Break "NSUTF16" as "NSUTF, 16", not "NSUT, F16".

Previously, this declaration:

  typedef NS_OPTIONS(NSUInteger, NSABitmapFormat5) {
    NSAA16d,
    NSAB32d,
  };

...would import with members .A16d and .B32d, which is not necessarily
correct. (Is it "NS_AA_16d", or "NSA_A_16d"?) Be more conservative here.

Swift SVN r17125

lib/Basic/StringExtras.cpp

@@ -59,7 +59,7 @@ void WordIterator::computeNextPosition() const {
     // If we hit the end of the string, that's it. Otherwise, this
     // word ends at the last uppercase letter, so that the next word
     // starts with the last uppercase letter.
-    NextPosition = i == n? i : i-1;
+    NextPosition = (i == n || !clang::isLowercase(String[i])) ? i : i-1;
     NextPositionValid = true;
     return;
   }
@@ -86,7 +86,7 @@ void WordIterator::computePrevPosition() const {
     // If we hit the beginning of the string, that's it. Otherwise,
     // this word starts at the uppercase letter that terminated the
     // search above.
-    PrevPosition = i == 0 ? 0 : i-1;
+    PrevPosition = (i == 0 || !clang::isLowercase(String[i])) ? i : i-1;
     PrevPositionValid = true;
     return;
   }

lib/ClangImporter/ImportDecl.cpp

@@ -26,6 +26,7 @@
 #include "swift/AST/Stmt.h"
 #include "swift/AST/Types.h"
 #include "swift/ClangImporter/ClangModule.h"
+#include "swift/Parse/Lexer.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/AST/Attr.h"
 #include "clang/AST/DeclVisitor.h"
@@ -319,13 +320,22 @@ static StringRef getCommonWordPrefix(StringRef a, StringRef b) {
   auto aI = aWords.begin(), aE = aWords.end(),
        bI = bWords.begin(), bE = bWords.end();
 
+  unsigned prevLength = 0;
   unsigned prefixLength = 0;
   for ( ; aI != aE && bI != bE; ++aI, ++bI) {
     if (*aI != *bI)
       break;
+
+    prevLength = prefixLength;
     prefixLength = aI.getPosition() + aI->size();
   }
 
+  // Avoid creating a prefix where the rest of the string starts with a number.
+  if ((aI != aE && !Lexer::isIdentifier(*aI)) ||
+      (bI != bE && !Lexer::isIdentifier(*bI))) {
+    prefixLength = prevLength;
+  }
+
   return a.slice(0, prefixLength);
 }
 

test/Inputs/clang-importer-sdk/usr/include/Foundation.h

@@ -245,6 +245,17 @@ typedef NS_OPTIONS(NSUInteger, NSBitmapFormat) {
   NS32BitBigEndianBitmapFormat /*NS_ENUM_AVAILABLE_MAC(10_10)*/ = (1 << 11)
 };
 
+typedef NS_OPTIONS(NSUInteger, NSBitmapFormatReversed) {
+  NS16BitLittleEndianBitmapFormatR /*NS_ENUM_AVAILABLE_MAC(10_10)*/ = (1 << 8),
+  NS32BitLittleEndianBitmapFormatR /*NS_ENUM_AVAILABLE_MAC(10_10)*/ = (1 << 9),
+  NS16BitBigEndianBitmapFormatR /*NS_ENUM_AVAILABLE_MAC(10_10)*/ = (1 << 10),
+  NS32BitBigEndianBitmapFormatR /*NS_ENUM_AVAILABLE_MAC(10_10)*/ = (1 << 11),
+
+  NSAlphaFirstBitmapFormatR            = 1 << 0, // 0 means is alpha last (RGBA, CMYKA, etc.)
+  NSAlphaNonpremultipliedBitmapFormatR = 1 << 1, // 0 means is premultiplied
+  NSFloatingPointSamplesBitmapFormatR  = 1 << 2,	// 0 is integer
+};
+
 typedef NS_OPTIONS(NSUInteger, NSBitmapFormat2) {
   NSU16a,
   NSU32a,
@@ -262,6 +273,11 @@ typedef NS_OPTIONS(NSUInteger, NSUBitmapFormat4) {
   NSU32c,
 };
 
+typedef NS_OPTIONS(NSUInteger, NSABitmapFormat5) {
+  NSAA16d,
+  NSAB32d,
+};
+
 
 @protocol NSWobbling
 -(void)wobble;