improve loplugin simplifyconstruct

to find stuff like
OUString s = OUString("xxx")

Change-Id: Ie7ed074c1ae012734c67a2a89c564c1900a4ab04
Reviewed-on: https://gerrit.libreoffice.org/70697
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

1 files changed, 37 insertions, 0 deletions

diff --git a/compilerplugins/clang/simplifyconstruct.cxx b/compilerplugins/clang/simplifyconstruct.cxx
index 652a980cec6a..c3e28ce7bcda 100644
--- a/compilerplugins/clang/simplifyconstruct.cxx
+++ b/compilerplugins/clang/simplifyconstruct.cxx
@@ -31,6 +31,7 @@ public:
     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; }
@@ -69,6 +70,42 @@ bool SimplifyConstruct::VisitCXXConstructExpr(CXXConstructExpr const* constructE
     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()->IgnoreImplicit();
+    auto functionalCast = dyn_cast<CXXFunctionalCastExpr>(init);
+    if (!functionalCast)
+        return true;
+
+    // e.g. the LANGUAGE_DONTKNOW defines
+    if (compiler.getSourceManager().isMacroBodyExpansion(compat::getBeginLoc(init)))
+        return true;
+
+    //    varDecl->getInit()->IgnoreImplicit()->dump();
+    //    varDecl->getType()->dump();
+    //    varDecl->getType()->getUnqualifiedDesugaredType()->dump();
+
+    report(DiagnosticsEngine::Warning, "simplify", varDecl->getLocation())
+        << varDecl->getSourceRange();
+
+    return true;
+}
+
 loplugin::Plugin::Registration<SimplifyConstruct> simplifyconstruct("simplifyconstruct", true);
 }