[vala/staging: 3/5] codegen: Use array_length_cexpr to support fixed-arrays for return-values

[Rico Tzschichholz <ricotz src gnome org>]

commit a948a3f3b8b3f3f187706b17422f96c410224805
Author: Rico Tzschichholz <ricotz ubuntu com>
Date:   Sat Jul 8 13:15:50 2017 +0200

    codegen: Use array_length_cexpr to support fixed-arrays for return-values
    
    Based on patch by David Lechner
    
    https://bugzilla.gnome.org/show_bug.cgi?id=784691

 codegen/valaccodemethodcallmodule.vala |    2 ++
 tests/Makefile.am                      |    1 +
 tests/gir/array-fixed-length.test      |    2 +-
 tests/methods/bug784691.vala           |   11 +++++++++++
 vala/valagirparser.vala                |   15 ++++++++-------
 5 files changed, 23 insertions(+), 8 deletions(-)
---
diff --git a/codegen/valaccodemethodcallmodule.vala b/codegen/valaccodemethodcallmodule.vala
index 67a54c9..c911b91 100644
--- a/codegen/valaccodemethodcallmodule.vala
+++ b/codegen/valaccodemethodcallmodule.vala
@@ -518,6 +518,8 @@ public class Vala.CCodeMethodCallModule : CCodeAssignmentModule {
                                        out_arg_map.set (get_param_pos (get_ccode_array_length_pos (m) + 0.01 
* dim), new CCodeUnaryExpression (CCodeUnaryOperator.ADDRESS_OF, temp_ref));
 
                                        append_array_length (expr, temp_ref);
+                               } else if (get_ccode_array_length_expr (m) != null) {
+                                       append_array_length (expr, new CCodeConstant 
(get_ccode_array_length_expr (m)));
                                } else {
                                        append_array_length (expr, new CCodeConstant ("-1"));
                                }
diff --git a/tests/Makefile.am b/tests/Makefile.am
index b3e5f7c..7f54332 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -96,6 +96,7 @@ TESTS = \
        methods/bug774060.vala \
        methods/bug775466.test \
        methods/bug781061.vala \
+       methods/bug784691.vala \
        methods/generics.vala \
        methods/printf-invalid.test \
        methods/printf-constructor.vala \
diff --git a/tests/gir/array-fixed-length.test b/tests/gir/array-fixed-length.test
index 0d7e70e..d4ea017 100644
--- a/tests/gir/array-fixed-length.test
+++ b/tests/gir/array-fixed-length.test
@@ -62,7 +62,7 @@ Output:
 public static void change_array ([CCode (array_length = false)] ref uint8 array[2]);
 [CCode (cheader_filename = "test.h")]
 public static void get_array_out ([CCode (array_length = false)] out uint8 array[8]);
-[CCode (array_length = false, cheader_filename = "test.h")]
+[CCode (array_length = false, array_length_cexpr = "16", cheader_filename = "test.h")]
 public static unowned uint8[] get_array_return ();
 [CCode (cheader_filename = "test.h")]
 public static void set_array ([CCode (array_length = false)] uint8 array[4]);
diff --git a/tests/methods/bug784691.vala b/tests/methods/bug784691.vala
new file mode 100644
index 0000000..7f11eee
--- /dev/null
+++ b/tests/methods/bug784691.vala
@@ -0,0 +1,11 @@
+const int[] FOO = { 0, 1, 2 };
+
+[CCode (array_length = false, array_length_cexpr = "3")]
+unowned int[] get_foo () {
+       assert (FOO.length == 3);
+       return FOO;
+}
+
+void main () {
+       assert (get_foo ().length == 3);
+}
diff --git a/vala/valagirparser.vala b/vala/valagirparser.vala
index f030c08..177339a 100644
--- a/vala/valagirparser.vala
+++ b/vala/valagirparser.vala
@@ -2411,13 +2411,6 @@ public class Vala.GirParser : CodeVisitor {
                }
                type = element_get_type (type, true, ref no_array_length, ref array_null_terminated);
 
-               // FIXME No support for fixed-size array as return-value
-               var array_type = type as ArrayType;
-               if (array_type != null && array_type.fixed_length) {
-                       array_type.fixed_length = false;
-                       array_type.length = null;
-               }
-
                end_element ("return-value");
                return type;
        }
@@ -3098,6 +3091,14 @@ public class Vala.GirParser : CodeVisitor {
                s.comment = comment;
                s.external = true;
 
+               // Transform fixed-array properties of return-type into ccode-attribute
+               var array_type = return_type as ArrayType;
+               if (array_type != null && array_type.fixed_length) {
+                       s.set_attribute_string ("CCode", "array_length_cexpr", ((IntegerLiteral) 
array_type.length).value);
+                       array_type.fixed_length = false;
+                       array_type.length = null;
+               }
+
                if (s is Signal) {
                        if (current.girdata["name"] != name.replace ("_", "-")) {
                                s.set_attribute_string ("CCode", "cname", current.girdata["name"]);