fix(template-engine): resolve TemplateEngine-001/003/004/005, re-triage 002 — recursive composed flattening, fixed-field guard, alarm script refs, dead collision query

tests/ScadaLink.TemplateEngine.Tests/TemplateServiceTests.cs

@@ -60,6 +60,23 @@ public class TemplateServiceTests
         Assert.Equal(1, result.Value.ParentTemplateId);
     }
 
+    [Fact]
+    public async Task CreateTemplate_WithParent_DoesNotRunDeadCollisionQuery()
+    {
+        // A freshly created child has no members of its own, and the parent's
+        // members were already collision-validated when they were added — so
+        // create-time collision detection on a child is a guaranteed no-op.
+        // The previous code allocated an unused full-table read; the fix
+        // removes it. This guards against the dead query being reintroduced.
+        var parent = new Template("Base") { Id = 1 };
+        _repoMock.Setup(r => r.GetTemplateByIdAsync(1, It.IsAny<CancellationToken>())).ReturnsAsync(parent);
+
+        var result = await _service.CreateTemplateAsync("Child", null, 1, "admin");
+
+        Assert.True(result.IsSuccess);
+        _repoMock.Verify(r => r.GetAllTemplatesAsync(It.IsAny<CancellationToken>()), Times.Never);
+    }
+
     [Fact]
     public async Task CreateTemplate_NonexistentParent_Fails()
     {
@@ -668,6 +685,54 @@ public class TemplateServiceTests
         Assert.True(result.Value.IsLocked);
     }
 
+    [Fact]
+    public async Task UpdateAttribute_UnlockedAttribute_DataTypeChangeRejected()
+    {
+        // An unlocked attribute must still not be able to change its fixed DataType.
+        var existing = new TemplateAttribute("Temperature")
+        {
+            Id = 1, TemplateId = 1, DataType = DataType.Float, IsLocked = false
+        };
+        _repoMock.Setup(r => r.GetTemplateAttributeByIdAsync(1, It.IsAny<CancellationToken>())).ReturnsAsync(existing);
+        var template = new Template("Pump") { Id = 1 };
+        _repoMock.Setup(r => r.GetTemplateByIdAsync(1, It.IsAny<CancellationToken>())).ReturnsAsync(template);
+
+        var proposed = new TemplateAttribute("Temperature")
+        {
+            DataType = DataType.Int32, IsLocked = false, Value = "42"
+        };
+        var result = await _service.UpdateAttributeAsync(1, proposed, "admin");
+
+        Assert.True(result.IsFailure);
+        Assert.Contains("DataType", result.Error);
+        // The fixed field must not have been mutated.
+        Assert.Equal(DataType.Float, existing.DataType);
+    }
+
+    [Fact]
+    public async Task UpdateAttribute_UnlockedAttribute_DataSourceReferenceChangeRejected()
+    {
+        var existing = new TemplateAttribute("Temperature")
+        {
+            Id = 1, TemplateId = 1, DataType = DataType.Float, IsLocked = false,
+            DataSourceReference = "/Motor/Temp"
+        };
+        _repoMock.Setup(r => r.GetTemplateAttributeByIdAsync(1, It.IsAny<CancellationToken>())).ReturnsAsync(existing);
+        var template = new Template("Pump") { Id = 1 };
+        _repoMock.Setup(r => r.GetTemplateByIdAsync(1, It.IsAny<CancellationToken>())).ReturnsAsync(template);
+
+        var proposed = new TemplateAttribute("Temperature")
+        {
+            DataType = DataType.Float, IsLocked = false, Value = "42",
+            DataSourceReference = "/Motor/Other"
+        };
+        var result = await _service.UpdateAttributeAsync(1, proposed, "admin");
+
+        Assert.True(result.IsFailure);
+        Assert.Contains("DataSourceReference", result.Error);
+        Assert.Equal("/Motor/Temp", existing.DataSourceReference);
+    }
+
     [Fact]
     public async Task UpdateAttribute_ParentLocked_CannotOverride()
     {