When you run Bash under shell in Emacs on macOS then update_terminal_cwd is never defined and after every command you get the error message bash: update_terminal_cwd: command not found making the shell unusable.
The simplest solution is to define update_terminal_cwd when it isn’t defined.
Here is the code:
if [ -z “$(type -t update_terminal_cwd)” ] || [ “$(type -t update_terminal_cwd)” != “function” ]; then
update_terminal_cwd() {
true
}
fi