URL of track in AppleScript fails

[David Kågedal]

There is something wrong with the "URL" property of track objects in AppleScript. Try this in the AppleScript editor:

    tell application "Play"
 first track of library
    end tell

It will result in

    track id 1 of library of application "Play"

which is perfectly fine. This also works:

    title of first track of library

But this causes error -10000:

    URL of first track of library

This is Play Version 0.3 (1071)

[David Kågedal (dkagedal)]

I've been digging through the source and the documentation for various Cocoa APIs (I haven't developed for Mac since System 7 was new and shiny).

I finally managed to see this error reported in the debugger:

2010-01-30 23:40:31.507 Play[19318:80f] An exception was thrown during execution of an NSScriptCommand...
2010-01-30 23:40:31.508 Play[19318:80f] Error while returning the result of a script command: the result object...
file://localhost/Users/david/Music/eMusic/Ambrose%20And%20His%20Orchestra/The%20Hottest%20of%20the%20Decca%20M%20Series/Ambrose%20And%20His%20Orchestra_02_Mean%20to%20Me.mp3
...could not be converted to an Apple event descriptor of type 'text'. This instance of the class 'NSURL' doesn't respond to -scriptingTextDescriptor messages.

What I haven't been able to figure out is where the NSURL appears. The AudioStream has no "url" member, so it seems to come from the database mapping in DatabaseObject. But the SQL defines the url column as "text", and the sdef also declares it as "text". So where is the NSURL created?