[vala] Support postconditions in normal methods

[Jürg Billeter <juergbi src gnome org>]

commit 9a017f8975900a736b231a3b2dee8e0aca8c383f
Author: Jürg Billeter <j bitron ch>
Date:   Thu Jun 4 14:14:09 2009 +0200

    Support postconditions in normal methods
    
    Fixes bug 529680.
---
 codegen/valaccodebasemodule.vala         |   33 +++++++++++++++++++++++++++--
 codegen/valaccodememberaccessmodule.vala |    7 +++++-
 codegen/valaccodemethodmodule.vala       |    8 -------
 vala/valaclass.vala                      |    1 +
 vala/valainterface.vala                  |    2 +-
 vala/valalocalvariable.vala              |    2 +
 vala/valastruct.vala                     |    2 +-
 7 files changed, 41 insertions(+), 14 deletions(-)

diff --git a/codegen/valaccodebasemodule.vala b/codegen/valaccodebasemodule.vala
index 9ce9d08..fa55b8d 100644
--- a/codegen/valaccodebasemodule.vala
+++ b/codegen/valaccodebasemodule.vala
@@ -2343,9 +2343,21 @@ internal class Vala.CCodeBaseModule : CCodeModule {
 		stmt.accept_children (codegen);
 
 		if (stmt.return_expression == null) {
-			stmt.ccodenode = new CCodeReturnStatement ();
-			
-			create_local_free (stmt);
+			var cfrag = new CCodeFragment ();
+
+			// free local variables
+			append_local_free (current_symbol, cfrag);
+
+			if (current_method != null) {
+				// check postconditions
+				foreach (Expression postcondition in current_method.get_postconditions ()) {
+					cfrag.append (create_postcondition_statement (postcondition));
+				}
+			}
+
+			cfrag.append (new CCodeReturnStatement ());
+
+			stmt.ccodenode = cfrag;
 		} else {
 			Symbol return_expression_symbol = null;
 
@@ -2390,6 +2402,13 @@ internal class Vala.CCodeBaseModule : CCodeModule {
 			// free local variables
 			append_local_free (current_symbol, cfrag);
 
+			if (current_method != null) {
+				// check postconditions
+				foreach (Expression postcondition in current_method.get_postconditions ()) {
+					cfrag.append (create_postcondition_statement (postcondition));
+				}
+			}
+
 			// Property getters of non simple structs shall return the struct value as out parameter,
 			// therefore replace any return statement with an assignment statement to the out formal
 			// paramenter and insert an empty return statement afterwards.
@@ -3912,6 +3931,14 @@ internal class Vala.CCodeBaseModule : CCodeModule {
 
 	public override void visit_class (Class cl) {
 	}
+
+	public CCodeStatement create_postcondition_statement (Expression postcondition) {
+		var cassert = new CCodeFunctionCall (new CCodeIdentifier ("g_warn_if_fail"));
+
+		cassert.add_argument ((CCodeExpression) postcondition.ccodenode);
+
+		return new CCodeExpressionStatement (cassert);
+	}
 }
 
 // vim:sw=8 noet
diff --git a/codegen/valaccodememberaccessmodule.vala b/codegen/valaccodememberaccessmodule.vala
index e257ed1..cdeec13 100644
--- a/codegen/valaccodememberaccessmodule.vala
+++ b/codegen/valaccodememberaccessmodule.vala
@@ -298,7 +298,12 @@ internal class Vala.CCodeMemberAccessModule : CCodeControlFlowModule {
 			expr.ccodenode = new CCodeConstant (ev.get_cname ());
 		} else if (expr.symbol_reference is LocalVariable) {
 			var local = (LocalVariable) expr.symbol_reference;
-			expr.ccodenode = get_variable_cexpression (local.name);
+			if (local.is_result) {
+				// used in postconditions
+				expr.ccodenode = new CCodeIdentifier ("result");
+			} else {
+				expr.ccodenode = get_variable_cexpression (local.name);
+			}
 		} else if (expr.symbol_reference is FormalParameter) {
 			var p = (FormalParameter) expr.symbol_reference;
 			if (p.name == "this") {
diff --git a/codegen/valaccodemethodmodule.vala b/codegen/valaccodemethodmodule.vala
index ecf1519..7c1d8c7 100644
--- a/codegen/valaccodemethodmodule.vala
+++ b/codegen/valaccodemethodmodule.vala
@@ -918,14 +918,6 @@ internal class Vala.CCodeMethodModule : CCodeStructModule {
 		return new CCodeExpressionStatement (ccheck);
 	}
 
-	private CCodeStatement create_postcondition_statement (Expression postcondition) {
-		var cassert = new CCodeFunctionCall (new CCodeIdentifier ("g_assert"));
-
-		cassert.add_argument ((CCodeExpression) postcondition.ccodenode);
-
-		return new CCodeExpressionStatement (cassert);
-	}
-
 	private TypeSymbol? find_parent_type (Symbol sym) {
 		while (sym != null) {
 			if (sym is TypeSymbol) {
diff --git a/vala/valaclass.vala b/vala/valaclass.vala
index 2511d1a..7d9a8cd 100644
--- a/vala/valaclass.vala
+++ b/vala/valaclass.vala
@@ -321,6 +321,7 @@ public class Vala.Class : ObjectTypeSymbol {
 				m.scope.remove (m.result_var.name);
 			}
 			m.result_var = new LocalVariable (m.return_type.copy (), "result");
+			m.result_var.is_result = true;
 		}
 		if (m is CreationMethod) {
 			if (m.name == null) {
diff --git a/vala/valainterface.vala b/vala/valainterface.vala
index be55fcf..9966477 100644
--- a/vala/valainterface.vala
+++ b/vala/valainterface.vala
@@ -140,7 +140,7 @@ public class Vala.Interface : ObjectTypeSymbol {
 		}
 		if (!(m.return_type is VoidType) && m.get_postconditions ().size > 0) {
 			m.result_var = new LocalVariable (m.return_type.copy (), "result");
-			m.scope.add (m.result_var.name, m.result_var);
+			m.result_var.is_result = true;
 		}
 
 		methods.add (m);
diff --git a/vala/valalocalvariable.vala b/vala/valalocalvariable.vala
index 7502551..c404b2d 100644
--- a/vala/valalocalvariable.vala
+++ b/vala/valalocalvariable.vala
@@ -54,6 +54,8 @@ public class Vala.LocalVariable : Symbol {
 		}
 	}
 
+	public bool is_result { get; set; }
+
 	/**
 	 * Floating variables may only be accessed exactly once.
 	 */
diff --git a/vala/valastruct.vala b/vala/valastruct.vala
index f715b3b..8f5fbca 100644
--- a/vala/valastruct.vala
+++ b/vala/valastruct.vala
@@ -177,7 +177,7 @@ public class Vala.Struct : TypeSymbol {
 		}
 		if (!(m.return_type is VoidType) && m.get_postconditions ().size > 0) {
 			m.result_var = new LocalVariable (m.return_type.copy (), "result");
-			m.scope.add (m.result_var.name, m.result_var);
+			m.result_var.is_result = true;
 		}
 		if (m is CreationMethod) {
 			if (m.name == null) {