Comment 7 for bug 219406

/usr/share/bash-completion/bash_completion has a bunch of stuff about treating : specially, for completing host:path in scp and similar commands. Spent a bit of time looking at the source of this behaviour, but haven't found it yet.

set -x before pressing tab, and paste that into a file to look at while going through the code seems helpful, but it's slow going.

  There's clearly a bug, though, since either it should return all files in the directory after trying to complete on :, or it should just work.

 You can work around the bug by \quoting the :, though. echo \:<TAB> works fine.