Fish shell integration breaks with Fish 2.5.0
Your fish shell integration script breaks with the new version of the fish shell (2.5.0).
function: Illegal function name '-v'
~/.iterm2_shell_integration.fish (line 86): function -v _ underscore_change
if [ x$_ = xfish ]
^
from sourcing file ~/.iterm2_shell_integration.fish
called on line 1 of file ~/.config/fish/config.fish
from sourcing file ~/.config/fish/config.fish
called during startup
the fix is to change line 86 to function underscore_change -v _