test(config): add grid-style silent-drop guards

SemiStep/SemiStep.Tests/Core/Configuration/GridStyleEditorFacadeTests.cs

@@ -55,6 +55,19 @@ public async Task SaveThenLoad_RoundTrips()
 		reloaded.Should().Be(original);
 	}
 
+	[Fact]
+	public async Task SaveThenLoad_DistinctFixture_PreservesEveryMappedField()
+	{
+		using var tempDir = new TempDirectory();
+		var facade = new GridStyleEditorFacade();
+
+		facade.Save(tempDir.Path, GridStyleOptionsTestData.Distinct()).IsSuccess.Should().BeTrue();
+
+		var reloaded = (await facade.Load(tempDir.Path)).Value;
+
+		reloaded.Should().Be(GridStyleOptionsTestData.Distinct());
+	}
+
 	[Fact]
 	public async Task Validate_ShippedRecord_ReturnsOk()
 	{

SemiStep/SemiStep.Tests/Helpers/GridStyleOptionsTestData.cs

@@ -0,0 +1,100 @@
+using SemiStep.Core.Configuration;
+
+namespace SemiStep.Tests.Helpers;
+
+/// <summary>
+/// Shared test fixture for the grid-style anti-regression guards. <see cref="Distinct"/> returns a
+/// <see cref="GridStyleOptions"/> in which every surfaced field holds a distinct, valid, and
+/// exactly-representable value, so that a dropped or cross-wired Seed/BuildRecord/mapper line makes
+/// exactly one field mismatch. Colors are 53 mutually-distinct UPPERCASE opaque #RRGGBB literals
+/// (equality is string equality; <c>ToHex</c> emits X2). Numerics are integers or clean halves so the
+/// int↔decimal and double↔decimal conversions are exact. All five italics are <c>true</c> — the one
+/// kind whose type default (<c>false</c>) can equal a fixture value — so a dropped italic Seed line
+/// surfaces as false ≠ true. <see cref="GridStyleOptions.Orientation"/> is the non-default value, which
+/// proves BuildRecord preserves the unsurfaced field through <c>with</c>.
+/// </summary>
+public static class GridStyleOptionsTestData
+{
+	public static GridStyleOptions Distinct()
+	{
+		return new GridStyleOptions(
+			FontFamily: "Distinct Test Font",
+			HeaderFontSize: 13,
+			HeaderFontWeight: 300,
+			HeaderItalic: true,
+			CellFontSize: 11,
+			CellFontWeight: 800,
+			CellItalic: true,
+			CellPaddingLeft: 6.5,
+			CellPaddingTop: 4.5,
+			CellPaddingRight: 7.5,
+			CellPaddingBottom: 3.5,
+			RowHeight: 28.5,
+			SelectionBackgroundColor: "#010101",
+			SelectionForegroundColor: "#020202",
+			CellChangedColor: "#030303",
+			CellChangedSelectedColor: "#040404",
+			DisabledCellDepth0Color: "#050505",
+			DisabledCellDepth1Color: "#060606",
+			DisabledCellDepth2Color: "#070707",
+			DisabledCellDepth3Color: "#080808",
+			DisabledCellDepth0PastColor: "#090909",
+			DisabledCellDepth1PastColor: "#0A0A0A",
+			DisabledCellDepth2PastColor: "#0B0B0B",
+			DisabledCellDepth3PastColor: "#0C0C0C",
+			DisabledCellSelectedColor: "#0D0D0D",
+			DisabledCellForegroundColor: "#0E0E0E",
+			ReadOnlyCellDepth0Color: "#0F0F0F",
+			ReadOnlyCellDepth1Color: "#101010",
+			ReadOnlyCellDepth2Color: "#111111",
+			ReadOnlyCellDepth3Color: "#121212",
+			ReadOnlyCellDepth0PastColor: "#131313",
+			ReadOnlyCellDepth1PastColor: "#141414",
+			ReadOnlyCellDepth2PastColor: "#151515",
+			ReadOnlyCellDepth3PastColor: "#161616",
+			ReadOnlyCellSelectedColor: "#171717",
+			ReadOnlyCellForegroundColor: "#181818",
+			GridLineColor: "#191919",
+			StatusBarBackgroundColor: "#1A1A1A",
+			StatusBarForegroundColor: "#1B1B1B",
+			StatusBarPadding: 5.5,
+			StatusBarItemSpacing: 10.5,
+			StatusBarFontSize: 17,
+			StatusBarFontWeight: 500,
+			StatusBarItalic: true,
+			StatusBarTimerLabelFontSize: 19,
+			StatusBarTimerLabelFontWeight: 600,
+			StatusBarTimerLabelItalic: true,
+			StatusBarTimerValueFontSize: 23,
+			StatusBarTimerValueFontWeight: 700,
+			StatusBarTimerValueItalic: true,
+			ValidationPanelBackgroundColor: "#1C1C1C",
+			ValidationPanelForegroundColor: "#1D1D1D",
+			ValidationPanelErrorColor: "#1E1E1E",
+			ValidationPanelWarningColor: "#1F1F1F",
+			ValidationPanelMaxHeight: 150.5,
+			ExecutionDepth0Color: "#202020",
+			ExecutionDepth1Color: "#212121",
+			ExecutionDepth2Color: "#222222",
+			ExecutionDepth3Color: "#232323",
+			ExecutionDepth0PastColor: "#242424",
+			ExecutionDepth1PastColor: "#252525",
+			ExecutionDepth2PastColor: "#262626",
+			ExecutionDepth3PastColor: "#272727",
+			ExecutionCurrentStepMarkerColor: "#282828",
+			InfoColor: "#292929",
+			ConnectedColor: "#2A2A2A",
+			DisconnectedColor: "#2B2B2B",
+			LocalModeColor: "#2C2C2C",
+			ConnectingColor: "#2D2D2D",
+			PanelBackgroundColor: "#2E2E2E",
+			PanelHeaderBackgroundColor: "#2F2F2F",
+			SubtleBorderColor: "#303030",
+			SeparatorColor: "#313131",
+			SecondaryForegroundColor: "#323232",
+			GridBorderColor: "#333333",
+			GridBackgroundColor: "#343434",
+			HeaderForegroundColor: "#353535",
+			Orientation: GridOrientation.ColumnsAsSteps);
+	}
+}

SemiStep/SemiStep.Tests/UI/StyleEditor/GridStyleEditorViewModelTests.cs

@@ -1,6 +1,8 @@
 using System;
+using System.Collections.Generic;
 using System.Reactive;
 using System.Reactive.Linq;
+using System.Reflection;
 using System.Text.RegularExpressions;
 
 using Avalonia.Headless.XUnit;
@@ -31,36 +33,77 @@ namespace SemiStep.Tests.UI.StyleEditor;
 public sealed class GridStyleEditorViewModelTests
 {
 	private const string ConfigDir = @"C:\does-not-exist";
+	private const int SurfacedEditablePropertyCount = 77;
 
 	[AvaloniaFact]
-	public void Seed_PopulatesColorAndNumericProps_FromRecord()
+	public void Seed_PopulatesEverySurfacedProperty_FromDistinctFixture()
 	{
-		var source = GridStyleOptions.Default with
+		var fixture = GridStyleOptionsTestData.Distinct();
+		var viewModel = CreateViewModel(fixture);
+
+		var properties = EditableProperties();
+		properties.Should().HaveCount(
+			SurfacedEditablePropertyCount,
+			"the fixture must exercise every surfaced editable property");
+
+		foreach (var property in properties)
 		{
-			StatusBarFontSize = 15,
-			StatusBarTimerValueFontSize = 30
-		};
-		var viewModel = CreateViewModel(source);
+			var recordValue = RecordField(property).GetValue(fixture);
+			var actual = property.GetValue(viewModel);
+			var because = $"property {property.Name} must be seeded from the fixture";
+
+			if (property.PropertyType == typeof(Color))
+			{
+				actual.Should().Be(HexColor.Parse((string)recordValue!), because);
+			}
+			else if (property.PropertyType == typeof(decimal?))
+			{
+				// The record's int font sizes and double paddings box under reflection; a direct
+				// (decimal) cast on a boxed int throws, so normalize both sides via Convert.ToDecimal.
+				Convert.ToDecimal(actual).Should().Be(Convert.ToDecimal(recordValue), because);
+			}
+			else
+			{
+				actual.Should().Be(recordValue, because);
+			}
+		}
+	}
 
