bug#42537: 28.0.50; wdired-test-bug34915 test failing on macOS

[Philipp <p.stephani2@gmail.com>]

This is yet another follow-up tp bug#30700, reporting each failing test
case individually.

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Test wdired-test-bug34915 backtrace:
  signal(ert-test-failed (((should (equal dir (pop names))) :form (equ
  ert-fail(((should (equal dir (pop names))) :form (equal "bar@" "wbar
  #f(compiled-function () #<bytecode 0xdfa3f2ccdbd9c18>)()
  ert--run-test-internal(#s(ert--test-execution-info :test #s(ert-test
  ert-run-test(#s(ert-test :name wdired-test-bug34915 :documentation "
  ert-run-or-rerun-test(#s(ert--stats :selector (not (or ... ...)) :te
  ert-run-tests((not (or (tag :expensive-test) (tag :unstable))) #f(co
  ert-run-tests-batch((not (or (tag :expensive-test) (tag :unstable)))
  ert-run-tests-batch-and-exit((not (or (tag :expensive-test) (tag :un
  eval((ert-run-tests-batch-and-exit '(not (or (tag :expensive-test) (
  command-line-1(("-L" ":." "-l" "ert" "-l" "lisp/wdired-tests" "--eva
  command-line()
  normal-top-level()
Test wdired-test-bug34915 condition:
    (ert-test-failed
     ((should
       (equal dir
	      (pop names)))
      :form
      (equal "bar@" "wbar@")
      :value nil :explanation
      (arrays-of-different-length 4 5 "bar@" "wbar@" first-mismatch-at 0)))
   FAILED  3/5  wdired-test-bug34915 (0.353864 sec)

(Crystal ball says this might be related to macOS filename
normalization/case-insensitivity.)


In GNU Emacs 28.0.50 (build 67, x86_64-apple-darwin19.5.0, NS appkit-1894.50 Version 10.15.5 (Build 19F101))
 of 2020-07-25
Repository revision: 3b44829823f43d3736b8ec9db2258eeff7f6c16a
Repository branch: master
Windowing system distributor 'Apple', version 10.3.1894
System Description:  Mac OS X 10.15.5

Recent messages:
For information about GNU Emacs and the GNU system, type C-h C-a.

Configured using:
 'configure --with-modules --without-xml2 --without-pop --with-mailutils
 --enable-gcc-warnings=warn-only --enable-checking=all
 --enable-check-lisp-object-type 'CFLAGS=-ggdb3 -O0''

Configured features:
JPEG TIFF GIF PNG NOTIFY KQUEUE ACL GNUTLS ZLIB TOOLKIT_SCROLL_BARS NS
MODULES THREADS JSON PDUMPER LCMS2

Important settings:
  value of $LANG: de_DE.UTF-8
  locale-coding-system: utf-8-unix

Major mode: Lisp Interaction

Minor modes in effect:
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  global-eldoc-mode: t
  eldoc-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t
  line-number-mode: t
  transient-mark-mode: t

Load-path shadows:
None found.

Features:
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mml easymenu mml-sec epa epg epg-config gnus-util rmail rmail-loaddefs
text-property-search time-date mm-decode mm-bodies mm-encode mail-parse
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ietf-drums mm-util mail-prsvr mail-utils phst skeleton derived edmacro
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text-properties overlay sha1 md5 base64 format env code-pages mule
custom widget hashtable-print-readable backquote threads kqueue cocoa ns
lcms2 multi-tty make-network-process emacs)

Memory information:
((conses 16 69709 6701)
 (symbols 48 8650 1)
 (strings 32 23543 1226)
 (string-bytes 1 768591)
 (vectors 16 14147)
 (vector-slots 8 172535 9084)
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