[swift-users] FileManager.copyItem not throwing?

[Marco S Hyman]

> Running on macOS 10.12.6, Xcode 8.3.2, I get to the copyItem call, which shows an error on the console:
> 
> 2017-11-11 11:18:25.931446+1000 MyApp[32662:2408351] open on /path/to/file: Permission denied
> 
> But it doesn't go to either of my catch blocks, but goes to the following line, where the completion handler is to be run. What is going on?

Known (by Apple) bug.  My report was closed as a duplicate of 30350792.

My workaround is to do this in my do block after attempting to copy a file to saveFileUrl:

    try fileManager.copyItem(at: url, to: saveFileUrl)
    /// DANGER WILL ROBINSON -- the above call can fail to return an
    /// error when the file is not copied.  radar filed and
    /// closed as a DUPLICATE OF 30350792 which is still open.
    /// As a result I must verify that the copied file exists
    if !fileManager.fileExists(atPath: (saveFileUrl.path)) {
        unexpected(error: nil,
                   "Cannot copy \(url.path) to \(saveFileUrl.path)")
        return false
    }

which duplicates what the catch block would do.

Marc