Question

I am trying to write logic test to debug a a method that saves image data to disk. I use the following lines to write image data to the documents directory:

docspath = [[NSString alloc] initWithString:[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, TRUE) objectAtIndex:0]];
fullpath = [[NSString alloc] initWithFormat:@"%@/%@", docspath, _name]; 
BOOL written = [fileData writeToFile:fullpath options:NSDataWritingAtomic error:&dataerror];

Except, the data is not written and the error description returns no such file or directory. I am running this code under a test target in the iOS 5.1 simulator. Do I need to create intermediate directories to get to the documents directory, or is there another issue with writing to disk under a test target?

The error returned:

2012-06-29 16:13:31.819 otest[4597:7b03] /Users/myaccount/xcode_projects/myproject/myproject/myfolder/MMFileManager.m - 285: Error Domain=NSCocoaErrorDomain Code=4 "The operation couldn’t be completed. (Cocoa error 4.)" UserInfo=0x1e1e3a0 {NSUserStringVariant=Folder, NSFilePath=/Users/myaccount/Library/Application Support/iPhone Simulator/5.1/Documents/mmLogo.png, NSUnderlyingError=0x1e1b430 "The operation couldn’t be completed. No such file or directory"}

Answer 1

Unit test is not in your app, therefore, you can’t access Documents directory in the unit test.

refer to NSHomeDirectory in iPhone unit test