Add tests for native-compile-prune-cache

* test/lisp/comp-tests.el: New file.

test/lisp/emacs-lisp/comp-tests.el

@@ -0,0 +1,62 @@
+;;; comp-tests.el --- Tests for comp.el  -*- 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/>.
+
+;;; Commentary:
+
+;;; Code:
+
+(require 'ert)
+(require 'ert-x)
+(require 'comp)
+
+(defmacro with-test-native-compile-prune-cache (&rest body)
+  `(ert-with-temp-directory testdir
+     (setq testdir (expand-file-name "eln-cache" testdir))
+     (make-directory testdir)
+     (let* ((c1 (expand-file-name "29.0.50-cur" testdir))
+            (c2 (expand-file-name "29.0.50-old" testdir))
+            (native-comp-eln-load-path (list testdir))
+            (comp-native-version-dir "29.0.50-cur"))
+       (dolist (d (list c1 c2))
+         (make-directory d)
+         (with-temp-file (expand-file-name "some.eln" d) (insert "foo"))
+         (with-temp-file (expand-file-name "some.eln.tmp" d) (insert "foo")))
+       ,@body)))
+
+(ert-deftest test-native-compile-prune-cache ()
+  (skip-unless (featurep 'native-compile))
+  (with-test-native-compile-prune-cache
+   (native-compile-prune-cache)
+   (should (file-directory-p c1))
+   (should (file-regular-p (expand-file-name "some.eln" c1)))
+   (should (file-regular-p (expand-file-name "some.eln.tmp" c1)))
+   (should-not (file-directory-p c2))
+   (should-not (file-regular-p (expand-file-name "some.eln" c2)))
+   (should-not (file-regular-p (expand-file-name "some.eln.tmp" c2)))))
+
+(ert-deftest test-native-compile-prune-cache/delete-only-eln ()
+  (skip-unless (featurep 'native-compile))
+  (with-test-native-compile-prune-cache
+   (with-temp-file (expand-file-name "keep1.txt" c1) (insert "foo"))
+   (with-temp-file (expand-file-name "keep2.txt" c2) (insert "foo"))
+   (native-compile-prune-cache)
+   (should (file-regular-p (expand-file-name "keep1.txt" c1)))
+   (should (file-regular-p (expand-file-name "keep2.txt" c2)))))
+
+;;; comp-tests.el ends here