ab_server integration fixture — per-family profiles + documented CI-fetch contract. Closes task #180 (AB CIP follow-up — ab_server CI fixture). Replaces the prior hardcoded single-family fixture with a parametric AbServerProfile abstraction covering ControlLogix / CompactLogix / Micro800 / GuardLogix. Prebuilt-Windows-binary fetch is documented as a CI YAML step rather than fabricated C#-side, because SHA-pinned binary distribution is a CI workflow concern (libplctag owns releases, we pin a version + verify hash) not a test-framework concern. New AbServerProfile record + KnownProfiles static class at tests/.../AbServerProfile.cs. Four profiles: ControlLogix (widest coverage — DINT/REAL/BOOL/SINT/STRING atomic + DINT[16] array so the driver's @tags Symbol-Object decoder + array-bound path both get end-to-end coverage), CompactLogix (atomic subset — driver-side ConnectionSize quirk from PR 10 still applies since ab_server doesn't enforce the narrower limit), Micro800 (ab_server has no dedicated --plc micro800 mode — falls back to controllogix while driver-side path enforces empty routing + unconnected-only per PR 11; real Micro800 coverage requires a 2080 lab rig), GuardLogix (ab_server has no safety subsystem — profile emulates the _S-suffixed naming contract the driver's safety-ViewOnly classification reads in PR 12; real safety-lock behavior requires a 1756-L8xS physical rig). Each profile composes --plc + --tag args via BuildCliArgs(port) — pure string formatter so the composition logic is unit-testable without launching the simulator. AbServerFixture gains a ctor overload taking AbServerProfile + port (defaults back to ControlLogix on parameterless ctor so existing test suites keep compiling). Fixture's InitializeAsync hands the profile's CLI args to ProcessStartInfo.Arguments. New AbServerTheoryAttribute mirrors AbServerFactAttribute but extends TheoryAttribute so a single test can MemberData over KnownProfiles.All + cover all four families. AbCipReadSmokeTests converted from single-fact to theory parametrized over KnownProfiles.All — one row per family reads TestDINT + asserts Good status + Healthy driver state. Fixture lifecycle is explicit try/finally rather than await using because IAsyncLifetime.DisposeAsync returns ValueTask + xUnit's concrete IAsyncDisposable shim depends on xunit version; explicit beats implicit here. Eight new unit tests in AbServerProfileTests.cs (runs without the simulator so CI green even when the binary is absent): BuildCliArgs composes port + plc + tag flags in the documented order; empty seed-tag list still emits port + plc; SeedTag.ToCliSpec handles both 2-segment scalar + 3-segment array; KnownProfiles.ForFamily returns expected --plc arg for every family (verifies Micro800 + GuardLogix both fall back to controllogix); KnownProfiles.All covers every AbCipPlcFamily enum value (regression guard — adding a new family without a profile fails this test); ControlLogix seeds every atomic type the driver supports; GuardLogix seeds at least one _S-suffixed safety tag. Integration tests still skip cleanly when ab_server isn't on PATH. 11/11 unit tests passing in this project (8 new + 3 prior). Full Admin solution builds 0 errors. docs/v2/test-data-sources.md gets a new "CI fixture" subsection under §2.Gotchas with the exact GitHub Actions YAML step — fetch the pinned libplctag release, SHA256-verify against a pinned hash recorded in the repo's CI lockfile (drift = fail closed), extract, append to PATH. The C# harness stays PATH-driven so dev-box installs (cmake + make from source) work identically to CI.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

docs/v2/test-data-sources.md

@@ -189,6 +189,35 @@ Modbus has no native String, DateTime, or Int64 — those rows are skipped on th
 - **ab_server tag-type coverage is finite** (BOOL, DINT, REAL, arrays, basic strings). UDTs and `Program:` scoping are not fully implemented. Document an "ab_server-supported tag set" in the harness and exclude the rest from default CI; UDT coverage moves to the Studio 5000 Emulate golden-box tier.
 - CIP has no native subscriptions, so polling behavior matches real hardware.
 
+### CI fixture (task #180)
+
+The integration harness at `tests/ZB.MOM.WW.OtOpcUa.Driver.AbCip.IntegrationTests/` exposes two test-time contracts:
+
+- **`AbServerFixture(AbServerProfile)`** — starts the simulator with the CLI args composed from the profile's `--plc` family + seed-tag set. One fixture instance per family, one simulator process per test case (smoke tier). For larger suites that can share a simulator across several reads/writes, use a `IClassFixture<AbServerFixture>` wrapper per family.
+- **`KnownProfiles.{ControlLogix, CompactLogix, Micro800, GuardLogix}`** — the four per-family profiles. Drives the simulator's `--plc` mode + the preseed `--tag name:type[:size]` set. Micro800 + GuardLogix fall back to `controllogix` under the hood because ab_server has no dedicated mode for them — the driver-side family profile still enforces the narrower connection shape / safety classification separately.
+
+**CI step (intended — fleet-ops to wire):**
+
+```yaml
+# GitHub Actions step placed before `dotnet test`:
+- name: Fetch ab_server
+  shell: pwsh
+  run: |
+    $ver = '<pinned libplctag release tag>'
+    $url = "https://github.com/libplctag/libplctag/releases/download/$ver/ab_server-windows-x64.zip"
+    Invoke-WebRequest $url -OutFile $env:RUNNER_TEMP/ab_server.zip
+    # SHA256 check against a pinned value recorded in this repo's CI lockfile — drift = fail closed
+    $expected = '<pinned sha256>'
+    $actual = (Get-FileHash -Algorithm SHA256 $env:RUNNER_TEMP/ab_server.zip).Hash
+    if ($expected -ne $actual) { throw "ab_server hash mismatch" }
+    Expand-Archive $env:RUNNER_TEMP/ab_server.zip -DestinationPath $env:RUNNER_TEMP/ab_server
+    echo "$env:RUNNER_TEMP/ab_server" >> $env:GITHUB_PATH
+```
+
+The fixture's `LocateBinary()` picks the binary up off PATH so the C# harness doesn't own the download — CI YAML is the right place for version pinning + hash verification. Developer workstations install the binary once from source (`cmake + make ab_server` under a libplctag clone) and the same fixture works identically.
+
+Tests without ab_server on PATH are marked `Skip` via `AbServerFactAttribute` / `AbServerTheoryAttribute`, so fresh-clone runs without the simulator still pass all unit suites in this project.
+
 ---
 
 ## 3. Allen-Bradley Legacy (SLC 500 / MicroLogix, PCCC)