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      1 //=- LocalizationChecker.cpp -------------------------------------*- C++ -*-==//
      2 //
      3 //                     The LLVM Compiler Infrastructure
      4 //
      5 // This file is distributed under the University of Illinois Open Source
      6 // License. See LICENSE.TXT for details.
      7 //
      8 //===----------------------------------------------------------------------===//
      9 //
     10 //  This file defines a set of checks for localizability including:
     11 //  1) A checker that warns about uses of non-localized NSStrings passed to
     12 //     UI methods expecting localized strings
     13 //  2) A syntactic checker that warns against the bad practice of
     14 //     not including a comment in NSLocalizedString macros.
     15 //
     16 //===----------------------------------------------------------------------===//
     17 
     18 #include "ClangSACheckers.h"
     19 #include "clang/AST/Attr.h"
     20 #include "clang/AST/Decl.h"
     21 #include "clang/AST/DeclObjC.h"
     22 #include "clang/StaticAnalyzer/Core/BugReporter/BugReporter.h"
     23 #include "clang/StaticAnalyzer/Core/BugReporter/BugType.h"
     24 #include "clang/StaticAnalyzer/Core/Checker.h"
     25 #include "clang/StaticAnalyzer/Core/CheckerManager.h"
     26 #include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h"
     27 #include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
     28 #include "clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h"
     29 #include "clang/Lex/Lexer.h"
     30 #include "clang/AST/RecursiveASTVisitor.h"
     31 #include "clang/AST/StmtVisitor.h"
     32 #include "llvm/Support/Unicode.h"
     33 #include "llvm/ADT/StringSet.h"
     34 
     35 using namespace clang;
     36 using namespace ento;
     37 
     38 namespace {
     39 struct LocalizedState {
     40 private:
     41   enum Kind { NonLocalized, Localized } K;
     42   LocalizedState(Kind InK) : K(InK) {}
     43 
     44 public:
     45   bool isLocalized() const { return K == Localized; }
     46   bool isNonLocalized() const { return K == NonLocalized; }
     47 
     48   static LocalizedState getLocalized() { return LocalizedState(Localized); }
     49   static LocalizedState getNonLocalized() {
     50     return LocalizedState(NonLocalized);
     51   }
     52 
     53   // Overload the == operator
     54   bool operator==(const LocalizedState &X) const { return K == X.K; }
     55 
     56   // LLVMs equivalent of a hash function
     57   void Profile(llvm::FoldingSetNodeID &ID) const { ID.AddInteger(K); }
     58 };
     59 
     60 class NonLocalizedStringChecker
     61     : public Checker<check::PostCall, check::PreObjCMessage,
     62                      check::PostObjCMessage,
     63                      check::PostStmt<ObjCStringLiteral>> {
     64 
     65   mutable std::unique_ptr<BugType> BT;
     66 
     67   // Methods that require a localized string
     68   mutable llvm::DenseMap<const IdentifierInfo *,
     69                          llvm::DenseMap<Selector, uint8_t>> UIMethods;
     70   // Methods that return a localized string
     71   mutable llvm::SmallSet<std::pair<const IdentifierInfo *, Selector>, 12> LSM;
     72   // C Functions that return a localized string
     73   mutable llvm::SmallSet<const IdentifierInfo *, 5> LSF;
     74 
     75   void initUIMethods(ASTContext &Ctx) const;
     76   void initLocStringsMethods(ASTContext &Ctx) const;
     77 
     78   bool hasNonLocalizedState(SVal S, CheckerContext &C) const;
     79   bool hasLocalizedState(SVal S, CheckerContext &C) const;
     80   void setNonLocalizedState(SVal S, CheckerContext &C) const;
     81   void setLocalizedState(SVal S, CheckerContext &C) const;
     82 
     83   bool isAnnotatedAsLocalized(const Decl *D) const;
     84   void reportLocalizationError(SVal S, const ObjCMethodCall &M,
     85                                CheckerContext &C, int argumentNumber = 0) const;
     86 
     87   int getLocalizedArgumentForSelector(const IdentifierInfo *Receiver,
     88                                       Selector S) const;
     89 
     90 public:
     91   NonLocalizedStringChecker();
     92 
     93   // When this parameter is set to true, the checker assumes all
     94   // methods that return NSStrings are unlocalized. Thus, more false
     95   // positives will be reported.
     96   DefaultBool IsAggressive;
     97 
     98   void checkPreObjCMessage(const ObjCMethodCall &msg, CheckerContext &C) const;
     99   void checkPostObjCMessage(const ObjCMethodCall &msg, CheckerContext &C) const;
    100   void checkPostStmt(const ObjCStringLiteral *SL, CheckerContext &C) const;
    101   void checkPostCall(const CallEvent &Call, CheckerContext &C) const;
    102 };
    103 
    104 } // end anonymous namespace
    105 
    106 REGISTER_MAP_WITH_PROGRAMSTATE(LocalizedMemMap, const MemRegion *,
    107                                LocalizedState)
    108 
    109 NonLocalizedStringChecker::NonLocalizedStringChecker() {
    110   BT.reset(new BugType(this, "Unlocalizable string",
    111                        "Localizability Issue (Apple)"));
    112 }
    113 
    114 namespace {
    115 class NonLocalizedStringBRVisitor final
    116     : public BugReporterVisitorImpl<NonLocalizedStringBRVisitor> {
    117 
    118   const MemRegion *NonLocalizedString;
    119   bool Satisfied;
    120 
    121 public:
    122   NonLocalizedStringBRVisitor(const MemRegion *NonLocalizedString)
    123       : NonLocalizedString(NonLocalizedString), Satisfied(false) {
    124         assert(NonLocalizedString);
    125   }
    126 
    127   PathDiagnosticPiece *VisitNode(const ExplodedNode *Succ,
    128                                  const ExplodedNode *Pred,
    129                                  BugReporterContext &BRC,
    130                                  BugReport &BR) override;
    131 
    132   void Profile(llvm::FoldingSetNodeID &ID) const override {
    133     ID.Add(NonLocalizedString);
    134   }
    135 };
    136 } // End anonymous namespace.
