Fix bug#411 - "Incorrect return statement generated in a function that returns a reference"

Reviewer: Luciano Wolf <luciano.wolf@openbossa.org>
          Marcelo Lira <marcelo.lira@openbossa.org>

6 files changed, 75 insertions, 14 deletions

diff --git a/generator/cppgenerator.cpp b/generator/cppgenerator.cpp
index 79cabeadf..e031f39a3 100644
--- a/generator/cppgenerator.cpp
+++ b/generator/cppgenerator.cpp
@@ -490,14 +490,36 @@ void CppGenerator::writeVirtualMethodNative(QTextStream &s, const AbstractMetaFu
 
     Indentation indentation(INDENT);
 
+    QString defaultReturnExpr;
+    if (func->type()) {
+        foreach (FunctionModification mod, func->modifications()) {
+            foreach (ArgumentModification argMod, mod.argument_mods) {
+                if (argMod.index == 0 && !argMod.replacedDefaultExpression.isEmpty()) {
+                    QRegExp regex("%(\\d+)");
+                    defaultReturnExpr = argMod.replacedDefaultExpression;
+                    int offset = 0;
+                    while ((offset = regex.indexIn(defaultReturnExpr, offset)) != -1) {
+                        int argId = regex.cap(1).toInt() - 1;
+                        if (argId < 0 || argId > func->arguments().count()) {
+                            ReportHandler::warning("The expression used in return value contains an invalid index.");
+                            break;
+                        }
+                        defaultReturnExpr.replace(regex.cap(0), func->arguments()[argId]->name());
+                    }
+                }
+            }
+        }
+        if (defaultReturnExpr.isEmpty()) {
+            QTextStream s(&defaultReturnExpr);
+            writeMinimalConstructorCallArguments(s, func->type());
+        }
+    }
+
     if (func->isAbstract() && func->isModifiedRemoved()) {
         ReportHandler::warning("Pure virtual method \"" + func->ownerClass()->name() + "::" + func->minimalSignature() + "\" must be implement but was completely removed on typesystem.");
         s << INDENT << "return";
-        if (func->type()) {
-            s << ' ';
-            writeMinimalConstructorCallArguments(s, func->type());
-        }
-        s << ';' << endl;
+
+        s << ' ' << defaultReturnExpr << ';' << endl;
         s << '}' << endl << endl;
         return;
     }
@@ -525,7 +547,7 @@ void CppGenerator::writeVirtualMethodNative(QTextStream &s, const AbstractMetaFu
         s << "()' not implemented.\");" << endl;
             s << INDENT << "return ";
             if (func->type()) {
-                writeMinimalConstructorCallArguments(s, func->type());
+                s << defaultReturnExpr;
             }
         } else {
             if (func->allowThread()) {
@@ -630,10 +652,7 @@ void CppGenerator::writeVirtualMethodNative(QTextStream &s, const AbstractMetaFu
         {
             Indentation indent(INDENT);
             s << INDENT << "PyErr_Print();" << endl;
-            s << INDENT << "return ";
-            if (type)
-                writeMinimalConstructorCallArguments(s, func->type());
-            s << ';' << endl;
+            s << INDENT << "return " << defaultReturnExpr << ';' << endl;
         }
         s << INDENT << '}' << endl;
 
@@ -676,9 +695,7 @@ void CppGenerator::writeVirtualMethodNative(QTextStream &s, const AbstractMetaFu
                     s << INDENT << "PyErr_Format(PyExc_TypeError, \"Invalid return value in function %s, expected %s, got %s.\", \""
                     << func->ownerClass()->name() << '.' << func->name() << "\", " << desiredType
                     << ", " PYTHON_RETURN_VAR "->ob_type->tp_name);" << endl;
-                    s << INDENT << "return ";
-                    writeMinimalConstructorCallArguments(s, func->type());
-                    s << ';' << endl;
+                    s << INDENT << "return " << defaultReturnExpr << ';' << endl;
                 }
                 s << INDENT << "}" << endl;
             }
diff --git a/tests/libsample/reference.cpp b/tests/libsample/reference.cpp
index 670395ff6..1456b1898 100644
--- a/tests/libsample/reference.cpp
+++ b/tests/libsample/reference.cpp
@@ -67,3 +67,6 @@ Reference::callAlterReferenceIdVirtual(Reference& r)
     alterReferenceIdVirtual(r);
 }
 
