fix(status-codes): correct BadDeviceFailure from 0x80550000 to 0x808B0000

Driver.Cli.Common-007 + Driver.Cli.Common-008 resolution.

Driver.Cli.Common-007 (High, Correctness):
  0x80550000 is the canonical OPC UA spec value for BadSecurityPolicyRejected,
  not BadDeviceFailure. The correct spec value for BadDeviceFailure is
  0x808B0000 (verified against OPC Foundation Opc.Ua.StatusCodes;
  corroborated locally by Driver.Galaxy.Runtime.StatusCodeMap and both
  Wonderware historian quality mappers which all hand-pin the correct
  value).

  The bug was duplicated across six driver modules:
    - FocasStatusMapper.BadDeviceFailure
    - AbCipStatusMapper.BadDeviceFailure
    - AbLegacyStatusMapper.BadDeviceFailure
    - TwinCATStatusMapper.BadDeviceFailure
    - ModbusDriver.StatusBadDeviceFailure
    - S7Driver.StatusBadDeviceFailure
  Plus the SnapshotFormatter shortlist that named 0x80550000 as
  BadDeviceFailure, and three downstream Modbus tests that asserted
  against the wrong value (so CI was blind).

  This commit fixes all six native-mapper constants, the formatter
  shortlist, and the three Modbus tests in one pass. Added a regression
  guard to FormatStatus_does_not_apply_pre_fix_wrong_names that pins
  0x80550000 never renders as BadDeviceFailure (mirroring the existing
  -001 wrong-name guards).

  Behavior change: OPC UA clients consuming the native drivers now see
  the canonical BadDeviceFailure (0x808B0000) on device-fault paths
  instead of the misnamed BadSecurityPolicyRejected (0x80550000). Wire-
  level status semantics now match operator-facing CLI labels.

Driver.Cli.Common-008 (Low, Testing):
  Deleted the redundant FormatStatus_names_native_driver_emitted_codes
  Theory — its five InlineData rows were already covered by the
  well-known Theory in the same commit (5a9c459), and used a weaker
  ShouldContain vs the well-known Theory's ShouldBe (exact match).

Verification:
  - Driver.Cli.Common.Tests: 43/43 pass (was 48 after the -008 deletion).
  - Driver.Modbus.Tests: 263/263 pass.
  - Driver.AbCip.Tests: 262/262.
  - Driver.AbLegacy.Tests: 157/157.
  - Driver.FOCAS.Tests: 178/178.
  - Driver.S7.Tests: 112/112.
  - Driver.TwinCAT.Tests: 131/131.
  Total: 1146 tests across the affected modules, all green.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
This commit is contained in:
Joseph Doherty
2026-05-23 17:14:28 -04:00
parent 41e62b2663
commit a6ae4e22d1
12 changed files with 55 additions and 35 deletions

