From 76329557c4a547b1797794bab0cd00a91e590510 Mon Sep 17 00:00:00 2001
From: wellkilo <wellkilo@foxmail.com>
Date: Sun, 13 Sep 2026 05:14:26 +0800
Subject: [PATCH] test(metrics): derive oversized fixture from scan cap

Export the internal scan budget for regression tests and size the oversized-line fixture as exactly two bounded passes.
---
 scripts/lib/session-cost-snapshot.js    | 1 +
 tests/lib/session-cost-snapshot.test.js | 3 ++-
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/scripts/lib/session-cost-snapshot.js b/scripts/lib/session-cost-snapshot.js
index f95ddc8cb..779f83328 100644
--- a/scripts/lib/session-cost-snapshot.js
+++ b/scripts/lib/session-cost-snapshot.js
@@ -500,6 +500,7 @@ module.exports = {
   COST_SNAPSHOT_SCHEMA_VERSION,
   COST_SNAPSHOT_DIRECTORY,
   COST_LOG_FILENAME,
+  MAX_SCAN_BYTES,
   getCostSnapshotPath,
   isValidCostRow,
   chooseNewerCumulativeRow,
diff --git a/tests/lib/session-cost-snapshot.test.js b/tests/lib/session-cost-snapshot.test.js
index 5e004b49a..f941f8920 100644
--- a/tests/lib/session-cost-snapshot.test.js
+++ b/tests/lib/session-cost-snapshot.test.js
@@ -8,6 +8,7 @@ const path = require('path');
 const {
   appendSessionCostRow,
   getCostSnapshotPath,
+  MAX_SCAN_BYTES,
   maybePruneSessionCostSnapshots,
   readSessionCostSnapshot,
   refreshSessionCostSnapshot,
@@ -199,7 +200,7 @@ try {
   if (test('bounds oversized unterminated rows and caches the discarded prefix', () => {
     const caseRoot = path.join(root, 'oversized-line');
     fs.mkdirSync(caseRoot, { recursive: true });
-    const oversizedBytes = 32 * 1024 * 1024;
+    const oversizedBytes = 2 * MAX_SCAN_BYTES;
     fs.writeFileSync(
       path.join(caseRoot, 'costs.jsonl'),
       Buffer.alloc(oversizedBytes, 0x78)