❌ Checking for failure/success, even up the chain prevents 'set -e' from triggering.❌

To show in an example, how set -e is prevented from triggering if up the chain we have a success or error branch.

Let's say we have the following code.

#!/usr/bin/env bash

set -e

echo_with_pid(){
  echo "[\$\$=$$/$BASHPID] $*"
}

foo2() {
  echo_with_pid "foo2-enter"
  i_dont_exist
  echo_with_pid "foo2-exit"
}

foo1() {
  echo_with_pid "foo1-enter"
  foo2
  echo_with_pid "foo1-exit"
}

main() {
  echo_with_pid "START"
  foo1
  echo_with_pid "DONE"
}

# If we just call main, `set -e` works as one would expect
main

Aborts execution and giving us the following output:

[$$=37290/37290] START
[$$=37290/37290] foo1-enter
[$$=37290/37290] foo2-enter
/tmp/scratch.sh: line 11: i_dont_exist: command not found

BUT, if we were to check the return code of main, the behavior becomes quite un-intuitive.

# If we run with having just a success branch (no failure branch), the not-found command get's masked.
if main; then
  echo "Main succeeded"
fi

❯/tmp/scratch.sh
[$$=38049/38049] START
[$$=38049/38049] foo1-enter
[$$=38049/38049] foo2-enter
/tmp/scratch.sh: line 11: i_dont_exist: command not found
[$$=38049/38049] foo2-exit
[$$=38049/38049] foo1-exit
[$$=38049/38049] DONE
Main succeeded

command_not_found_handle does not have this issue and is able to catch

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