Add conformance tests for the Decoration element

Source/QuestPDF.ConformanceTests/DecorationTests.cs

@@ -0,0 +1,93 @@
+using QuestPDF.ConformanceTests.TestEngine;
+using QuestPDF.Drawing;
+using QuestPDF.Fluent;
+using QuestPDF.Helpers;
+
+namespace QuestPDF.ConformanceTests;
+
+internal class DecorationTests : ConformanceTestBase
+{
+    protected override Document GetDocumentUnderTest()
+    {
+        QuestPDF.Settings.EnableDebugging = true;
+        
+        return Document
+            .Create(document =>
+            {
+                document.Page(page =>
+                {
+                    page.Size(600, 975);
+                    page.Margin(50);
+
+                    page.Content()
+                        .Decoration(decoration =>
+                        {
+                            decoration.Before()
+                                .Column(column =>
+                                {
+                                    column.Item()
+                                        .ShowOnce()
+                                        .Height(50)
+                                        .Width(200)
+                                        .SemanticImage("First page: decoration before")
+                                        .Image(Placeholders.Image);
+                                    
+                                    column.Item()
+                                        .SkipOnce()
+                                        .Text("Second page: decoration before");
+                                });
+                            
+                            decoration
+                                .Content()
+                                .PaddingVertical(25)
+                                .Column(column =>
+                                {
+                                    column.Spacing(25);
+                                    
+                                    foreach (var i in Enumerable.Range(1, 15))
+                                    {
+                                        column.Item()
+                                            .Width(200)
+                                            .Height(50)
+                                            .Background(Colors.Grey.Lighten3)
+                                            .AlignCenter()
+                                            .AlignMiddle()
+                                            .Text($"Item {i}");
+                                    }
+                                });
+                            
+                            decoration.After()
+                                .Column(column =>
+                                {
+                                    column.Item()
+                                        .ShowOnce()
+                                        .Height(50)
+                                        .Width(200)
+                                        .SemanticImage("First page: decoration after")
+                                        .Image(Placeholders.Image);
+                                    
+                                    column.Item()
+                                        .SkipOnce()
+                                        .Text("Second page: decoration after");
+                                });
+                        });
+                });
+            });
+    }
+
+    protected override SemanticTreeNode? GetExpectedSemanticTree()
+    {
+        return ExpectedSemanticTree.DocumentRoot(root =>
+        {
+            root.Child("Figure", figure => figure.Alt("First page: decoration before"));
+                
+            foreach (var i in Enumerable.Range(1, 10))
+                root.Child("P");
+                
+            root.Child("Figure", figure => figure.Alt("First page: decoration after"));
+            
+            foreach (var i in Enumerable.Range(1, 5))
+                root.Child("P");
+        });
+    }
+}