    137 
    138 #define NEW_RECEIVER(receiver)                                                 \
    139   llvm::DenseMap<Selector, uint8_t> &receiver##M =                             \
    140       UIMethods.insert({&Ctx.Idents.get(#receiver),                            \
    141                         llvm::DenseMap<Selector, uint8_t>()})                  \
    142           .first->second;
    143 #define ADD_NULLARY_METHOD(receiver, method, argument)                         \
    144   receiver##M.insert(                                                          \
    145       {Ctx.Selectors.getNullarySelector(&Ctx.Idents.get(#method)), argument});
    146 #define ADD_UNARY_METHOD(receiver, method, argument)                           \
    147   receiver##M.insert(                                                          \
    148       {Ctx.Selectors.getUnarySelector(&Ctx.Idents.get(#method)), argument});
    149 #define ADD_METHOD(receiver, method_list, count, argument)                     \
    150   receiver##M.insert({Ctx.Selectors.getSelector(count, method_list), argument});
    151 
    152 /// Initializes a list of methods that require a localized string
    153 /// Format: {"ClassName", {{"selectorName:", LocStringArg#}, ...}, ...}
    154 void NonLocalizedStringChecker::initUIMethods(ASTContext &Ctx) const {
    155   if (!UIMethods.empty())
    156     return;
    157 
    158   // UI Methods
    159   NEW_RECEIVER(UISearchDisplayController)
    160   ADD_UNARY_METHOD(UISearchDisplayController, setSearchResultsTitle, 0)
    161 
    162   NEW_RECEIVER(UITabBarItem)
    163   IdentifierInfo *initWithTitleUITabBarItemTag[] = {
    164       &Ctx.Idents.get("initWithTitle"), &Ctx.Idents.get("image"),
    165       &Ctx.Idents.get("tag")};
    166   ADD_METHOD(UITabBarItem, initWithTitleUITabBarItemTag, 3, 0)
    167   IdentifierInfo *initWithTitleUITabBarItemImage[] = {
    168       &Ctx.Idents.get("initWithTitle"), &Ctx.Idents.get("image"),
    169       &Ctx.Idents.get("selectedImage")};
    170   ADD_METHOD(UITabBarItem, initWithTitleUITabBarItemImage, 3, 0)
    171 
    172   NEW_RECEIVER(NSDockTile)
    173   ADD_UNARY_METHOD(NSDockTile, setBadgeLabel, 0)
    174 
    175   NEW_RECEIVER(NSStatusItem)
    176   ADD_UNARY_METHOD(NSStatusItem, setTitle, 0)
    177   ADD_UNARY_METHOD(NSStatusItem, setToolTip, 0)
    178 
    179   NEW_RECEIVER(UITableViewRowAction)
    180   IdentifierInfo *rowActionWithStyleUITableViewRowAction[] = {
    181       &Ctx.Idents.get("rowActionWithStyle"), &Ctx.Idents.get("title"),
    182       &Ctx.Idents.get("handler")};
    183   ADD_METHOD(UITableViewRowAction, rowActionWithStyleUITableViewRowAction, 3, 1)
    184   ADD_UNARY_METHOD(UITableViewRowAction, setTitle, 0)
    185 
    186   NEW_RECEIVER(NSBox)
    187   ADD_UNARY_METHOD(NSBox, setTitle, 0)
    188 
    189   NEW_RECEIVER(NSButton)
    190   ADD_UNARY_METHOD(NSButton, setTitle, 0)
    191   ADD_UNARY_METHOD(NSButton, setAlternateTitle, 0)
    192 
    193   NEW_RECEIVER(NSSavePanel)
    194   ADD_UNARY_METHOD(NSSavePanel, setPrompt, 0)
    195   ADD_UNARY_METHOD(NSSavePanel, setTitle, 0)
    196   ADD_UNARY_METHOD(NSSavePanel, setNameFieldLabel, 0)
    197   ADD_UNARY_METHOD(NSSavePanel, setNameFieldStringValue, 0)
    198   ADD_UNARY_METHOD(NSSavePanel, setMessage, 0)
    199 
    200   NEW_RECEIVER(UIPrintInfo)
    201   ADD_UNARY_METHOD(UIPrintInfo, setJobName, 0)
    202 
    203   NEW_RECEIVER(NSTabViewItem)
    204   ADD_UNARY_METHOD(NSTabViewItem, setLabel, 0)
    205   ADD_UNARY_METHOD(NSTabViewItem, setToolTip, 0)
    206 
    207   NEW_RECEIVER(NSBrowser)
    208   IdentifierInfo *setTitleNSBrowser[] = {&Ctx.Idents.get("setTitle"),
    209                                          &Ctx.Idents.get("ofColumn")};
    210   ADD_METHOD(NSBrowser, setTitleNSBrowser, 2, 0)
    211 
    212   NEW_RECEIVER(UIAccessibilityElement)
    213   ADD_UNARY_METHOD(UIAccessibilityElement, setAccessibilityLabel, 0)
    214   ADD_UNARY_METHOD(UIAccessibilityElement, setAccessibilityHint, 0)
    215   ADD_UNARY_METHOD(UIAccessibilityElement, setAccessibilityValue, 0)
    216 
    217   NEW_RECEIVER(UIAlertAction)
    218   IdentifierInfo *actionWithTitleUIAlertAction[] = {
    219       &Ctx.Idents.get("actionWithTitle"), &Ctx.Idents.get("style"),
    220       &Ctx.Idents.get("handler")};
    221   ADD_METHOD(UIAlertAction, actionWithTitleUIAlertAction, 3, 0)
    222 
    223   NEW_RECEIVER(NSPopUpButton)
    224   ADD_UNARY_METHOD(NSPopUpButton, addItemWithTitle, 0)
    225   IdentifierInfo *insertItemWithTitleNSPopUpButton[] = {
    226       &Ctx.Idents.get("insertItemWithTitle"), &Ctx.Idents.get("atIndex")};
    227   ADD_METHOD(NSPopUpButton, insertItemWithTitleNSPopUpButton, 2, 0)
    228   ADD_UNARY_METHOD(NSPopUpButton, removeItemWithTitle, 0)
    229   ADD_UNARY_METHOD(NSPopUpButton, selectItemWithTitle, 0)
    230   ADD_UNARY_METHOD(NSPopUpButton, setTitle, 0)
    231 
    232   NEW_RECEIVER(NSTableViewRowAction)
    233   IdentifierInfo *rowActionWithStyleNSTableViewRowAction[] = {
    234       &Ctx.Idents.get("rowActionWithStyle"), &Ctx.Idents.get("title"),
    235       &Ctx.Idents.get("handler")};
    236   ADD_METHOD(NSTableViewRowAction, rowActionWithStyleNSTableViewRowAction, 3, 1)
    237   ADD_UNARY_METHOD(NSTableViewRowAction, setTitle, 0)
    238 
    239   NEW_RECEIVER(NSImage)
    240   ADD_UNARY_METHOD(NSImage, setAccessibilityDescription, 0)
    241 
    242   NEW_RECEIVER(NSUserActivity)
    243   ADD_UNARY_METHOD(NSUserActivity, setTitle, 0)
    244 
    245   NEW_RECEIVER(NSPathControlItem)
    246   ADD_UNARY_METHOD(NSPathControlItem, setTitle, 0)
    247 
    248   NEW_RECEIVER(NSCell)
    249   ADD_UNARY_METHOD(NSCell, initTextCell, 0)
    250   ADD_UNARY_METHOD(NSCell, setTitle, 0)
    251   ADD_UNARY_METHOD(NSCell, setStringValue, 0)
    252 
    253   NEW_RECEIVER(NSPathControl)
    254   ADD_UNARY_METHOD(NSPathControl, setPlaceholderString, 0)
    255 
    256   NEW_RECEIVER(UIAccessibility)
    257   ADD_UNARY_METHOD(UIAccessibility, setAccessibilityLabel, 0)
    258   ADD_UNARY_METHOD(UIAccessibility, setAccessibilityHint, 0)
    259   ADD_UNARY_METHOD(UIAccessibility, setAccessibilityValue, 0)
    260 
    261   NEW_RECEIVER(NSTableColumn)
    262   ADD_UNARY_METHOD(NSTableColumn, setTitle, 0)
    263   ADD_UNARY_METHOD(NSTableColumn, setHeaderToolTip, 0)
    264 
    265   NEW_RECEIVER(NSSegmentedControl)
    266   IdentifierInfo *setLabelNSSegmentedControl[] = {
    267       &Ctx.Idents.get("setLabel"), &Ctx.Idents.get("forSegment")};
    268   ADD_METHOD(NSSegmentedControl, setLabelNSSegmentedControl, 2, 0)
    269 
    270   NEW_RECEIVER(NSButtonCell)
    271   ADD_UNARY_METHOD(NSButtonCell, setTitle, 0)
    272   ADD_UNARY_METHOD(NSButtonCell, setAlternateTitle, 0)
    273 
    274   NEW_RECEIVER(NSSliderCell)
    275   ADD_UNARY_METHOD(NSSliderCell, setTitle, 0)
    276 
    277   NEW_RECEIVER(NSControl)
    278   ADD_UNARY_METHOD(NSControl, setStringValue, 0)
    279 
    280   NEW_RECEIVER(NSAccessibility)
    281   ADD_UNARY_METHOD(NSAccessibility, setAccessibilityValueDescription, 0)
    282   ADD_UNARY_METHOD(NSAccessibility, setAccessibilityLabel, 0)
    283   ADD_UNARY_METHOD(NSAccessibility, setAccessibilityTitle, 0)
    284   ADD_UNARY_METHOD(NSAccessibility, setAccessibilityPlaceholderValue, 0)
    285   ADD_UNARY_METHOD(NSAccessibility, setAccessibilityHelp, 0)
    286 
    287   NEW_RECEIVER(NSMatrix)
    288   IdentifierInfo *setToolTipNSMatrix[] = {&Ctx.Idents.get("setToolTip"),
    289                                           &Ctx.Idents.get("forCell")};
    290   ADD_METHOD(NSMatrix, setToolTipNSMatrix, 2, 0)
    291 
    292   NEW_RECEIVER(NSPrintPanel)
    293   ADD_UNARY_METHOD(NSPrintPanel, setDefaultButtonTitle, 0)
    294 
    295   NEW_RECEIVER(UILocalNotification)
    296   ADD_UNARY_METHOD(UILocalNotification, setAlertBody, 0)
    297   ADD_UNARY_METHOD(UILocalNotification, setAlertAction, 0)
    298   ADD_UNARY_METHOD(UILocalNotification, setAlertTitle, 0)
    299 
    300   NEW_RECEIVER(NSSlider)
    301   ADD_UNARY_METHOD(NSSlider, setTitle, 0)
    302 
    303   NEW_RECEIVER(UIMenuItem)
    304   IdentifierInfo *initWithTitleUIMenuItem[] = {&Ctx.Idents.get("initWithTitle"),
    305                                                &Ctx.Idents.get("action")};
    306   ADD_METHOD(UIMenuItem, initWithTitleUIMenuItem, 2, 0)
    307   ADD_UNARY_METHOD(UIMenuItem, setTitle, 0)
    308 
    309   NEW_RECEIVER(UIAlertController)
    310   IdentifierInfo *alertControllerWithTitleUIAlertController[] = {
    311       &Ctx.Idents.get("alertControllerWithTitle"), &Ctx.Idents.get("message"),
    312       &Ctx.Idents.get("preferredStyle")};
    313   ADD_METHOD(UIAlertController, alertControllerWithTitleUIAlertController, 3, 1)
    314   ADD_UNARY_METHOD(UIAlertController, setTitle, 0)
    315   ADD_UNARY_METHOD(UIAlertController, setMessage, 0)
    316 
    317   NEW_RECEIVER(UIApplicationShortcutItem)
    318   IdentifierInfo *initWithTypeUIApplicationShortcutItemIcon[] = {
    319       &Ctx.Idents.get("initWithType"), &Ctx.Idents.get("localizedTitle"),
    320       &Ctx.Idents.get("localizedSubtitle"), &Ctx.Idents.get("icon"),
    321       &Ctx.Idents.get("userInfo")};
    322   ADD_METHOD(UIApplicationShortcutItem,
    323              initWithTypeUIApplicationShortcutItemIcon, 5, 1)
    324   IdentifierInfo *initWithTypeUIApplicationShortcutItem[] = {
    325       &Ctx.Idents.get("initWithType"), &Ctx.Idents.get("localizedTitle")};
    326   ADD_METHOD(UIApplicationShortcutItem, initWithTypeUIApplicationShortcutItem,
    327              2, 1)
    328 
    329   NEW_RECEIVER(UIActionSheet)
    330   IdentifierInfo *initWithTitleUIActionSheet[] = {
    331       &Ctx.Idents.get("initWithTitle"), &Ctx.Idents.get("delegate"),
    332       &Ctx.Idents.get("cancelButtonTitle"),
    333       &Ctx.Idents.get("destructiveButtonTitle"),
    334       &Ctx.Idents.get("otherButtonTitles")};
    335   ADD_METHOD(UIActionSheet, initWithTitleUIActionSheet, 5, 0)
    336   ADD_UNARY_METHOD(UIActionSheet, addButtonWithTitle, 0)
    337   ADD_UNARY_METHOD(UIActionSheet, setTitle, 0)
    338 
    339   NEW_RECEIVER(NSURLSessionTask)
    340   ADD_UNARY_METHOD(NSURLSessionTask, setTaskDescription, 0)
    341 
    342   NEW_RECEIVER(UIAccessibilityCustomAction)
    343   IdentifierInfo *initWithNameUIAccessibilityCustomAction[] = {
    344       &Ctx.Idents.get("initWithName"), &Ctx.Idents.get("target"),
    345       &Ctx.Idents.get("selector")};
    346   ADD_METHOD(UIAccessibilityCustomAction,
    347              initWithNameUIAccessibilityCustomAction, 3, 0)
    348   ADD_UNARY_METHOD(UIAccessibilityCustomAction, setName, 0)
    349 
    350   NEW_RECEIVER(UISearchBar)
    351   ADD_UNARY_METHOD(UISearchBar, setText, 0)
    352   ADD_UNARY_METHOD(UISearchBar, setPrompt, 0)
    353   ADD_UNARY_METHOD(UISearchBar, setPlaceholder, 0)
    354 
    355   NEW_RECEIVER(UIBarItem)
    356   ADD_UNARY_METHOD(UIBarItem, setTitle, 0)
    357 
    358   NEW_RECEIVER(UITextView)
    359   ADD_UNARY_METHOD(UITextView, setText, 0)
    360 
    361   NEW_RECEIVER(NSView)
    362   ADD_UNARY_METHOD(NSView, setToolTip, 0)
    363 
    364   NEW_RECEIVER(NSTextField)
    365   ADD_UNARY_METHOD(NSTextField, setPlaceholderString, 0)
    366 
    367   NEW_RECEIVER(NSAttributedString)
    368   ADD_UNARY_METHOD(NSAttributedString, initWithString, 0)
    369   IdentifierInfo *initWithStringNSAttributedString[] = {
    370       &Ctx.Idents.get("initWithString"), &Ctx.Idents.get("attributes")};
    371   ADD_METHOD(NSAttributedString, initWithStringNSAttributedString, 2, 0)
    372 
    373   NEW_RECEIVER(NSText)
    374   ADD_UNARY_METHOD(NSText, setString, 0)
    375 
    376   NEW_RECEIVER(UIKeyCommand)
    377   IdentifierInfo *keyCommandWithInputUIKeyCommand[] = {
    378       &Ctx.Idents.get("keyCommandWithInput"), &Ctx.Idents.get("modifierFlags"),
    379       &Ctx.Idents.get("action"), &Ctx.Idents.get("discoverabilityTitle")};
    380   ADD_METHOD(UIKeyCommand, keyCommandWithInputUIKeyCommand, 4, 3)
    381   ADD_UNARY_METHOD(UIKeyCommand, setDiscoverabilityTitle, 0)
    382 
    383   NEW_RECEIVER(UILabel)
    384   ADD_UNARY_METHOD(UILabel, setText, 0)
    385 
    386   NEW_RECEIVER(NSAlert)
    387   IdentifierInfo *alertWithMessageTextNSAlert[] = {
    388       &Ctx.Idents.get("alertWithMessageText"), &Ctx.Idents.get("defaultButton"),
    389       &Ctx.Idents.get("alternateButton"), &Ctx.Idents.get("otherButton"),
    390       &Ctx.Idents.get("informativeTextWithFormat")};
    391   ADD_METHOD(NSAlert, alertWithMessageTextNSAlert, 5, 0)
    392   ADD_UNARY_METHOD(NSAlert, addButtonWithTitle, 0)
    393   ADD_UNARY_METHOD(NSAlert, setMessageText, 0)
    394   ADD_UNARY_METHOD(NSAlert, setInformativeText, 0)
    395   ADD_UNARY_METHOD(NSAlert, setHelpAnchor, 0)
    396 
    397   NEW_RECEIVER(UIMutableApplicationShortcutItem)
    398   ADD_UNARY_METHOD(UIMutableApplicationShortcutItem, setLocalizedTitle, 0)
    399   ADD_UNARY_METHOD(UIMutableApplicationShortcutItem, setLocalizedSubtitle, 0)
    400 
    401   NEW_RECEIVER(UIButton)
    402   IdentifierInfo *setTitleUIButton[] = {&Ctx.Idents.get("setTitle"),
    403                                         &Ctx.Idents.get("forState")};
    404   ADD_METHOD(UIButton, setTitleUIButton, 2, 0)
    405 
    406   NEW_RECEIVER(NSWindow)
    407   ADD_UNARY_METHOD(NSWindow, setTitle, 0)
    408   IdentifierInfo *minFrameWidthWithTitleNSWindow[] = {
    409       &Ctx.Idents.get("minFrameWidthWithTitle"), &Ctx.Idents.get("styleMask")};
    410   ADD_METHOD(NSWindow, minFrameWidthWithTitleNSWindow, 2, 0)
    411   ADD_UNARY_METHOD(NSWindow, setMiniwindowTitle, 0)
    412 
