Fix #3703: Do not transform to a primary constructor if it's not public (or protected in abstract classes)

Author: siegfriedpammer

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

@@ -134,7 +134,7 @@ public class MethodCallInCtorInit
 		{
 			public MethodCallInCtorInit(ConsoleKey key)
 #if MCS5
-				: this(((int)key/*cast due to .constrained prefix*/).ToString())
+				: this(((int)key/*cast due to constrained. prefix*/).ToString())
 #else
 				: this(((int)key).ToString())
 #endif
@@ -286,6 +286,16 @@ public int Test()
 			}
 		}
 #endif
+
+		public struct My
+		{
+			private ClassWithConstantAndStaticCtor test;
+
+			internal My(ClassWithConstantAndStaticCtor a)
+			{
+				test = a;
+			}
+		}
 #endif
 	}
 }

ICSharpCode.Decompiler/CSharp/RecordDecompiler.cs

@@ -179,12 +179,15 @@ bool IsAutoSetter(IMethod method, [NotNullWhen(true)] out IField? field)
 			}
 
 			IMethod? guessedPrimaryCtor = null;
+			Accessibility expectedCtorAccessibility = recordTypeDef.IsAbstract ? Accessibility.Protected : Accessibility.Public;
 
 			foreach (var method in recordTypeDef.Methods)
 			{
 				cancellationToken.ThrowIfCancellationRequested();
 				if (method.IsStatic || !method.IsConstructor)
 					continue;
+				if (method.Accessibility != expectedCtorAccessibility)
+					continue;
 				if (IsCopyConstructor(method))
 				{
 					continue;

ICSharpCode.Decompiler/CSharp/Transforms/TransformFieldAndConstructorInitializers.cs

@@ -340,6 +340,8 @@ public bool Analyze(IEnumerable<AstNode> members)
 					}
 				}
 
+				Accessibility expectedCtorAccessibility = TypeDefinition.IsAbstract ? Accessibility.Protected : Accessibility.Public;
+
 				if (context.Settings.UsePrimaryConstructorSyntaxForNonRecordTypes
 					&& RecordDecompiler == null && constructorsNotChainedWithThis.Count == 1)
 				{
@@ -351,7 +353,8 @@ public bool Analyze(IEnumerable<AstNode> members)
 
 					var initializer = InitializerSequence.Analyze(this, ctor, ctorMethod);
 
-					if (initializer is { CoversFullBody: true, HasDuplicateAssignments: false, Statements.Count: > 0 })
+					if (initializer is { CoversFullBody: true, HasDuplicateAssignments: false, Statements.Count: > 0 }
+						&& ctorMethod.Accessibility == expectedCtorAccessibility)
 					{
 						bool transformToPrimaryConstructor = MetadataTokens.GetRowNumber(ctorMethod.MetadataToken) == firstMethodRowNumber;