-		viewModel.CellFontSize.Should().Be(source.CellFontSize);
-		viewModel.RowHeight.Should().Be((decimal)source.RowHeight);
-		viewModel.ValidationPanelMaxHeight.Should().Be((decimal)source.ValidationPanelMaxHeight);
-		viewModel.StatusBarFontSize.Should().Be(15);
-		viewModel.StatusBarTimerValueFontSize.Should().Be(30);
+	[AvaloniaFact]
+	public void Seed_ThenBuildRecord_PreservesEveryFieldDistinctly()
+	{
+		var viewModel = CreateViewModel(GridStyleOptionsTestData.Distinct());
 
-		viewModel.SelectionBackground.Should().Be(Color.Parse(source.SelectionBackgroundColor));
-		viewModel.HeaderForeground.Should().Be(Color.Parse(source.HeaderForegroundColor));
+		viewModel.BuildRecord().Should().Be(GridStyleOptionsTestData.Distinct());
 	}
 
 	[AvaloniaFact]
-	public void Seed_RoundTripsShippedHexValues_Losslessly()
+	public void BuildRecord_PerturbingEachProperty_ChangesOnlyThatMappedField()
 	{
-		var source = GridStyleOptions.Default;
-		var viewModel = CreateViewModel(source);
+		var viewModel = CreateViewModel(GridStyleOptionsTestData.Distinct());
 
-		var record = viewModel.BuildRecord();
+		var properties = EditableProperties();
+		properties.Should().HaveCount(
+			SurfacedEditablePropertyCount,
+			"the perturbation guard must cover every surfaced editable property");
 
-		record.Should().Be(source);
+		foreach (var property in properties)
+		{
+			var seededValue = property.GetValue(viewModel);
+			var baseline = viewModel.BuildRecord();
+
+			property.SetValue(viewModel, Perturb(property, seededValue));
+			var built = viewModel.BuildRecord();
+
+			var mappedField = RecordField(property).Name;
+			var changedFields = ChangedRecordFields(baseline, built);
+			changedFields.Should().BeEquivalentTo(
+				new[] { mappedField },
+				$"editing {property.Name} must change exactly the {mappedField} record field");
+
+			// Restore the seeded value rather than reconstruct the VM: each ctor enumerates system fonts.
+			property.SetValue(viewModel, seededValue);
+		}
 	}
 
 	[AvaloniaFact]
@@ -385,6 +428,63 @@ private static GridStyleEditorViewModel CreateViewModel(GridStyleOptions source)
 			NullLogger<GridStyleEditorViewModel>.Instance);
 	}
 
+	private static IReadOnlyList<PropertyInfo> EditableProperties()
+	{
+		return typeof(GridStyleEditorViewModel).GetProperties()
+			.Where(property => property.GetMethod?.IsPublic == true && property.SetMethod?.IsPublic == true)
+			.ToList();
+	}
+
+	private static PropertyInfo RecordField(PropertyInfo viewModelProperty)
+	{
+		var fieldName = viewModelProperty.PropertyType == typeof(Color)
+			? viewModelProperty.Name + "Color"
+			: viewModelProperty.Name;
+
+		return typeof(GridStyleOptions).GetProperty(fieldName)
+			?? throw new InvalidOperationException($"No GridStyleOptions field maps to {viewModelProperty.Name}");
+	}
+
+	// Color perturbation stays opaque so ToHex changes; weights are unvalidated ints so any value round-trips.
+	private static object? Perturb(PropertyInfo property, object? current)
+	{
+		if (property.PropertyType == typeof(Color))
+		{
+			var color = (Color)current!;
+			return Color.FromArgb(255, (byte)(color.R ^ 1), color.G, color.B);
+		}
+
+		if (property.PropertyType == typeof(decimal?))
+		{
+			return (decimal?)current + 1;
+		}
+
+		if (property.PropertyType == typeof(int))
+		{
+			return (int)current! + 100;
+		}
+
+		if (property.PropertyType == typeof(bool))
+		{
+			return !(bool)current!;
+		}
+
+		if (property.PropertyType == typeof(string))
+		{
+			return (string)current! + " Perturbed";
+		}
+
+		throw new InvalidOperationException($"No perturbation defined for {property.Name} ({property.PropertyType})");
+	}
+
+	private static IReadOnlyList<string> ChangedRecordFields(GridStyleOptions baseline, GridStyleOptions candidate)
+	{
+		return typeof(GridStyleOptions).GetProperties()
+			.Where(property => !Equals(property.GetValue(baseline), property.GetValue(candidate)))
+			.Select(property => property.Name)
+			.ToList();
+	}
+
 	private static async Task ExecuteSwallowing(ReactiveCommand<Unit, bool> command)
 	{
 		try