Applescript Finder Selection "Stuck"

I've been using the code below for awhile to auto-magically scale images down through the various wallpaper sizes that I want. This morning, it ceased working and is giving some of the most bizarre behavior I've ever seen.

If I reboot my box, the script works as expected the first time it runs. After that, the previous selection seems to be stuck in the Image Events memory. What I mean is the following:

I have this directory structure:

.
|-- 11
|   `-- Math.png
|-- 1610
|-- 169
|   `-- Math.png
|-- 43
|   `-- Math.png
|-- Math.jpg
`-- Math.png

I run the script for the first time after rebooting with ./169/Math.png selected in the Finder and get the following results in Applescript Editor:

tell application "Finder"
        get selection
                --> {document file "Math.png" of folder "169" of folder "test" of folder "Downloads" of folder "tim" of folder "Users" of startup disk}
        get document file "Math.png" of folder "169" of folder "test" of folder "Downloads" of folder "tim" of folder "Users" of startup disk
                --> alias "Paul:Users:tim:Downloads:test:169:Math.png"
end tell
tell application "Image Events"
        open alias "Paul:Users:tim:Downloads:test:169:Math.png"
                --> image "Math.png"
        get dimensions of image "Math.png"
                --> {2560, 1440}
        scale image "Math.png" to size 1920
        get name of image "Math.png"
                --> "Math.png"
        get name of image "Math.png"
                --> "Math.png"
        offset of "." in "Math.png"
                --> error number -1708
        «event ascrgdut»
                --> error number -1708
        offset of "." in "Math.png"
                --> error number -10004
end tell
tell current application
        offset of "." in "Math.png"
                --> 5
end tell
tell application "Finder"
        get parent of document file "Math.png" of folder "169" of folder "test" of folder "Downloads" of folder "tim" of folder "Users" of startup disk
                --> alias "Paul:Users:tim:Downloads:test:169:"
end tell
tell application "Image Events"
        save image "Math.png" in "/Users/tim/Downloads/test/169/Math_1920x1080.png" as PNG
                --> file "Paul:Users:tim:Downloads:test:169:Math_1920x1080.png"
        scale image "Math.png" to size 1366
        get name of image "Math.png"
                --> "Math.png"
        get name of image "Math.png"
                --> "Math.png"
        offset of "." in "Math.png"
                --> error number -10004
end tell
tell current application
        offset of "." in "Math.png"
                --> 5
end tell
tell application "Finder"
        get parent of document file "Math.png" of folder "169" of folder "test" of folder "Downloads" of folder "tim" of folder "Users" of startup disk
                --> alias "Paul:Users:tim:Downloads:test:169:"
end tell
tell application "Image Events"
        save image "Math.png" in "/Users/tim/Downloads/test/169/Math_1366x768.png" as PNG
                --> file "Paul:Users:tim:Downloads:test:169:Math_1366x768.png"
end tell
Result:
file "Paul:Users:tim:Downloads:test:169:Math_1366x768.png" of application "Image Events"
tell application "Finder"
        get selection
                --> {document file "Math.png" of folder "169" of folder "test" of folder "Downloads" of folder "tim" of folder "Users" of startup disk}
        get document file "Math.png" of folder "169" of folder "test" of folder "Downloads" of folder "tim" of folder "Users" of startup disk
                --> alias "Paul:Users:tim:Downloads:test:169:Math.png"
end tell
tell application "Image Events"
        open alias "Paul:Users:tim:Downloads:test:169:Math.png"
                --> image "Math.png"
        get dimensions of image "Math.png"
                --> {2560, 1440}
        scale image "Math.png" to size 1920
        get name of image "Math.png"
                --> "Math.png"
        get name of image "Math.png"
                --> "Math.png"
        offset of "." in "Math.png"
                --> error number -1708
        «event ascrgdut»
                --> error number -1708
        offset of "." in "Math.png"
                --> error number -10004
end tell
tell current application
        offset of "." in "Math.png"
                --> 5
end tell
tell application "Finder"
        get parent of document file "Math.png" of folder "169" of folder "test" of folder "Downloads" of folder "tim" of folder "Users" of startup disk
                --> alias "Paul:Users:tim:Downloads:test:169:"
end tell
tell application "Image Events"
        save image "Math.png" in "/Users/tim/Downloads/test/169/Math_1920x1080.png" as PNG
                --> file "Paul:Users:tim:Downloads:test:169:Math_1920x1080.png"
        scale image "Math.png" to size 1366
        get name of image "Math.png"
                --> "Math.png"
        get name of image "Math.png"
                --> "Math.png"
        offset of "." in "Math.png"
                --> error number -10004
