[analyzer] Add checkers for OS X / iOS localizability issues

Add checkers that detect code-level localizability issues for OS X / iOS:
  - A path sensitive checker that warns about uses of non-localized
    NSStrings passed to UI methods expecting localized strings.
  - A syntax checker that warns against not including a comment in
    NSLocalizedString macros.

A patch by Kulpreet Chilana!

(This is the second attempt with the compilation issue on Windows and
the random test failures resolved.)

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@245093 91177308-0d34-0410-b5e6-96231b3b80d8

lib/StaticAnalyzer/Checkers/CMakeLists.txt

@@ -39,6 +39,7 @@ add_clang_library(clangStaticAnalyzerCheckers
   IdenticalExprChecker.cpp
   IvarInvalidationChecker.cpp
   LLVMConventionsChecker.cpp
+  LocalizationChecker.cpp
   MacOSKeychainAPIChecker.cpp
   MacOSXAPIChecker.cpp
   MallocChecker.cpp

lib/StaticAnalyzer/Checkers/Checkers.td

@@ -452,6 +452,14 @@ def DirectIvarAssignmentForAnnotatedFunctions : Checker<"DirectIvarAssignmentFor
   HelpText<"Check for direct assignments to instance variables in the methods annotated with objc_no_direct_instance_variable_assignment">,
   DescFile<"DirectIvarAssignment.cpp">;
 
+def NonLocalizedStringChecker : Checker<"NonLocalizedStringChecker">,
+  HelpText<"Warns about uses of non-localized NSStrings passed to UI methods expecting localized NSStrings">,
+  DescFile<"LocalizationChecker.cpp">;
+
+def EmptyLocalizationContextChecker : Checker<"EmptyLocalizationContextChecker">,
+  HelpText<"Check that NSLocalizedString macros include a comment for context">,
+  DescFile<"LocalizationChecker.cpp">;
+
 } // end "alpha.osx.cocoa"
 
 let ParentPackage = CoreFoundation in {

test/Analysis/localization-aggressive.m

+// RUN: %clang_cc1 -analyze -fblocks -analyzer-store=region  -analyzer-checker=alpha.osx.cocoa.NonLocalizedStringChecker -analyzer-checker=alpha.osx.cocoa.EmptyLocalizationContextChecker -verify  -analyzer-config AggressiveReport=true %s
+
+// These declarations were reduced using Delta-Debugging from Foundation.h
+// on Mac OS X.
+
+#define nil ((id)0)
+#define NSLocalizedString(key, comment)                                        \
+  [[NSBundle mainBundle] localizedStringForKey:(key) value:@"" table:nil]
+#define NSLocalizedStringFromTable(key, tbl, comment)                          \
+  [[NSBundle mainBundle] localizedStringForKey:(key) value:@"" table:(tbl)]
+#define NSLocalizedStringFromTableInBundle(key, tbl, bundle, comment)          \
+  [bundle localizedStringForKey:(key) value:@"" table:(tbl)]
+#define NSLocalizedStringWithDefaultValue(key, tbl, bundle, val, comment)      \
+  [bundle localizedStringForKey:(key) value:(val) table:(tbl)]
+#define CGFLOAT_TYPE double
+typedef CGFLOAT_TYPE CGFloat;
+struct CGPoint {
+  CGFloat x;
+  CGFloat y;
+};
+typedef struct CGPoint CGPoint;
+@interface NSObject
++ (id)alloc;
+- (id)init;
+@end
+@class NSDictionary;
+@interface NSString : NSObject
+- (void)drawAtPoint:(CGPoint)point withAttributes:(NSDictionary *)attrs;
++ (instancetype)localizedStringWithFormat:(NSString *)format, ...;
+@end
+@interface NSBundle : NSObject
++ (NSBundle *)mainBundle;
+- (NSString *)localizedStringForKey:(NSString *)key
+                              value:(NSString *)value
+                              table:(NSString *)tableName;
+@end
+@interface UILabel : NSObject
+@property(nullable, nonatomic, copy) NSString *text;
+- (void)accessibilitySetIdentification:(NSString *)ident;
+@end
+@interface TestObject : NSObject
+@property(strong) NSString *text;
+@end
+
+@interface LocalizationTestSuite : NSObject
+NSString *ForceLocalized(NSString *str)
+    __attribute__((annotate("returns_localized_nsstring")));
+CGPoint CGPointMake(CGFloat x, CGFloat y);
+int random();
+// This next one is a made up API
+NSString *CFNumberFormatterCreateStringWithNumber(float x);
++ (NSString *)forceLocalized:(NSString *)str
+    __attribute__((annotate("returns_localized_nsstring")));
+@end
+
+// Test cases begin here
+@implementation LocalizationTestSuite
+
+// A C-Funtion that returns a localized string because it has the
+// "returns_localized_nsstring" annotation
+NSString *ForceLocalized(NSString *str) { return str; }
+// An ObjC method that returns a localized string because it has the
+// "returns_localized_nsstring" annotation
++ (NSString *)forceLocalized:(NSString *)str {
+  return str;
+}
+
+// An ObjC method that returns a localized string
++ (NSString *)unLocalizedStringMethod {
+  return @"UnlocalizedString";
+}
+
+- (void)testLocalizationErrorDetectedOnPathway {
+  UILabel *testLabel = [[UILabel alloc] init];
+  NSString *bar = NSLocalizedString(@"Hello", @"Comment");
+
+  if (random()) {
+    bar = @"Unlocalized string";
+  }
+
+  [testLabel setText:bar]; // expected-warning {{String should be localized}}
+}
+
+- (void)testLocalizationErrorDetectedOnNSString {
+  NSString *bar = NSLocalizedString(@"Hello", @"Comment");
+
+  if (random()) {
+    bar = @"Unlocalized string";
+  }
+
+  [bar drawAtPoint:CGPointMake(0, 0) withAttributes:nil]; // expected-warning {{String should be localized}}
+}
+
+- (void)testNoLocalizationErrorDetectedFromCFunction {
+  UILabel *testLabel = [[UILabel alloc] init];
+  NSString *bar = CFNumberFormatterCreateStringWithNumber(1);
+
+  [testLabel setText:bar]; // no-warning
+}
+
+- (void)testAnnotationAddsLocalizedStateForCFunction {
+  UILabel *testLabel = [[UILabel alloc] init];
+  NSString *bar = NSLocalizedString(@"Hello", @"Comment");
+
+  if (random()) {
+    bar = @"Unlocalized string";
+  }
+
+  [testLabel setText:ForceLocalized(bar)]; // no-warning
+}
+
+- (void)testAnnotationAddsLocalizedStateForObjCMethod {
+  UILabel *testLabel = [[UILabel alloc] init];
+  NSString *bar = NSLocalizedString(@"Hello", @"Comment");
+
+  if (random()) {
+    bar = @"Unlocalized string";
+  }
+
+  [testLabel setText:[LocalizationTestSuite forceLocalized:bar]]; // no-warning
+}
+
+// An empty string literal @"" should not raise an error
+- (void)testEmptyStringLiteralHasLocalizedState {
+  UILabel *testLabel = [[UILabel alloc] init];
+  NSString *bar = @"";
+
+  [testLabel setText:bar]; // no-warning
+}
+
+// An empty string literal @"" inline should not raise an error
+- (void)testInlineEmptyStringLiteralHasLocalizedState {
+  UILabel *testLabel = [[UILabel alloc] init];
+  [testLabel setText:@""]; // no-warning
+}
+
+// An string literal @"Hello" inline should raise an error
+- (void)testInlineStringLiteralHasLocalizedState {
+  UILabel *testLabel = [[UILabel alloc] init];
+  [testLabel setText:@"Hello"]; // expected-warning {{String should be localized}}
+}
+
+// A nil string should not raise an error
+- (void)testNilStringIsNotMarkedAsUnlocalized {
+  UILabel *testLabel = [[UILabel alloc] init];
+  [testLabel setText:nil]; // no-warning
+}
+
+// A method that takes in a localized string and returns a string
+// most likely that string is localized.
+- (void)testLocalizedStringArgument {
+  UILabel *testLabel = [[UILabel alloc] init];
+  NSString *localizedString = NSLocalizedString(@"Hello", @"Comment");
+
+  NSString *combinedString =
+      [NSString localizedStringWithFormat:@"%@", localizedString];
+
+  [testLabel setText:combinedString]; // no-warning
+}
+
+// A String passed in as a an parameter should not be considered
+// unlocalized
+- (void)testLocalizedStringAsArgument:(NSString *)argumentString {
+  UILabel *testLabel = [[UILabel alloc] init];
+
+  [testLabel setText:argumentString]; // no-warning
+}
+
+// The warning is expected to be seen in localizedStringAsArgument: body
+- (void)testLocalizedStringAsArgumentOtherMethod:(NSString *)argumentString {
+  [self localizedStringAsArgument:@"UnlocalizedString"];
+}
+
+// A String passed into another method that calls a method that
+// requires a localized string should give an error
+- (void)localizedStringAsArgument:(NSString *)argumentString {
+  UILabel *testLabel = [[UILabel alloc] init];
+
+  [testLabel setText:argumentString]; // expected-warning {{String should be localized}}
+}
+
+// [LocalizationTestSuite unLocalizedStringMethod] returns an unlocalized string
+// so we expect an error. Unfrtunately, it probably doesn't make a difference
+// what [LocalizationTestSuite unLocalizedStringMethod] returns since all
+// string values returned are marked as Unlocalized in aggressive reporting.
+- (void)testUnLocalizedStringMethod {
+  UILabel *testLabel = [[UILabel alloc] init];
+  NSString *bar = NSLocalizedString(@"Hello", @"Comment");
+
+  [testLabel setText:[LocalizationTestSuite unLocalizedStringMethod]]; // expected-warning {{String should be localized}}
+}
+
+// This is the reverse situation: accessibilitySetIdentification: doesn't care
+// about localization so we don't expect a warning
+- (void)testMethodNotInRequiresLocalizedStringMethods {
+  UILabel *testLabel = [[UILabel alloc] init];
+
+  [testLabel accessibilitySetIdentification:@"UnlocalizedString"]; // no-warning
+}
+
+// EmptyLocalizationContextChecker tests
+#define HOM(s) YOLOC(s)
+#define YOLOC(x) NSLocalizedString(x, nil)
+
+- (void)testNilLocalizationContext {
+  NSString *string = NSLocalizedString(@"LocalizedString", nil); // expected-warning {{Localized string macro should include a non-empty comment for translators}}
+  NSString *string2 = NSLocalizedString(@"LocalizedString", nil); // expected-warning {{Localized string macro should include a non-empty comment for translators}}
+  NSString *string3 = NSLocalizedString(@"LocalizedString", nil); // expected-warning {{Localized string macro should include a non-empty comment for translators}}
+}
+
+- (void)testEmptyLocalizationContext {
+  NSString *string = NSLocalizedString(@"LocalizedString", @""); // expected-warning {{Localized string macro should include a non-empty comment for translators}}
+  NSString *string2 = NSLocalizedString(@"LocalizedString", @" "); // expected-warning {{Localized string macro should include a non-empty comment for translators}}
+  NSString *string3 = NSLocalizedString(@"LocalizedString", @"	 "); // expected-warning {{Localized string macro should include a non-empty comment for translators}}
+}
+
+- (void)testNSLocalizedStringVariants {
+  NSString *string = NSLocalizedStringFromTable(@"LocalizedString", nil, @""); // expected-warning {{Localized string macro should include a non-empty comment for translators}}
+  NSString *string2 = NSLocalizedStringFromTableInBundle(@"LocalizedString", nil, [[NSBundle alloc] init],@""); // expected-warning {{Localized string macro should include a non-empty comment for translators}}
+  NSString *string3 = NSLocalizedStringWithDefaultValue(@"LocalizedString", nil, [[NSBundle alloc] init], nil,@""); // expected-warning {{Localized string macro should include a non-empty comment for translators}}
+}
+
+- (void)testMacroExpansionNilString {
+  NSString *string = YOLOC(@"Hello"); // expected-warning {{Localized string macro should include a non-empty comment for translators}}
+  NSString *string2 = HOM(@"Hello");  // expected-warning {{Localized string macro should include a non-empty comment for translators}}
+  NSString *string3 = NSLocalizedString((0 ? @"Critical" : @"Current"),nil); // expected-warning {{Localized string macro should include a non-empty comment for translators}}
+}
+
+#define KCLocalizedString(x,comment) NSLocalizedString(x, comment)
+#define POSSIBLE_FALSE_POSITIVE(s,other) KCLocalizedString(s,@"Comment")
+
+- (void)testNoWarningForNilCommentPassedIntoOtherMacro {
+  NSString *string = KCLocalizedString(@"Hello",@""); // no-warning
+  NSString *string2 = KCLocalizedString(@"Hello",nil); // no-warning
+  NSString *string3 = KCLocalizedString(@"Hello",@"Comment"); // no-warning
+}
+
+- (void)testPossibleFalsePositiveSituationAbove {
+  NSString *string = POSSIBLE_FALSE_POSITIVE(@"Hello", nil); // no-warning
+  NSString *string2 = POSSIBLE_FALSE_POSITIVE(@"Hello", @"Hello"); // no-warning
+}
+
+@end

test/Analysis/localization.m

+// RUN: %clang_cc1 -analyze -fblocks -analyzer-store=region -analyzer-checker=alpha.osx.cocoa.NonLocalizedStringChecker -analyzer-checker=alpha.osx.cocoa.EmptyLocalizationContextChecker -verify  %s
+
+// The larger set of tests in located in localization.m. These are tests
+// specific for non-aggressive reporting.
+
+// These declarations were reduced using Delta-Debugging from Foundation.h
+// on Mac OS X.
+
+#define nil ((id)0)
+#define NSLocalizedString(key, comment)                                        \
+  [[NSBundle mainBundle] localizedStringForKey:(key) value:@"" table:nil]
+#define NSLocalizedStringFromTable(key, tbl, comment)                          \
+  [[NSBundle mainBundle] localizedStringForKey:(key) value:@"" table:(tbl)]
+#define NSLocalizedStringFromTableInBundle(key, tbl, bundle, comment)          \
+  [bundle localizedStringForKey:(key) value:@"" table:(tbl)]
+#define NSLocalizedStringWithDefaultValue(key, tbl, bundle, val, comment)      \
+  [bundle localizedStringForKey:(key) value:(val) table:(tbl)]
+@interface NSObject
++ (id)alloc;
+- (id)init;
+@end
+@interface NSString : NSObject
+@end
+@interface NSBundle : NSObject
++ (NSBundle *)mainBundle;
+- (NSString *)localizedStringForKey:(NSString *)key
+                              value:(NSString *)value
+                              table:(NSString *)tableName;
+@end
+@interface UILabel : NSObject
+@property(nullable, nonatomic, copy) NSString *text;
+@end
+@interface TestObject : NSObject
+@property(strong) NSString *text;
+@end
+
+@interface LocalizationTestSuite : NSObject
+int random();
+@end
+
+// Test cases begin here
+@implementation LocalizationTestSuite
+
+// An object passed in as an parameter's string member
+// should not be considered unlocalized
+- (void)testObjectAsArgument:(TestObject *)argumentObject {
+  UILabel *testLabel = [[UILabel alloc] init];
+
+  [testLabel setText:[argumentObject text]]; // no-warning
+  [testLabel setText:argumentObject.text];   // no-warning
+}
+
+- (void)testLocalizationErrorDetectedOnPathway {
+  UILabel *testLabel = [[UILabel alloc] init];
+  NSString *bar = NSLocalizedString(@"Hello", @"Comment");
+
+  if (random()) {
+    bar = @"Unlocalized string";
+  }
+
+  [testLabel setText:bar]; // expected-warning {{String should be localized}}
+}
+
+- (void)testOneCharacterStringsDoNotGiveAWarning {
+  UILabel *testLabel = [[UILabel alloc] init];
+  NSString *bar = NSLocalizedString(@"Hello", @"Comment");
+
+  if (random()) {
+    bar = @"-";
+  }
+
+  [testLabel setText:bar]; // no-warning
+}
+
+- (void)testOneCharacterUTFStringsDoNotGiveAWarning {
+  UILabel *testLabel = [[UILabel alloc] init];
+  NSString *bar = NSLocalizedString(@"Hello", @"Comment");
+
+  if (random()) {
+    bar = @"\u2014";
+  }
+
+  [testLabel setText:bar]; // no-warning
+}
+
+@end