fix(abcip): CompactLogix native default connection size matches libplctag's Large Forward Open (found by T21 latency harness)

2026-10-07 19:34:30 -04:00
parent 2dc55ecb8f
commit c306c6f674
9 changed files with 101 additions and 22 deletions
@@ -44,7 +44,7 @@ public static class KnownProfiles
    public static readonly AbServerProfile CompactLogix = new(
        Family: AbCipPlcFamily.CompactLogix,
        ComposeProfile: "compactlogix",
-        Notes: "ab_server doesn't enforce the narrower ConnectionSize; driver-side profile caps it per PR 10.");
+        Notes: "Large Forward Open (4002) like libplctag since T21; ab_server accepts any size, so the regular-open fallback is unit-tested only.");

    /// <summary>Gets the Micro800 profile.</summary>
    public static readonly AbServerProfile Micro800 = new(
@@ -202,4 +202,26 @@ public sealed class AbCipDriverProbeTests
        result.Ok.ShouldBeTrue();
        result.Message!.ShouldContain("probe tag not found");
    }
+
+    /// <summary>
+    ///     T21: the probe builds its handle from the family profile, so a CompactLogix device with no
+    ///     ConnectionSize opens Large (4002) like libplctag; an explicit device ConnectionSize still wins.
+    /// </summary>
+    [Theory]
+    [InlineData("", 4002)]
+    [InlineData(",\"connectionSize\":504", 504)]
+    public async Task CompactLogix_probe_uses_the_profile_default_unless_the_device_overrides_it(string extra, int expected)
+    {
+        using var listener = new TcpListener(IPAddress.Loopback, 0);
+        listener.Start();
+        var port = ((IPEndPoint)listener.LocalEndpoint).Port;
+        var factory = new FakeAbCipTagFactory();
+
+        await new AbCipDriverProbe(factory).ProbeAsync(
+            $"{{\"devices\":[{{\"hostAddress\":\"ab://127.0.0.1:{port}/1,0\",\"plcFamily\":\"CompactLogix\"{extra}}}]}}",
+            TimeSpan.FromSeconds(3),
+            TestContext.Current.CancellationToken);
+
+        factory.Tags.Values.ShouldHaveSingleItem().CreationParams.ConnectionSize.ShouldBe(expected);
+    }
 }
@@ -106,7 +106,7 @@ public sealed class AbCipDriverTests
        AbCipPlcFamilyProfile.Micro800.SupportsRequestPacking.ShouldBeFalse();
        AbCipPlcFamilyProfile.Micro800.SupportsConnectedMessaging.ShouldBeFalse();

-        AbCipPlcFamilyProfile.CompactLogix.DefaultConnectionSize.ShouldBe(504);
+        AbCipPlcFamilyProfile.CompactLogix.DefaultConnectionSize.ShouldBe(4002); // Large, as libplctag opens it
        AbCipPlcFamilyProfile.GuardLogix.LibplctagPlcAttribute.ShouldBe("controllogix");
    }

@@ -117,6 +117,29 @@ public sealed class AbCipPerDeviceConnectionOptionsTests
        factory.Tags["Speed"].CreationParams.ConnectionSize.ShouldBe(4002);
    }

+    /// <summary>
+    ///     T21: a CompactLogix device with no override opens Large (4002), matching libplctag's
+    ///     <c>plc=compactlogix</c>; the per-device override still wins.
+    /// </summary>
+    [Theory]
+    [InlineData(null, 4002)]
+    [InlineData(504, 504)]
+    public async Task CompactLogix_ConnectionSize_defaults_to_large_unless_overridden(int? overrideSize, int expected)
+    {
+        var factory = new FakeAbCipTagFactory();
+        var drv = new AbCipDriver(new AbCipDriverOptions
+        {
+            Devices = [new AbCipDeviceOptions(Device, AbCipPlcFamily.CompactLogix, ConnectionSize: overrideSize)],
+            RawTags = AbCipRawTags.From(new AbCipTagDefinition("Speed", Device, "Speed", AbCipDataType.DInt)),
+            Probe = new AbCipProbeOptions { Enabled = false },
+        }, "drv-1", factory);
+        await drv.InitializeAsync("{}", CancellationToken.None);
+
+        await drv.ReadAsync(["Speed"], CancellationToken.None);
+
+        factory.Tags["Speed"].CreationParams.ConnectionSize.ShouldBe(expected);
+    }
+
    /// <summary>Verifies that AllowPacking and ConnectionSize round-trip correctly through JSON parsing.</summary>
    [Fact]
    public void AbCipDriverFactoryExtensions_ParseOptions_round_trips_AllowPacking_and_ConnectionSize()
@@ -40,22 +40,26 @@ public sealed class AbCipPlcFamilyTests

    // ---- CompactLogix ----

-    /// <summary>Verifies that the CompactLogix profile uses a narrower connection size than ControlLogix.</summary>
+    /// <summary>
+    ///     Verifies that the CompactLogix profile defaults to a Large Forward Open (4002), matching what
+    ///     libplctag opens for <c>plc=compactlogix</c>. A target that refuses Large falls back to a regular
+    ///     504 open inside CipConnection (pinned by the Ab.Transport CipConnectionTests fallback tests).
+    /// </summary>
    [Fact]
-    public void CompactLogix_profile_uses_narrower_connection_size()
+    public void CompactLogix_profile_defaults_to_a_large_forward_open_like_libplctag()
    {
        var p = AbCipPlcFamilyProfile.CompactLogix;
        p.LibplctagPlcAttribute.ShouldBe("compactlogix");
-        p.DefaultConnectionSize.ShouldBe(504); // 5069-L3x narrow-window safety
+        p.DefaultConnectionSize.ShouldBe(4002); // T21: 504 cost the native transport ~3x the round trips per poll
        p.DefaultCipPath.ShouldBe("1,0");
        p.SupportsRequestPacking.ShouldBeTrue();
        p.SupportsConnectedMessaging.ShouldBeTrue();
        p.MaxFragmentBytes.ShouldBe(500);
    }

-    /// <summary>Verifies that a CompactLogix device initializes with a narrow connection size.</summary>
+    /// <summary>Verifies that a CompactLogix device initializes with the Large connection size libplctag opens (T21).</summary>
    [Fact]
-    public async Task CompactLogix_device_initialises_with_narrow_ConnectionSize()
+    public async Task CompactLogix_device_initialises_with_large_ConnectionSize()
    {
        var drv = new AbCipDriver(new AbCipDriverOptions
        {
@@ -65,7 +69,7 @@ public sealed class AbCipPlcFamilyTests
        await drv.InitializeAsync("{}", CancellationToken.None);

        var profile = drv.GetDeviceState("ab://192.168.1.10/1,0")!.Profile;
-        profile.DefaultConnectionSize.ShouldBeLessThan(AbCipPlcFamilyProfile.ControlLogix.DefaultConnectionSize);
+        profile.DefaultConnectionSize.ShouldBe(4002);
        profile.MaxFragmentBytes.ShouldBeLessThan(AbCipPlcFamilyProfile.ControlLogix.MaxFragmentBytes);
    }