end tell
tell current application
        offset of "." in "Math.png"
                --> 5
end tell
tell application "Finder"
        get parent of document file "Math.png" of folder "169" of folder "test" of folder "Downloads" of folder "tim" of folder "Users" of startup disk
                --> alias "Paul:Users:tim:Downloads:test:169:"
end tell
tell application "Image Events"
        save image "Math.png" in "/Users/tim/Downloads/test/169/Math_1366x768.png" as PNG
                --> file "Paul:Users:tim:Downloads:test:169:Math_1366x768.png"
end tell
Result:
file "Paul:Users:tim:Downloads:test:169:Math_1366x768.png" of application "Image Events"
tell application "Finder"
        get selection
                --> {document file "Math.png" of folder "169" of folder "test" of folder "Downloads" of folder "tim" of folder "Users" of startup disk}
        get document file "Math.png" of folder "169" of folder "test" of folder "Downloads" of folder "tim" of folder "Users" of startup disk
                --> alias "Paul:Users:tim:Downloads:test:169:Math.png"
end tell
tell application "Image Events"
        open alias "Paul:Users:tim:Downloads:test:169:Math.png"
                --> image "Math.png"
        get dimensions of image "Math.png"
                --> {2560, 1440}
        scale image "Math.png" to size 1920
        get name of image "Math.png"
                --> "Math.png"
        get name of image "Math.png"
                --> "Math.png"
        offset of "." in "Math.png"
                --> error number -1708
        «event ascrgdut»
                --> error number -1708
        offset of "." in "Math.png"
                --> error number -10004
end tell
tell current application
        offset of "." in "Math.png"
                --> 5
end tell
tell application "Finder"
        get parent of document file "Math.png" of folder "169" of folder "test" of folder "Downloads" of folder "tim" of folder "Users" of startup disk
                --> alias "Paul:Users:tim:Downloads:test:169:"
end tell
tell application "Image Events"
        save image "Math.png" in "/Users/tim/Downloads/test/169/Math_1920x1080.png" as PNG
                --> file "Paul:Users:tim:Downloads:test:169:Math_1920x1080.png"
        scale image "Math.png" to size 1366
        get name of image "Math.png"
                --> "Math.png"
        get name of image "Math.png"
                --> "Math.png"
        offset of "." in "Math.png"
                --> error number -10004
end tell
tell current application
tell application "Finder"
        get selection
                --> {document file "Math.png" of folder "169" of folder "test" of folder "Downloads" of folder "tim" of folder "Users" of startup disk}
        get document file "Math.png" of folder "169" of folder "test" of folder "Downloads" of folder "tim" of folder "Users" of startup disk
                --> alias "Paul:Users:tim:Downloads:test:169:Math.png"
end tell
tell application "Image Events"
        open alias "Paul:Users:tim:Downloads:test:169:Math.png"
                --> image "Math.png"
        get dimensions of image "Math.png"
                --> {2560, 1440}
        scale image "Math.png" to size 1920
        get name of image "Math.png"
                --> "Math.png"
        get name of image "Math.png"
             开发者_JAVA百科   --> "Math.png"
        offset of "." in "Math.png"
                --> error number -1708
        «event ascrgdut»
                --> error number -1708
        offset of "." in "Math.png"
                --> error number -10004
end tell
tell current application
        offset of "." in "Math.png"
                --> 5
end tell
tell application "Finder"
        get parent of document file "Math.png" of folder "169" of folder "test" of folder "Downloads" of folder "tim" of folder "Users" of startup disk
                --> alias "Paul:Users:tim:Downloads:test:169:"
end tell
tell application "Image Events"
        save image "Math.png" in "/Users/tim/Downloads/test/169/Math_1920x1080.png" as PNG
                --> file "Paul:Users:tim:Downloads:test:169:Math_1920x1080.png"
        scale image "Math.png" to size 1366
        get name of image "Math.png"
                --> "Math.png"
        get name of image "Math.png"
                --> "Math.png"
        offset of "." in "Math.png"
                --> error number -10004
end tell
tell current application
        offset of "." in "Math.png"
                --> 5
end tell
tell application "Finder"
        get parent of document file "Math.png" of folder "169" of folder "test" of folder "Downloads" of folder "tim" of folder "Users" of startup disk
                --> alias "Paul:Users:tim:Downloads:test:169:"
end tell
tell application "Image Events"
        save image "Math.png" in "/Users/tim/Downloads/test/169/Math_1366x768.png" as PNG
                --> file "Paul:Users:tim:Downloads:test:169:Math_1366x768.png"
end tell
Result:
file "Paul:Users:tim:Downloads:test:169:Math_1366x768.png" of application "Image Events"

