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diff --git a/test/lisp/hl-line-tests.el b/test/lisp/hl-line-tests.el
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+++ b/test/lisp/hl-line-tests.el
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+;;; hl-line-tests.el --- Test suite for hl-line. -*- lexical-binding: t -*-
+
+;; Copyright (C) 2022 Free Software Foundation, Inc.
+
+;; This file is part of GNU Emacs.
+
+;; GNU Emacs is free software: you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+
+;; GNU Emacs is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.
+
+;;; Code:
+(require 'ert)
+(require 'hl-line)
+
+(ert-deftest hl-line-sticky ()
+  (should hl-line-sticky-flag)
+  (with-temp-buffer
+    (let ((from-buffer (current-buffer)))
+      (hl-line-mode 1)
+      (save-excursion
+        (insert "foo"))
+      (hl-line-highlight)
+      (should (cl-some (apply-partially #'eq hl-line--overlay)
+                       (overlays-at (point))))
+      (switch-to-buffer (get-buffer-create "*scratch*"))
+      (hl-line-mode 1)
+      (save-excursion
+        (insert "bar"))
+      (hl-line-highlight)
+      (should (cl-some (apply-partially #'eq hl-line--overlay)
+                       (overlays-at (point))))
+      (should (buffer-local-value 'hl-line--overlay from-buffer))
+      (should-not (eq (buffer-local-value 'hl-line--overlay from-buffer)
+                      hl-line--overlay))
+      (customize-set-variable 'hl-line-sticky-flag nil)
+      (should hl-line--overlay)
+      (should (buffer-live-p from-buffer))
+      (should-not (buffer-local-value 'hl-line--overlay from-buffer)))))
+
+(provide 'hl-line-tests)
+
+;;; hl-line-tests.el ends here