   (with-temp-buffer
     (rust-mode)
     (insert str)
-    (font-lock-ensure)
+    (font-lock-fontify-buffer)
     (buffer-string)))
 
 (defun rust-test-group-str-by-face (str)

1......................500......................50
\"#;
")
    (font-lock-ensure)
    (goto-char 530)
    (insert "#")
    ;; We have now closed the raw string.  Check that the whole string is

(ert-deftest rust-test-two-character-quotes-in-a-row ()
  (with-temp-buffer
    (rust-mode)
    (font-lock-fontify-buffer)
    (insert "'\\n','a', fn")
    (font-lock-after-change-function 1 12 0)

