Why do these rsync filter args fail in bash when passed in array?

Question

Why does this rsync command work when I give it literally but not when I create it from variables?

Here are the variables - first the options I'm passing to rysnc, as an array:

$ echo "${options[@]}"
-av --prune-empty-dirs -f "- *.flac" -f "- *.WMA" -f "- *.wma" -f "- *.ogg" -f "- *.mp4" -f "- *.m4a" -f "- *.webm" -f "- *.wav" -f "- *.ape" -f "- *.zip" -f "- *.rar"

$ echo ${options[6]}
-f

$ echo ${options[7]}
"- *.wma"

Then the source directory, from which rsync is to copy files:

$ echo "\"$dir/\""
"/media/test/Ahmad Jamal Trio/Live at the Pershing/"

And the target directory, to which rsync is to copy files:

$ echo "\"$target_dir\""
"/home/test/mp3/Ahmad Jamal Trio/Live at the Pershing/"

Put it all together:

$ echo "${options[@]}" "\"$dir/\"" "\"$target_dir\""
-av --prune-empty-dirs -f "- *.flac" -f "- *.WMA" -f "- *.wma" -f "- *.ogg" -f "- *.mp4" -f "- *.m4a" -f "- *.webm" -f "- *.wav" -f "- *.ape" -f "- *.zip" -f "- *.rar" "/media/test/Ahmad Jamal Trio/Live at the Pershing//" "/home/test/mp3/Ahmad Jamal Trio/Live at the Pershing/"

That all looks like it should. And indeed, it does work if you give the command literally, like this:

$ rsync -av --prune-empty-dirs -f "- *.flac" -f "- *.WMA" -f "- *.wma" -f "- *.ogg" -f "- *.mp4" -f "- *.m4a" -f "- *.webm" -f "- *.wav" -f "- *.ape" -f "- *.zip" -f "- *.rar" "/media/test/Ahmad Jamal Trio/Live at the Pershing/" "/home/test/mp3/Ahmad Jamal Trio/Live at the Pershing/"
./
Ahmad Jamal Trio - Live at the Pershing - 01 - But Not for Me.mp3
Ahmad Jamal Trio - Live at the Pershing - 02 - Surrey With The Fringe On Top.mp3
Ahmad Jamal Trio - Live at the Pershing - 03 - Moonlight In Vermont.mp3
Ahmad Jamal Trio - Live at the Pershing - 04 - Music, Music, Music.mp3
Ahmad Jamal Trio - Live at the Pershing - 05 - No Greater Love.mp3
Ahmad Jamal Trio - Live at the Pershing - 06 - Poinciana.mp3
Ahmad Jamal Trio - Live at the Pershing - 07 - Wood'yn You.mp3
Ahmad Jamal Trio - Live at the Pershing - 08 - What's New.mp3
AlbumArtSmall.jpg
AlbumArtLarge.jpg
Folder.jpg

sent 43,194,376 bytes  received 285 bytes  28,796,440.67 bytes/sec
total size is 43,182,454  speedup is 1.00

But it fails when I call rsync using the vars as args:

$ rsync "${options[@]}" "\"$dir/\"" "\"$target_dir\""
Unknown filter rule: `"- *.flac"'
rsync error: syntax or usage error (code 1) at exclude.c(902) [client=3.1.2]

Answer 1

Part of your rsync filters and the source and target directories are quoted with additional escaped quotes. Remove the escaped quotes and it should work:

options=(
  -av --prune-empty-dirs 
  -f "- *.flac" 
  -f "- *.WMA" 
  -f "- *.wma" 
  -f "- *.ogg" 
  -f "- *.mp4" 
  -f "- *.m4a" 
  -f "- *.webm" 
  -f "- *.wav" 
  -f "- *.ape" 
  -f "- *.zip" 
  -f "- *.rar"
)
dir="/media/test/Ahmad Jamal Trio/Live at the Pershing"
target_dir="/home/test/mp3/Ahmad Jamal Trio/Live at the Pershing"
rsync "${options[@]}" "$dir/" "$target_dir"

I removed the trailing slashes from the dir and target_dir variables, the / is already added to $dir in the rsync call.