    413   NEW_RECEIVER(NSPathCell)
    414   ADD_UNARY_METHOD(NSPathCell, setPlaceholderString, 0)
    415 
    416   NEW_RECEIVER(UIDocumentMenuViewController)
    417   IdentifierInfo *addOptionWithTitleUIDocumentMenuViewController[] = {
    418       &Ctx.Idents.get("addOptionWithTitle"), &Ctx.Idents.get("image"),
    419       &Ctx.Idents.get("order"), &Ctx.Idents.get("handler")};
    420   ADD_METHOD(UIDocumentMenuViewController,
    421              addOptionWithTitleUIDocumentMenuViewController, 4, 0)
    422 
    423   NEW_RECEIVER(UINavigationItem)
    424   ADD_UNARY_METHOD(UINavigationItem, initWithTitle, 0)
    425   ADD_UNARY_METHOD(UINavigationItem, setTitle, 0)
    426   ADD_UNARY_METHOD(UINavigationItem, setPrompt, 0)
    427 
    428   NEW_RECEIVER(UIAlertView)
    429   IdentifierInfo *initWithTitleUIAlertView[] = {
    430       &Ctx.Idents.get("initWithTitle"), &Ctx.Idents.get("message"),
    431       &Ctx.Idents.get("delegate"), &Ctx.Idents.get("cancelButtonTitle"),
    432       &Ctx.Idents.get("otherButtonTitles")};
    433   ADD_METHOD(UIAlertView, initWithTitleUIAlertView, 5, 0)
    434   ADD_UNARY_METHOD(UIAlertView, addButtonWithTitle, 0)
    435   ADD_UNARY_METHOD(UIAlertView, setTitle, 0)
    436   ADD_UNARY_METHOD(UIAlertView, setMessage, 0)
    437 
    438   NEW_RECEIVER(NSFormCell)
    439   ADD_UNARY_METHOD(NSFormCell, initTextCell, 0)
    440   ADD_UNARY_METHOD(NSFormCell, setTitle, 0)
    441   ADD_UNARY_METHOD(NSFormCell, setPlaceholderString, 0)
    442 
    443   NEW_RECEIVER(NSUserNotification)
    444   ADD_UNARY_METHOD(NSUserNotification, setTitle, 0)
    445   ADD_UNARY_METHOD(NSUserNotification, setSubtitle, 0)
    446   ADD_UNARY_METHOD(NSUserNotification, setInformativeText, 0)
    447   ADD_UNARY_METHOD(NSUserNotification, setActionButtonTitle, 0)
    448   ADD_UNARY_METHOD(NSUserNotification, setOtherButtonTitle, 0)
    449   ADD_UNARY_METHOD(NSUserNotification, setResponsePlaceholder, 0)
    450 
    451   NEW_RECEIVER(NSToolbarItem)
    452   ADD_UNARY_METHOD(NSToolbarItem, setLabel, 0)
    453   ADD_UNARY_METHOD(NSToolbarItem, setPaletteLabel, 0)
    454   ADD_UNARY_METHOD(NSToolbarItem, setToolTip, 0)
    455 
    456   NEW_RECEIVER(NSProgress)
    457   ADD_UNARY_METHOD(NSProgress, setLocalizedDescription, 0)
    458   ADD_UNARY_METHOD(NSProgress, setLocalizedAdditionalDescription, 0)
    459 
    460   NEW_RECEIVER(NSSegmentedCell)
    461   IdentifierInfo *setLabelNSSegmentedCell[] = {&Ctx.Idents.get("setLabel"),
    462                                                &Ctx.Idents.get("forSegment")};
    463   ADD_METHOD(NSSegmentedCell, setLabelNSSegmentedCell, 2, 0)
    464   IdentifierInfo *setToolTipNSSegmentedCell[] = {&Ctx.Idents.get("setToolTip"),
    465                                                  &Ctx.Idents.get("forSegment")};
    466   ADD_METHOD(NSSegmentedCell, setToolTipNSSegmentedCell, 2, 0)
    467 
    468   NEW_RECEIVER(NSUndoManager)
    469   ADD_UNARY_METHOD(NSUndoManager, setActionName, 0)
    470   ADD_UNARY_METHOD(NSUndoManager, undoMenuTitleForUndoActionName, 0)
    471   ADD_UNARY_METHOD(NSUndoManager, redoMenuTitleForUndoActionName, 0)
    472 
    473   NEW_RECEIVER(NSMenuItem)
    474   IdentifierInfo *initWithTitleNSMenuItem[] = {
    475       &Ctx.Idents.get("initWithTitle"), &Ctx.Idents.get("action"),
    476       &Ctx.Idents.get("keyEquivalent")};
    477   ADD_METHOD(NSMenuItem, initWithTitleNSMenuItem, 3, 0)
    478   ADD_UNARY_METHOD(NSMenuItem, setTitle, 0)
    479   ADD_UNARY_METHOD(NSMenuItem, setToolTip, 0)
    480 
    481   NEW_RECEIVER(NSPopUpButtonCell)
    482   IdentifierInfo *initTextCellNSPopUpButtonCell[] = {
    483       &Ctx.Idents.get("initTextCell"), &Ctx.Idents.get("pullsDown")};
    484   ADD_METHOD(NSPopUpButtonCell, initTextCellNSPopUpButtonCell, 2, 0)
    485   ADD_UNARY_METHOD(NSPopUpButtonCell, addItemWithTitle, 0)
    486   IdentifierInfo *insertItemWithTitleNSPopUpButtonCell[] = {
    487       &Ctx.Idents.get("insertItemWithTitle"), &Ctx.Idents.get("atIndex")};
    488   ADD_METHOD(NSPopUpButtonCell, insertItemWithTitleNSPopUpButtonCell, 2, 0)
    489   ADD_UNARY_METHOD(NSPopUpButtonCell, removeItemWithTitle, 0)
    490   ADD_UNARY_METHOD(NSPopUpButtonCell, selectItemWithTitle, 0)
    491   ADD_UNARY_METHOD(NSPopUpButtonCell, setTitle, 0)
    492 
    493   NEW_RECEIVER(NSViewController)
    494   ADD_UNARY_METHOD(NSViewController, setTitle, 0)
    495 
    496   NEW_RECEIVER(NSMenu)
    497   ADD_UNARY_METHOD(NSMenu, initWithTitle, 0)
    498   IdentifierInfo *insertItemWithTitleNSMenu[] = {
    499       &Ctx.Idents.get("insertItemWithTitle"), &Ctx.Idents.get("action"),
    500       &Ctx.Idents.get("keyEquivalent"), &Ctx.Idents.get("atIndex")};
    501   ADD_METHOD(NSMenu, insertItemWithTitleNSMenu, 4, 0)
    502   IdentifierInfo *addItemWithTitleNSMenu[] = {
    503       &Ctx.Idents.get("addItemWithTitle"), &Ctx.Idents.get("action"),
    504       &Ctx.Idents.get("keyEquivalent")};
    505   ADD_METHOD(NSMenu, addItemWithTitleNSMenu, 3, 0)
    506   ADD_UNARY_METHOD(NSMenu, setTitle, 0)
    507 
    508   NEW_RECEIVER(UIMutableUserNotificationAction)
    509   ADD_UNARY_METHOD(UIMutableUserNotificationAction, setTitle, 0)
    510 
    511   NEW_RECEIVER(NSForm)
    512   ADD_UNARY_METHOD(NSForm, addEntry, 0)
    513   IdentifierInfo *insertEntryNSForm[] = {&Ctx.Idents.get("insertEntry"),
    514                                          &Ctx.Idents.get("atIndex")};
    515   ADD_METHOD(NSForm, insertEntryNSForm, 2, 0)
    516 
    517   NEW_RECEIVER(NSTextFieldCell)
    518   ADD_UNARY_METHOD(NSTextFieldCell, setPlaceholderString, 0)
    519 
    520   NEW_RECEIVER(NSUserNotificationAction)
    521   IdentifierInfo *actionWithIdentifierNSUserNotificationAction[] = {
    522       &Ctx.Idents.get("actionWithIdentifier"), &Ctx.Idents.get("title")};
    523   ADD_METHOD(NSUserNotificationAction,
    524              actionWithIdentifierNSUserNotificationAction, 2, 1)
    525 
    526   NEW_RECEIVER(NSURLSession)
    527   ADD_UNARY_METHOD(NSURLSession, setSessionDescription, 0)
    528 
    529   NEW_RECEIVER(UITextField)
    530   ADD_UNARY_METHOD(UITextField, setText, 0)
    531   ADD_UNARY_METHOD(UITextField, setPlaceholder, 0)
    532 
    533   NEW_RECEIVER(UIBarButtonItem)
    534   IdentifierInfo *initWithTitleUIBarButtonItem[] = {
    535       &Ctx.Idents.get("initWithTitle"), &Ctx.Idents.get("style"),
    536       &Ctx.Idents.get("target"), &Ctx.Idents.get("action")};
    537   ADD_METHOD(UIBarButtonItem, initWithTitleUIBarButtonItem, 4, 0)
    538 
    539   NEW_RECEIVER(UIViewController)
    540   ADD_UNARY_METHOD(UIViewController, setTitle, 0)
    541 
    542   NEW_RECEIVER(UISegmentedControl)
    543   IdentifierInfo *insertSegmentWithTitleUISegmentedControl[] = {
    544       &Ctx.Idents.get("insertSegmentWithTitle"), &Ctx.Idents.get("atIndex"),
