perhaps put the bracket after the $& as a temp solution. But you're right it does look like a bug, since you only get it on $false.
alias testing2 {
if ($true) $&
{ echo -a bug }
}
alias testing {
if ($false) $&
{ echo -a bug }
}
edit: although as you know, you can already split lines after a bracket without the need for $&
alias testing2 {
if ($true) {
echo -a bug }
}
alias testing {
if ($false) {
echo -a bug }
}