fix(directions): report truncation only when a maneuver was actually omitted

src/data/route-cap-truthfulness.test.mjs

@@ -0,0 +1,24 @@
+import test from 'node:test';
+import assert from 'node:assert/strict';
+import { normalizeOsrmSteps, ROUTE_STEPS_MAX } from './routeSteps.js';
+const step = (type) => ({
+  maneuver: { type, location: [10, 20] },
+  distance: 10,
+  duration: 1,
+});
+test('exact-cap routes remain complete and boundary exits retain their distance', () => {
+  const steps = Array.from({ length: ROUTE_STEPS_MAX }, () => step('turn'));
+  assert.equal(normalizeOsrmSteps({ legs: [{ steps }] }).truncated, false);
+  assert.equal(
+    normalizeOsrmSteps({ legs: [{ steps: [...steps, step('turn')] }] })
+      .truncated,
+    true,
+  );
+  steps[steps.length - 1] = step('roundabout');
+  const result = normalizeOsrmSteps({
+    legs: [{ steps: [...steps, step('exit roundabout')] }],
+  });
+  assert.equal(result.truncated, false);
+  assert.equal(result.steps.length, ROUTE_STEPS_MAX);
+  assert.equal(result.steps.at(-1).distanceM, 20);
+});

src/data/routeSteps.js

@@ -185,9 +185,9 @@ export function normalizeOsrmSteps(route) {
         }
         continue;
       }
+      if (out.length >= ROUTE_STEPS_MAX) return { steps: out, truncated: true };
       step.instruction = instructionFor(step);
       out.push(step);
-      if (out.length >= ROUTE_STEPS_MAX) return { steps: out, truncated: true };
     }
   }
   return { steps: out, truncated: false };