From 6360b2514e9895a31e4d607f1e53d15cdfea815f Mon Sep 17 00:00:00 2001
From: Diego Rodrigues de Sa e Souza <diegosouza.pw@gmail.com>
Date: Sun, 19 Jul 2026 13:04:35 -0300
Subject: [PATCH] test(router-eval): assert regression reasons instead of
 counting entries
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The test named 'captures AIQ and cost regressions' only asserted
regressions.length > 0, which re-implements a condition the production
comparison owns and passes even if either regression stops being
reported. Assert the actual AIQ and cost reasons instead — strictly
stronger and clears the weakened-assert gate.
---
 .../maintenance/router-eval-test-assert-strengthen.md    | 1 +
 tests/unit/router-eval.test.ts                           | 9 ++++++++-
 2 files changed, 9 insertions(+), 1 deletion(-)
 create mode 100644 changelog.d/maintenance/router-eval-test-assert-strengthen.md

diff --git a/changelog.d/maintenance/router-eval-test-assert-strengthen.md b/changelog.d/maintenance/router-eval-test-assert-strengthen.md
new file mode 100644
index 0000000000..c6f6e86046
--- /dev/null
+++ b/changelog.d/maintenance/router-eval-test-assert-strengthen.md
@@ -0,0 +1 @@
+- Strengthen the `compareRouterEvalRuns` regression test to assert the actual AIQ and cost regression reasons instead of counting entries, clearing the weakened-assert (test-masking) gate on the release tip.
diff --git a/tests/unit/router-eval.test.ts b/tests/unit/router-eval.test.ts
index ba520a6c86..4d6527704f 100644
--- a/tests/unit/router-eval.test.ts
+++ b/tests/unit/router-eval.test.ts
@@ -73,7 +73,14 @@ test("compareRouterEvalRuns captures AIQ and cost regressions", () => {
     relativeCostIncrease: 1.2,
   });
 
-  assert.equal(comparison.regressions.length > 0, true);
+  assert.ok(
+    comparison.regressions.some((reason) => reason.startsWith("AIQ dropped by")),
+    "expected an AIQ regression to be reported"
+  );
+  assert.ok(
+    comparison.regressions.some((reason) => reason.startsWith("cost increased by")),
+    "expected a cost regression to be reported"
+  );
   assert.equal(comparison.delta.aiq <= 0, true);
   assert.equal(comparison.delta.costUsd > 0, true);
 });