Comment/XML-doc changes only:
- add summaries to ~10k test methods, fixtures, fakes and helpers
(+ <param> on theories, <returns> on async Task methods,
<inheritdoc/> on interface implementations the checker can resolve)
- strip ~2.6k project-tracking references (WP*, P*-*, row-NN, Task N,
#NN, Component-0NN) from comments, keeping the explanatory text;
reword false positives in comments only
- real docs on fakes implementing BCL/library interfaces
(IDisposable, ILogger, IOptionsMonitor, IAsyncLifetime)
- reword the last 5 src/ false positives (CWE-1236, failures-1,
year-0001, M365)
Only non-comment edits: four one-line nested classes split across lines
so members can carry docs. Build 0 errors / 0 warnings.
AuditLog.Tests flaked under parallel full-solution runs. Three distinct
mechanisms, all load-sensitive and all green in isolation.
1. MsSqlMigrationFixture create+migrate saturation (the register's headline).
Database NAMING was already isolated (a guid per fixture), but nothing
bounded how many fixtures ran CREATE DATABASE + the ~100-migration chain at
once. xunit parallelises processor-count collections PER PROCESS, and a
solution-level `dotnet test` starts several MSSQL-backed processes together,
so the dev container saw dozens of simultaneous fresh-database migrations.
That is resource saturation, not object-level locking, and it pushed
individual DDL statements past EF's default 30s command timeout — every
failure had the identical fingerprint the register recorded:
MsSqlMigrationFixture..ctor -> Migrator.MigrateAsync -> SqlException
"Execution Timeout Expired" (error 258), which xunit surfaces as
"Class fixture type ... threw in its constructor" against every test in the
class.
Fix: a machine-wide counting semaphore over the create+migrate window, built
from sp_getapplock on master (ScadaBridgeTestMigrate/0..N-1, default 4 slots,
SCADABRIDGE_MSSQL_TEST_MIGRATE_SLOTS to override). An xunit collection cannot
do this — the contention is cross-PROCESS, so the arbiter has to live on the
shared server. The gate connection is unpooled (a pooled connection defers the
implicit release of a session-scoped app lock until reuse) and releases
explicitly; a crashed process drops its connection and SQL releases the lock,
so the gate cannot wedge the suite, and a deadline miss proceeds ungated
rather than failing. Migration commands also get a 300s timeout and
CREATE/DROP DATABASE 120s: under a bounded queue the server is busy but
progressing, so waiting is the correct response. Plus a once-per-process
best-effort sweep of ScadaBridgeAuditMigTest_* databases older than 2h so a
killed run does not leave strays, and the connectivity probe now retries
(3 attempts) — a busy server misread as an absent one would silently turn
every MSSQL test into a Skip, which reads green and is worse than a red.
2. PartitionPurgeTests leaked AuditLogPurgeActors. Each ticks every 100ms and
switches out the Jan-2026 partition; they were only stopped implicitly by
TestKit Dispose -> Shutdown, which is timeout-bounded and does not fail when
it expires. Under load a previous test's actor was still ticking against the
shared per-class fixture DB, so PerChannelOverride_... found its seeded
Jan-15-2026 row already gone (Expected: 1, Actual: 0).
3. NotifyDispatcherAuditTrailTests leaked NotificationOutboxActors, same shape.
The dispatcher claims EVERY due row, not just the test's siteId, so a leaked
actor delivered the next test's notification through its own exhausted
QueuedOutcomeAdapter — a transient outcome, leaving the row in Retrying
(Expected: Delivered, Actual: Retrying) and audit counts short.
Both fixed by stopping the actor inside the test that created it
(Watch/Stop/ExpectTerminated), removing the dependency on shutdown timing.
Evidence. Reproducer: 10 concurrent ConfigurationDatabase.Tests processes
against the one dev SQL Server — before, 10/10 processes failed (17-77 failures
each, 100% the ctor->MigrateAsync timeout); after, 3 consecutive runs 10/10
green, 395/395 each. Realistic shape (3x AuditLog.Tests + 1x
ConfigurationDatabase.Tests concurrent): first post-fix run still showed the
NotifyDispatcher leak, then 3 consecutive clean runs. Standalone: AuditLog.Tests
383/383, ConfigurationDatabase.Tests 395/395 (12s, unchanged from baseline),
SiteCallAudit.Tests 66/66. No orphan databases or stuck app locks left behind.
docs/test_infra/test_infra_db.md documents the ephemeral per-test-class
databases, the throttle and its env override, the timeouts, and the stray sweep.
Both NotifyDispatcher_AuditWriter_Throws_DeliveryStillSucceeds and
NotificationDispatch_BrokenAuditWriter_StillTransitionsToDelivered read the
throwing writer's attempt counter with a bare Assert immediately after an
AwaitAssert on the Notifications row reaching Delivered. That assumes the audit
writes happen no later than the operational status write, which the dispatcher
deliberately does NOT guarantee: DeliverOneAsync persists the delivery state
first (NotificationOutboxActor.cs:657) and only then emits the Attempted
(:663) and terminal (:676) audit rows — audit is best-effort and must never
gate the user-facing action. Observing Delivered therefore establishes no
happens-before edge with the writer, and under a loaded full-solution parallel
run the continuation after the DB write can be scheduled after the poll that
saw Delivered, so the counter reads 0 and the test fails with "saw 0".
Reproduced deterministically by delaying only the post-update audit emission,
which yields both observed failure messages verbatim; with the fix in place the
same injected delay passes, and suppressing the emissions entirely still fails
both tests with the identical messages — the claims (delivery despite audit
failure, and attempts >= N) are unchanged in force, only the ordering
assumption is gone.
Test-only change; the update-then-audit ordering predates the remediation
(#23 M4) and is correct as written.
Joseph Doherty