Setup a plugin.
  
    $ mkdir plugin
  
  A git wrapper that works with the plugin's repo.
  
    $ pg () {
    >   git --git-dir plugin/.git --work-tree plugin "$@"
    > }
  
  Setup the plugin repo.
  
    $ pg init
    Initialized empty Git repository in .+?/plugin/\.git/? (re)
  
  Write to the plugin.
  
    $ cat > plugin/aliases.zsh <<EOF
    > alias hehe='echo hehe'
    > EOF
    $ pg add .
    $ pg commit -m 'Initial commit'
    \[master \(root-commit\) [a-f0-9]{7}\] Initial commit (re)
     1 file changed, 1 insertion(+)
     create mode [\d]{6} aliases\.zsh (re)
  
  Load plugin from master.
  
    $ antigen-bundle $PWD/plugin
    Cloning into '.+?'\.\.\. (re)
    done.
    $ hehe
    hehe
  
  Update the plugin.
  
    $ cat > plugin/aliases.zsh <<EOF
    > alias hehe='echo hehe, updated'
    > EOF
    $ pg commit -am 'Updated message'
    \[master [a-f0-9]{7}\] Updated message (re)
     1 file changed, 1 insertion(+), 1 deletion(-)
  
  Update bundles.
  
    $ antigen-update
    From .+?/plugin (re)
       [a-z0-9]{7}\.\.[a-z0-9]{7}  master     -> origin/master (re)
    Updating [a-z0-9]{7}\.\.[a-z0-9]{7} (re)
    Fast-forward
     aliases.zsh |    2 +-
     1 file changed, 1 insertion(+), 1 deletion(-)
  
  Confirm there is still only one repository.
  
    $ ls $ADOTDIR/repos | wc -l
    1
  
  The new alias should not activate.
  
    $ hehe
    hehe