    545       &Ctx.Idents.get("animated")};
    546   ADD_METHOD(UISegmentedControl, insertSegmentWithTitleUISegmentedControl, 3, 0)
    547   IdentifierInfo *setTitleUISegmentedControl[] = {
    548       &Ctx.Idents.get("setTitle"), &Ctx.Idents.get("forSegmentAtIndex")};
    549   ADD_METHOD(UISegmentedControl, setTitleUISegmentedControl, 2, 0)
    550 }
    551 
    552 #define LSF_INSERT(function_name) LSF.insert(&Ctx.Idents.get(function_name));
    553 #define LSM_INSERT_NULLARY(receiver, method_name)                              \
    554   LSM.insert({&Ctx.Idents.get(receiver), Ctx.Selectors.getNullarySelector(     \
    555                                              &Ctx.Idents.get(method_name))});
    556 #define LSM_INSERT_UNARY(receiver, method_name)                                \
    557   LSM.insert({&Ctx.Idents.get(receiver),                                       \
    558               Ctx.Selectors.getUnarySelector(&Ctx.Idents.get(method_name))});
    559 #define LSM_INSERT_SELECTOR(receiver, method_list, arguments)                  \
    560   LSM.insert({&Ctx.Idents.get(receiver),                                       \
    561               Ctx.Selectors.getSelector(arguments, method_list)});
    562 
    563 /// Initializes a list of methods and C functions that return a localized string
    564 void NonLocalizedStringChecker::initLocStringsMethods(ASTContext &Ctx) const {
    565   if (!LSM.empty())
    566     return;
    567 
    568   IdentifierInfo *LocalizedStringMacro[] = {
    569       &Ctx.Idents.get("localizedStringForKey"), &Ctx.Idents.get("value"),
    570       &Ctx.Idents.get("table")};
    571   LSM_INSERT_SELECTOR("NSBundle", LocalizedStringMacro, 3)
    572   LSM_INSERT_UNARY("NSDateFormatter", "stringFromDate")
    573   IdentifierInfo *LocalizedStringFromDate[] = {
    574       &Ctx.Idents.get("localizedStringFromDate"), &Ctx.Idents.get("dateStyle"),
    575       &Ctx.Idents.get("timeStyle")};
    576   LSM_INSERT_SELECTOR("NSDateFormatter", LocalizedStringFromDate, 3)
    577   LSM_INSERT_UNARY("NSNumberFormatter", "stringFromNumber")
    578   LSM_INSERT_NULLARY("UITextField", "text")
    579   LSM_INSERT_NULLARY("UITextView", "text")
    580   LSM_INSERT_NULLARY("UILabel", "text")
    581 
    582   LSF_INSERT("CFDateFormatterCreateStringWithDate");
    583   LSF_INSERT("CFDateFormatterCreateStringWithAbsoluteTime");
    584   LSF_INSERT("CFNumberFormatterCreateStringWithNumber");
    585 }
    586 
    587 /// Checks to see if the method / function declaration includes
    588 /// __attribute__((annotate("returns_localized_nsstring")))
    589 bool NonLocalizedStringChecker::isAnnotatedAsLocalized(const Decl *D) const {
    590   if (!D)
    591     return false;
    592   return std::any_of(
    593       D->specific_attr_begin<AnnotateAttr>(),
    594       D->specific_attr_end<AnnotateAttr>(), [](const AnnotateAttr *Ann) {
    595         return Ann->getAnnotation() == "returns_localized_nsstring";
    596       });
    597 }
    598 
    599 /// Returns true if the given SVal is marked as Localized in the program state
    600 bool NonLocalizedStringChecker::hasLocalizedState(SVal S,
    601                                                   CheckerContext &C) const {
    602   const MemRegion *mt = S.getAsRegion();
    603   if (mt) {
    604     const LocalizedState *LS = C.getState()->get<LocalizedMemMap>(mt);
    605     if (LS && LS->isLocalized())
    606       return true;
    607   }
    608   return false;
    609 }
    610 
    611 /// Returns true if the given SVal is marked as NonLocalized in the program
    612 /// state
    613 bool NonLocalizedStringChecker::hasNonLocalizedState(SVal S,
    614                                                      CheckerContext &C) const {
    615   const MemRegion *mt = S.getAsRegion();
    616   if (mt) {
    617     const LocalizedState *LS = C.getState()->get<LocalizedMemMap>(mt);
    618     if (LS && LS->isNonLocalized())
    619       return true;
    620   }
    621   return false;
    622 }
    623 
    624 /// Marks the given SVal as Localized in the program state
    625 void NonLocalizedStringChecker::setLocalizedState(const SVal S,
    626                                                   CheckerContext &C) const {
    627   const MemRegion *mt = S.getAsRegion();
    628   if (mt) {
    629     ProgramStateRef State =
    630         C.getState()->set<LocalizedMemMap>(mt, LocalizedState::getLocalized());
    631     C.addTransition(State);
    632   }
    633 }
    634 
    635 /// Marks the given SVal as NonLocalized in the program state
    636 void NonLocalizedStringChecker::setNonLocalizedState(const SVal S,
    637                                                      CheckerContext &C) const {
    638   const MemRegion *mt = S.getAsRegion();
    639   if (mt) {
    640     ProgramStateRef State = C.getState()->set<LocalizedMemMap>(
    641         mt, LocalizedState::getNonLocalized());
    642     C.addTransition(State);
    643   }
    644 }
    645 
    646 
    647 static bool isDebuggingName(std::string name) {
    648   return StringRef(name).lower().find("debug") != StringRef::npos;
    649 }
    650 
    651 /// Returns true when, heuristically, the analyzer may be analyzing debugging
    652 /// code. We use this to suppress localization diagnostics in un-localized user
    653 /// interfaces that are only used for debugging and are therefore not user
    654 /// facing.
    655 static bool isDebuggingContext(CheckerContext &C) {
    656   const Decl *D = C.getCurrentAnalysisDeclContext()->getDecl();
    657   if (!D)
    658     return false;
    659 
    660   if (auto *ND = dyn_cast<NamedDecl>(D)) {
    661     if (isDebuggingName(ND->getNameAsString()))
    662       return true;
    663   }
    664 
    665   const DeclContext *DC = D->getDeclContext();
    666 
    667   if (auto *CD = dyn_cast<ObjCContainerDecl>(DC)) {
    668     if (isDebuggingName(CD->getNameAsString()))
    669       return true;
    670   }
    671 
    672   return false;
    673 }
    674 
    675 
    676 /// Reports a localization error for the passed in method call and SVal
    677 void NonLocalizedStringChecker::reportLocalizationError(
    678     SVal S, const ObjCMethodCall &M, CheckerContext &C,
    679     int argumentNumber) const {
    680 
    681   // Don't warn about localization errors in classes and methods that
    682   // may be debug code.
    683   if (isDebuggingContext(C))
    684     return;
    685 
    686   ExplodedNode *ErrNode = C.getPredecessor();
    687   static CheckerProgramPointTag Tag("NonLocalizedStringChecker",
    688                                     "UnlocalizedString");
    689   ErrNode = C.addTransition(C.getState(), C.getPredecessor(), &Tag);
    690 
    691   if (!ErrNode)
    692     return;
    693 
    694   // Generate the bug report.