View File

@@ -7,7 +7,7 @@
| Review date | 2026-05-23 |
| Commit reviewed | `a9be809` |
| Status | Reviewed |
| Open findings | 2 |
| Open findings | 0 |
## Checklist coverage
@@ -251,7 +251,7 @@ added to the `DriverCommandBase` class-summary driver enumeration in commit `7ff
| Severity | High |
| Category | Correctness & logic bugs |
| Location | `src/Drivers/Cli/ZB.MOM.WW.OtOpcUa.Driver.Cli.Common/SnapshotFormatter.cs:129` |
| Status | Open |
| Status | Resolved |
**Description:** Commit `5a9c459` added `0x80550000u => "BadDeviceFailure"` to the
`FormatStatus` shortlist, but `0x80550000` is the canonical OPC UA spec value for
@@ -302,6 +302,30 @@ original recommendation again: add a CI test that cross-checks every shortlist
entry against `Opc.Ua.StatusCodes` reflection so this class of bug stops
recurring.
**Resolution:** Resolved 2026-05-23 — corrected `SnapshotFormatter.FormatStatus`
to map `0x808B0000u => "BadDeviceFailure"` (was `0x80550000u`). Updated the
`InlineData` row in the well-known Theory accordingly; the redundant native-
emitted Theory was deleted entirely per Driver.Cli.Common-008. Added a regression
row to `FormatStatus_does_not_apply_pre_fix_wrong_names` pinning that
`0x80550000` no longer renders as `BadDeviceFailure` (mirroring the
Driver.Cli.Common-001 wrong-name guards). The underlying constant was also
corrected in all six native-protocol mappers as part of the same commit:
`FocasStatusMapper.BadDeviceFailure`, `AbCipStatusMapper.BadDeviceFailure`,
`AbLegacyStatusMapper.BadDeviceFailure`, `TwinCATStatusMapper.BadDeviceFailure`,
`ModbusDriver.StatusBadDeviceFailure`, `S7Driver.StatusBadDeviceFailure` — all
moved from `0x80550000u` to `0x808B0000u`. The three downstream Modbus tests
(`ModbusExceptionMapperTests` 3 InlineData rows + 1 ShouldBe assertion;
`ExceptionInjectionTests.StatusBadDeviceFailure` constant) updated to expect
the corrected code. **Behavior change:** OPC UA clients consuming the native
drivers now see the canonical `BadDeviceFailure` (0x808B0000) instead of the
misnamed `BadSecurityPolicyRejected` (0x80550000) on device-fault paths —
operator-facing CLI output and machine-readable status semantics now agree.
Suite totals after fix: Driver.Cli.Common.Tests 43 green (was 48 — minus 5
redundant rows); Modbus.Tests 263; AbCip.Tests 262; AbLegacy.Tests 157;
FOCAS.Tests 178; S7.Tests 112; TwinCAT.Tests 131; all green. The Opc.Ua.StatusCodes
cross-check the recommendation suggested is recorded as a follow-up worth
considering but is out of scope for this fix.
### Driver.Cli.Common-008
| Field | Value |
@@ -309,7 +333,7 @@ recurring.
| Severity | Low |
| Category | Testing coverage |
| Location | `tests/Drivers/Cli/ZB.MOM.WW.OtOpcUa.Driver.Cli.Common.Tests/SnapshotFormatterTests.cs:50-64` |
| Status | Open |
| Status | Resolved |
**Description:** Commit `5a9c459` adds a new
`FormatStatus_names_native_driver_emitted_codes` `[Theory]` whose five
@@ -332,3 +356,9 @@ it but switch to `ShouldBe($"0x{status:X8} ({expectedName})")` so its
assertion strength matches the rest of the file. Option (a) is cleaner: the
commit's "operator workflow" intent is documented well enough in the
well-known Theory comment block; the redundant Theory is dead weight.
**Resolution:** Resolved 2026-05-23 — took option (a): deleted the
`FormatStatus_names_native_driver_emitted_codes` Theory entirely. Its five
`InlineData` rows are covered by the well-known Theory's `ShouldBe` (strict
exact-match assertion), which is the authoritative shortlist test. Landed
alongside the Driver.Cli.Common-007 fix in the same commit.

