CppEditor: generate valid code via "Convert to Pointer/Stack Variable"

Adding a "= new <TypeName>" after converting a stack variable without
assignment or initializer to pointer.
Also remove the assignment when converting from pointer to stack
variable as this works better with explicit constructors.

Fixes: QTCREATORBUG-23181
Change-Id: I377ec32a1b66cf4b96db14cfcb4b71fb96c80c98
Reviewed-by: David Schulz <david.schulz@qt.io>
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

3 files changed, 74 insertions, 23 deletions

diff --git a/doc/src/editors/creator-code-refactoring.qdoc b/doc/src/editors/creator-code-refactoring.qdoc
index 8120a0543c..f333c92bc4 100644
--- a/doc/src/editors/creator-code-refactoring.qdoc
+++ b/doc/src/editors/creator-code-refactoring.qdoc
@@ -755,7 +755,7 @@
                 as
 
     \code
-    QByteArray foo = "foo";
+    QByteArray foo("foo");
     foo.append("bar");
     \endcode
 
diff --git a/src/plugins/cppeditor/cppquickfix_test.cpp b/src/plugins/cppeditor/cppquickfix_test.cpp
index 63f1290b6a..e75464d2b5 100644
--- a/src/plugins/cppeditor/cppquickfix_test.cpp
+++ b/src/plugins/cppeditor/cppquickfix_test.cpp
@@ -1578,7 +1578,7 @@ void CppEditorPlugin::test_quickfix_data()
              "    f2(&str);\n"
              "}\n")
         << _("void foo() {\n"
-             "    QString *str;\n"
+             "    QString *str = new QString;\n"
              "    if (!str->isEmpty())\n"
              "        str->clear();\n"
              "    f1(*str);\n"
@@ -1612,7 +1612,7 @@ void CppEditorPlugin::test_quickfix_data()
              "        str->clear();\n"
              "}\n")
         << _("void foo() {\n"
-             "    QString str = QLatin1String(\"schnurz\");\n"
+             "    QString str(QLatin1String(\"schnurz\"));\n"
              "    if (!str.isEmpty())\n"
              "        str.clear();\n"
              "}\n");
@@ -1731,7 +1731,7 @@ void CppEditorPlugin::test_quickfix_data()
              "    f1(str);\n"
              "}\n")
         << _("void foo() {\n"
-             "    QString *str;\n"
+             "    QString *str = new QString;\n"
              "    str->clear();\n"
              "    {\n"
              "        QString str;\n"
@@ -1808,6 +1808,45 @@ void CppEditorPlugin::test_quickfix_data()
              "    BAR = *foo;\n"
              "}\n");
 
+    QString testObjAndFunc = "struct Object\n"
+                             "{\n"
+                             "    Object(%1){}\n"
+                             "};\n"
+                             "void func()\n"
+                             "{\n"
+                             "    %2\n"
+                             "}\n";
+
+    QTest::newRow("ConvertToStack1_QTCREATORBUG23181")
+        << CppQuickFixFactoryPtr(new ConvertFromAndToPointer)
+        << _(testObjAndFunc.arg("int").arg("Object *@obj = new Object(0);").toUtf8())
+        << _(testObjAndFunc.arg("int").arg("Object obj(0);").toUtf8());
+
+    QTest::newRow("ConvertToStack2_QTCREATORBUG23181")
+        << CppQuickFixFactoryPtr(new ConvertFromAndToPointer)
+        << _(testObjAndFunc.arg("int").arg("Object *@obj = new Object{0};").toUtf8())
+        << _(testObjAndFunc.arg("int").arg("Object obj{0};").toUtf8());
+
+    QTest::newRow("ConvertToPointer1_QTCREATORBUG23181")
+        << CppQuickFixFactoryPtr(new ConvertFromAndToPointer)
+        << _(testObjAndFunc.arg("").arg("Object @obj;").toUtf8())
+        << _(testObjAndFunc.arg("").arg("Object *obj = new Object;").toUtf8());
+
+    QTest::newRow("ConvertToPointer2_QTCREATORBUG23181")
+        << CppQuickFixFactoryPtr(new ConvertFromAndToPointer)
+        << _(testObjAndFunc.arg("").arg("Object @obj();").toUtf8())
+        << _(testObjAndFunc.arg("").arg("Object *obj = new Object();").toUtf8());
+
+    QTest::newRow("ConvertToPointer3_QTCREATORBUG23181")
+        << CppQuickFixFactoryPtr(new ConvertFromAndToPointer)
+        << _(testObjAndFunc.arg("").arg("Object @obj{};").toUtf8())
+        << _(testObjAndFunc.arg("").arg("Object *obj = new Object{};").toUtf8());
+
+    QTest::newRow("ConvertToPointer4_QTCREATORBUG23181")
+        << CppQuickFixFactoryPtr(new ConvertFromAndToPointer)
+        << _(testObjAndFunc.arg("int").arg("Object @obj(0);").toUtf8())
+        << _(testObjAndFunc.arg("int").arg("Object *obj = new Object(0);").toUtf8());
+
     QTest::newRow("InsertQtPropertyMembers_noTriggerInvalidCode")
         << CppQuickFixFactoryPtr(new InsertQtPropertyMembers)
         << _("class C { @Q_PROPERTY(typeid foo READ foo) };\n")
diff --git a/src/plugins/cppeditor/cppquickfixes.cpp b/src/plugins/cppeditor/cppquickfixes.cpp
index d384322bdd..c3c93f7a5e 100644
--- a/src/plugins/cppeditor/cppquickfixes.cpp
+++ b/src/plugins/cppeditor/cppquickfixes.cpp
@@ -4153,20 +4153,21 @@ private:
 
