LayoutTestExecutor refactoring

Source/QuestPDF.LayoutTests/TestEngine/LayoutTest.cs

@@ -136,82 +136,10 @@ internal class LayoutTest
         var container = new Container();
         container.Element(handler);
 
-        TestResult.GeneratedLayout = GenerateResult(TestResult.PageSize, container);
+        TestResult.GeneratedLayout = LayoutTestExecutor.Execute(TestResult.PageSize, container);
         
         return this;
     }
-
-    private static ICollection<LayoutTestResult.PageLayoutSnapshot> GenerateResult(Size pageSize, Container container)
-    {
-        // inject dependencies
-        var pageContext = new PageContext();
-        pageContext.ResetPageNumber();
-
-        var canvas = new PreviewerCanvas();
-        
-        container.InjectDependencies(pageContext, canvas);
-        
-        // distribute global state
-        container.ApplyInheritedAndGlobalTexStyle(TextStyle.Default);
-        container.ApplyContentDirection(ContentDirection.LeftToRight);
-        container.ApplyDefaultImageConfiguration(DocumentSettings.Default.ImageRasterDpi, DocumentSettings.Default.ImageCompressionQuality, true);
-        
-        // render
-        container.VisitChildren(x => (x as IStateResettable)?.ResetState());
-        
-        canvas.BeginDocument();
-
-        var pageSizes = new List<Size>();
-        
-        while(true)
-        {
-            var spacePlan = container.Measure(pageSize);
-            pageSizes.Add(spacePlan);
-            
-            if (spacePlan.Type == SpacePlanType.Wrap)
-            {
-                throw new Exception();
-            }
-
-            try
-            {
-                canvas.BeginPage(pageSize);
-                container.Draw(pageSize);
-                
-                pageContext.IncrementPageNumber();
-            }
-            catch (Exception exception)
-            {
-                canvas.EndDocument();
-                throw new Exception();
-            }
-
-            canvas.EndPage();
-
-            if (spacePlan.Type == SpacePlanType.FullRender)
-                break;
-        }
-        
-        // extract results
-        var mocks = container.ExtractElementsOfType<ElementMock>().Select(x => x.Value); // mock cannot contain another mock, flat structure
-
-        return mocks
-            .SelectMany(x => x.DrawingCommands)
-            .GroupBy(x => x.PageNumber)
-            .Select(x => new LayoutTestResult.PageLayoutSnapshot
-            {
-                RequiredArea = pageSizes[x.Key - 1],
-                MockPositions = x
-                    .Select(y => new LayoutTestResult.MockLayoutPosition
-                    {
-                        MockId = y.MockId,
-                        Size = y.Size,
-                        Position = y.Position
-                    })
-                    .ToList()
-            })
-            .ToList();
-    }
     
     public void ExpectWrap()
     {

Source/QuestPDF.LayoutTests/TestEngine/LayoutTestException.cs

@@ -0,0 +1,14 @@
+namespace QuestPDF.LayoutTests.TestEngine;
+
+public class LayoutTestException : Exception
+{
+    internal LayoutTestException(string message) : base(message)
+    {
+            
+    }
+    
+    internal LayoutTestException(string message, Exception innerException) : base(message, innerException)
+    {
+            
+    }
+}

Source/QuestPDF.LayoutTests/TestEngine/LayoutTestExecutor.cs

@@ -0,0 +1,91 @@
+using QuestPDF.Drawing;
+using QuestPDF.Drawing.Proxy;
+using QuestPDF.Elements;
+using QuestPDF.Helpers;
+using QuestPDF.Infrastructure;
+
+namespace QuestPDF.LayoutTests.TestEngine;
+
+internal class LayoutTestExecutor
+{
+    public static ICollection<LayoutTestResult.PageLayoutSnapshot> Execute(Size pageSize, Container container)
+    {
+        var pageSizes = new List<Size>();
+        GenerateDocument();
+        return CollectMockInformation();
+
+        void GenerateDocument()
+        {
+            // inject dependencies
+            var pageContext = new PageContext();
+            pageContext.ResetPageNumber();
+
+            var canvas = new PreviewerCanvas();
+        
+            container.InjectDependencies(pageContext, canvas);
+        
+            // distribute global state
+            container.ApplyInheritedAndGlobalTexStyle(TextStyle.Default);
+            container.ApplyContentDirection(ContentDirection.LeftToRight);
+            container.ApplyDefaultImageConfiguration(DocumentSettings.Default.ImageRasterDpi, DocumentSettings.Default.ImageCompressionQuality, true);
+        
+            // render
+            container.VisitChildren(x => (x as IStateResettable)?.ResetState());
+        
+            canvas.BeginDocument();
+        
+            while(true)
+            {
+                var spacePlan = container.Measure(pageSize);
+                pageSizes.Add(spacePlan);
+
+                if (spacePlan.Type == SpacePlanType.Wrap)
+                {
+                    canvas.EndDocument();
+                    throw new LayoutTestException("Provided layout generates infinite document");
+                }
+
+                try
+                {
+                    canvas.BeginPage(pageSize);
+                    container.Draw(pageSize);
+                
+                    pageContext.IncrementPageNumber();
+                }
+                catch (Exception exception)
+                {
+                    canvas.EndDocument();
+                    throw new LayoutTestException("Exception occured during layout execution", exception);
+                }
+
+                canvas.EndPage();
+
+                if (spacePlan.Type == SpacePlanType.FullRender)
+                    break;
+            }
+        }
+
+        ICollection<LayoutTestResult.PageLayoutSnapshot> CollectMockInformation()
+        {
+            // mock cannot contain another mock, flat structure
+            var mocks = container.ExtractElementsOfType<ElementMock>().Select(x => x.Value); 
+
+            return mocks
+                .SelectMany(x => x.DrawingCommands)
+                .GroupBy(x => x.PageNumber)
+                .Select(x => new LayoutTestResult.PageLayoutSnapshot
+                {
+                    RequiredArea = pageSizes[x.Key - 1],
+                    MockPositions = x
+                        .Select(y => new LayoutTestResult.MockLayoutPosition
+                        {
+                            MockId = y.MockId,
+                            Size = y.Size,
+                            Position = y.Position
+                        })
+                        .ToList()
+                })
+                .ToList();
+        }
+    }
+}