View File

@@ -26,7 +26,7 @@ Each module's `findings.md` is the source of truth; this file is generated from
| [Driver.AbCip.Cli](Driver.AbCip.Cli/findings.md) | Claude Code | 2026-05-22 | `76d35d1` | Reviewed | 0 | 8 |
| [Driver.AbLegacy](Driver.AbLegacy/findings.md) | Claude Code | 2026-05-22 | `76d35d1` | Reviewed | 0 | 13 |
| [Driver.AbLegacy.Cli](Driver.AbLegacy.Cli/findings.md) | Claude Code | 2026-05-22 | `76d35d1` | Reviewed | 0 | 7 |
| [Driver.Cli.Common](Driver.Cli.Common/findings.md) | Claude Code | 2026-05-23 | `a9be809` | Reviewed | 2 | 8 |
| [Driver.Cli.Common](Driver.Cli.Common/findings.md) | Claude Code | 2026-05-23 | `a9be809` | Reviewed | 0 | 8 |
| [Driver.FOCAS](Driver.FOCAS/findings.md) | Claude Code | 2026-05-22 | `76d35d1` | Reviewed | 0 | 12 |
| [Driver.FOCAS.Cli](Driver.FOCAS.Cli/findings.md) | Claude Code | 2026-05-22 | `76d35d1` | Reviewed | 0 | 5 |
| [Driver.Galaxy](Driver.Galaxy/findings.md) | Claude Code | 2026-05-23 | `a9be809` | Reviewed | 4 | 18 |
@@ -49,7 +49,6 @@ Findings with status `Open` or `In Progress`, ordered by severity.
| ID | Severity | Category | Location | Description |
|---|---|---|---|---|
| Core.Scripting-012 | High | Security | `ForbiddenTypeAnalyzer.cs:60-76`, `ScriptSandbox.cs:96-126` | The Core.Scripting-008 rewrite broadened the BCL references list from a narrow allow-list (`System.Private.CoreLib` + `System.Linq` only) to the full `TRUSTED_PLATFORM_ASSEMBLIES` set filtered to `System.*` + `netstandard` + `Microsoft.Win… |
| Driver.Cli.Common-007 | High | Correctness & logic bugs | `src/Drivers/Cli/ZB.MOM.WW.OtOpcUa.Driver.Cli.Common/SnapshotFormatter.cs:129` | Commit `5a9c459` added `0x80550000u => "BadDeviceFailure"` to the `FormatStatus` shortlist, but `0x80550000` is the canonical OPC UA spec value for `BadSecurityPolicyRejected`, not `BadDeviceFailure`. The correct spec value for `BadDeviceF… |
| Core.Scripting-013 | Medium | Security | `ScriptEvaluator.cs:202-225` (`BuildWrapperSource`) | The synthesized wrapper pastes the user's source verbatim between `{` and `}` braces inside a static method body, with a `#line 1` directive and no escaping. The legacy `CSharpScript.CreateDelegate` path was robust to this because Roslyn's… |
| Core.Scripting-014 | Medium | Concurrency & thread safety | `CompiledScriptCache.cs:91-103` (`Clear`) | `Clear()` snapshots `_cache.Keys.ToArray()` then iterates, calling `TryRemove(key, out var lazy)` on each — the key-only overload, not the value-scoped one used in `GetOrCompile`'s catch block. Between the snapshot and a given `TryRemove`,… |
| Core.Scripting-016 | Medium | Performance & resource management | `src/Core/ZB.MOM.WW.OtOpcUa.Core.VirtualTags/VirtualTagEngine.cs:74-117`, `src/Core/ZB.MOM.WW.OtOpcUa.Core.ScriptedAlarms/ScriptedAlarmEngine.cs:139-182` | The Core.Scripting-008 resolution introduced `ScriptEvaluator.IDisposable` + `CompiledScriptCache.Clear()` that disposes each materialised evaluator before dropping its dictionary entry, so per-publish ALC accretion is no longer process-li… |
@@ -57,7 +56,6 @@ Findings with status `Open` or `In Progress`, ordered by severity.
| Driver.Galaxy-016 | Medium | Performance & resource management | `ZB.MOM.WW.OtOpcUa.Driver.Galaxy.csproj:43-47`, `libs/README.md:32-37` | The five new `PackageReference` versions declared in the csproj (`Google.Protobuf` 3.34.1, `Grpc.Core.Api` 2.76.0, `Grpc.Net.Client` 2.71.0, `Microsoft.Extensions.Logging.Abstractions` 10.0.0, `Polly` 8.5.2) do not all match what the vendo… |
| Core.ScriptedAlarms-013 | Low | Documentation & comments | `ScriptedAlarmEngine.cs:66-81` | The new internal test accessors `TryGetScratchReadCacheForTest` and `TryGetScratchContextForTest` (introduced by the Core.ScriptedAlarms-009 resolution at `0001cdd`) return the *live* per-alarm scratch — the same `Dictionary<string, DataVa… |
