fix small bug and add optimisation

ChangeLog

@@ -1,3 +1,10 @@
+2024-02-02 Richard Frith-Macdonald <[email protected]>
+
+ Source/NSString.m: Return empty string of correct class when loading
+ from an empty file or URL.
+ Source/Additions/GSMime.m: minor optimisation usng more efficient
+ method to append headers to mutable data object.
+
 2024-02-01 Frederik Seiffert <[email protected]>
 
  * Source/NSLocale.m: Fix -countryCode incorrectly returning language

Source/Additions/GSMime.m

@@ -3544,7 +3544,7 @@ - (void) addToBuffer: (NSMutableData*)buf
  }
  }
  }
- [buf appendData: [self rawMimeDataPreservingCase: YES foldedAt: 0]];
+ [self rawMimeDataPreservingCase: YES foldedAt: 0 to: buf];
  if (masked && *masked)
  {
  NSUInteger len = [buf length];
@@ -7290,7 +7290,7 @@ - (NSMutableData*) rawMimeData: (BOOL)isOuter foldedAt: (NSUInteger)fold
  enumerator = [headers objectEnumerator];
  while ((hdr = [enumerator nextObject]) != nil)
  {
- [md appendData: [hdr rawMimeDataPreservingCase: NO foldedAt: fold]];
+ [hdr rawMimeDataPreservingCase: NO foldedAt: fold to: md];
  }
 
  if (partData != nil)
@@ -8085,7 +8085,7 @@ - (void) encodePart: (GSMimeDocument*)document to: (NSMutableData*)md
  [document setHeader: @"Content-Transfer-Encoding"
  value: enc
  parameters: nil];
- }
+  }
  }
  }
 

Source/NSString.m

@@ -1542,8 +1542,10 @@ - (id) initWithContentsOfFile: (NSString*)path
  if (len == 0)
  {
  RELEASE(d);
- DESTROY(self);
- return @"";
+ return [self initWithBytesNoCopy: (char *)""
+ length: 0
+ encoding: NSASCIIStringEncoding
+ freeWhenDone: NO];
  }
  data_bytes = [d bytes];
  if ((data_bytes != NULL) && (len >= 2))
@@ -1616,8 +1618,10 @@ - (id) initWithContentsOfFile: (NSString*)path
  if (len == 0)
  {
  RELEASE(d);
- DESTROY(self);
- return @"";
+ return [self initWithBytesNoCopy: (char *)""
+ length: 0
+ encoding: NSASCIIStringEncoding
+ freeWhenDone: NO];
  }
  data_bytes = [d bytes];
  if ((data_bytes != NULL) && (len >= 2))
@@ -1668,8 +1672,10 @@ - (id) initWithContentsOfFile: (NSString*)path
  if (len == 0)
  {
  RELEASE(d);
- DESTROY(self);
- return @"";
+ return [self initWithBytesNoCopy: (char *)""
+ length: 0
+ encoding: NSASCIIStringEncoding
+ freeWhenDone: NO];
  }
  self = [self initWithData: d encoding: enc];
  RELEASE(d);
@@ -1719,7 +1725,10 @@ - (id) initWithContentsOfURL: (NSURL*)url
  if (len == 0)
  {
  DESTROY(self);
- return @"";
+ return [self initWithBytesNoCopy: (char *)""
+ length: 0
+ encoding: NSASCIIStringEncoding
+ freeWhenDone: NO];
  }
  data_bytes = [d bytes];
  if ((data_bytes != NULL) && (len >= 2))
@@ -1766,7 +1775,10 @@ - (id) initWithContentsOfURL: (NSURL*)url
  if (len == 0)
  {
  DESTROY(self);
- return @"";
+ return [self initWithBytesNoCopy: (char *)""
+ length: 0
+ encoding: NSASCIIStringEncoding
+ freeWhenDone: NO];
  }
  data_bytes = [d bytes];
  if ((data_bytes != NULL) && (len >= 2))
@@ -1816,7 +1828,10 @@ - (id) initWithContentsOfURL: (NSURL*)url
  if (len == 0)
  {
  DESTROY(self);
- return @"";
+ return [self initWithBytesNoCopy: (char *)""
+ length: 0
+ encoding: NSASCIIStringEncoding
+ freeWhenDone: NO];
  }
  self = [self initWithData: d encoding: enc];
  if (self == nil)