[vala/staging: 1/3] vala: Accept "unowned var" as type for foreach variable declaration

[Rico Tzschichholz <ricotz src gnome org>]

commit d43edc5a6f17f5c2f515f6e659da83c73ce639fa
Author: Rico Tzschichholz <ricotz ubuntu com>
Date:   Mon Nov 9 17:02:50 2020 +0100

    vala: Accept "unowned var" as type for foreach variable declaration
    
    In addition to 39331e235f1183223c8ea685e3501ab4ca932c8f
    
    See https://gitlab.gnome.org/GNOME/vala/issues/152

 tests/Makefile.am              |  1 +
 tests/parser/foreach.vala      | 11 +++++++++++
 vala/valaforeachstatement.vala | 16 ++++++++++++++--
 vala/valaparser.vala           | 20 ++++++++++++++------
 4 files changed, 40 insertions(+), 8 deletions(-)
---
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 47e9a711b..0c5f059e6 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -745,6 +745,7 @@ TESTS = \
        parser/field-no-override.test \
        parser/field-no-static-class.test \
        parser/field-no-virtual.test \
+       parser/foreach.vala \
        parser/foreach-no-type.test \
        parser/function-syntax-error.test \
        parser/inner-array-size.test \
diff --git a/tests/parser/foreach.vala b/tests/parser/foreach.vala
new file mode 100644
index 000000000..7879b67da
--- /dev/null
+++ b/tests/parser/foreach.vala
@@ -0,0 +1,11 @@
+void main () {
+       string[] array = { "foo", "bar", "manam" };
+       foreach (string s in array) {
+       }
+       foreach (unowned string s in array) {
+       }
+       foreach (var s in array) {
+       }
+       foreach (unowned var s in array) {
+       }
+}
diff --git a/vala/valaforeachstatement.vala b/vala/valaforeachstatement.vala
index 258a81dae..2c81b202a 100644
--- a/vala/valaforeachstatement.vala
+++ b/vala/valaforeachstatement.vala
@@ -155,6 +155,10 @@ public class Vala.ForeachStatement : Block {
 
                checked = true;
 
+               if (type_reference == null) {
+                       type_reference = new VarType ();
+               }
+
                // analyze collection expression first, used for type inference
                if (!collection.check (context)) {
                        // ignore inner error
@@ -330,9 +334,13 @@ public class Vala.ForeachStatement : Block {
 
        bool analyze_element_type (DataType element_type) {
                // analyze element type
-               if (type_reference == null) {
+               if (type_reference is VarType) {
                        // var type
                        type_reference = element_type.copy ();
+                       // FIXME Only follows "unowned var" otherwise inherit ownership of element-type
+                       if (!type_reference.value_owned) {
+                               type_reference.value_owned = false;
+                       }
                } else if (!element_type.compatible (type_reference)) {
                        error = true;
                        Report.error (source_reference, "Foreach: Cannot convert from `%s' to `%s'", 
element_type.to_string (), type_reference.to_string ());
@@ -348,9 +356,13 @@ public class Vala.ForeachStatement : Block {
 
        bool check_without_iterator (CodeContext context, DataType collection_type, DataType element_type) {
                // analyze element type
-               if (type_reference == null) {
+               if (type_reference is VarType) {
                        // var type
                        type_reference = element_type.copy ();
+                       // FIXME Only follows "unowned var" otherwise inherit ownership of element-type
+                       if (!type_reference.value_owned) {
+                               type_reference.value_owned = false;
+                       }
                } else if (!element_type.compatible (type_reference)) {
                        error = true;
                        Report.error (source_reference, "Foreach: Cannot convert from `%s' to `%s'", 
element_type.to_string (), type_reference.to_string ());
diff --git a/vala/valaparser.vala b/vala/valaparser.vala
index fc130c7cb..f54de7832 100644
--- a/vala/valaparser.vala
+++ b/vala/valaparser.vala
@@ -2194,12 +2194,20 @@ public class Vala.Parser : CodeVisitor {
                var begin = get_location ();
                expect (TokenType.FOREACH);
                expect (TokenType.OPEN_PARENS);
-               DataType type = null;
-               if (!accept (TokenType.VAR)) {
-                       type = parse_type (true, true);
-                       if (accept (TokenType.IN)) {
-                               Report.error (type.source_reference, "syntax error, expected var or type");
-                               throw new ParseError.SYNTAX ("expected var or type");
+               var var_or_type = get_location ();
+               DataType type;
+               if (accept (TokenType.UNOWNED) && accept (TokenType.VAR)) {
+                       type = new VarType (false);
+               } else {
+                       rollback (var_or_type);
+                       if (accept (TokenType.VAR)) {
+                               type = new VarType ();
+                       } else {
+                               type = parse_type (true, true);
+                               if (accept (TokenType.IN)) {
+                                       Report.error (type.source_reference, "syntax error, expected `unowned 
var', `var' or type");
+                                       throw new ParseError.SYNTAX ("expected `unowned var', `var' or type");
+                               }
                        }
                }
                string id = parse_identifier ();