| Core.Scripting-015 | Low | Correctness & logic bugs | `ScriptEvaluator.cs:234-270` (`ToCSharpTypeName`) | `ToCSharpTypeName` is documented to handle nested types (`Outer+Inner``Outer.Inner`) via `Replace('+', '.')` for the non-generic path (line 269) but the generic path (line 263-266) constructs the name from `def.FullName!` then takes a s… |
| Driver.Cli.Common-008 | Low | Testing coverage | `tests/Drivers/Cli/ZB.MOM.WW.OtOpcUa.Driver.Cli.Common.Tests/SnapshotFormatterTests.cs:50-64` | Commit `5a9c459` adds a new `FormatStatus_names_native_driver_emitted_codes` `[Theory]` whose five `[InlineData]` rows are identical to five rows added to the existing `FormatStatus_names_well_known_status_codes` `[Theory]` in the same com… |
| Driver.Galaxy-017 | Low | Design-document adherence | `src/Drivers/ZB.MOM.WW.OtOpcUa.Driver.Galaxy/` (no source change), gateway proto contract | The vendored `MxGateway.Contracts.dll` only carries the OLD `MxGateway.Contracts.Proto[.Galaxy]` namespace (PE-namespace dump confirms — `MxGateway.Client`, `MxGateway.Contracts`, `MxGateway.Contracts.Proto`, `MxGateway.Contracts.Proto.Gal… |
| Driver.Galaxy-018 | Low | Documentation & comments | `libs/README.md:32-37`, `ZB.MOM.WW.OtOpcUa.Driver.Galaxy.csproj:40-47` | Several small documentation issues in the vendoring artefacts: 1. `libs/README.md` says "Versions match what the sibling repo's `ZB.MOM.WW.MxGateway.Contracts.csproj` uses" — but `ZB.MOM.WW.MxGateway.Contracts.csproj` only declares `Google… |
@@ -96,6 +94,7 @@ Findings with status `Resolved`, `Won't Fix`, or `Deferred`.
| Driver.AbLegacy-001 | High | Resolved | Correctness & logic bugs | `AbLegacyAddress.cs:54`, `AbLegacyDriver.cs:368-374` |
| Driver.AbLegacy-006 | High | Resolved | Concurrency & thread safety | `AbLegacyDriver.cs:107-158`, `AbLegacyDriver.cs:162-234`, `LibplctagLegacyTagRuntime.cs` |
| Driver.Cli.Common-001 | High | Resolved | Correctness & logic bugs | `src/Drivers/Cli/ZB.MOM.WW.OtOpcUa.Driver.Cli.Common/SnapshotFormatter.cs:106-119` |
| Driver.Cli.Common-007 | High | Resolved | Correctness & logic bugs | `src/Drivers/Cli/ZB.MOM.WW.OtOpcUa.Driver.Cli.Common/SnapshotFormatter.cs:129` |
| Driver.FOCAS-001 | High | Resolved | Correctness & logic bugs | `FocasDriverFactoryExtensions.cs:54-86`, `FocasDriverFactoryExtensions.cs:132-140` |
| Driver.FOCAS-002 | High | Resolved | Correctness & logic bugs | `WireFocasClient.cs:164-179`, `FocasDriver.cs:513`, `FocasDriver.cs:593` |
| Driver.Galaxy-002 | High | Resolved | Correctness & logic bugs | `Browse/DataTypeMap.cs:13`, `Runtime/MxValueDecoder.cs:9` |
@@ -331,6 +330,7 @@ Findings with status `Resolved`, `Won't Fix`, or `Deferred`.
| Driver.AbLegacy.Cli-007 | Low | Resolved | Testing coverage | `tests/Drivers/Cli/ZB.MOM.WW.OtOpcUa.Driver.AbLegacy.Cli.Tests/WriteCommandParseValueTests.cs` |
| Driver.Cli.Common-004 | Low | Resolved | Error handling & resilience | `src/Drivers/Cli/ZB.MOM.WW.OtOpcUa.Driver.Cli.Common/SnapshotFormatter.cs:68-70` |
| Driver.Cli.Common-006 | Low | Resolved | Documentation & comments | `src/Drivers/Cli/ZB.MOM.WW.OtOpcUa.Driver.Cli.Common/SnapshotFormatter.cs:71`, `src/Drivers/Cli/ZB.MOM.WW.OtOpcUa.Driver.Cli.Common/DriverCommandBase.cs:9` |
| Driver.Cli.Common-008 | Low | Resolved | Testing coverage | `tests/Drivers/Cli/ZB.MOM.WW.OtOpcUa.Driver.Cli.Common.Tests/SnapshotFormatterTests.cs:50-64` |
| Driver.FOCAS-007 | Low | Resolved | Error handling & resilience | `FocasDriver.cs:140-148`, `FocasDriver.cs:478-484`, `FocasDriver.cs:529-533`, `FocasAlarmProjection.cs:61-63` |
| Driver.FOCAS-008 | Low | Resolved | Performance & resource management | `FocasDriver.cs:201`, `FocasDriver.cs:253` |
| Driver.FOCAS-009 | Low | Resolved | Design-document adherence | `FocasDriverOptions.cs:110-115`, `FocasDriver.cs:468-486`, `FocasDriverFactoryExtensions.cs:75-80` |