    695   std::unique_ptr<BugReport> R(new BugReport(
    696       *BT, "User-facing text should use localized string macro", ErrNode));
    697   if (argumentNumber) {
    698     R->addRange(M.getArgExpr(argumentNumber - 1)->getSourceRange());
    699   } else {
    700     R->addRange(M.getSourceRange());
    701   }
    702   R->markInteresting(S);
    703 
    704   const MemRegion *StringRegion = S.getAsRegion();
    705   if (StringRegion)
    706     R->addVisitor(llvm::make_unique<NonLocalizedStringBRVisitor>(StringRegion));
    707 
    708   C.emitReport(std::move(R));
    709 }
    710 
    711 /// Returns the argument number requiring localized string if it exists
    712 /// otherwise, returns -1
    713 int NonLocalizedStringChecker::getLocalizedArgumentForSelector(
    714     const IdentifierInfo *Receiver, Selector S) const {
    715   auto method = UIMethods.find(Receiver);
    716 
    717   if (method == UIMethods.end())
    718     return -1;
    719 
    720   auto argumentIterator = method->getSecond().find(S);
    721 
    722   if (argumentIterator == method->getSecond().end())
    723     return -1;
    724 
    725   int argumentNumber = argumentIterator->getSecond();
    726   return argumentNumber;
    727 }
    728 
    729 /// Check if the string being passed in has NonLocalized state
    730 void NonLocalizedStringChecker::checkPreObjCMessage(const ObjCMethodCall &msg,
    731                                                     CheckerContext &C) const {
    732   initUIMethods(C.getASTContext());
    733 
    734   const ObjCInterfaceDecl *OD = msg.getReceiverInterface();
    735   if (!OD)
    736     return;
    737   const IdentifierInfo *odInfo = OD->getIdentifier();
    738 
    739   Selector S = msg.getSelector();
    740 
    741   std::string SelectorString = S.getAsString();
    742   StringRef SelectorName = SelectorString;
    743   assert(!SelectorName.empty());
    744 
    745   if (odInfo->isStr("NSString")) {
    746     // Handle the case where the receiver is an NSString
    747     // These special NSString methods draw to the screen
    748 
    749     if (!(SelectorName.startswith("drawAtPoint") ||
    750           SelectorName.startswith("drawInRect") ||
    751           SelectorName.startswith("drawWithRect")))
    752       return;
    753 
    754     SVal svTitle = msg.getReceiverSVal();
    755 
    756     bool isNonLocalized = hasNonLocalizedState(svTitle, C);
    757 
    758     if (isNonLocalized) {
    759       reportLocalizationError(svTitle, msg, C);
    760     }
    761   }
    762 
    763   int argumentNumber = getLocalizedArgumentForSelector(odInfo, S);
    764   // Go up each hierarchy of superclasses and their protocols
    765   while (argumentNumber < 0 && OD->getSuperClass() != nullptr) {
    766     for (const auto *P : OD->all_referenced_protocols()) {
    767       argumentNumber = getLocalizedArgumentForSelector(P->getIdentifier(), S);
    768       if (argumentNumber >= 0)
    769         break;
    770     }
    771     if (argumentNumber < 0) {
    772       OD = OD->getSuperClass();
    773       argumentNumber = getLocalizedArgumentForSelector(OD->getIdentifier(), S);
    774     }
    775   }
    776 
    777   if (argumentNumber < 0) // There was no match in UIMethods
    778     return;
    779 
    780   SVal svTitle = msg.getArgSVal(argumentNumber);
    781 
    782   if (const ObjCStringRegion *SR =
    783           dyn_cast_or_null<ObjCStringRegion>(svTitle.getAsRegion())) {
    784     StringRef stringValue =
    785         SR->getObjCStringLiteral()->getString()->getString();
    786     if ((stringValue.trim().size() == 0 && stringValue.size() > 0) ||
    787         stringValue.empty())
    788       return;
    789     if (!IsAggressive && llvm::sys::unicode::columnWidthUTF8(stringValue) < 2)
    790       return;
    791   }
    792 
    793   bool isNonLocalized = hasNonLocalizedState(svTitle, C);
    794 
    795   if (isNonLocalized) {
    796     reportLocalizationError(svTitle, msg, C, argumentNumber + 1);
    797   }
    798 }
    799 
    800 static inline bool isNSStringType(QualType T, ASTContext &Ctx) {
    801 
    802   const ObjCObjectPointerType *PT = T->getAs<ObjCObjectPointerType>();
    803   if (!PT)
    804     return false;
    805 
    806   ObjCInterfaceDecl *Cls = PT->getObjectType()->getInterface();
    807   if (!Cls)
    808     return false;
    809 
    810   IdentifierInfo *ClsName = Cls->getIdentifier();
    811 
    812   // FIXME: Should we walk the chain of classes?
    813   return ClsName == &Ctx.Idents.get("NSString") ||
    814          ClsName == &Ctx.Idents.get("NSMutableString");
    815 }
    816 
    817 /// Marks a string being returned by any call as localized
    818 /// if it is in LocStringFunctions (LSF) or the function is annotated.
    819 /// Otherwise, we mark it as NonLocalized (Aggressive) or
    820 /// NonLocalized only if it is not backed by a SymRegion (Non-Aggressive),
    821 /// basically leaving only string literals as NonLocalized.
    822 void NonLocalizedStringChecker::checkPostCall(const CallEvent &Call,
    823                                               CheckerContext &C) const {
    824   initLocStringsMethods(C.getASTContext());
    825 
    826   if (!Call.getOriginExpr())
    827     return;
    828 
    829   // Anything that takes in a localized NSString as an argument
    830   // and returns an NSString will be assumed to be returning a
    831   // localized NSString. (Counter: Incorrectly combining two LocalizedStrings)
    832   const QualType RT = Call.getResultType();
    833   if (isNSStringType(RT, C.getASTContext())) {
    834     for (unsigned i = 0; i < Call.getNumArgs(); ++i) {
    835       SVal argValue = Call.getArgSVal(i);
    836       if (hasLocalizedState(argValue, C)) {
    837         SVal sv = Call.getReturnValue();
    838         setLocalizedState(sv, C);
    839         return;
    840       }
    841     }
    842   }
    843 
    844   const Decl *D = Call.getDecl();
    845   if (!D)
    846     return;
    847 
    848   const IdentifierInfo *Identifier = Call.getCalleeIdentifier();
    849 
    850   SVal sv = Call.getReturnValue();
    851   if (isAnnotatedAsLocalized(D) || LSF.count(Identifier) != 0) {
    852     setLocalizedState(sv, C);
    853   } else if (isNSStringType(RT, C.getASTContext()) &&
    854              !hasLocalizedState(sv, C)) {
    855     if (IsAggressive) {
    856       setNonLocalizedState(sv, C);
    857     } else {
    858       const SymbolicRegion *SymReg =
    859           dyn_cast_or_null<SymbolicRegion>(sv.getAsRegion());
    860       if (!SymReg)
    861         setNonLocalizedState(sv, C);
    862     }
    863   }
    864 }
    865 
    866 /// Marks a string being returned by an ObjC method as localized
    867 /// if it is in LocStringMethods or the method is annotated
    868 void NonLocalizedStringChecker::checkPostObjCMessage(const ObjCMethodCall &msg,
    869                                                      CheckerContext &C) const {
    870   initLocStringsMethods(C.getASTContext());
    871 
    872   if (!msg.isInstanceMessage())
    873     return;
    874 
    875   const ObjCInterfaceDecl *OD = msg.getReceiverInterface();
    876   if (!OD)
    877     return;
    878   const IdentifierInfo *odInfo = OD->getIdentifier();
    879 
    880   Selector S = msg.getSelector();
    881   std::string SelectorName = S.getAsString();
    882 
    883   std::pair<const IdentifierInfo *, Selector> MethodDescription = {odInfo, S};
    884 
    885   if (LSM.count(MethodDescription) || isAnnotatedAsLocalized(msg.getDecl())) {
