {}

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Technical defect diagnostics & remediation

1. Downstream module import synchronisation

Renaming extractPaths to extractSubpaths inside ctmAdapter.js caused pdfAnalyzer.js to fail at import time:

// REFACTORED: Import extractSubpaths and reconcile pipeline explicitly
import { extractSubpaths } from './ctmAdapter.js';
import { reconcile } from './pathReconciler.js';
export function analyzePdfVectorGeometry(opList, viewport, OPS) {   const { subpaths, filledRects: rawFilledRects } = extractSubpaths(opList, viewport, OPS);   const { segments } = reconcile(subpaths, rawFilledRects, viewport);   return { segmentsCount: segments.length }; }

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2. Lexical scope isolation in switch cases

Declaring const variables inside unbraced case clauses pollutes the entire switch statement's lexical block:

// REFACTORED: Enclose switch case body in explicit block braces
switch (op) {
  case OPS.closePath: {
    bufferSeg(rawPendingX, rawPendingY, subpathStartX, subpathStartY);
    rawPendingX = subpathStartX; 
    rawPendingY = subpathStartY;
    const [cpx, cpy] = toViewport(subpathStartX, subpathStartY);
    pendingX = cpx; 
    pendingY = cpy;
    currentSubpath.closed = true;
    break;
  }
}

Rule of thumb: Always wrap switch case clauses in explicit block braces {} when declaring const or let variables.