View File

@@ -126,7 +126,7 @@ public static class SnapshotFormatter
0x803B0000u => "BadNotWritable",
0x803C0000u => "BadOutOfRange",
0x803D0000u => "BadNotSupported",
0x80550000u => "BadDeviceFailure",
0x808B0000u => "BadDeviceFailure",
0x80740000u => "BadTypeMismatch",
0x40000000u => "Uncertain",
_ => null,

View File

@@ -41,7 +41,7 @@ public static class AbCipStatusMapper
public const uint BadNotWritable = 0x803B0000u;
public const uint BadOutOfRange = 0x803C0000u;
public const uint BadNotSupported = 0x803D0000u;
public const uint BadDeviceFailure = 0x80550000u;
public const uint BadDeviceFailure = 0x808B0000u;
public const uint BadCommunicationError = 0x80050000u;
public const uint BadTimeout = 0x800A0000u;
public const uint BadTypeMismatch = 0x80730000u;

View File

@@ -16,7 +16,7 @@ public static class AbLegacyStatusMapper
public const uint BadNotWritable = 0x803B0000u;
public const uint BadOutOfRange = 0x803C0000u;
public const uint BadNotSupported = 0x803D0000u;
public const uint BadDeviceFailure = 0x80550000u;
public const uint BadDeviceFailure = 0x808B0000u;
public const uint BadCommunicationError = 0x80050000u;
public const uint BadTimeout = 0x800A0000u;
public const uint BadTypeMismatch = 0x80730000u;

View File

@@ -14,7 +14,7 @@ public static class FocasStatusMapper
public const uint BadNotWritable = 0x803B0000u;
public const uint BadOutOfRange = 0x803C0000u;
public const uint BadNotSupported = 0x803D0000u;
public const uint BadDeviceFailure = 0x80550000u;
public const uint BadDeviceFailure = 0x808B0000u;
public const uint BadCommunicationError = 0x80050000u;
public const uint BadTimeout = 0x800A0000u;
public const uint BadTypeMismatch = 0x80730000u;

View File

@@ -1511,7 +1511,7 @@ public sealed class ModbusDriver
private const uint StatusBadNotWritable = 0x803B0000u;
private const uint StatusBadOutOfRange = 0x803C0000u;
private const uint StatusBadNotSupported = 0x803D0000u;
private const uint StatusBadDeviceFailure = 0x80550000u;
private const uint StatusBadDeviceFailure = 0x808B0000u;
private const uint StatusBadCommunicationError = 0x80050000u;
/// <summary>

View File

@@ -69,7 +69,7 @@ public sealed class S7Driver(S7DriverOptions options, string driverInstanceId, I
/// <summary>OPC UA StatusCode used for socket / timeout / protocol-layer faults.</summary>
private const uint StatusBadCommunicationError = 0x80050000u;
/// <summary>OPC UA StatusCode used for a genuine device fault (CPU error, hardware fault).</summary>
private const uint StatusBadDeviceFailure = 0x80550000u;
private const uint StatusBadDeviceFailure = 0x808B0000u;
private readonly Dictionary<string, S7TagDefinition> _tagsByName = new(StringComparer.OrdinalIgnoreCase);
private readonly Dictionary<string, S7ParsedAddress> _parsedByName = new(StringComparer.OrdinalIgnoreCase);

View File

@@ -16,7 +16,7 @@ public static class TwinCATStatusMapper
public const uint BadNotWritable = 0x803B0000u;
public const uint BadOutOfRange = 0x803C0000u;
public const uint BadNotSupported = 0x803D0000u;
public const uint BadDeviceFailure = 0x80550000u;
public const uint BadDeviceFailure = 0x808B0000u;
public const uint BadCommunicationError = 0x80050000u;
public const uint BadTimeout = 0x800A0000u;
public const uint BadTypeMismatch = 0x80730000u;

