isearch-pre-command-hook
isearch-pre-command-hook is a compiled Lisp function in `isearch.el
'.
(isearch-pre-command-hook)
Decide whether to exit Isearch mode before executing the command.
Don't exit Isearch if the key sequence that invoked this command
is bound in `isearch-mode-map', or if the invoked command is
a prefix argument command (when `isearch-allow-prefix' is non-nil),
or it is a scrolling command (when `isearch-allow-scroll' is non-nil).
Otherwise, exit Isearch (when `search-exit-option' is non-nil)
before the command is executed globally with terminated Isearch.