1 files changed, 110 insertions, 0 deletions
diff --git a/compilerplugins/clang/simplifyconstruct.cxx b/compilerplugins/clang/simplifyconstruct.cxx
new file mode 100644
index 0000000000..d9eff0b3af
--- /dev/null
+++ b/compilerplugins/clang/simplifyconstruct.cxx
@@ -0,0 +1,110 @@
+/* -*- 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/.
+ */
+
+#ifndef LO_CLANG_SHARED_PLUGINS
+
+#include <memory>
+#include <cassert>
+#include <string>
+#include <iostream>
+#include <fstream>
+#include <set>
+#include "plugin.hxx"
+#include "check.hxx"
+
+namespace
+{
+class SimplifyConstruct : public loplugin::FilteringPlugin<SimplifyConstruct>
+{
+public:
+    explicit SimplifyConstruct(loplugin::InstantiationData const& data)
+        : FilteringPlugin(data)
+    {
+    }
+
+    virtual void run() override { TraverseDecl(compiler.getASTContext().getTranslationUnitDecl()); }
+
+    bool VisitCXXConstructExpr(CXXConstructExpr const*);
+    bool VisitVarDecl(VarDecl const*);
+
+    // ignore some contexts within which nullptr is fine
+    bool TraverseReturnStmt(ReturnStmt*) { return true; }
+    bool TraverseInitListExpr(InitListExpr*) { return true; }
+    bool TraverseCXXBindTemporaryExpr(CXXBindTemporaryExpr*) { return true; }
+    // ignore them for the shared visitor too
+    bool PreTraverseReturnStmt(ReturnStmt*) { return false; }
+    bool PreTraverseInitListExpr(InitListExpr*) { return false; }
+    bool PreTraverseCXXBindTemporaryExpr(CXXBindTemporaryExpr*) { return false; }
+};
+
+bool SimplifyConstruct::VisitCXXConstructExpr(CXXConstructExpr const* constructExpr)
+{
+    if (ignoreLocation(constructExpr))
+        return true;
+    auto tc = loplugin::TypeCheck(constructExpr->getType());
+    if (!tc.Class("unique_ptr").StdNamespace() && !tc.Class("shared_ptr").StdNamespace()
+        && !tc.Class("SvRef").Namespace("tools").GlobalNamespace()
+        && !tc.Class("Reference").Namespace("rtl").GlobalNamespace()
+        && !tc.Class("Reference")
+                .Namespace("uno")
+                .Namespace("star")
+                .Namespace("sun")
+                .Namespace("com")
+                .GlobalNamespace())
+        return true;
+    if (constructExpr->getNumArgs() == 1
+        && isa<CXXNullPtrLiteralExpr>(constructExpr->getArg(0)->IgnoreParenImpCasts()))
+    {
+        report(DiagnosticsEngine::Warning,
+               "no need to explicitly init an instance of %0 with nullptr, just use default "
+               "constructor",
+               constructExpr->getSourceRange().getBegin())
+            << constructExpr->getType() << constructExpr->getSourceRange();
+    }
+    return true;
+}
+
+bool SimplifyConstruct::VisitVarDecl(VarDecl const* varDecl)
+{
+    if (ignoreLocation(varDecl))
+        return true;
+    // cannot use OUString s("xxx") style syntax in a parameter
+    if (isa<ParmVarDecl>(varDecl))
+        return true;
+    varDecl = varDecl->getCanonicalDecl();
+    if (!varDecl->getInit())
+        return true;
+    if (varDecl->getInitStyle() != VarDecl::InitializationStyle::CInit)
+        return true;
+    if (!varDecl->getType()->isRecordType())
+        return true;
+    if (isa<AutoType>(varDecl->getType()))
+        return true;
+
+    auto init = varDecl->getInit();
+    auto const e1 = init->IgnoreImplicit();
+    if (!isa<CXXFunctionalCastExpr>(e1) && !isa<CXXTemporaryObjectExpr>(e1))
+        return true;
+
+    // e.g. the LANGUAGE_DONTKNOW defines
+    if (compiler.getSourceManager().isMacroBodyExpansion(init->getBeginLoc()))
+        return true;
+
+    report(DiagnosticsEngine::Warning, "simplify", varDecl->getLocation())
+        << varDecl->getSourceRange();
+
+    return true;
+}
+
+loplugin::Plugin::Registration<SimplifyConstruct> simplifyconstruct("simplifyconstruct", true);
+}
+
+#endif // LO_CLANG_SHARED_PLUGINS
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */