UiBox2 validation + standardisation

RELEASE-NOTES.md

@@ -35,7 +35,7 @@ END TEMPLATE-->
 
 ### Breaking changes
 
-*None yet*
+* Add validation to `UiBox2` to ensure the size is >= 0.
 
 ### New features
 

Robust.Client.Tests/Graphics/StyleBoxTest.cs

@@ -36,5 +36,21 @@ public void TestGetEnvelopBox()
                 styleBox.GetEnvelopBox(new Vector2(10, 10), new Vector2(50, 50), 2.0f),
                 Is.EqualTo(new UIBox2(10, 10, 80, 92)));
         }
+
+        [Test]
+        public void TestGetContentBoxClampsWhenMarginsExceedBaseBox()
+        {
+            var styleBox = new StyleBoxFlat
+            {
+                ContentMarginLeftOverride = 10,
+                ContentMarginTopOverride = 20,
+                ContentMarginRightOverride = 30,
+                ContentMarginBottomOverride = 40,
+            };
+
+            var contentBox = styleBox.GetContentBox(new UIBox2(0, 0, 5, 5), 1);
+
+            Assert.That(contentBox, Is.EqualTo(new UIBox2(10, 20, 10, 20)));
+        }
     }
 }

Robust.Client/Graphics/Drawing/StyleBox.cs

@@ -276,16 +276,16 @@ public Vector2 GetContentOffset(Vector2 basePosition, float uiScale)
         ///     Gets the box considered the "contents" of this style box, when drawn at a specific size. Input and output
         ///     boxes are in virtual pixels, though virtual pixels can also be used if the ui scale is set to 1.
         /// </summary>
-        /// <exception cref="ArgumentException">
-        ///     <paramref name="baseBox"/> is too small and the resultant box would have negative dimensions.
-        /// </exception>
         public UIBox2 GetContentBox(UIBox2 baseBox, float uiScale)
         {
             var left = baseBox.Left + GetContentMargin(Margin.Left) * uiScale;
             var top = baseBox.Top + GetContentMargin(Margin.Top) * uiScale;
             var right = baseBox.Right - GetContentMargin(Margin.Right) * uiScale;
             var bottom = baseBox.Bottom - GetContentMargin(Margin.Bottom) * uiScale;
 
+            right = MathF.Max(left, right);
+            bottom = MathF.Max(top, bottom);
+
             return new UIBox2(left, top, right, bottom);
         }
 

Robust.Shared.Maths.Tests/UIBox2_Test.cs

@@ -97,6 +97,32 @@ public void Box2EdgesConstructor([ValueSource(nameof(Sources))] (float, float, f
             Assert.That(box.Bottom, Is.EqualTo(bottom));
         }
 
+        [Test]
+        public void Box2ValidatesConstruction()
+        {
+            Assert.Multiple(() =>
+            {
+                Assert.Throws<ArgumentException>(() => new UIBox2(3, 4, -1, -2));
+                Assert.Throws<ArgumentException>(() => new UIBox2(new Vector2(3, 4), new Vector2(-1, -2)));
+            });
+        }
+
+        [Test]
+        public void Box2ValidatesProperties()
+        {
+            var box = new UIBox2(-1, -2, 3, 4);
+
+            Assert.Multiple(() =>
+            {
+                Assert.Throws<ArgumentOutOfRangeException>(() => box.Left = 4);
+                Assert.Throws<ArgumentOutOfRangeException>(() => box.Top = 5);
+                Assert.Throws<ArgumentOutOfRangeException>(() => box.Right = -2);
+                Assert.Throws<ArgumentOutOfRangeException>(() => box.Bottom = -3);
+                Assert.Throws<ArgumentOutOfRangeException>(() => box.TopLeft = new Vector2(4, 0));
+                Assert.Throws<ArgumentOutOfRangeException>(() => box.BottomRight = new Vector2(0, -3));
+            });
+        }
+
         [Test]
         public void Box2CornerVectorProperties([ValueSource(nameof(Sources))] (float, float, float, float) test)
         {