Merge pull request #1030 from rudycelekli/contrib/gods-009-route-cap-truthfulness-20261011-reviewed

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

CHANGELOG.md

@@ -24,6 +24,9 @@
   the five borough cores load and `CCTV_NYC_MAX_SOURCES` changes the cap. The catalog-wide ceiling is
   unchanged; extra cameras share it round-robin with the other packs.
 
+- Directions no longer shows a truncation notice for a route with exactly 200
+  turns, and a roundabout at the 200th turn keeps its exit distance.
+
 - Weather records keep missing conditions unknown and refuse summaries without a measured temperature.
 
 - Tool string length validation counts Unicode characters correctly, including characters outside the basic multilingual plane.

docs/CURRENT-STATE.md

@@ -3399,9 +3399,10 @@ rate limit from the routing service is reported as one instead of as "no route
 found". `src/data/routeSteps.js` turns OSRM maneuver type / modifier / exit /
 road name into one plain-English sentence per decision, folding
 `exit roundabout` steps into the roundabout they leave, and caps one route at
-200 maneuvers — a route past that cap is reported as cut off, in the row
-summary and as the last line of the list, because the arrival step is among
-the ones dropped.
+200 maneuvers — a route with more is reported as cut off, in the row summary
+and as the last line of the list, because the arrival step is among the ones
+dropped. A route of exactly 200 is complete, and a roundabout exit after the
+200th keeps folding into it.
 
 A step's card opens from its dot on the globe or from its line in the list, and
 the list covers every step including departure and arrival, which have no dot.

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 };

src/data/routeSteps.test.mjs

@@ -206,9 +206,9 @@ test('the step list is capped, and the cap is reported rather than hidden', () =
   // would present a route that simply stops in the middle of a road.
   assert.equal(cut.truncated, true);
   const exact = normalizeOsrmSteps({
-    legs: [{ steps: many.slice(0, ROUTE_STEPS_MAX - 1) }],
+    legs: [{ steps: many.slice(0, ROUTE_STEPS_MAX) }],
   });
-  assert.equal(exact.steps.length, ROUTE_STEPS_MAX - 1);
+  assert.equal(exact.steps.length, ROUTE_STEPS_MAX);
   assert.equal(exact.truncated, false, 'a route that fits is not cut');
 });