`ffap-gopher-at-point' interminable without newlines

* lisp/ffap.el (ffap-gopher-at-point): Stop when we get to the end
of the buffer.
* test/lisp/ffap-tests.el (ffap-test-no-newlines): Ensure
termination for corner case (bug#44048).

lisp/ffap.el

@@ -1383,7 +1383,8 @@ Sets the variable `ffap-string-at-point-region' to the bounds of URL, if any."
                          (point)))
              (bookmark (cl-loop for keyval = (ffap--gopher-var-on-line)
                                 while keyval collect keyval
-                                do (forward-line 1))))
+                                do (forward-line 1)
+                                until (eobp))))
         (when bookmark
           (setq ffap-string-at-point-region (list beg (point)))
           (let-alist (nconc bookmark '((type . "1") (port . "70")))

test/lisp/ffap-tests.el

@@ -117,6 +117,12 @@ left alone when opening a URL in an external browser."
      t "C:\\temp\\program.log on Windows or /var/log/program.log on Unix.")
     "\\temp\\program.log")))
 
+(ert-deftest ffap-test-no-newlines ()
+  (should-not
+   (with-temp-buffer
+     (save-excursion (insert "type="))
+     (ffap-guess-file-name-at-point))))
+
 (provide 'ffap-tests)
 
 ;;; ffap-tests.el ends here