Auto: ablegacy-11 — RSLogix 500/PLC-5 CSV symbol import

Closes #254

tests/ZB.MOM.WW.OtOpcUa.Driver.AbLegacy.Tests/Import/AbLegacyDriverFactoryAddRsLogixImportTests.cs

@@ -0,0 +1,82 @@
+using System.IO;
+using Shouldly;
+using Xunit;
+using ZB.MOM.WW.OtOpcUa.Driver.AbLegacy;
+using ZB.MOM.WW.OtOpcUa.Driver.AbLegacy.PlcFamilies;
+
+namespace ZB.MOM.WW.OtOpcUa.Driver.AbLegacy.Tests.Import;
+
+/// <summary>
+///     Coverage for <see cref="AbLegacyDriverFactoryExtensions.AddRsLogixImport"/> — the
+///     extension method that opens a CSV file and concatenates the resulting tag definitions
+///     onto an existing <see cref="AbLegacyDriverOptions"/>.
+/// </summary>
+[Trait("Category", "Unit")]
+public sealed class AbLegacyDriverFactoryAddRsLogixImportTests
+{
+    [Fact]
+    public void AddRsLogixImport_appends_tags_and_preserves_existing_options()
+    {
+        // Existing options have one device + one hand-rolled tag. The importer should
+        // append on top — never replace — so the device + the original tag survive.
+        var path = Path.Combine(Path.GetTempPath(), $"rslogix-import-{Guid.NewGuid():N}.csv");
+        File.WriteAllText(path, """
+            Symbol,Address,Description,DataType,Scope
+            New1,N7:0,desc,INT,Global
+            New2,F8:0,desc,REAL,Global
+            """);
+        try
+        {
+            var existingTag = new AbLegacyTagDefinition(
+                Name: "Manual",
+                DeviceHostAddress: "ab://10.0.0.1/1,0",
+                Address: "S:0",
+                DataType: AbLegacyDataType.Int);
+            var options = new AbLegacyDriverOptions
+            {
+                Devices = [new AbLegacyDeviceOptions("ab://10.0.0.1/1,0", AbLegacyPlcFamily.Slc500)],
+                Tags = [existingTag],
+            };
+
+            var updated = options.AddRsLogixImport(path, "ab://10.0.0.1/1,0", out var result);
+
+            // Imported counts surface on the result.
+            result.ParsedCount.ShouldBe(2);
+
+            // Devices + the original Manual tag are preserved on the returned options.
+            updated.Devices.Count.ShouldBe(1);
+            updated.Tags.Count.ShouldBe(3);
+            updated.Tags[0].Name.ShouldBe("Manual");
+            updated.Tags[1].Name.ShouldBe("New1");
+            updated.Tags[2].Name.ShouldBe("New2");
+
+            // Original options object is unchanged (immutability guarantee).
+            options.Tags.Count.ShouldBe(1);
+        }
+        finally
+        {
+            try { File.Delete(path); } catch { /* best-effort */ }
+        }
+    }
+
+    [Fact]
+    public void AddRsLogixImportWithResult_returns_tuple()
+    {
+        var path = Path.Combine(Path.GetTempPath(), $"rslogix-import-{Guid.NewGuid():N}.csv");
+        File.WriteAllText(path, """
+            Symbol,Address,Description,DataType,Scope
+            T,N7:0,desc,INT,Global
+            """);
+        try
+        {
+            var options = new AbLegacyDriverOptions();
+            var (updated, result) = options.AddRsLogixImportWithResult(path, "ab://10.0.0.1/1,0");
+            result.ParsedCount.ShouldBe(1);
+            updated.Tags.Count.ShouldBe(1);
+        }
+        finally
+        {
+            try { File.Delete(path); } catch { /* best-effort */ }
+        }
+    }
+}