dired-tests.el fails on MS-Windows

[Eli Zaretskii <eliz@gnu.org>]

The failed tests are shown below.  2 others failed originally, but I
fixed them.

Tino, please always add comments to the tests explaining the idea
behind all the tricks and juggling.  Otherwise, it is very hard to
understand why the test is doing what it's doing and how it is doing
that.  Same request for ediff-ptch-tests.el, which also fails for me.

Than ks.

dired-tests.log:

  Running 12 tests (2017-08-01 17:44:38+0300)
     passed   1/12  dired-autoload
  Marking matching files...
  Checking d:/gnu/git/emacs/trunk/test/bug22694/test
  1 matching file marked.
     passed   2/12  dired-test-bug22694
  Copy: 1 of 1
  Copy: 1 file
  Copy: 1 of 1
  Copy: 1 file
  Test dired-test-bug25609 backtrace:
    signal(ert-test-failed (((should (file-exists-p target)) :form (file
    ert-fail(((should (file-exists-p target)) :form (file-exists-p "c:/D
    (if (unwind-protect (setq value-17 (apply fn-15 args-16)) (setq form
    (let (form-description-19) (if (unwind-protect (setq value-17 (apply
    (let ((value-17 'ert-form-evaluation-aborted-18)) (let (form-descrip
    (let ((fn-15 (function file-exists-p)) (args-16 (list target))) (let
    (progn (let ((fn-15 (function file-exists-p)) (args-16 (list target)
    (unwind-protect (progn (let ((fn-15 (function file-exists-p)) (args-
    (let* ((from (make-temp-file "foo" 'dir)) (to (make-temp-file "bar" 
    (closure (t) nil (let* ((from (make-temp-file "foo" 'dir)) (to (make
    ert--run-test-internal(#s(ert--test-execution-info :test #s(ert-test
    ert-run-test(#s(ert-test :name dired-test-bug25609 :documentation "T
    ert-run-or-rerun-test(#s(ert--stats :selector t :tests [#s(ert-test 
    ert-run-tests(t #f(compiled-function (event-type &rest event-args) #
    ert-run-tests-batch(nil)
    ert-run-tests-batch-and-exit(nil)
    eval((ert-run-tests-batch-and-exit nil))
    command-line-1(("-L" ";." "-l" "ert" "-l" "lisp/dired-tests.el" "--e
    command-line()
    normal-top-level()
  Test dired-test-bug25609 condition:
      (ert-test-failed
       ((should
	 (file-exists-p target))
	:form
	(file-exists-p "c:/DOCUME~1/Zaretzky/LOCALS~1/Temp/bar6828Ler/foo6828WPJ")
	:value nil))
     FAILED   3/12  dired-test-bug25609
     passed   4/12  dired-test-bug27243-01
     passed   5/12  dired-test-bug27243-02
     passed   6/12  dired-test-bug27243-03
  Test dired-test-bug27631 backtrace:
    signal(error ("em-ls is not a currently loaded feature"))
    error("%s is not a currently loaded feature" "em-ls")
    unload-feature(em-ls force)
    (unwind-protect (progn (make-directory dir1) (make-directory dir2) (
    (let* ((dir (make-temp-file "bug27631" 'dir)) (dir1 (expand-file-nam
    (closure (t) nil (let* ((dir (make-temp-file "bug27631" 'dir)) (dir1
    ert--run-test-internal(#s(ert--test-execution-info :test #s(ert-test
    ert-run-test(#s(ert-test :name dired-test-bug27631 :documentation "T
    ert-run-or-rerun-test(#s(ert--stats :selector t :tests [#s(ert-test 
    ert-run-tests(t #f(compiled-function (event-type &rest event-args) #
    ert-run-tests-batch(nil)
    ert-run-tests-batch-and-exit(nil)
    eval((ert-run-tests-batch-and-exit nil))
    command-line-1(("-L" ";." "-l" "ert" "-l" "lisp/dired-tests.el" "--e
    command-line()
    normal-top-level()
  Test dired-test-bug27631 condition:
      (error "em-ls is not a currently loaded feature")
     FAILED   7/12  dired-test-bug27631
     passed   8/12  dired-test-bug27693
     failed   9/12  dired-test-bug27762
     passed  10/12  dired-test-bug27817
     passed  11/12  dired-test-bug27843
     passed  12/12  dired-test-bug7131

  Ran 12 tests, 10 results as expected, 2 unexpected (2017-08-01 17:44:46+0300)
  1 expected failures

  2 unexpected results:
     FAILED  dired-test-bug25609
     FAILED  dired-test-bug27631

ediff-ptch-tests.log:

  Running 2 tests (2017-08-01 18:21:40+0300)
     passed  1/2  ediff-ptch-test-bug25010
  Test ediff-ptch-test-bug26084 backtrace:
  Test ediff-ptch-test-bug26084 condition:
      (wrong-type-argument stringp nil)
     FAILED  2/2  ediff-ptch-test-bug26084

  Ran 2 tests, 1 results as expected, 1 unexpected (2017-08-01 18:21:40+0300)

  1 unexpected results:
     FAILED  ediff-ptch-test-bug26084