Fix #3383: more aggressively transform object initializers on structs

Author: siegfriedpammer

ICSharpCode.Decompiler.Tests/TestCases/Correctness/InitializerTests.cs

@@ -318,14 +318,6 @@ public static void CollectionInitializerInsideObjectInitializers()
 			};
 		}
 
-		public static void NotAStructInitializer_DefaultConstructor()
-		{
-			InitializerTests.StructData data = new InitializerTests.StructData();
-			data.Field = 1;
-			data.Property = 2;
-			InitializerTests.X(InitializerTests.Y(), data);
-		}
-
 		public static void StructInitializer_DefaultConstructor()
 		{
 			InitializerTests.X(InitializerTests.Y(), new InitializerTests.StructData {
@@ -334,14 +326,6 @@ public static void StructInitializer_DefaultConstructor()
 			});
 		}
 
-		public static void NotAStructInitializer_ExplicitConstructor()
-		{
-			InitializerTests.StructData data = new InitializerTests.StructData(0);
-			data.Field = 1;
-			data.Property = 2;
-			InitializerTests.X(InitializerTests.Y(), data);
-		}
-
 		public static void StructInitializer_ExplicitConstructor()
 		{
 			InitializerTests.X(InitializerTests.Y(), new InitializerTests.StructData(0) {

ICSharpCode.Decompiler.Tests/TestCases/Pretty/InitializerTests.cs

@@ -247,6 +247,51 @@ public Issue3392Type(object x)
 
 			}
 		}
+
+		private class StructInitPropertiesTest
+		{
+			private class TypeA
+			{
+				public int A { get; set; }
+				public int B { get; set; }
+			}
+
+			private struct TypeB
+			{
+				public int A { get; set; }
+				public int B { get; set; }
+			}
+
+			private struct TypeC
+			{
+				public int A { get; init; }
+				public int B { get; init; }
+			}
+
+			private static TypeA TestA()
+			{
+				return new TypeA {
+					A = 1,
+					B = 2
+				};
+			}
+
+			private static TypeB TestB()
+			{
+				return new TypeB {
+					A = 1,
+					B = 2
+				};
+			}
+
+			private static TypeC TestC()
+			{
+				return new TypeC {
+					A = 1,
+					B = 2
+				};
+			}
+		}
 #endif
 		#endregion
 
@@ -928,14 +973,6 @@ public static void CollectionInitializerInsideObjectInitializers()
 			});
 		}
 
-		public static void NotAStructInitializer_DefaultConstructor()
-		{
-			StructData structData = default(StructData);
-			structData.Field = 1;
-			structData.Property = 2;
-			X(Y(), structData);
-		}
-
 		public static void StructInitializer_DefaultConstructor()
 		{
 			X(Y(), new StructData {
@@ -956,14 +993,6 @@ public void InliningOfStFldTarget()
 			};
 		}
 
-		public static void NotAStructInitializer_ExplicitConstructor()
-		{
-			StructData structData = new StructData(0);
-			structData.Field = 1;
-			structData.Property = 2;
-			X(Y(), structData);
-		}
-
 		public static void StructInitializer_ExplicitConstructor()
 		{
 			X(Y(), new StructData(0) {

ICSharpCode.Decompiler/IL/Transforms/TransformCollectionAndObjectInitializers.cs

@@ -73,14 +73,6 @@ void IStatementTransform.Run(Block block, int pos, StatementTransformContext con
 					instType = newObjInst.Method.DeclaringType;
 					break;
 				case DefaultValue defaultVal:
-					if (defaultVal.ILStackWasEmpty && v.Kind == VariableKind.Local && !currentMethod.IsConstructor)
-					{
-						// on statement level (no other expressions on IL stack),
-						// prefer to keep local variables (but not stack slots),
-						// unless we are in a constructor (where inlining object initializers might be 
-						// critical for the base ctor call)
-						return;
-					}
 					instType = defaultVal.Type;
 					break;
 				case Call c when c.Method.FullNameIs("System.Activator", "CreateInstance") && c.Method.TypeArguments.Count == 1: