Fall back on CoreFoundation for some core NSString/NSCFString behavio…

…urs (#671)

* Use the _CFString internal methods from ForFoundationOnly in NSCFString.
* Replace our manual strings format parser with CoreFoundation's.
* Check lengths in -isAbsolutePath, -getCharacters:range: and NSCFURL's path code.

*NOTE*: NSString now properly throws range/index exceptions.

Frameworks/CoreFoundationAdditions/_NSCFString.mm

@@ -20,6 +20,11 @@
 #include "_NSCFString.h"
 #include <CoreFoundation/CFString.h>
 
+@interface _NSCFTemporaryRootObject (NSString)
+- (void)_raiseBoundsExceptionForSelector:(SEL)selector andIndex:(NSUInteger)index;
+- (void)_raiseBoundsExceptionForSelector:(SEL)selector andRange:(NSRange)range;
+@end
+
 // ignore bridge cast warnings here. _NSCFString will be a subclass of NSString. It just
 // doesn't realize it yet.
 #pragma clang diagnostic push
@@ -59,19 +64,40 @@ + (instancetype)allocWithZone:(NSZone*)zone {
 
 // NSString overrides
 - (NSUInteger)length {
-    return CFStringGetLength(static_cast<CFStringRef>(self));
+    return _CFStringGetLength2(static_cast<CFStringRef>(self));
+}
+
+- (NSUInteger)hash {
+    return __CFStringHash(static_cast<CFStringRef>(self));
 }
 
 - (unichar)characterAtIndex:(NSUInteger)index {
-    return CFStringGetCharacterAtIndex(static_cast<CFStringRef>(self), index);
+    unichar ch = 0;
+    int err = _CFStringCheckAndGetCharacterAtIndex(static_cast<CFStringRef>(self), index, &ch);
+    if (err == _CFStringErrBounds) {
+        [self _raiseBoundsExceptionForSelector:_cmd andIndex:index];
+        return 0;
+    }
+    return ch;
 }
 
 - (void)getCharacters:(unichar*)buffer range:(NSRange)range {
-    return CFStringGetCharacters(static_cast<CFStringRef>(self), CFRange{ range.location, range.length }, buffer);
+    int err = _CFStringCheckAndGetCharacters(static_cast<CFStringRef>(self), CFRange{ range.location, range.length }, buffer);
+    if (err == _CFStringErrBounds) {
+        [self _raiseBoundsExceptionForSelector:_cmd andRange:range];
+    }
 }
 
 - (void)replaceCharactersInRange:(NSRange)range withString:(NSString*)replacement {
-    CFStringReplace(static_cast<CFMutableStringRef>(self), CFRange{ range.location, range.length }, static_cast<CFStringRef>(replacement));
+    int err = __CFStringCheckAndReplace(static_cast<CFMutableStringRef>(self), CFRange{ range.location, range.length }, static_cast<CFStringRef>(replacement));
+    switch (err) {
+    case _CFStringErrBounds:
+        [self _raiseBoundsExceptionForSelector:_cmd andRange:range];
+        break;
+    case _CFStringErrNotMutable:
+        [self doesNotRecognizeSelector:_cmd];
+        break;
+    }
 }
 
 - (instancetype)copyWithZone:(NSZone*)zone {

Frameworks/CoreFoundationAdditions/_NSCFTemporaryRootObject.mm

@@ -15,5 +15,19 @@
 //******************************************************************************
 #include "_NSCFTemporaryRootObject.h"
 
+#include <Windows.h>
+
 @implementation _NSCFTemporaryRootObject
-@end
+- (void)doesNotRecognizeSelector:(SEL)selector {
+    // According to the reference platform documentation, this method must never return.
+    EXCEPTION_RECORD record{
+        EXCEPTION_NONCONTINUABLE_EXCEPTION,
+        EXCEPTION_NONCONTINUABLE,
+        nullptr,
+        nullptr,
+        0,
+        {0}
+    };
+    RaiseFailFastException(&record, nullptr, FAIL_FAST_GENERATE_EXCEPTION_ADDRESS);
+}
+@end

