Attempt to rename file in Documents directory has error "file:/..." - ios

Question

Below is the code I have written to change the name of any file stored in an iOS device "Documents" directory.
When renaming the file using this code, the prefix resolves to...
"file:/localhost/private/var/mobile/Applications/.../Documents/"
instead of the correctly formatted...
"file://localhost/private/var/mobile/Applications/.../Documents/"
I am losing a slash, and so the rename method fails!!!
I have rewritten this for both NSString and NSURL formats, and both methods present the identical error. I have tested this using the iOS Simulator and on device, and both tests present the identical error.
I suspect I am overlooking something simple, but cannot figure what it is - any help please?
- (void)alterFileNameOrExtension {
NSError *errorMove = nil;
NSError __autoreleasing *error = nil;
//note below - entity attribute document.dStringURL has a data type NSString
NSString *file = [document.dStringURL lastPathComponent];
NSString *fileName = [file stringByDeletingPathExtension];
NSString *fileExtension = [file pathExtension];
NSString *fileNameNew = nil;
//note below - self.tempFileComponent, self.tempFileName & self.tempFileExtension
//note below - are set in the (IBAction) method textFieldDidEndEditing:
//note below - self.tempFileComponent determines whether the user is attempting to change the file name or the file extension
if (self.tempFileComponent == 1) {
fileNameNew = [[self.tempFileName stringByAppendingPathExtension:fileExtension] stringByAddingPercentEscapesUsingEncoding:NSASCIIStringEncoding];
} else if (self.tempFileComponent == 2) {
fileNameNew = [fileName stringByAppendingPathExtension:self.tempFileExtension];
} else {
NSLog(#"%# - %# - attempt to determine tempFileComponent has (possible undefined) E~R~R~O~R: %#_", self.className, NSStringFromSelector(_cmd), error.localizedDescription);
}
NSString *filePath = [document.dStringURL stringByDeletingLastPathComponent];
NSString *filePathNew = [filePath stringByAppendingPathComponent:fileNameNew];
BOOL move = [[NSFileManager defaultManager] moveItemAtPath:document.dStringURL toPath:filePathNew error:&errorMove];
if (!move) {
//handle error
} else {
//complete process
}
}
#
With assistance from #Mario, I have adjusted my code and include the working version below for the benefit of others...
#
NSError *errorMove = nil;
NSError __autoreleasing *error = nil;
NSString *file = [document.dStringURL lastPathComponent];
NSString *fileName = [file stringByDeletingPathExtension];
NSString *fileExtension = [file pathExtension];
NSString *fileNameNew = nil;
if (self.tempFileComponent == 1) {
fileNameNew = [self.tempFileName stringByAppendingPathExtension:fileExtension];
} else if (self.tempFileComponent == 2) {
fileNameNew = [fileName stringByAppendingPathExtension:self.tempFileExtension];
} else {
NSLog(#"%# - %# - attempt to determine tempFileComponent has (possible undefined) E~R~R~O~R: %#_", self.className, NSStringFromSelector(_cmd), error.localizedDescription);
}
NSURL *fileURLOld = [NSURL URLWithString:document.dStringURL];
NSURL *fileURLPrefix = [fileURLOld URLByDeletingLastPathComponent];
NSURL *fileURLNew = [fileURLPrefix URLByAppendingPathComponent:fileNameNew];
BOOL move = [[NSFileManager defaultManager] moveItemAtURL:fileURLOld toURL:fileURLNew error:&errorMove];
if (!move) {
//handle error
} else {
//complete process
}

Answer 1

The NSString path manipulation methods like stringByAppendingPathComponent expects file paths not URLs. It will remove double slashes as this is not a valid file path (although it is a valid URL).