    886     SVal sv = msg.getReturnValue();
    887     setLocalizedState(sv, C);
    888   }
    889 }
    890 
    891 /// Marks all empty string literals as localized
    892 void NonLocalizedStringChecker::checkPostStmt(const ObjCStringLiteral *SL,
    893                                               CheckerContext &C) const {
    894   SVal sv = C.getSVal(SL);
    895   setNonLocalizedState(sv, C);
    896 }
    897 
    898 PathDiagnosticPiece *
    899 NonLocalizedStringBRVisitor::VisitNode(const ExplodedNode *Succ,
    900                                        const ExplodedNode *Pred,
    901                                        BugReporterContext &BRC, BugReport &BR) {
    902   if (Satisfied)
    903     return nullptr;
    904 
    905   Optional<StmtPoint> Point = Succ->getLocation().getAs<StmtPoint>();
    906   if (!Point.hasValue())
    907     return nullptr;
    908 
    909   auto *LiteralExpr = dyn_cast<ObjCStringLiteral>(Point->getStmt());
    910   if (!LiteralExpr)
    911     return nullptr;
    912 
    913   ProgramStateRef State = Succ->getState();
    914   SVal LiteralSVal = State->getSVal(LiteralExpr, Succ->getLocationContext());
    915   if (LiteralSVal.getAsRegion() != NonLocalizedString)
    916     return nullptr;
    917 
    918   Satisfied = true;
    919 
    920   PathDiagnosticLocation L =
    921       PathDiagnosticLocation::create(*Point, BRC.getSourceManager());
    922 
    923   if (!L.isValid() || !L.asLocation().isValid())
    924     return nullptr;
    925 
    926   auto *Piece = new PathDiagnosticEventPiece(L,
    927       "Non-localized string literal here");
    928   Piece->addRange(LiteralExpr->getSourceRange());
    929 
    930   return Piece;
    931 }
    932 
    933 namespace {
    934 class EmptyLocalizationContextChecker
    935     : public Checker<check::ASTDecl<ObjCImplementationDecl>> {
    936 
    937   // A helper class, which walks the AST
    938   class MethodCrawler : public ConstStmtVisitor<MethodCrawler> {
    939     const ObjCMethodDecl *MD;
    940     BugReporter &BR;
    941     AnalysisManager &Mgr;
    942     const CheckerBase *Checker;
    943     LocationOrAnalysisDeclContext DCtx;
    944 
    945   public:
    946     MethodCrawler(const ObjCMethodDecl *InMD, BugReporter &InBR,
    947                   const CheckerBase *Checker, AnalysisManager &InMgr,
    948                   AnalysisDeclContext *InDCtx)
    949         : MD(InMD), BR(InBR), Mgr(InMgr), Checker(Checker), DCtx(InDCtx) {}
    950 
    951     void VisitStmt(const Stmt *S) { VisitChildren(S); }
    952 
    953     void VisitObjCMessageExpr(const ObjCMessageExpr *ME);
    954 
    955     void reportEmptyContextError(const ObjCMessageExpr *M) const;
    956 
    957     void VisitChildren(const Stmt *S) {
    958       for (const Stmt *Child : S->children()) {
    959         if (Child)
    960           this->Visit(Child);
    961       }
    962     }
    963   };
    964 
    965 public:
    966   void checkASTDecl(const ObjCImplementationDecl *D, AnalysisManager &Mgr,
    967                     BugReporter &BR) const;
    968 };
    969 } // end anonymous namespace
    970 
    971 void EmptyLocalizationContextChecker::checkASTDecl(
    972     const ObjCImplementationDecl *D, AnalysisManager &Mgr,
    973     BugReporter &BR) const {
    974 
    975   for (const ObjCMethodDecl *M : D->methods()) {
    976     AnalysisDeclContext *DCtx = Mgr.getAnalysisDeclContext(M);
    977 
    978     const Stmt *Body = M->getBody();
    979     assert(Body);
    980 
    981     MethodCrawler MC(M->getCanonicalDecl(), BR, this, Mgr, DCtx);
    982     MC.VisitStmt(Body);
    983   }
    984 }
    985 
    986 /// This check attempts to match these macros, assuming they are defined as
    987 /// follows:
    988 ///
    989 /// #define NSLocalizedString(key, comment) \
    990 /// [[NSBundle mainBundle] localizedStringForKey:(key) value:@"" table:nil]
    991 /// #define NSLocalizedStringFromTable(key, tbl, comment) \
    992 /// [[NSBundle mainBundle] localizedStringForKey:(key) value:@"" table:(tbl)]
    993 /// #define NSLocalizedStringFromTableInBundle(key, tbl, bundle, comment) \
    994 /// [bundle localizedStringForKey:(key) value:@"" table:(tbl)]
    995 /// #define NSLocalizedStringWithDefaultValue(key, tbl, bundle, val, comment)
    996 ///
    997 /// We cannot use the path sensitive check because the macro argument we are
    998 /// checking for (comment) is not used and thus not present in the AST,
    999 /// so we use Lexer on the original macro call and retrieve the value of
   1000 /// the comment. If it's empty or nil, we raise a warning.
   1001 void EmptyLocalizationContextChecker::MethodCrawler::VisitObjCMessageExpr(
   1002     const ObjCMessageExpr *ME) {
   1003 
   1004   const ObjCInterfaceDecl *OD = ME->getReceiverInterface();
   1005   if (!OD)
   1006     return;
   1007 
   1008   const IdentifierInfo *odInfo = OD->getIdentifier();
   1009 
   1010   if (!(odInfo->isStr("NSBundle") &&
   1011         ME->getSelector().getAsString() ==
   1012             "localizedStringForKey:value:table:")) {
   1013     return;
   1014   }
   1015 
   1016   SourceRange R = ME->getSourceRange();
   1017   if (!R.getBegin().isMacroID())
   1018     return;
   1019 
   1020   // getImmediateMacroCallerLoc gets the location of the immediate macro
   1021   // caller, one level up the stack toward the initial macro typed into the
   1022   // source, so SL should point to the NSLocalizedString macro.
   1023   SourceLocation SL =
   1024       Mgr.getSourceManager().getImmediateMacroCallerLoc(R.getBegin());
   1025   std::pair<FileID, unsigned> SLInfo =
   1026       Mgr.getSourceManager().getDecomposedLoc(SL);
   1027 
   1028   SrcMgr::SLocEntry SE = Mgr.getSourceManager().getSLocEntry(SLInfo.first);
   1029 
   1030   // If NSLocalizedString macro is wrapped in another macro, we need to
   1031   // unwrap the expansion until we get to the NSLocalizedStringMacro.
   1032   while (SE.isExpansion()) {
   1033     SL = SE.getExpansion().getSpellingLoc();
   1034     SLInfo = Mgr.getSourceManager().getDecomposedLoc(SL);
   1035     SE = Mgr.getSourceManager().getSLocEntry(SLInfo.first);
   1036   }
   1037 
   1038   llvm::MemoryBuffer *BF = SE.getFile().getContentCache()->getRawBuffer();
   1039   Lexer TheLexer(SL, LangOptions(), BF->getBufferStart(),
   1040                  BF->getBufferStart() + SLInfo.second, BF->getBufferEnd());
   1041 
   1042   Token I;
   1043   Token Result;    // This will hold the token just before the last ')'
   1044   int p_count = 0; // This is for parenthesis matching
   1045   while (!TheLexer.LexFromRawLexer(I)) {
   1046     if (I.getKind() == tok::l_paren)
   1047       ++p_count;
   1048     if (I.getKind() == tok::r_paren) {
   1049       if (p_count == 1)
   1050         break;
   1051       --p_count;
   1052     }
   1053     Result = I;
   1054   }
   1055 
   1056   if (isAnyIdentifier(Result.getKind())) {
   1057     if (Result.getRawIdentifier().equals("nil")) {
   1058       reportEmptyContextError(ME);
   1059       return;
   1060     }
   1061   }
   1062 
   1063   if (!isStringLiteral(Result.getKind()))
   1064     return;
   1065 
   1066   StringRef Comment =
   1067       StringRef(Result.getLiteralData(), Result.getLength()).trim('"');
   1068 
   1069   if ((Comment.trim().size() == 0 && Comment.size() > 0) || // Is Whitespace
   1070       Comment.empty()) {
   1071     reportEmptyContextError(ME);
   1072   }
   1073 }
   1074 
   1075 void EmptyLocalizationContextChecker::MethodCrawler::reportEmptyContextError(
   1076     const ObjCMessageExpr *ME) const {
   1077   // Generate the bug report.