Frameworks/Foundation/NSCFMutableString.mm

@@ -45,7 +45,7 @@ - (instancetype)initWithUTF8String:(const char*)utf8str {
 
 - (instancetype)initWithFormat:(id)formatStr arguments:(va_list)pReader {
     CFMutableStringRef mutableRef = CFStringCreateMutable(kCFAllocatorDefault, 0);
-    CFStringAppendFormatAndArguments(mutableRef, nullptr, static_cast<CFStringRef>(formatStr), pReader);
+    _CFStringAppendFormatAndArgumentsAux(mutableRef, &_NSCFStringCopyDescription, nullptr, static_cast<CFStringRef>(formatStr), pReader);
     return reinterpret_cast<NSMutableStringPrototype*>(static_cast<NSMutableString*>(mutableRef));
 }
 

Frameworks/Foundation/NSCFString.h

@@ -21,4 +21,6 @@
 @end
 
 @interface NSMutableStringPrototype : NSMutableString
-@end
+@end
+
+CFStringRef _NSCFStringCopyDescription(void* cfTypeRef, const void* locInfo);

Frameworks/Foundation/NSCFString.mm

@@ -23,6 +23,10 @@
 #include "BridgeHelpers.h"
 #include "ForFoundationOnly.h"
 
+CFStringRef _NSCFStringCopyDescription(void* cfTypeRef, const void* locInfo) {
+    return (CFStringRef)[[static_cast<id>(cfTypeRef) description] copy];
+}
+
 @implementation NSStringPrototype
 
 PROTOTYPE_CLASS_REQUIRED_IMPLS(NSObject)
@@ -45,7 +49,7 @@ - (instancetype)initWithUTF8String:(const char*)utf8str {
 
 - (instancetype)initWithFormat:(id)formatStr arguments:(va_list)pReader {
     return reinterpret_cast<NSStringPrototype*>(static_cast<NSString*>(
-        CFStringCreateWithFormatAndArguments(kCFAllocatorDefault, nullptr, static_cast<CFStringRef>(formatStr), pReader)));
+        _CFStringCreateWithFormatAndArgumentsAux(kCFAllocatorDefault, &_NSCFStringCopyDescription, nullptr, static_cast<CFStringRef>(formatStr), pReader)));
 }
 
 - (instancetype)initWithBytes:(const void*)bytes length:(NSUInteger)length encoding:(NSStringEncoding)encoding {
@@ -89,12 +93,12 @@ - (instancetype)initWithFormat:(NSString*)format locale:(id)locale arguments:(va
     CFStringRef str;
 
     if (locale == nil) {
-        str = CFStringCreateWithFormatAndArguments(nullptr, nullptr, static_cast<CFStringRef>(format), argList);
+        str = _CFStringCreateWithFormatAndArgumentsAux(nullptr, &_NSCFStringCopyDescription, nullptr, static_cast<CFStringRef>(format), argList);
     } else if ([locale isKindOfClass:[NSLocale class]] || [locale isKindOfClass:[NSDictionary class]]) {
-        str = CFStringCreateWithFormatAndArguments(kCFAllocatorDefault,
-                                                   static_cast<CFDictionaryRef>(locale),
-                                                   static_cast<CFStringRef>(format),
-                                                   argList);
+        str = _CFStringCreateWithFormatAndArgumentsAux(kCFAllocatorDefault, &_NSCFStringCopyDescription,
+                                                       static_cast<CFDictionaryRef>(locale),
+                                                       static_cast<CFStringRef>(format),
+                                                       argList);
     } else {
         [NSException raise:NSInvalidArgumentException format:@"Locale parameter must be a NSLocale or a NSDictionary."];
     }

Frameworks/Foundation/NSCFURL.mm

@@ -141,7 +141,7 @@ - (NSString*)path {
         ret = [ret stringByRemovingPercentEncoding];
 
         // Remove slashes from before drives
-        if (([ret hasPrefix:_NSGetSlashStr()]) && (_isLetter([ret characterAtIndex:1])) && ([ret characterAtIndex:2] == ':')) {
+        if ([ret length] >= 3 && ([ret hasPrefix:_NSGetSlashStr()]) && (_isLetter([ret characterAtIndex:1])) && ([ret characterAtIndex:2] == ':')) {
             ret = [ret substringFromIndex:1];
         }