From 4d09d4522e2cbfbd1bdc9036084435d27ed30929 Mon Sep 17 00:00:00 2001
From: BDisp <bd.bdisp@gmail.com>
Date: Thu, 10 Jun 2021 20:31:57 +0100
Subject: [PATCH] Added a AllViewsTests unit test to test all Views derived
 class constructors.

---
 UnitTests/AllViewsTests.cs | 112 +++++++++++++++++++++++++++++++++++++
 1 file changed, 112 insertions(+)
 create mode 100644 UnitTests/AllViewsTests.cs

diff --git a/UnitTests/AllViewsTests.cs b/UnitTests/AllViewsTests.cs
new file mode 100644
index 000000000..913090e7a
--- /dev/null
+++ b/UnitTests/AllViewsTests.cs
@@ -0,0 +1,112 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Reflection;
+using Xunit;
+using System.IO;
+
+namespace Terminal.Gui.Views {
+	public class AllViewsTests {
+		[Fact]
+		public void AllViews_Tests_All_Constructors ()
+		{
+			Application.Init (new FakeDriver (), new FakeMainLoop (() => FakeConsole.ReadKey (true)));
+
+			foreach (var type in GetAllViewClassesCollection ()) {
+				Assert.True (Constructors_FullTest (type));
+			}
+
+			Application.Shutdown ();
+		}
+
+		public bool Constructors_FullTest (Type type)
+		{
+			foreach (var ctor in type.GetConstructors ()) {
+				if (type.IsGenericType && type.IsTypeDefinition) {
+					List<Type> gTypes = new List<Type> ();
+
+					foreach (var args in type.GetGenericArguments ()) {
+						gTypes.Add (typeof (object));
+					}
+					type = type.MakeGenericType (gTypes.ToArray ());
+
+					Assert.IsType (type, (View)Activator.CreateInstance (type));
+
+				} else {
+					ParameterInfo [] paramsInfo = ctor.GetParameters ();
+					Type paramType;
+					List<object> pTypes = new List<object> ();
+
+					if (type.IsGenericType) {
+						foreach (var args in type.GetGenericArguments ()) {
+							paramType = args.GetType ();
+							if (args.Name == "T") {
+								pTypes.Add (typeof (object));
+							} else {
+								AddArguments (paramType, pTypes);
+							}
+						}
+					}
+
+					foreach (var p in paramsInfo) {
+						paramType = p.ParameterType;
+						if (p.HasDefaultValue) {
+							pTypes.Add (p.DefaultValue);
+						} else {
+							AddArguments (paramType, pTypes);
+						}
+
+					}
+
+					if (type.IsGenericType && !type.IsTypeDefinition) {
+						Assert.IsType (type, (View)Activator.CreateInstance (type));
+					} else {
+						Assert.IsType (type, ctor.Invoke (pTypes.ToArray ()));
+					}
+				}
+			}
+
+			return true;
+		}
+
+		private static void AddArguments (Type paramType, List<object> pTypes)
+		{
+			if (paramType == typeof (Rect)) {
+				pTypes.Add (Rect.Empty);
+			} else if (paramType == typeof (NStack.ustring)) {
+				pTypes.Add (NStack.ustring.Empty);
+			} else if (paramType == typeof (int)) {
+				pTypes.Add (0);
+			} else if (paramType == typeof (bool)) {
+				pTypes.Add (true);
+			} else if (paramType.Name == "IList") {
+				pTypes.Add (new List<object> ());
+			} else if (paramType.Name == "View") {
+				var top = new Toplevel ();
+				var view = new View ();
+				top.Add (view);
+				pTypes.Add (view);
+			} else if (paramType.Name == "View[]") {
+				pTypes.Add (new View [] { });
+			} else if (paramType.Name == "Stream") {
+				pTypes.Add (new MemoryStream ());
+			} else if (paramType.Name == "String") {
+				pTypes.Add (string.Empty);
+			} else if (paramType.Name == "TreeView`1[T]") {
+				pTypes.Add (string.Empty);
+			} else {
+				pTypes.Add (null);
+			}
+		}
+
+		List<Type> GetAllViewClassesCollection ()
+		{
+			List<Type> types = new List<Type> ();
+			foreach (Type type in typeof (View).Assembly.GetTypes ()
+			 .Where (myType => myType.IsClass && !myType.IsAbstract && myType.IsPublic && myType.IsSubclassOf (typeof (View)))) {
+				types.Add (type);
+			}
+			return types;
+		}
+	}
+}