[vala/wip/foreach: 1/7] vala: Avoid taking extra reference of foreach collection for index iteration

[Rico Tzschichholz <ricotz src gnome org>]

commit d45eee6e8c233e15383b57f1dd0706f93084ccc2
Author: Rico Tzschichholz <ricotz ubuntu com>
Date:   Mon Nov 9 15:38:38 2020 +0100

    vala: Avoid taking extra reference of foreach collection for index iteration

 vala/valaforeachstatement.vala | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)
---
diff --git a/vala/valaforeachstatement.vala b/vala/valaforeachstatement.vala
index da80b24aa..258a81dae 100644
--- a/vala/valaforeachstatement.vala
+++ b/vala/valaforeachstatement.vala
@@ -205,7 +205,11 @@ public class Vala.ForeachStatement : Block {
                        return false;
                }
 
-               add_statement (new DeclarationStatement (new LocalVariable (null, "_%s_list".printf 
(variable_name), collection, source_reference), source_reference));
+               var list_type = collection_type.copy ();
+               if (collection.symbol_reference is Variable) {
+                       list_type.value_owned = false;
+               }
+               add_statement (new DeclarationStatement (new LocalVariable (list_type, "_%s_list".printf 
(variable_name), collection, source_reference), source_reference));
                add_statement (new DeclarationStatement (new LocalVariable (null, "_%s_size".printf 
(variable_name), new MemberAccess (new MemberAccess.simple ("_%s_list".printf (variable_name), 
source_reference), "size", source_reference), source_reference), source_reference));
                add_statement (new DeclarationStatement (new LocalVariable (null, "_%s_index".printf 
(variable_name), new UnaryExpression (UnaryOperator.MINUS, new IntegerLiteral ("1", source_reference), 
source_reference), source_reference), source_reference));
                var next = new UnaryExpression (UnaryOperator.INCREMENT, new MemberAccess.simple 
("_%s_index".printf (variable_name), source_reference), source_reference);