From a1867f04214d1cb42aadcb4824e7c02137634af4 Mon Sep 17 00:00:00 2001
From: Ivan Bondarev <ibond84@googlemail.com>
Date: Wed, 27 Dec 2023 12:42:58 +0100
Subject: [PATCH] fix #2829

---
 TestSuite/where20.pas                         | 35 +++++++++++++++++++
 .../TreeConversion/syntax_tree_visitor.cs     | 31 +++++++++++++++-
 2 files changed, 65 insertions(+), 1 deletion(-)
 create mode 100644 TestSuite/where20.pas

diff --git a/TestSuite/where20.pas b/TestSuite/where20.pas
new file mode 100644
index 000000000..9999c6cb0
--- /dev/null
+++ b/TestSuite/where20.pas
@@ -0,0 +1,35 @@
+type
+  c1<T1,T2> = class
+    // Если объявить сначала "where T1" - тоже должно работать
+    where T2: IComparable<T1>;
+    where T1: T2;
+    
+    function f1(o: T1): integer;
+    begin
+      //Ошибка: Неизвестное имя 'CompareTo'
+      Result := o.CompareTo(o);
+    end;
+    
+  end;
+  
+  c2<T1,T2> = class
+    // Если объявить сначала "where T1" - тоже должно работать
+    where T2: IComparable<T1>;
+    where T1: T2;
+    
+    function f1(o: T1): integer;
+    begin
+      //Ошибка: Неизвестное имя 'CompareTo'
+      Result := o.CompareTo(o);
+    end;
+    
+  end;
+  
+  
+begin
+  var a := new c1<string,string>;
+  assert(a.f1('abc') = 0);
+  
+  var b := new c2<string,string>;
+  assert(b.f1('abc') = 0);
+end.
\ No newline at end of file
diff --git a/TreeConverter/TreeConversion/syntax_tree_visitor.cs b/TreeConverter/TreeConversion/syntax_tree_visitor.cs
index f565d439b..e62da2762 100644
--- a/TreeConverter/TreeConversion/syntax_tree_visitor.cs
+++ b/TreeConverter/TreeConversion/syntax_tree_visitor.cs
@@ -4100,7 +4100,18 @@ namespace PascalABCCompiler.TreeConverter
             (ctn.Scope as SymbolTable.InterfaceScope).TopInterfaceScopeArray =
                 interf_scopes.ToArray();
         }
-		
+
+        private void InitInterfaceScope(common_type_node ctn, List<SemanticTree.ITypeNode> interfaces)
+        {
+            List<SymbolTable.Scope> interf_scopes = new List<SymbolTable.Scope>(interfaces.Count);
+            foreach (type_node tnode in interfaces)
+            {
+                interf_scopes.Add(tnode.Scope);
+            }
+            (ctn.Scope as SymbolTable.InterfaceScope).TopInterfaceScopeArray =
+                interf_scopes.ToArray();
+        }
+
         private void visit_function_realizations(SyntaxTree.declarations _decls)
         {
         	foreach (SyntaxTree.declaration sd in _decls.defs)
@@ -12969,6 +12980,16 @@ namespace PascalABCCompiler.TreeConverter
                     ind++;
                 }
             }
+            foreach (common_type_node ctn in used_types)
+            {
+                if (ctn.base_type != null && ctn.base_type.is_generic_parameter && ctn.base_type.ImplementingInterfaces != null && ctn.base_type.ImplementingInterfaces.Count > 0)
+                {
+                    foreach (type_node tn in ctn.ImplementingInterfaces)
+                    {
+                        type_table.AddInterface(ctn, tn, null);
+                    }
+                }
+            }
             context.EndSkipGenericInstanceChecking();
         }
 
@@ -13071,6 +13092,14 @@ namespace PascalABCCompiler.TreeConverter
                                     AddError(get_location(specificators[i]), "STATIC_CLASS_CAN_NOT_BE_USED_AS_PARENT_SPECIFICATOR");
                                 check_cycle_inheritance(param, spec_type);
                                 param.SetBaseType(spec_type);
+                                if (spec_type.is_generic_parameter && spec_type.ImplementingInterfaces.Count > 0)
+                                {
+                                    foreach (type_node tn in spec_type.ImplementingInterfaces)
+                                    {
+                                        used_interfs.Add(tn, tn);
+                                        type_table.AddInterface(param, tn, get_location(specificators[i]));
+                                    }
+                                }
                                 base_is_enum = spec_type == SystemLibrary.SystemLibrary.enum_base_type;
                                 // Чтобы в секции where override метода можно было указать class вместо конкретного типа
                                 // Иначе CLR падает с TypeLoadException