compilerplugins/clang/stringconcat.cxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
   4  *
   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  */
   9
  10 #include "plugin.hxx"
  11
  12 namespace {
  13
  14 class StringConcat:
  15     public RecursiveASTVisitor<StringConcat>, public loplugin::Plugin
  16 {
  17 public:
  18     explicit StringConcat(InstantiationData const & data): Plugin(data) {}
  19
  20     void run() override
  21     { TraverseDecl(compiler.getASTContext().getTranslationUnitDecl()); }
  22
  23     bool VisitCallExpr(CallExpr const * expr);
  24 };
  25
  26 bool StringConcat::VisitCallExpr(CallExpr const * expr) {
  27     if (ignoreLocation(expr)) {
  28         return true;
  29     }
  30     FunctionDecl const * fdecl = expr->getDirectCallee();
  31     if (fdecl == nullptr) {
  32         return true;
  33     }
  34     OverloadedOperatorKind oo = fdecl->getOverloadedOperator();
  35     if ((oo != OverloadedOperatorKind::OO_Plus
  36          && oo != OverloadedOperatorKind::OO_LessLess)
  37         || fdecl->getNumParams() != 2 || expr->getNumArgs() != 2
  38         || !isa<StringLiteral>(expr->getArg(1)->IgnoreParenImpCasts()))
  39     {
  40         return true;
  41     }
  42     CallExpr const * left = dyn_cast<CallExpr>(
  43         expr->getArg(0)->IgnoreParenImpCasts());
  44     if (left == nullptr) {
  45         return true;
  46     }
  47     FunctionDecl const * ldecl = left->getDirectCallee();
  48     if (ldecl == nullptr) {
  49         return true;
  50     }
  51     OverloadedOperatorKind loo = ldecl->getOverloadedOperator();
  52     if ((loo != OverloadedOperatorKind::OO_Plus
  53          && loo != OverloadedOperatorKind::OO_LessLess)
  54         || ldecl->getNumParams() != 2 || left->getNumArgs() != 2
  55         || !isa<StringLiteral>(left->getArg(1)->IgnoreParenImpCasts()))
  56     {
  57         return true;
  58     }
  59     StringRef name {
  60         compiler.getSourceManager().getFilename(
  61             compiler.getSourceManager().getSpellingLoc(expr->getLocStart())) };
  62     if (name == SRCDIR "/sal/qa/rtl/strings/test_ostring_concat.cxx"
  63         || name == SRCDIR "/sal/qa/rtl/strings/test_oustring_concat.cxx")
  64     {
  65         return true;
  66     }
  67     CXXOperatorCallExpr const * op = dyn_cast<CXXOperatorCallExpr>(expr);
  68     report(
  69         DiagnosticsEngine::Warning,
  70         "replace '%0' between string literals with juxtaposition",
  71         op == nullptr ? expr->getExprLoc() : op->getOperatorLoc())
  72         << (oo == OverloadedOperatorKind::OO_Plus ? "+" : "<<")
  73         << SourceRange(
  74             left->getArg(1)->getLocStart(), expr->getArg(1)->getLocEnd());
  75     return true;
  76 }
  77
  78 loplugin::Plugin::Registration<StringConcat> X("stringconcat");
  79
  80 }
  81
  82 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */