Stabilize parallel snapshot refresh test

TESTING_GUIDE.md

@@ -696,7 +696,7 @@ Use `docs/test-doc-maintenance-plan.md` before moving oversized suites or adding
 - `QueryCommandRunnerBatchIssue4723Tests.cs`
   CLI batch coverage for structured command objects, configurable input/output budgets, bounded parallel read overlap, input-order result emission, per-item failure isolation, and cancellation/console restoration. The deterministic overlap test blocks the first worker until the second finishes through batch-only test seams; keep those seams reset in `finally` and do not replace the signal with timing assertions.
 - `QueryCommandRunnerBatchIssue4872Tests.cs`
-  Parallel batch session-reuse coverage. Keep the exact worker-slot session bound, serial/parallel result and input-order parity, between-item checkpointed-WAL snapshot and direct-session refresh, validation/reader-construction failure cleanup, hot-WAL snapshot fixture, warmup, and the generous 12-item/3-item ratio guard together. The benchmark injects deterministic database-open/schema work through a test seam; its fixed delay models phase cost only, while worker coordination remains signal-driven.
+  Parallel batch session-reuse coverage. Keep the exact worker-slot session bound, serial/parallel result and input-order parity, between-item checkpointed-WAL snapshot and direct-session refresh, validation/reader-construction failure cleanup, hot-WAL snapshot fixture, warmup, and the generous 12-item/3-item ratio guard together. The checkpointed-WAL snapshot refresh gives each status wave two minutes of headroom for the loaded net9 full suite; keep its completion signals and result/session assertions intact rather than weakening the concurrency contract. The benchmark injects deterministic database-open/schema work through a test seam; its fixed delay models phase cost only, while worker coordination remains signal-driven.
 - `PropertyBasedParserTests.cs`
   FsCheck-driven property tests for parser-heavy paths called out in issue #1572: `ArgHelper.WantsHelp` and `ProgramRunner.IsProjectPathArg` never throw on arbitrary inputs; `FileIndexer.NormalizePathSeparators` is idempotent under double application; the literal-safe FTS5 sanitizer (`DbReader.SanitizeFtsQuery`) always emits a query that a real in-memory FTS5 virtual table can parse. They complement, not replace, the example-based tests in `ArgHelperTests.cs` / `QueryCommandRunnerTests.cs`.
 - `TestProjectHelper.cs`, `TestDeterminism.cs`, `RepositoryTestPaths.cs`, `TestConsoleLock.cs`
@@ -1648,7 +1648,7 @@ dotnet test --filter "FullyQualifiedName~GitHelperTests"
 - `QueryCommandRunnerBatchIssue4723Tests.cs`
   structured command object、設定可能な input / output budget、上限付き parallel read の重複実行、入力順の result 出力、item ごとの failure isolation、cancellation / console 復元を対象とする CLI batch test です。決定的な overlap test は batch 専用 test seam を通じて第 1 worker を第 2 worker の完了まで block します。seam は `finally` で必ず reset し、signal を timing assertion に置き換えないでください。
 - `QueryCommandRunnerBatchIssue4872Tests.cs`
-  parallel batch の session 再利用を検証します。worker slot 数と一致する厳密な session 上限、serial / parallel の result と入力順 parity、item 間の checkpoint 済み WAL snapshot / direct session 更新、validation / reader 構築失敗時の cleanup、hot-WAL snapshot fixture、warmup、十分に余裕を持たせた 12-item / 3-item ratio guard を一緒に維持してください。benchmark は test seam から決定的な database-open / schema 作業を注入します。固定 delay は phase cost のモデル化だけに使い、worker coordination は引き続き signal で制御します。
+  parallel batch の session 再利用を検証します。worker slot 数と一致する厳密な session 上限、serial / parallel の result と入力順 parity、item 間の checkpoint 済み WAL snapshot / direct session 更新、validation / reader 構築失敗時の cleanup、hot-WAL snapshot fixture、warmup、十分に余裕を持たせた 12-item / 3-item ratio guard を一緒に維持してください。checkpoint 済み WAL snapshot の refresh test は、負荷がかかる net9 full suite に備えて各 status wave に 2 分の余裕を持たせます。completion signal と result / session assertion は concurrency 契約を弱めず維持してください。benchmark は test seam から決定的な database-open / schema 作業を注入します。固定 delay は phase cost のモデル化だけに使い、worker coordination は引き続き signal で制御します。
 - `PropertyBasedParserTests.cs`
   issue #1572 で挙げられたパーサー系経路に対する FsCheck 駆動の property テスト: `ArgHelper.WantsHelp` と `ProgramRunner.IsProjectPathArg` が任意入力で例外を投げないこと、`FileIndexer.NormalizePathSeparators` が二重適用で idempotent であること、literal-safe な FTS5 サニタイザ (`DbReader.SanitizeFtsQuery`) が常にインメモリ FTS5 仮想テーブルで parse 可能なクエリを出力すること。`ArgHelperTests.cs` / `QueryCommandRunnerTests.cs` の例ベーステストを置き換えるものではなく補完します。
 - `TestProjectHelper.cs`、`TestDeterminism.cs`、`RepositoryTestPaths.cs`、`TestConsoleLock.cs`

changelog.d/unreleased/5015.fixed.md

@@ -0,0 +1,16 @@
+---
+category: fixed
+issues:
+  - 5015
+affected:
+  - tests/CodeIndex.Tests/QueryCommandRunnerBatchIssue4872Tests.cs
+  - TESTING_GUIDE.md
+---
+
+## English
+
+- **Parallel batch snapshot refresh coverage now has deterministic net9 full-suite headroom (#5015)** — each signal-gated status wave can run for up to two minutes, while the existing concurrency, refreshed-result, and session-count assertions remain unchanged.
+
+## 日本語
+
+- **parallel batch の snapshot refresh coverage に net9 full suite 向けの決定的な余裕を追加しました (#5015)** — signal で制御する各 status wave を最大 2 分まで実行できるようにしつつ、既存の concurrency、更新後 result、session 数の assertion は維持しています。

tests/CodeIndex.Tests/QueryCommandRunnerBatchIssue4872Tests.cs

@@ -121,6 +121,7 @@ INSERT INTO files(path, lang, size, lines, checksum, modified)
         using var stderr = new StringWriter();
         using var firstWaveCompleted = new CountdownEvent(2);
         using var cancellation = new CancellationTokenSource();
+        var statusWaveTimeout = TimeSpan.FromMinutes(2);
         Task<int>? runTask = null;
         var openedSessions = 0;
         QueryCommandRunner.BatchParallelSessionOpenedForTesting =
@@ -144,7 +145,7 @@ INSERT INTO files(path, lang, size, lines, checksum, modified)
             input.WriteLine("""{"command":"status","args":["--json"]}""");
             input.WriteLine("""{"command":"status","args":["--json"]}""");
             Assert.True(
-                firstWaveCompleted.Wait(TimeSpan.FromSeconds(60)),
+                firstWaveCompleted.Wait(statusWaveTimeout),
                 "The first parallel batch wave did not complete.");
 
             using (var update = writer.CreateCommand())
@@ -163,7 +164,7 @@ INSERT INTO files(path, lang, size, lines, checksum, modified)
             input.WriteLine("""{"command":"status","args":["--json"]}""");
             input.Complete();
 
-            var exitCode = await runTask.WaitAsync(TimeSpan.FromSeconds(60));
+            var exitCode = await runTask.WaitAsync(statusWaveTimeout);
             Assert.Equal(CommandExitCodes.Success, exitCode);
             Assert.Equal(string.Empty, stderr.ToString());