(setq my/setup-functions-alist '((".clang-format" . yaml-mode)))

(defun my/file-setup ()
  (when-let* ((filename (file-name-nondirectory (buffer-file-name)))
              (f (map-elt my/setup-functions-alist filename)))
    (funcall f)))

(add-hook 'find-file-hook #'my/file-setup)