   1078   BR.EmitBasicReport(MD, Checker, "Context Missing",
   1079                      "Localizability Issue (Apple)",
   1080                      "Localized string macro should include a non-empty "
   1081                      "comment for translators",
   1082                      PathDiagnosticLocation(ME, BR.getSourceManager(), DCtx));
   1083 }
   1084 
   1085 namespace {
   1086 class PluralMisuseChecker : public Checker<check::ASTCodeBody> {
   1087 
   1088   // A helper class, which walks the AST
   1089   class MethodCrawler : public RecursiveASTVisitor<MethodCrawler> {
   1090     BugReporter &BR;
   1091     const CheckerBase *Checker;
   1092     AnalysisDeclContext *AC;
   1093 
   1094     // This functions like a stack. We push on any IfStmt or
   1095     // ConditionalOperator that matches the condition
   1096     // and pop it off when we leave that statement
   1097     llvm::SmallVector<const clang::Stmt *, 8> MatchingStatements;
   1098     // This is true when we are the direct-child of a
   1099     // matching statement
   1100     bool InMatchingStatement = false;
   1101 
   1102   public:
   1103     explicit MethodCrawler(BugReporter &InBR, const CheckerBase *Checker,
   1104                            AnalysisDeclContext *InAC)
   1105         : BR(InBR), Checker(Checker), AC(InAC) {}
   1106 
   1107     bool VisitIfStmt(const IfStmt *I);
   1108     bool EndVisitIfStmt(IfStmt *I);
   1109     bool TraverseIfStmt(IfStmt *x);
   1110     bool VisitConditionalOperator(const ConditionalOperator *C);
   1111     bool TraverseConditionalOperator(ConditionalOperator *C);
   1112     bool VisitCallExpr(const CallExpr *CE);
   1113     bool VisitObjCMessageExpr(const ObjCMessageExpr *ME);
   1114 
   1115   private:
   1116     void reportPluralMisuseError(const Stmt *S) const;
   1117     bool isCheckingPlurality(const Expr *E) const;
   1118   };
   1119 
   1120 public:
   1121   void checkASTCodeBody(const Decl *D, AnalysisManager &Mgr,
   1122                         BugReporter &BR) const {
   1123     MethodCrawler Visitor(BR, this, Mgr.getAnalysisDeclContext(D));
   1124     Visitor.TraverseDecl(const_cast<Decl *>(D));
   1125   }
   1126 };
   1127 } // end anonymous namespace
   1128 
   1129 // Checks the condition of the IfStmt and returns true if one
   1130 // of the following heuristics are met:
   1131 // 1) The conidtion is a variable with "singular" or "plural" in the name
   1132 // 2) The condition is a binary operator with 1 or 2 on the right-hand side
   1133 bool PluralMisuseChecker::MethodCrawler::isCheckingPlurality(
   1134     const Expr *Condition) const {
   1135   const BinaryOperator *BO = nullptr;
   1136   // Accounts for when a VarDecl represents a BinaryOperator
   1137   if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Condition)) {
   1138     if (const VarDecl *VD = dyn_cast<VarDecl>(DRE->getDecl())) {
   1139       const Expr *InitExpr = VD->getInit();
   1140       if (InitExpr) {
   1141         if (const BinaryOperator *B =
   1142                 dyn_cast<BinaryOperator>(InitExpr->IgnoreParenImpCasts())) {
   1143           BO = B;
   1144         }
   1145       }
   1146       if (VD->getName().lower().find("plural") != StringRef::npos ||
   1147           VD->getName().lower().find("singular") != StringRef::npos) {
   1148         return true;
   1149       }
   1150     }
   1151   } else if (const BinaryOperator *B = dyn_cast<BinaryOperator>(Condition)) {
   1152     BO = B;
   1153   }
   1154 
   1155   if (BO == nullptr)
   1156     return false;
   1157 
   1158   if (IntegerLiteral *IL = dyn_cast_or_null<IntegerLiteral>(
   1159           BO->getRHS()->IgnoreParenImpCasts())) {
   1160     llvm::APInt Value = IL->getValue();
   1161     if (Value == 1 || Value == 2) {
   1162       return true;
   1163     }
   1164   }
   1165   return false;
   1166 }
   1167 
   1168 // A CallExpr with "LOC" in its identifier that takes in a string literal
   1169 // has been shown to almost always be a function that returns a localized
   1170 // string. Raise a diagnostic when this is in a statement that matches
   1171 // the condition.
   1172 bool PluralMisuseChecker::MethodCrawler::VisitCallExpr(const CallExpr *CE) {
   1173   if (InMatchingStatement) {
   1174     if (const FunctionDecl *FD = CE->getDirectCallee()) {
   1175       std::string NormalizedName =
   1176           StringRef(FD->getNameInfo().getAsString()).lower();
   1177       if (NormalizedName.find("loc") != std::string::npos) {
   1178         for (const Expr *Arg : CE->arguments()) {
   1179           if (isa<ObjCStringLiteral>(Arg))
   1180             reportPluralMisuseError(CE);
   1181         }
   1182       }
   1183     }
   1184   }
   1185   return true;
   1186 }
   1187 
   1188 // The other case is for NSLocalizedString which also returns
   1189 // a localized string. It's a macro for the ObjCMessageExpr
   1190 // [NSBundle localizedStringForKey:value:table:] Raise a
   1191 // diagnostic when this is in a statement that matches
   1192 // the condition.
   1193 bool PluralMisuseChecker::MethodCrawler::VisitObjCMessageExpr(
   1194     const ObjCMessageExpr *ME) {
   1195   const ObjCInterfaceDecl *OD = ME->getReceiverInterface();
   1196   if (!OD)
   1197     return true;
   1198 
   1199   const IdentifierInfo *odInfo = OD->getIdentifier();
   1200 
   1201   if (odInfo->isStr("NSBundle") &&
   1202       ME->getSelector().getAsString() == "localizedStringForKey:value:table:") {
   1203     if (InMatchingStatement) {
   1204       reportPluralMisuseError(ME);
   1205     }
   1206   }
   1207   return true;
   1208 }
   1209 
   1210 /// Override TraverseIfStmt so we know when we are done traversing an IfStmt
   1211 bool PluralMisuseChecker::MethodCrawler::TraverseIfStmt(IfStmt *I) {
   1212   RecursiveASTVisitor<MethodCrawler>::TraverseIfStmt(I);
   1213   return EndVisitIfStmt(I);
   1214 }
   1215 
   1216 // EndVisit callbacks are not provided by the RecursiveASTVisitor
   1217 // so we override TraverseIfStmt and make a call to EndVisitIfStmt
   1218 // after traversing the IfStmt
   1219 bool PluralMisuseChecker::MethodCrawler::EndVisitIfStmt(IfStmt *I) {
   1220   MatchingStatements.pop_back();
   1221   if (!MatchingStatements.empty()) {
   1222     if (MatchingStatements.back() != nullptr) {
   1223       InMatchingStatement = true;
   1224       return true;
   1225     }
   1226   }
   1227   InMatchingStatement = false;
   1228   return true;
   1229 }
   1230 
   1231 bool PluralMisuseChecker::MethodCrawler::VisitIfStmt(const IfStmt *I) {
   1232   const Expr *Condition = I->getCond()->IgnoreParenImpCasts();
   1233   if (isCheckingPlurality(Condition)) {
   1234     MatchingStatements.push_back(I);
   1235     InMatchingStatement = true;
   1236   } else {
   1237     MatchingStatements.push_back(nullptr);
   1238     InMatchingStatement = false;
   1239   }
   1240 
   1241   return true;
   1242 }
   1243 
   1244 // Preliminary support for conditional operators.
   1245 bool PluralMisuseChecker::MethodCrawler::TraverseConditionalOperator(
   1246     ConditionalOperator *C) {
   1247   RecursiveASTVisitor<MethodCrawler>::TraverseConditionalOperator(C);
   1248   MatchingStatements.pop_back();
   1249   if (!MatchingStatements.empty()) {
   1250     if (MatchingStatements.back() != nullptr)
   1251       InMatchingStatement = true;
   1252     else
   1253       InMatchingStatement = false;
   1254   } else {
   1255     InMatchingStatement = false;
   1256   }
   1257   return true;
   1258 }
   1259 
   1260 bool PluralMisuseChecker::MethodCrawler::VisitConditionalOperator(
   1261     const ConditionalOperator *C) {
   1262   const Expr *Condition = C->getCond()->IgnoreParenImpCasts();
   1263   if (isCheckingPlurality(Condition)) {
   1264     MatchingStatements.push_back(C);
   1265     InMatchingStatement = true;
   1266   } else {
   1267     MatchingStatements.push_back(nullptr);
   1268     InMatchingStatement = false;
   1269   }
   1270   return true;
   1271 }
   1272 
   1273 void PluralMisuseChecker::MethodCrawler::reportPluralMisuseError(
   1274     const Stmt *S) const {
   1275   // Generate the bug report.
   1276   BR.EmitBasicReport(AC->getDecl(), Checker, "Plural Misuse",
   1277                      "Localizability Issue (Apple)",
   1278                      "Plural cases are not supported accross all languages. "
   1279                      "Use a .stringsdict file instead",
   1280                      PathDiagnosticLocation(S, BR.getSourceManager(), AC));
   1281 }
   1282 
   1283 //===----------------------------------------------------------------------===//
   1284 // Checker registration.
   1285 //===----------------------------------------------------------------------===//
   1286 
   1287 void ento::registerNonLocalizedStringChecker(CheckerManager &mgr) {
   1288   NonLocalizedStringChecker *checker =
   1289       mgr.registerChecker<NonLocalizedStringChecker>();
   1290   checker->IsAggressive =
   1291       mgr.getAnalyzerOptions().getBooleanOption("AggressiveReport", false);
   1292 }
   1293 
   1294 void ento::registerEmptyLocalizationContextChecker(CheckerManager &mgr) {
   1295   mgr.registerChecker<EmptyLocalizationContextChecker>();
   1296 }
   1297 
   1298 void ento::registerPluralMisuseChecker(CheckerManager &mgr) {
   1299   mgr.registerChecker<PluralMisuseChecker>();
   1300 }
   1301