View File

@@ -39,7 +39,9 @@ public sealed class SnapshotFormatterTests
[InlineData(0x803B0000u, "BadNotWritable")]
[InlineData(0x803C0000u, "BadOutOfRange")]
[InlineData(0x803D0000u, "BadNotSupported")]
[InlineData(0x80550000u, "BadDeviceFailure")]
// Driver.Cli.Common-007: corrected from 0x80550000 (which is actually
// BadSecurityPolicyRejected) to the canonical OPC UA spec value 0x808B0000.
[InlineData(0x808B0000u, "BadDeviceFailure")]
[InlineData(0x80740000u, "BadTypeMismatch")]
[InlineData(0x40000000u, "Uncertain")]
public void FormatStatus_names_well_known_status_codes(uint status, string expectedName)
@@ -47,22 +49,6 @@ public sealed class SnapshotFormatterTests
SnapshotFormatter.FormatStatus(status).ShouldBe($"0x{status:X8} ({expectedName})");
}
[Theory]
// Driver.FOCAS.Cli-005 follow-up (Driver.Cli.Common): the FOCAS / AbCip / AbLegacy mappers
// emit these five codes — they previously rendered only as severity-class "Bad" because the
// shortlist did not name them, defeating the operator workflow that docs/Driver.*.Cli.md
// promise (read the BadDeviceFailure / BadNotWritable / ... name straight off probe/write
// output). Pin them named so the docs stay accurate.
[InlineData(0x80020000u, "BadInternalError")]
[InlineData(0x803B0000u, "BadNotWritable")]
[InlineData(0x803C0000u, "BadOutOfRange")]
[InlineData(0x803D0000u, "BadNotSupported")]
[InlineData(0x80550000u, "BadDeviceFailure")]
public void FormatStatus_names_native_driver_emitted_codes(uint status, string expectedName)
{
SnapshotFormatter.FormatStatus(status).ShouldContain($"({expectedName})");
}
[Theory]
// Regression for Driver.Cli.Common-001: these codes were previously mapped to the
// wrong names. The hex values below are what the buggy shortlist used; they must
@@ -71,6 +57,10 @@ public sealed class SnapshotFormatterTests
[InlineData(0x80070000u, "BadNoCommunication")] // was mislabelled BadNoCommunication
[InlineData(0x80080000u, "BadWaitingForInitialData")] // was mislabelled BadWaitingForInitialData
[InlineData(0x80350000u, "BadNodeIdInvalid")] // was mislabelled BadNodeIdInvalid
// Driver.Cli.Common-007: 0x80550000 is BadSecurityPolicyRejected per spec, not
// BadDeviceFailure (which is 0x808B0000). The buggy shortlist + the six native-
// protocol mappers all had it wrong; this row pins it as a regression guard.
[InlineData(0x80550000u, "BadDeviceFailure")]
public void FormatStatus_does_not_apply_pre_fix_wrong_names(uint status, string wrongName)
{
SnapshotFormatter.FormatStatus(status).ShouldNotContain(wrongName);

View File

@@ -27,7 +27,7 @@ public sealed class ExceptionInjectionTests(ModbusSimulatorFixture sim)
private const uint StatusGood = 0u;
private const uint StatusBadOutOfRange = 0x803C0000u;
private const uint StatusBadNotSupported = 0x803D0000u;
private const uint StatusBadDeviceFailure = 0x80550000u;
private const uint StatusBadDeviceFailure = 0x808B0000u;
private const uint StatusBadCommunicationError = 0x80050000u;
private void SkipUnlessInjectorLive()

View File

@@ -18,9 +18,9 @@ public sealed class ModbusExceptionMapperTests
[InlineData((byte)0x01, 0x803D0000u)] // Illegal Function → BadNotSupported
[InlineData((byte)0x02, 0x803C0000u)] // Illegal Data Address → BadOutOfRange
[InlineData((byte)0x03, 0x803C0000u)] // Illegal Data Value → BadOutOfRange
[InlineData((byte)0x04, 0x80550000u)] // Server Failure → BadDeviceFailure
[InlineData((byte)0x05, 0x80550000u)] // Acknowledge (long op) → BadDeviceFailure
[InlineData((byte)0x06, 0x80550000u)] // Server Busy → BadDeviceFailure
[InlineData((byte)0x04, 0x808B0000u)] // Server Failure → BadDeviceFailure (Driver.Cli.Common-007)
[InlineData((byte)0x05, 0x808B0000u)] // Acknowledge (long op) → BadDeviceFailure
[InlineData((byte)0x06, 0x808B0000u)] // Server Busy → BadDeviceFailure
[InlineData((byte)0x0A, 0x80050000u)] // Gateway path unavailable → BadCommunicationError
[InlineData((byte)0x0B, 0x80050000u)] // Gateway target failed to respond → BadCommunicationError
[InlineData((byte)0xFF, 0x80020000u)] // Unknown code → BadInternalError fallback
@@ -61,7 +61,7 @@ public sealed class ModbusExceptionMapperTests
[new WriteRequest("T", (short)42)],
TestContext.Current.CancellationToken);
writes[0].StatusCode.ShouldBe(0x80550000u, "FC06 returning exception 04 (CPU in PROGRAM mode) maps to BadDeviceFailure");
writes[0].StatusCode.ShouldBe(0x808B0000u, "FC06 returning exception 04 (CPU in PROGRAM mode) maps to BadDeviceFailure");
}
private sealed class NonModbusFailureTransport : IModbusTransport