[vala] Support translated string constants

[Jürg Billeter <juergbi src gnome org>]

commit 7c2fd8a2a9d9503496c96854be95fa7f91ef44a6
Author: Jürg Billeter <j bitron ch>
Date:   Tue Feb 8 20:32:35 2011 +0100

    Support translated string constants
    
    Fixes bug 641543.

 codegen/valaccodebasemodule.vala |   13 ++++++++++++-
 vala/valaconstant.vala           |   15 +++++++++++++++
 vala/valastringliteral.vala      |    4 +++-
 3 files changed, 30 insertions(+), 2 deletions(-)
---
diff --git a/codegen/valaccodebasemodule.vala b/codegen/valaccodebasemodule.vala
index 14258bc..328de67 100644
--- a/codegen/valaccodebasemodule.vala
+++ b/codegen/valaccodebasemodule.vala
@@ -1,6 +1,6 @@
 /* valaccodebasemodule.vala
  *
- * Copyright (C) 2006-2010  Jürg Billeter
+ * Copyright (C) 2006-2011  Jürg Billeter
  * Copyright (C) 2006-2008  Raffaele Sandrini
  *
  * This library is free software; you can redistribute it and/or
@@ -3424,6 +3424,17 @@ public abstract class Vala.CCodeBaseModule : CodeGenerator {
 
 	public override void visit_string_literal (StringLiteral expr) {
 		set_cvalue (expr, new CCodeConstant.string (expr.value.replace ("\n", "\\n")));
+
+		if (expr.translate) {
+			// translated string constant
+
+			var m = (Method) root_symbol.scope.lookup ("GLib").scope.lookup ("_");
+			add_symbol_declaration (cfile, m, m.get_cname ());
+
+			var translate = new CCodeFunctionCall (new CCodeIdentifier ("_"));
+			translate.add_argument (get_cvalue (expr));
+			set_cvalue (expr, translate);
+		}
 	}
 
 	public override void visit_regex_literal (RegexLiteral expr) {
diff --git a/vala/valaconstant.vala b/vala/valaconstant.vala
index fab450c..c9b880c 100644
--- a/vala/valaconstant.vala
+++ b/vala/valaconstant.vala
@@ -203,6 +203,21 @@ public class Vala.Constant : Symbol, Lockable {
 					return false;
 				}
 
+				// support translated string constants for efficiency / convenience
+				// even though the expression is not a compile-time constant
+				var call = value as MethodCall;
+				if (call != null) {
+					var method_type = call.call.value_type as MethodType;
+					if (method_type != null && method_type.method_symbol.get_full_name () == "GLib._") {
+						// first argument is string
+						var literal = call.get_argument_list ().get (0) as StringLiteral;
+						if (literal != null) {
+							value = literal;
+							literal.translate = true;
+						}
+					}
+				}
+
 				if (!value.is_constant ()) {
 					error = true;
 					Report.error (value.source_reference, "Value must be constant");
diff --git a/vala/valastringliteral.vala b/vala/valastringliteral.vala
index 69fc4d7..ffb4285 100644
--- a/vala/valastringliteral.vala
+++ b/vala/valastringliteral.vala
@@ -1,6 +1,6 @@
 /* valastringliteral.vala
  *
- * Copyright (C) 2006-2010  Jürg Billeter
+ * Copyright (C) 2006-2011  Jürg Billeter
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
@@ -31,6 +31,8 @@ public class Vala.StringLiteral : Literal {
 	 */
 	public string value { get; set; }
 
+	public bool translate { get; set; }
+
 	/**
 	 * Creates a new string literal.
 	 *