Test: toggle states keep their margins

tests/ThemeToggleStatesTests.cs

@@ -0,0 +1,44 @@
+namespace Cthangover.Tools.Tests
+{
+    using Cthangover.Core.Mods.Testing;
+    using Cthangover.Core.UI.Theming;
+    using Godot;
+
+    /// <summary>A checked box or toggle under the mouse keeps the margins of its other states, so its label never jumps.</summary>
+    public class ThemeToggleStatesTests
+    {
+        private static readonly string[] States = { "normal", "hover", "pressed", "hover_pressed", "disabled" };
+
+        [ModTest("theme/toggle_states_keep_their_margins")]
+        static void ToggleStatesKeepTheirMargins(ModTestContext ctx)
+        {
+            // In the tree: styles are looked up through the theme owner only there.
+            var theme = CthangoverTheme.Build();
+            var root = ((SceneTree)Engine.GetMainLoop()).Root;
+            var controls = new (string What, Button Control)[]
+            {
+                ("CheckBox", new CheckBox()),
+                ("toggle Button", new Button { ToggleMode = true }),
+                ("tab", new Button { ToggleMode = true, ThemeTypeVariation = CthangoverTheme.TabVariation }),
+                ("primary", new Button { ToggleMode = true, ThemeTypeVariation = CthangoverTheme.PrimaryVariation }),
+                ("danger", new Button { ToggleMode = true, ThemeTypeVariation = CthangoverTheme.DangerVariation }),
+                ("icon", new Button { ToggleMode = true, ThemeTypeVariation = CthangoverTheme.IconVariation }),
+                ("ribbon", new Button { ToggleMode = true, ThemeTypeVariation = CthangoverTheme.RibbonVariation }),
+                ("OptionButton", new OptionButton()),
+            };
+            foreach (var (what, control) in controls)
+            {
+                control.Theme = theme;
+                root.AddChild(control);
+                var normal = control.GetThemeStylebox("normal");
+                foreach (var state in States)
+                {
+                    var box = control.GetThemeStylebox(state);
+                    ModAssert.CloseTo(normal.ContentMarginLeft, box.ContentMarginLeft, what: $"{what} {state}: left margin");
+                    ModAssert.CloseTo(normal.ContentMarginRight, box.ContentMarginRight, what: $"{what} {state}: right margin");
+                }
+                control.Free();
+            }
+        }
+    }
+}