fix error replacing strings in a string, and optimise literal strings a bit

git-svn-id: svn+ssh://svn.gna.org/svn/gnustep/libs/base/trunk@34081 72102866-910b-0410-8b05-ffd578937521

ChangeLog

@@ -1,6 +1,14 @@
+2011-10-28  Richard Frith-Macdonald <rfm@gnu.org>
+
+	* Source/NSString.m: Fix bug when widening mutable string in
+        replaceOccurrencesOfString:...range:
+	* Source/GSString.m: more efficient check to see if a literal string
+	can be converted to ascii or latin1
+
 2011-10-28  Fred Kiefer <FredKiefer@gmx.de>
 
-	* Tests/base/NSMutableString/basic.m: Add test for replaceOccurrencesOfString:...range:
+	* Tests/base/NSMutableString/basic.m: Add test for
+	replaceOccurrencesOfString:...range:
 
 2011-10-27  Richard Frith-Macdonald <rfm@gnu.org>
 

Source/GSString.m

@@ -4996,6 +4996,30 @@ nextUTF8(const uint8_t *p, unsigned l, unsigned *o, unichar *n)
   return 0;
 }
 
+- (BOOL) canBeConvertedToEncoding: (NSStringEncoding)encoding
+{
+  if (NSASCIIStringEncoding == encoding)
+    {
+      BOOL	ascii;
+
+      lengthUTF8((const uint8_t*)nxcsptr, nxcslen, &ascii, 0);
+      return ascii;
+    }
+  else if (NSISOLatin1StringEncoding == encoding)
+    {
+      BOOL	latin1;
+
+      lengthUTF8((const uint8_t*)nxcsptr, nxcslen, 0, &latin1);
+      return latin1;
+    }
+  else
+    {
+      id d = [self dataUsingEncoding: encoding allowLossyConversion: NO];
+
+      return d != nil ? YES : NO;
+    }
+}
+
 - (NSData*) dataUsingEncoding: (NSStringEncoding)encoding
 	 allowLossyConversion: (BOOL)flag
 {

Source/NSString.m

@@ -5524,8 +5524,15 @@ static NSFileManager *fm = nil;
 	      searchRange.location = range.location + byLen;
 	      searchRange.length = newEnd - searchRange.location;
 	    }
-
-	  range = (*func)(self, replace, opts, searchRange);
+	  if (searchRange.length > 0)
+	    {
+	      /* We replaced something and now need to scan again.
+	       * As we modified the receiver, we must refresh the
+	       * method implementation for searching.
+	       */
+	      func = GSPrivateRangeOfString(self, replace);
+	      range = (*func)(self, replace, opts, searchRange);
+	    }
 	}
       while (range.length > 0);
     }