     void removeNewExpression(ChangeSet &changes, NewExpressionAST *newExprAST) const
     {
-        ExpressionListParenAST *exprlist = newExprAST->new_initializer
-                ? newExprAST->new_initializer->asExpressionListParen()
-                : nullptr;
+        ExpressionListAST *exprlist = nullptr;
+        if (newExprAST->new_initializer) {
+            if (ExpressionListParenAST *ast = newExprAST->new_initializer->asExpressionListParen())
+                exprlist = ast->expression_list;
+            else if (BracedInitializerAST *ast = newExprAST->new_initializer->asBracedInitializer())
+                exprlist = ast->expression_list;
+        }
 
-        if (exprlist && exprlist->expression_list) {
+        if (exprlist) {
             // remove 'new' keyword and type before initializer
             changes.remove(m_file->startOf(newExprAST->new_token),
                            m_file->startOf(newExprAST->new_initializer));
 
-            // remove parenthesis around initializer
-            int pos = m_file->startOf(exprlist->lparen_token);
-            changes.remove(pos, pos + 1);
-            pos = m_file->startOf(exprlist->rparen_token);
-            changes.remove(pos, pos + 1);
+            changes.remove(m_file->endOf(m_declaratorAST->equal_token - 1),
+                           m_file->startOf(m_declaratorAST->equal_token + 1));
         } else {
             // remove the whole new expression
             changes.remove(m_file->endOf(m_identifierAST->firstToken()),
@@ -4272,24 +4273,30 @@ private:
         return overview.prettyName(namedType->name->name);
     }
 
-    void insertNewExpression(ChangeSet &changes, CallAST *callAST) const
+    void insertNewExpression(ChangeSet &changes, ExpressionAST *ast) const
     {
         const QString typeName = typeNameOfDeclaration();
-        if (typeName.isEmpty()) {
-            changes.insert(m_file->startOf(callAST), QLatin1String("new "));
+        if (CallAST *callAST = ast->asCall()) {
+            if (typeName.isEmpty()) {
+                changes.insert(m_file->startOf(callAST), QLatin1String("new "));
+            } else {
+                changes.insert(m_file->startOf(callAST),
+                               QLatin1String("new ") + typeName + QLatin1Char('('));
+                changes.insert(m_file->startOf(callAST->lastToken()), QLatin1String(")"));
+            }
         } else {
-            changes.insert(m_file->startOf(callAST),
-                           QLatin1String("new ") + typeName + QLatin1Char('('));
-            changes.insert(m_file->startOf(callAST->lastToken()), QLatin1String(")"));
+            if (typeName.isEmpty())
+                return;
+            changes.insert(m_file->startOf(ast), QLatin1String(" = new ") + typeName);
         }
     }
 
-    void insertNewExpression(ChangeSet &changes, ExpressionListParenAST *exprListAST) const
+    void insertNewExpression(ChangeSet &changes) const
     {
         const QString typeName = typeNameOfDeclaration();
         if (typeName.isEmpty())
             return;
-        changes.insert(m_file->startOf(exprListAST),
+        changes.insert(m_file->endOf(m_identifierAST->firstToken()),
                        QLatin1String(" = new ") + typeName);
     }
 
@@ -4301,10 +4308,15 @@ private:
                 changes.insert(m_file->startOf(idExprAST), QLatin1String("&"));
             } else if (CallAST *callAST = m_declaratorAST->initializer->asCall()) {
                 insertNewExpression(changes, callAST);
-            } else if (ExpressionListParenAST *exprListAST
-                     = m_declaratorAST->initializer->asExpressionListParen()) {
+            } else if (ExpressionListParenAST *exprListAST = m_declaratorAST->initializer
+                                                                 ->asExpressionListParen()) {
                 insertNewExpression(changes, exprListAST);
+            } else if (BracedInitializerAST *bracedInitializerAST = m_declaratorAST->initializer
+                                                                        ->asBracedInitializer()) {
+                insertNewExpression(changes, bracedInitializerAST);
             }
+        } else {
+            insertNewExpression(changes);
         }
 
         // Fix all occurrences of the identifier in this function.