new loplugin finalprotected

look for final classes, and make sure they don't have protected members

Change-Id: I1fa810659bba02b61a5160dbfd8e24185ec9abf4
Reviewed-on: https://gerrit.libreoffice.org/30895
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>
Tested-by: Noel Grandin <noel.grandin@collabora.co.uk>

2 files changed, 115 insertions, 0 deletions

diff --git a/compilerplugins/clang/finalprotected.cxx b/compilerplugins/clang/finalprotected.cxx
new file mode 100644
index 000000000000..35e41017a011
--- /dev/null
+++ b/compilerplugins/clang/finalprotected.cxx
@@ -0,0 +1,80 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+#include <string>
+#include <iostream>
+#include <map>
+#include <set>
+
+#include "plugin.hxx"
+#include "clang/AST/CXXInheritance.h"
+
+// Check for final classes that have protected members
+
+namespace
+{
+
+class FinalProtected:
+    public RecursiveASTVisitor<FinalProtected>, public loplugin::Plugin
+{
+public:
+    explicit FinalProtected(InstantiationData const & data): Plugin(data) {}
+
+    virtual void run() override {
+        TraverseDecl(compiler.getASTContext().getTranslationUnitDecl());
+    }
+
+    bool VisitCXXMethodDecl(CXXMethodDecl const *);
+    bool VisitFieldDecl(FieldDecl const *);
+};
+
+
+bool FinalProtected::VisitCXXMethodDecl(CXXMethodDecl const * cxxMethodDecl)
+{
+    if (ignoreLocation(cxxMethodDecl)) {
+        return true;
+    }
+    if (cxxMethodDecl->getAccess() != AS_protected) {
+        return true;
+    }
+    if (!cxxMethodDecl->getParent()->hasAttr<FinalAttr>()) {
+        return true;
+    }
+    cxxMethodDecl = cxxMethodDecl->getCanonicalDecl();
+    report(DiagnosticsEngine::Warning,
+            "final class should not have protected members - convert them to private",
+            cxxMethodDecl->getLocStart())
+        << cxxMethodDecl->getSourceRange();
+    return true;
+}
+
+bool FinalProtected::VisitFieldDecl(FieldDecl const * fieldDecl)
+{
+    if (ignoreLocation(fieldDecl)) {
+        return true;
+    }
+    if (fieldDecl->getAccess() != AS_protected) {
+        return true;
+    }
+    if (!fieldDecl->getParent()->hasAttr<FinalAttr>()) {
+        return true;
+    }
+    fieldDecl = fieldDecl->getCanonicalDecl();
+    report(DiagnosticsEngine::Warning,
+            "final class should not have protected members - convert them to private",
+            fieldDecl->getLocStart())
+        << fieldDecl->getSourceRange();
+    return true;
+}
+
+loplugin::Plugin::Registration< FinalProtected > X("finalprotected", true);
+
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/compilerplugins/clang/test/finalprotected.cxx b/compilerplugins/clang/test/finalprotected.cxx
new file mode 100644
index 000000000000..b1565781af95
--- /dev/null
+++ b/compilerplugins/clang/test/finalprotected.cxx
@@ -0,0 +1,35 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4; fill-column: 100 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+
+class S final {
+protected:
+    void f(int f) { f1 = f; }  // expected-error {{final class should not have protected members - convert them to private [loplugin:finalprotected]}} expected-error {{Unreferenced externally visible function definition [loplugin:unreffun]}}
+    int f1;      // expected-error {{final class should not have protected members - convert them to private [loplugin:finalprotected]}}
+public:
+    void g();    // expected-error {{extern prototype in main file without definition [loplugin:externandnotdefined]}} expected-error {{Unreferenced function declaration [loplugin:unreffun]}}
+    int g1;
+private:
+    void h();    // expected-error {{extern prototype in main file without definition [loplugin:externandnotdefined]}} expected-error {{Unreferenced function declaration [loplugin:unreffun]}}
+    int h1;
+};
+
+class S2 {
+protected:
+    void f(int f) { f1 = f; } // expected-error {{Unreferenced externally visible function definition [loplugin:unreffun]}}
+    int f1;
+public:
+    void g();    // expected-error {{extern prototype in main file without definition [loplugin:externandnotdefined]}} expected-error {{Unreferenced function declaration [loplugin:unreffun]}}
+    int g1;
+private:
+    void h();    // expected-error {{extern prototype in main file without definition [loplugin:externandnotdefined]}} expected-error {{Unreferenced function declaration [loplugin:unreffun]}}
+    int h1;
+};
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab cinoptions=b1,g0,N-s cinkeys+=0=break: */