+ObjTypeReference::~ObjTypeReference()
+{
+}
diff --git a/tests/libsample/reference.h b/tests/libsample/reference.h
index 046a1518e..cc9fcc91e 100644
--- a/tests/libsample/reference.h
+++ b/tests/libsample/reference.h
@@ -51,9 +51,20 @@ public:
 
     inline static int multiplier() { return 10; }
 
+    virtual Reference& returnMyFirstArg(Reference& ref) { return ref; }
+    virtual Reference& returnMySecondArg(int a, Reference& ref) { return ref; }
 private:
     int m_objId;
 };
 
+class LIBSAMPLE_API ObjTypeReference
+{
+public:
+    virtual ~ObjTypeReference();
+    virtual ObjTypeReference& returnMyFirstArg(ObjTypeReference& ref) { return ref; }
+    virtual ObjTypeReference& returnMySecondArg(int a, ObjTypeReference& ref) { return ref; }
+    virtual ObjTypeReference& justAPureVirtualFunc(ObjTypeReference& ref) = 0;
+};
+
 #endif // REFERENCE_H
 
diff --git a/tests/samplebinding/CMakeLists.txt b/tests/samplebinding/CMakeLists.txt
index 3767a3a36..a0f68c543 100644
--- a/tests/samplebinding/CMakeLists.txt
+++ b/tests/samplebinding/CMakeLists.txt
@@ -43,6 +43,7 @@ ${CMAKE_CURRENT_BINARY_DIR}/sample/nondefaultctor_wrapper.cpp
 ${CMAKE_CURRENT_BINARY_DIR}/sample/objecttype_wrapper.cpp
 ${CMAKE_CURRENT_BINARY_DIR}/sample/objecttypelayout_wrapper.cpp
 ${CMAKE_CURRENT_BINARY_DIR}/sample/objectview_wrapper.cpp
+${CMAKE_CURRENT_BINARY_DIR}/sample/objtypereference_wrapper.cpp
 ${CMAKE_CURRENT_BINARY_DIR}/sample/oddbooluser_wrapper.cpp
 ${CMAKE_CURRENT_BINARY_DIR}/sample/overload_wrapper.cpp
 ${CMAKE_CURRENT_BINARY_DIR}/sample/pairuser_wrapper.cpp
diff --git a/tests/samplebinding/global.h b/tests/samplebinding/global.h
index 54a9795fa..8fae4ddf4 100644
--- a/tests/samplebinding/global.h
+++ b/tests/samplebinding/global.h
@@ -21,6 +21,7 @@
 #include "nondefaultctor.h"
 #include "objecttype.h"
 #include "objecttypelayout.h"
+#include "objecttypereference.h"
 #include "objectview.h"
 #include "oddbool.h"
 #include "overload.h"
diff --git a/tests/samplebinding/typesystem_sample.xml b/tests/samplebinding/typesystem_sample.xml
index 9d14681a2..2960ec734 100644
--- a/tests/samplebinding/typesystem_sample.xml
+++ b/tests/samplebinding/typesystem_sample.xml
@@ -623,7 +623,35 @@
         -->
     </object-type>
 
-    <value-type name="Reference"/>
+    <value-type name="Reference">
+        <modify-function signature="returnMyFirstArg(Reference&amp;)">
+            <modify-argument index="return">
+                <replace-default-expression with="%1"/>
+            </modify-argument>
+        </modify-function>
+        <modify-function signature="returnMySecondArg(int, Reference&amp;)">
+            <modify-argument index="return">
+                <replace-default-expression with="%2"/>
+            </modify-argument>
+        </modify-function>
+    </value-type>
+    <object-type name="ObjTypeReference">
+        <modify-function signature="returnMyFirstArg(ObjTypeReference&amp;)">
+            <modify-argument index="return">
+                <replace-default-expression with="%1"/>
+            </modify-argument>
+        </modify-function>
+        <modify-function signature="returnMySecondArg(int, ObjTypeReference&amp;)">
+            <modify-argument index="return">
+                <replace-default-expression with="%2"/>
+            </modify-argument>
+        </modify-function>
+        <modify-function signature="justAPureVirtualFunc(ObjTypeReference&amp;)">
+            <modify-argument index="return">
+                <replace-default-expression with="%1"/>
+            </modify-argument>
+        </modify-function>
+    </object-type>
     <value-type name="ImplicitConv">
         <enum-type name="CtorEnum"/>
         <enum-type name="ICOverloadedFuncEnum"/>