I run the script again with ./Math.png selected in Finder:

tell application "Finder"
        get selection
                --> {document file "Math.png" of folder "test" of folder "Downloads" of folder "tim" of folder "Users" of startup disk}
        get document file "Math.png" of folder "test" of folder "Downloads" of folder "tim" of folder "Users" of startup disk
                --> alias "Paul:Users:tim:Downloads:test:Math.png"
end tell
tell application "Image Events"
        open alias "Paul:Users:tim:Downloads:test:Math.png"
                --> image "Math.png"
        get dimensions of image "Math.png"
                --> {2560, 1440}
        scale image "Math.png" to size 1920
        get name of image "Math.png"
                --> "Math.png"
        get name of image "Math.png"
                --> "Math.png"
        offset of "." in "Math.png"
                --> error number -10004
end tell
tell current application
        offset of "." in "Math.png"
                --> 5
end tell
tell application "Finder"
        get parent of document file "Math.png" of folder "test" of folder "Downloads" of folder "tim" of folder "Users" of startup disk
                --> alias "Paul:Users:tim:Downloads:test:"
end tell
tell application "Image Events"
        save image "Math.png" in "/Users/tim/Downloads/test/Math_1920x1080.png" as PNG
                --> file "Paul:Users:tim:Downloads:test:Math_1920x1080.png"
        scale image "Math.png" to size 1366
        get name of image "Math.png"
                --> "Math.png"
        get name of image "Math.png"
                --> "Math.png"
        offset of "." in "Math.png"
                --> error number -10004
end tell
tell current application
        offset of "." in "Math.png"
                --> 5
end tell
tell application "Finder"
        get parent of document file "Math.png" of folder "test" of folder "Downloads" of folder "tim" of folder "Users" of startup disk
                --> alias "Paul:Users:tim:Downloads:test:"
end tell
tell application "Image Events"
        save image "Math.png" in "/Users/tim/Downloads/test/Math_1366x768.png" as PNG
                --> file "Paul:Users:tim:Downloads:test:Math_1366x768.png"
end tell
Result:
file "Paul:Users:tim:Downloads:test:Math_1366x768.png" of application "Image Events"

Notice that the previously selected ./169/Math.png is the one that gets open when I call open currentWallpaper as (alias), despite the fact that the correct wallpaper shows up in the Finder selection. In other words, it's not like Finder is stuck with the old selection, but that the wallpapers that I'm looping through get stuck on the old ones.

Perhaps even more bizarre, is that if I move the old wallpaper, that I had selected, the currentWallpaper reference moves with it! In other words, even if I trash the old selection, the output from the script reports that it's opening the one in ./.Trashes.

It does not seem to get confused as long as the names are different.

The Script:

tell application "Finder" to set wallpapers to selection

set myDimensions to {w169:[{2560, 1440}, {1920, 1080}, {1366, 768}], w1610:[{2560, 1600}, {1920, 1200}, {1440, 900}, {1280, 800}], f43:[{1600, 1200}], s:[{1024, 1024}]}

tell application "Image Events"
    repeat with currentWallpaper in wallpapers
            set theWallpaper to open (currentWallpaper as alias)
            tell theWallpaper
                    set theWallpaperDimensions to dimensions of theWallpaper
                    set currentAspects to {}
                    if my aspectsEqual(16 / 10, theWallpaperDimensions) then set currentAspects to w1610 of myDimensions
                    if my aspectsEqual(16 / 9, theWallpaperDimensions) then set currentAspects to w169 of myDimensions
                    if my aspectsEqual(4 / 3, theWallpaperDimensions) then set currentAspects to f43 of myDimensions
                    if my aspectsEqual(1, theWallpaperDimensions) then set currentAspects to s of myDimensions
                    repeat with dim in currentAspects
                            -- Scale and Crop to current dimensions
                            if item 1 of theWallpaperDimensions is greater than item 1 of dim then
                                    scale to size (get item 1 of dim)

                                    -- Set up save target
                                    set namePrefix to text items 1 thru ((offset of "." in (get name)) - 1) of (get name) as string
                                    tell application "Finder"
                                            set _ to parent of currentWallpaper as alias
                                            set parentPath to POSIX path of _
                                    end tell
                                    set saveTarget to parentPath & namePrefix & "_" & (get item 1 of dim) & "x" & (get item 2 of dim) & ".png"

                                    --save to target
                                    save in saveTarget as PNG
                            end if
                    end repeat
            end tell
    end repeat
end tell

on aspectsEqual(baseAspect, wallpaperDimensions)
    set wallpaperAspect to (item 1 of wallpaperDimensions) / (item 2 of wallpaperDimensions)
    set aspectDifference to baseAspect - wallpaperAspect
    if aspectDifference is less than 0 then set aspectDifference to aspectDifference * -1
    return aspectDifference is less than 1.0E-3
end aspectsEqual

The problem is caused by way "Image Events" returns references to opened images:

open alias "Paul:Users:tim:Downloads:test:Math.png"
        --> image "Math.png"
open alias "Paul:Users:tim:Downloads:test:169:Math.png"
        --> image "Math.png"

The opened image is referenced by name. If you open another image with the same name, the returned reference may occasionally refer to a previously opened image of the same name.

As a work-around add a close every image before you enter the loop that processes the selected images. Furthermore you need to close the opened image when you are done with it:

tell application "Image Events"
    close every image
    repeat with currentWallpaper in wallpapers
        set theWallpaper to open (currentWallpaper as alias)
        tell theWallpaper
        ...
        end tell
        close theWallpaper
    end repeat
end tell