Synchronize Folder
Kevin C. Wong -- 20011107 -- v 1.0b6
Synchronize destination folder to match source folder.

20011107 1.0b6
  -- Now requires Mac OS X 10.1 which has many AppleScript fixes and enhancements.
  -- Don't use "info for" since 10.1 fixed the problems "info for" worked around.
  -- Removed copy invisible option because you need to get it from properties which also returns file size.
  -- Removed addIsFolderAttribute() because we don't use it anymore.
  -- Verbose logging of copy decisions.
  -- Use sort of depth-first folder traversal instead of level-order folder traversal.
  -- Do sync delete for each folder right after sync copy of folder.
  -- Choose file name now returns <>. Change to check for m_log_file is not boolean.
  -- Use creation date instead of modification date for Apps, since mod date is not preserved by Finder copy.
  -- Finer logging control: choose from list of five attributes to log.

20011028 1.0b5
  -- Add: m_diff_sec so that modification dates can differ by a few seconds. Default to 60.
  -- Add: m_filter_files so that certain files can be skipped. Default to system files.
  -- Add: m_copy_invisible so that invisible files can be skipped. Default to false.
  -- Add: m_verbose_logging prints every file being checked.
  -- Bug: Trying to copy folder items if destination folder wasn't created because file name is illegal.
  -- Add: m_error_logging for suppressing error and filter logging.

20011026 1.0b4
  -- Use "list folder" instead of "get items of folder alias". Then use file specifications instead of
     actual files, use "info for " to get most if item info we need. These changes
     work with applications and invisible items, which didn't work with "get items of folder alias".
     Lots of little changes to support the new mechanism.

20011025 1.0b3
  -- Bug: No date by comparison if m_copy_newer_files_only is false
  -- Fix: Delete or move non-folder file before we create folder to replace it.
  -- Fix: Close m_log_file when done.
  -- Fix: Close m_log_file before opening it again in case it's already open.
  -- Fix: Test for log write should be "class of m_log_file is file specification".
  -- Fix: Start writing to log file at the end of the file, not the beginning.
  -- Fix: Added line endings to log output.
  -- Workaround: Skip Application files.

This is the latest version of my Synchronize Folder AppleScript (not Folders because it only does it one-way). Beta 5 added filters so it wouldn't try to copy every file, especially weird Finder files that are irrelevant. It also added some logging options so I could see each file being checked, which made me realize that Beta 4's "info for" usage is very slow because it returns the folder size. If you have a couple thousand files in a folder, over a network share it does take a long time to calculate it. My first thought was to use the old "get item" method and do a fallback to "info for" for Applications and a couple of other file types that failed.

Luckily, I waited until Beta 6 and Mac OS X 10.1 to implement that. Mac OS X 10.1 fixes a bunch of things, such as you can now "get item" and retrieve an Application and get attributes from it without erroring. Unfortunately, a bunch of other things broke (e.g. "choose file name" now returns an actual file instead of a file specification) which I spent some time fixing. The upshot of which is that Beta 6 and onwards no longer supports Mac OS X 10.0.

Beta 6 goes back to the Beta 3 roots, using "get item" instead of "info for", which is much faster since I don't need to know file sizes. I still use "list folder" because that returns invisible files and file extensions that the Finder filters out occasionally. I also added more log settings because some settings are only really useful if you're running the script with Script Editor and have the Event Log open. This way I can just output the info that I want -- I think that Event Log crashes Script Editor if it gets too long, though I thought those memory limitations were removed in Mac OS X.

One big change was to make folder traversal depth-first instead of level order. Depth first means that if you quit the script in the middle of its run, you can restart from the last folder it was working on, knowing that previous folders are sync-ed up correctly (note that you don't have the ability to choose certain folders to copy, yet). With level order if you stop in the middle, every subfolder is sync-ed up a little so you have to start all over. Depth first order also requires doing the delete sync portion per folder, as soon as each folder is done. The bonus is that we eliminate the duplicate folder traversal code so the code is not as large as it could have been.

I still haven't done a big test with Beta 6 -- I'll do that tonight. So there may be a few errors will I will fix in Beta 7. Beta 7 will also include other minor code changes to take care of some weird files that seem to be copied every time I run the AppleScript, even though the files haven't changed (or at least I don't think they've changed). That leaves Beta 8 for feature enhancements: create a Deleted Items hierarchy so that if you choose the move option, the files are preserved in context; also save the current settings in properties so that you don't have to reinput them constantly, maybe tie it in to an auto-run option that doesn't ask for user input.