Merge pull request #20632 from zaytsev-victor/Fixed20595

Fixed 'Generate Constructor' refactoring for an abstract class.

src/EditorFeatures/CSharpTest/GenerateFromMembers/GenerateConstructorFromMembers/GenerateConstructorFromMembersTests.cs

@@ -637,7 +637,7 @@ public async Task TestGetter_Only_Auto_Props()
 }",
 @"abstract class Contribution
 {
-    public Contribution(string title, int number)
+    protected Contribution(string title, int number)
     {
         Title = title;
         Number = number;
@@ -899,5 +899,26 @@ public void M()
     public void N() { }
 }");
         }
+
+        [Fact, Trait(Traits.Feature, Traits.Features.CodeActionsGenerateConstructorFromMembers)]
+        [WorkItem(20595, "https://github.com/dotnet/roslyn/issues/20595")]
+        public async Task ProtectedConstructorShouldBeGeneratedForAbstractClass()
+        {
+            await TestInRegularAndScriptAsync(
+@"abstract class C 
+{
+    [|public int Prop { get; set; }|]
+}",
+@"abstract class C 
+{
+    protected C(int prop) 
+    {
+        Prop = prop;
+    } 
+
+    public int Prop { get; set; }
+}",
+options: Option(CodeStyleOptions.QualifyFieldAccess, CodeStyleOptions.TrueWithSuggestionEnforcement));
+        }
     }
 }

src/EditorFeatures/VisualBasicTest/GenerateConstructor/GenerateConstructorTests.vb

@@ -556,7 +556,7 @@ Class Derived
 End Class",
 "MustInherit Class Base
     Private x As Integer
-    Public Sub New(x As Integer)
+    Protected Sub New(x As Integer)
         Me.x = x
     End Sub
 End Class

src/Workspaces/Core/Portable/Shared/Extensions/ICodeDefinitionFactoryExtensions.cs

@@ -83,7 +83,7 @@ internal static partial class ICodeDefinitionFactoryExtensions
 
             var constructor = CodeGenerationSymbolFactory.CreateConstructorSymbol(
                 attributes: default,
-                accessibility: Accessibility.Public,
+                accessibility: containingTypeOpt.IsAbstractClass() ? Accessibility.Protected : Accessibility.Public,
                 modifiers: new DeclarationModifiers(),
                 typeName: typeName,
                 parameters: parameters,