"git annex upgrade" has lost track of some of my files.  Most of them have "&" characters.  The others contain "%" characters (I haven't tried the testcase below with "%" however).

Testcase:

    # (With git annex v2)
    mkdir ~/testannex1
    cd ~/testannex1
    git init
    git annex init "testannex1"
    touch '02 - Afternoons & Coffeespoons.mp3'
    touch 'no ampersand.mp3'
    git annex add '02 - Afternoons & Coffeespoons.mp3'
    git annex add 'no ampersand.mp3'
    git commit -m added
    git annex whereis '02 - Afternoons & Coffeespoons.mp3'
    git annex whereis 'no ampersand.mp3'
    # (Upgrade git-annex binary to v3 and then...)
    git annex upgrade
    git annex whereis '02 - Afternoons & Coffeespoons.mp3'
    git annex whereis 'no ampersand.mp3'

This produces:

    12:38:40 ~/testannex1 (master)$ git annex whereis '02 - Afternoons & Coffeespoons.mp3'
    whereis 02 - Afternoons & Coffeespoons.mp3 (0 copies) 
    failed
    git-annex: 1 failed
    12:38:40 ~/testannex1 (master)$ git annex whereis 'no ampersand.mp3'
    whereis no ampersand.mp3 (1 copy) 
      	a7b680fc-a8d0-11e0-b0fe-4f94e86d1fb7  -- testannex1 <-- here
    ok

[[!tag done]]