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Save fails after Save As

I have an app with two file types with the following extensions:

gop (an exported type),
sgf (an imported type).

The Save command fails after the following sequence of events:

  1. I open a gop file, say the file "A.gop".
  2. I save this file as an sgf file, say "A.sgf". This Save As works perfectly and the document name in the document’s title bar has changed to "A.sgf".
  3. I change something in the document and then try to Save this change. This should just resave the document to "A.sgf", but "A.sgf" remains untouched. Instead I get a system alert with the message

The document “A.sgf” could not be saved. A file with the name “A.gop” already exists. To save the file, either provide a different name, or move aside or delete the existing file, and try again.

In the Xcode console I get the following diagnostic:

NSFileSandboxingRequestRelatedItemExtension: an error was received from pboxd instead of a token. Domain: NSPOSIXErrorDomain, code: 2 [NSFileCoordinator itemAtURL:willMoveToURL:] could not get a sandbox extension. oldURL: file:///Users/francois/Desktop/A.sgf, newURL: file:///Users/francois/Desktop/A.gop

The problem seems to relate to the sandbox. But I am at a loss to find a solution. (After closing the alert, I check that A.sgf did not register the change.)

If I open an sgf file, say "B.sgf", save it as "B.gop", make a change in the document and then try to save this change (into "B.gop"), I hit the same problem, with "gop" and "sgf" interchanged.

If, instead of saving "A.gop" as "A.sgf", I save it as "B.sgf", make a change in the document and then try to save this change into "B.sgf", I get the following system alert:

The document “B.sgf” could not be saved. You don’t have permission. To view or change permissions, select the item in the Finder and choose File > Get Info.

And in the Xcode console I get the following diagnostic:

NSFileSandboxingRequestRelatedItemExtension: an error was received from pboxd instead of a token. Domain: NSPOSIXErrorDomain, code: 2 [NSFileCoordinator itemAtURL:willMoveToURL:] could not get a sandbox extension. oldURL: file:///Users/francois/Desktop/B.sgf, newURL: file:///Users/francois/Desktop/B.gop

Again the sandbox ! (After closing the alert, I check that B.sgf did not register the change.)

It’s clear my code is missing something, but what?

Save fails after Save As
 
 
Q