compilerplugins/clang/stringconcatliterals.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 #ifndef LO_CLANG_SHARED_PLUGINS
  11
  12 #include "config_clang.h"
  13
  14 #include "plugin.hxx"
  15 #include "check.hxx"
  16
  17 namespace {
  18
  19 Expr const * stripCtor(Expr const * expr) {
  20     auto e1 = expr;
  21     if (auto const e = dyn_cast<CXXFunctionalCastExpr>(e1)) {
  22         e1 = e->getSubExpr()->IgnoreParenImpCasts();
  23     }
  24     if (auto const e = dyn_cast<CXXBindTemporaryExpr>(e1)) {
  25         e1 = e->getSubExpr()->IgnoreParenImpCasts();
  26     }
  27     auto const e2 = dyn_cast<CXXConstructExpr>(e1);
  28     if (e2 == nullptr) {
  29         return expr;
  30     }
  31     auto qt = loplugin::DeclCheck(e2->getConstructor());
  32     if (qt.MemberFunction().Class("OStringLiteral").Namespace("rtl").GlobalNamespace()
  33         || qt.MemberFunction().Class("OUStringLiteral").Namespace("rtl").GlobalNamespace())
  34     {
  35         if (e2->getNumArgs() == 1) {
  36             return e2->getArg(0)->IgnoreParenImpCasts();
  37         }
  38         return expr;
  39     }
  40     if (!((qt.MemberFunction().Class("OString").Namespace("rtl")
  41            .GlobalNamespace())
  42           || (qt.MemberFunction().Class("OUString").Namespace("rtl")
  43               .GlobalNamespace())))
  44     {
  45         return expr;
  46     }
  47     if (e2->getNumArgs() != 2) {
  48         return expr;
  49     }
  50     return e2->getArg(0)->IgnoreParenImpCasts();
  51 }
  52
  53 class StringConcatLiterals:
  54     public loplugin::FilteringPlugin<StringConcatLiterals>
  55 {
  56 public:
  57     explicit StringConcatLiterals(loplugin::InstantiationData const & data):
  58         FilteringPlugin(data) {}
  59
  60     void run() override
  61     { TraverseDecl(compiler.getASTContext().getTranslationUnitDecl()); }
  62
  63     bool VisitCallExpr(CallExpr const * expr);
  64
  65 private:
  66     bool isStringLiteral(Expr const * expr);
  67 };
  68
  69 bool StringConcatLiterals::VisitCallExpr(CallExpr const * expr) {
  70     if (ignoreLocation(expr)) {
  71         return true;
  72     }
  73     FunctionDecl const * fdecl = expr->getDirectCallee();
  74     if (fdecl == nullptr) {
  75         return true;
  76     }
  77     OverloadedOperatorKind oo = fdecl->getOverloadedOperator();
  78     if ((oo != OverloadedOperatorKind::OO_Plus
  79          && oo != OverloadedOperatorKind::OO_LessLess)
  80         || fdecl->getNumParams() != 2 || expr->getNumArgs() != 2
  81         || !isStringLiteral(expr->getArg(1)->IgnoreParenImpCasts()))
  82     {
  83         return true;
  84     }
  85     SourceLocation leftLoc;
  86     auto const leftExpr = expr->getArg(0)->IgnoreParenImpCasts();
  87     if (isStringLiteral(leftExpr)) {
  88         leftLoc = leftExpr->getBeginLoc();
  89     } else {
  90         CallExpr const * left = dyn_cast<CallExpr>(leftExpr);
  91         if (left == nullptr) {
  92             return true;
  93         }
  94         FunctionDecl const * ldecl = left->getDirectCallee();
  95         if (ldecl == nullptr) {
  96             return true;
  97         }
  98         OverloadedOperatorKind loo = ldecl->getOverloadedOperator();
  99         if ((loo != OverloadedOperatorKind::OO_Plus
 100              && loo != OverloadedOperatorKind::OO_LessLess)
 101             || ldecl->getNumParams() != 2 || left->getNumArgs() != 2
 102             || !isStringLiteral(left->getArg(1)->IgnoreParenImpCasts()))
 103         {
 104             return true;
 105         }
 106         leftLoc = left->getArg(1)->getBeginLoc();
 107     }
 108
 109     // We add an extra " " in the TOOLS_WARN_EXCEPTION macro, which triggers this plugin
 110     if (loplugin::isSamePathname(
 111             getFilenameOfLocation(
 112                 compiler.getSourceManager().getSpellingLoc(
 113                     compiler.getSourceManager().getImmediateMacroCallerLoc(
 114                         compiler.getSourceManager().getImmediateMacroCallerLoc(
 115                             compiler.getSourceManager().getImmediateMacroCallerLoc(
 116                                 expr->getBeginLoc()))))),
 117             SRCDIR "/include/comphelper/diagnose_ex.hxx"))
 118         return true;
 119
 120     StringRef name {
 121         getFilenameOfLocation(
 122             compiler.getSourceManager().getSpellingLoc(expr->getBeginLoc())) };
 123     if (loplugin::isSamePathname(
 124             name, SRCDIR "/sal/qa/rtl/oustringbuffer/test_oustringbuffer_assign.cxx")
 125         || loplugin::isSamePathname(
 126             name, SRCDIR "/sal/qa/rtl/strings/test_ostring_concat.cxx")
 127         || loplugin::isSamePathname(
 128             name, SRCDIR "/sal/qa/rtl/strings/test_oustring_concat.cxx"))
 129     {
 130         return true;
 131     }
 132     CXXOperatorCallExpr const * op = dyn_cast<CXXOperatorCallExpr>(expr);
 133     report(
 134         DiagnosticsEngine::Warning,
 135         "replace '%0' between string literals with juxtaposition",
 136         op == nullptr ? expr->getExprLoc() : op->getOperatorLoc())
 137         << (oo == OverloadedOperatorKind::OO_Plus ? "+" : "<<")
 138         << SourceRange(leftLoc, expr->getArg(1)->getEndLoc());
 139     return true;
 140 }
 141
 142 bool StringConcatLiterals::isStringLiteral(Expr const * expr) {
 143     expr = stripCtor(expr);
 144     if (!isa<clang::StringLiteral>(expr)) {
 145         return false;
 146     }
 147     return true;
 148 }
 149
 150 loplugin::Plugin::Registration<StringConcatLiterals> stringconcatliterals("stringconcatliterals");
 151
 152 } // namespace
 153
 154 #endif // LO_CLANG_SHARED_PLUGINS
 155
 156 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */