Use new ERT `skip-when` macro in tests

* test/lisp/autorevert-tests.el
(auto-revert-test02-auto-revert-deleted-file):
* test/lisp/emacs-lisp/benchmark-tests.el (benchmark-tests):
* test/lisp/emacs-lisp/find-func-tests.el
(find-func-tests--library-completion):
* test/lisp/eshell/esh-proc-tests.el
(esh-proc-test/kill-pipeline):
* test/lisp/filenotify-tests.el (file-notify-test11-symlinks):
* test/lisp/ibuffer-tests.el (ibuffer-0autoload):
* test/lisp/international/ucs-normalize-tests.el
(ucs-normalize-part1):
* test/lisp/net/network-stream-tests.el (echo-server-nowait)
(connect-to-tls-ipv4-nowait, connect-to-tls-ipv6-nowait)
(open-network-stream-tls-wait, open-network-stream-tls-nowait)
(open-network-stream-tls, open-network-stream-tls-nocert)
(open-gnutls-stream-new-api-nowait)
(open-gnutls-stream-old-api-nowait):
* test/lisp/progmodes/cperl-mode-tests.el (cperl-test-bug-10483)
(cperl-test-hyperactive-electric-else):
* test/lisp/progmodes/elisp-mode-tests.el
(eval-last-sexp-print-format-sym-echo)
(eval-last-sexp-print-format-small-int-echo)
(eval-last-sexp-print-format-large-int-echo)
(eval-defun-prints-edebug-when-instrumented):
* test/lisp/progmodes/python-tests.el (python-ffap-module-path-1):
* test/lisp/shadowfile-tests.el (shadow-test00-clusters)
(shadow-test01-sites, shadow-test02-files)
(shadow-test03-expand-cluster-in-file-name)
(shadow-test04-contract-file-name, shadow-test05-file-match)
(shadow-test06-literal-groups, shadow-test07-regexp-groups)
(shadow-test08-shadow-todo, shadow-test09-shadow-copy-files):
* test/lisp/simple-tests.el
(eval-expression-print-format-sym-echo)
(eval-expression-print-format-small-int-echo)
(eval-expression-print-format-large-int-echo):
* test/lisp/term-tests.el (term-simple-lines)
(term-carriage-return, term-line-wrap, term-colors)
(term-colors-bold-is-bright, term-cursor-movement)
(term-scrolling-region, term-set-directory)
(term-line-wrapping-then-motion, term-to-margin):
* test/lisp/thread-tests.el
(thread-tests-list-threads-error-when-not-configured):
* test/lisp/vc/vc-tests.el (backend):
* test/manual/scroll-tests.el (scroll-tests-scroll-margin-0)
(scroll-tests-scroll-margin-negative)
(scroll-tests-scroll-margin-max)
(scroll-tests-scroll-margin-over-max)
(scroll-tests-scroll-margin-whole-window):
* test/misc/test-custom-libs.el (test-custom-libs):
* test/src/emacs-module-tests.el (module/async-pipe):
* test/src/fileio-tests.el (fileio-tests--odd-symlink-chars):
* test/src/filelock-tests.el (filelock-tests-lock-spoiled)
(filelock-tests-file-locked-p-spoiled)
(filelock-tests-unlock-spoiled)
(filelock-tests-kill-buffer-spoiled)
(filelock-tests-detect-external-change):
* test/src/image-tests.el
(image-tests-image-size/error-on-nongraphical-display)
(image-tests-image-mask-p/error-on-nongraphical-display)
(image-tests-image-metadata/error-on-nongraphical-display):
* test/src/process-tests.el (make-process/mix-stderr)
(process-tests/fd-setsize-no-crash/make-network-process)
(process-tests/fd-setsize-no-crash/make-serial-process):
Use ERT `skip-when` macro in tests.

23 files changed, 72 insertions, 72 deletions

diff --git a/test/lisp/autorevert-tests.el b/test/lisp/autorevert-tests.el
index 8dbb5d2a496..e01ce82858b 100644
--- a/test/lisp/autorevert-tests.el
+++ b/test/lisp/autorevert-tests.el
@@ -257,7 +257,7 @@ This expects `auto-revert--messages' to be bound by
   ;; Repeated unpredictable failures, bug#32645.
   :tags '(:unstable)
   ;; Unlikely to be hydra-specific?
-  ;; (skip-unless (not (getenv "EMACS_HYDRA_CI")))
+  ;; (skip-when (getenv "EMACS_HYDRA_CI"))
   (with-auto-revert-test
    (ert-with-temp-file tmpfile
      (let (;; Try to catch bug#32645.
diff --git a/test/lisp/emacs-lisp/benchmark-tests.el b/test/lisp/emacs-lisp/benchmark-tests.el
index 99b5b142c37..7fe3be2157f 100644
--- a/test/lisp/emacs-lisp/benchmark-tests.el
+++ b/test/lisp/emacs-lisp/benchmark-tests.el
@@ -25,8 +25,8 @@
 (ert-deftest benchmark-tests ()
   ;; Avoid fork failures on Cygwin.  See bug#62450 and etc/PROBLEMS
   ;; ("Fork failures in a build with native compilation").
-  (skip-unless (not (and (eq system-type 'cygwin)
-                         (featurep 'native-compile))))
+  (skip-when (and (eq system-type 'cygwin)
+                  (featurep 'native-compile)))
   (let (str t-long t-short m)
     (should (consp (benchmark-run nil (setq m (1+ 0)))))
     (should (consp (benchmark-run 1 (setq m (1+ 0)))))
diff --git a/test/lisp/emacs-lisp/find-func-tests.el b/test/lisp/emacs-lisp/find-func-tests.el
index 7251b76157b..59ecb5ab187 100644
--- a/test/lisp/emacs-lisp/find-func-tests.el
+++ b/test/lisp/emacs-lisp/find-func-tests.el
@@ -32,7 +32,7 @@
 (ert-deftest find-func-tests--library-completion () ;bug#43393
   ;; FIXME: How can we make this work in batch (see also
   ;; `mule-cmds--test-universal-coding-system-argument')?
-  ;; (skip-unless (not noninteractive))
+  ;; (skip-when noninteractive)
   ;; Check that `partial-completion' works when completing library names.
   (should (equal "org/org"
                  (ert-simulate-keys
diff --git a/test/lisp/eshell/esh-proc-tests.el b/test/lisp/eshell/esh-proc-tests.el
index fa20efa71e1..712d3519dce 100644
--- a/test/lisp/eshell/esh-proc-tests.el
+++ b/test/lisp/eshell/esh-proc-tests.el
@@ -281,7 +281,7 @@ prompt.  See bug#54136."
                     (executable-find "sleep")))
   ;; This test doesn't work on EMBA with AOT nativecomp, but works
   ;; fine elsewhere.
-  (skip-unless (not (getenv "EMACS_EMBA_CI")))
+  (skip-when (getenv "EMACS_EMBA_CI"))
   (with-temp-eshell
    (eshell-insert-command
     (concat "sh -c 'while true; do echo y; sleep 1; done' | "
diff --git a/test/lisp/filenotify-tests.el b/test/lisp/filenotify-tests.el
index 0873910ddf9..57099add08b 100644
--- a/test/lisp/filenotify-tests.el
+++ b/test/lisp/filenotify-tests.el
@@ -1583,7 +1583,7 @@ the file watch."
   :tags '(:expensive-test)
   (skip-unless (file-notify--test-local-enabled))
   ;; This test does not work for kqueue (yet).
-  (skip-unless (not (string-equal (file-notify--test-library) "kqueue")))
+  (skip-when (string-equal (file-notify--test-library) "kqueue"))
 
   (setq file-notify--test-tmpfile (file-notify--test-make-temp-name)
         file-notify--test-tmpfile1 (file-notify--test-make-temp-name))
diff --git a/test/lisp/ibuffer-tests.el b/test/lisp/ibuffer-tests.el
index 83bfa1f68af..ec0ba85da39 100644
--- a/test/lisp/ibuffer-tests.el
+++ b/test/lisp/ibuffer-tests.el
@@ -34,7 +34,7 @@
 
 (ert-deftest ibuffer-0autoload ()       ; sort first
   "Tests to see whether ibuffer has been autoloaded"
-  (skip-unless (not (featurep 'ibuf-ext)))
+  (skip-when (featurep 'ibuf-ext))
   (should
    (fboundp 'ibuffer-mark-unsaved-buffers))
   (should
diff --git a/test/lisp/international/ucs-normalize-tests.el b/test/lisp/international/ucs-normalize-tests.el
index 97b8fa66cd3..bc7e743291d 100644
--- a/test/lisp/international/ucs-normalize-tests.el
+++ b/test/lisp/international/ucs-normalize-tests.el
@@ -255,8 +255,8 @@ Must be called with `ucs-normalize-tests--norm-buf' as current buffer."
 
 (ert-deftest ucs-normalize-part1 ()
   :tags '(:expensive-test)
-  (skip-unless (not (or (getenv "EMACS_HYDRA_CI")
-                        (getenv "EMACS_EMBA_CI")))) ; SLOW ~ 1800s
+  (skip-when (or (getenv "EMACS_HYDRA_CI")
+                 (getenv "EMACS_EMBA_CI"))) ; SLOW ~ 1800s
   ;; This takes a long time, so make sure we're compiled.
   (dolist (fun '(ucs-normalize-tests--part1-rule2
                  ucs-normalize-tests--rule1-failing-for-partX
diff --git a/test/lisp/net/network-stream-tests.el b/test/lisp/net/network-stream-tests.el
index 0fd9549c305..8b1ae398930 100644
--- a/test/lisp/net/network-stream-tests.el
+++ b/test/lisp/net/network-stream-tests.el
@@ -236,7 +236,7 @@
     (while (and (eq (process-status proc) 'connect)
                 (< (setq times (1+ times)) 10))
       (sit-for 0.1))
-    (skip-unless (not (eq (process-status proc) 'connect)))
+    (skip-when (eq (process-status proc) 'connect))
     (with-current-buffer (process-buffer proc)
       (process-send-string proc "echo foo")
       (sleep-for 0.1)
@@ -323,7 +323,7 @@
           (while (and (eq (process-status proc) 'connect)
                       (< (setq times (1+ times)) 10))
             (sit-for 0.1))
-          (skip-unless (not (eq (process-status proc) 'connect))))
+          (skip-when (eq (process-status proc) 'connect)))
       (if (process-live-p server) (delete-process server)))
     (setq status (gnutls-peer-status proc))
     (should (consp status))
@@ -336,7 +336,7 @@
 (ert-deftest connect-to-tls-ipv6-nowait ()
   (skip-unless (executable-find "gnutls-serv"))
   (skip-unless (gnutls-available-p))
-  (skip-unless (not (eq system-type 'windows-nt)))
+  (skip-when (eq system-type 'windows-nt))
   (skip-unless (featurep 'make-network-process '(:family ipv6)))
   (let ((server (make-tls-server 44333))
         (times 0)
@@ -368,7 +368,7 @@
           (while (and (eq (process-status proc) 'connect)
                       (< (setq times (1+ times)) 10))
             (sit-for 0.1))
-          (skip-unless (not (eq (process-status proc) 'connect))))
+          (skip-when (eq (process-status proc) 'connect)))
       (if (process-live-p server) (delete-process server)))
     (setq status (gnutls-peer-status proc))
     (should (consp status))
@@ -403,7 +403,7 @@
                       (< (setq times (1+ times)) 10))
             (sit-for 0.1))
           (should proc)
-          (skip-unless (not (eq (process-status proc) 'connect))))
+          (skip-when (eq (process-status proc) 'connect)))
       (if (process-live-p server) (delete-process server)))
     (setq status (gnutls-peer-status proc))
     (should (consp status))
@@ -446,7 +446,7 @@
           (while (and (eq (process-status proc) 'connect)
                       (< (setq times (1+ times)) 10))
             (sit-for 0.1))
-          (skip-unless (not (eq (process-status proc) 'connect))))
+          (skip-when (eq (process-status proc) 'connect)))
       (if (process-live-p server) (delete-process server)))
     (setq status (gnutls-peer-status proc))
     (should (consp status))
@@ -484,7 +484,7 @@
                       (< (setq times (1+ times)) 10))
             (sit-for 0.1))
           (should proc)
-          (skip-unless (not (eq (process-status proc) 'connect))))
+          (skip-when (eq (process-status proc) 'connect)))
       (if (process-live-p server) (delete-process server)))
     (setq status (gnutls-peer-status proc))
     (should (consp status))
@@ -523,7 +523,7 @@
                       (< (setq times (1+ times)) 10))
             (sit-for 0.1))
           (should proc)
-          (skip-unless (not (eq (process-status proc) 'connect))))
+          (skip-when (eq (process-status proc) 'connect)))
       (if (process-live-p server) (delete-process server)))
     (setq status (gnutls-peer-status proc))
     (should (consp status))
@@ -673,7 +673,7 @@
           (while (and (eq (process-status proc) 'connect)
                       (< (setq times (1+ times)) 10))
             (sit-for 0.1))
-          (skip-unless (not (eq (process-status proc) 'connect))))
+          (skip-when (eq (process-status proc) 'connect)))
       (if (process-live-p server) (delete-process server)))
     (setq status (gnutls-peer-status proc))
     (should (consp status))
@@ -712,7 +712,7 @@
           (while (and (eq (process-status proc) 'connect)
                       (< (setq times (1+ times)) 10))
             (sit-for 0.1))
-          (skip-unless (not (eq (process-status proc) 'connect))))
+          (skip-when (eq (process-status proc) 'connect)))
       (if (process-live-p server) (delete-process server)))
     (setq status (gnutls-peer-status proc))
     (should (consp status))
diff --git a/test/lisp/progmodes/cperl-mode-tests.el b/test/lisp/progmodes/cperl-mode-tests.el
index 8f334245c64..87d8ffa2d8d 100644
--- a/test/lisp/progmodes/cperl-mode-tests.el
+++ b/test/lisp/progmodes/cperl-mode-tests.el
@@ -892,8 +892,8 @@ without a statement terminator on the same line does not loop
 forever.  The test starts an asynchronous Emacs batch process
 under timeout control."
   :tags '(:expensive-test)
-  (skip-unless (not (getenv "EMACS_HYDRA_CI"))) ; FIXME times out
-  (skip-unless (not (< emacs-major-version 28))) ; times out in older Emacsen
+  (skip-when (getenv "EMACS_HYDRA_CI")) ; FIXME times out
+  (skip-when (< emacs-major-version 28)) ; times out in older Emacsen
   (skip-unless (eq cperl-test-mode #'cperl-mode))
   (let* ((emacs (concat invocation-directory invocation-name))
          (test-function 'cperl-test--run-bug-10483)
@@ -1242,7 +1242,7 @@ however, must not happen when the keyword occurs in a variable
 \"$else\" or \"$continue\"."
   (skip-unless (eq cperl-test-mode #'cperl-mode))
   ;; `self-insert-command' takes a second argument only since Emacs 27
-  (skip-unless (not (< emacs-major-version 27)))
+  (skip-when (< emacs-major-version 27))
   (with-temp-buffer
     (setq cperl-electric-keywords t)
     (cperl-mode)
diff --git a/test/lisp/progmodes/elisp-mode-tests.el b/test/lisp/progmodes/elisp-mode-tests.el
index 5b6ef88dceb..4fa869c773f 100644
--- a/test/lisp/progmodes/elisp-mode-tests.el
+++ b/test/lisp/progmodes/elisp-mode-tests.el
@@ -128,7 +128,7 @@
 
 (ert-deftest eval-last-sexp-print-format-sym-echo ()
   ;; We can only check the echo area when running interactive.
-  (skip-unless (not noninteractive))
+  (skip-when noninteractive)
   (with-temp-buffer
     (let ((current-prefix-arg nil))
       (erase-buffer) (insert "t") (message nil)
@@ -147,7 +147,7 @@
       (should (equal (buffer-string) "?A65 (#o101, #x41, ?A)")))))
 
 (ert-deftest eval-last-sexp-print-format-small-int-echo ()
-  (skip-unless (not noninteractive))
+  (skip-when noninteractive)
   (with-temp-buffer
     (let ((current-prefix-arg nil))
       (erase-buffer) (insert "?A") (message nil)
@@ -171,7 +171,7 @@
         (should (equal (buffer-string) "?B66 (#o102, #x42, ?B)"))))))
 
 (ert-deftest eval-last-sexp-print-format-large-int-echo ()
-  (skip-unless (not noninteractive))
+  (skip-when noninteractive)
   (with-temp-buffer
     (let ((eval-expression-print-maximum-character ?A))
       (let ((current-prefix-arg nil))
@@ -186,7 +186,7 @@
 ;;; eval-defun
 
 (ert-deftest eval-defun-prints-edebug-when-instrumented ()
-  (skip-unless (not noninteractive))
+  (skip-when noninteractive)
   (with-temp-buffer
     (let ((current-prefix-arg '(4)))
       (erase-buffer) (insert "(defun foo ())") (message nil)
diff --git a/test/lisp/progmodes/python-tests.el b/test/lisp/progmodes/python-tests.el
index 9f935f2748c..a44a11896f0 100644
--- a/test/lisp/progmodes/python-tests.el
+++ b/test/lisp/progmodes/python-tests.el
@@ -4918,7 +4918,7 @@ import abc
   ;; Skip the test on macOS, since the standard Python installation uses
   ;; libedit rather than readline which confuses the running of an inferior
   ;; interpreter in this case (see bug#59477 and bug#25753).
-  (skip-unless (not (eq system-type 'darwin)))
+  (skip-when (eq system-type 'darwin))
   (trace-function 'python-shell-output-filter)
   (python-tests-with-temp-buffer-with-shell
    "
diff --git a/test/lisp/shadowfile-tests.el b/test/lisp/shadowfile-tests.el
index 5edba039032..b1c06ad2d05 100644
--- a/test/lisp/shadowfile-tests.el
+++ b/test/lisp/shadowfile-tests.el
@@ -101,7 +101,7 @@ Per definition, all files are identical on the different hosts of
 a cluster (or site).  This is not tested here; it must be
 guaranteed by the originator of a cluster definition."
   :tags '(:expensive-test)
-  (skip-unless (not (memq system-type '(windows-nt ms-dos))))
+  (skip-when (memq system-type '(windows-nt ms-dos)))
   (skip-unless (file-remote-p ert-remote-temporary-file-directory))
 
   (let ((text-quoting-style 'grave) ;; We inspect the *Messages* buffer!
@@ -219,7 +219,7 @@ guaranteed by the originator of a cluster definition."
 Per definition, all files are identical on the different hosts of
 a cluster (or site).  This is not tested here; it must be
 guaranteed by the originator of a cluster definition."
-  (skip-unless (not (memq system-type '(windows-nt ms-dos))))
+  (skip-when (memq system-type '(windows-nt ms-dos)))
   (skip-unless (file-remote-p ert-remote-temporary-file-directory))
 
   (let ((shadow-info-file shadow-test-info-file)
@@ -320,7 +320,7 @@ guaranteed by the originator of a cluster definition."
 
 (ert-deftest shadow-test02-files ()
   "Check file manipulation functions."
-  (skip-unless (not (memq system-type '(windows-nt ms-dos))))
+  (skip-when (memq system-type '(windows-nt ms-dos)))
   (skip-unless (file-remote-p ert-remote-temporary-file-directory))
 
   (let ((shadow-info-file shadow-test-info-file)
@@ -391,7 +391,7 @@ guaranteed by the originator of a cluster definition."
 
 (ert-deftest shadow-test03-expand-cluster-in-file-name ()
   "Check canonical file name of a cluster or site."
-  (skip-unless (not (memq system-type '(windows-nt ms-dos))))
+  (skip-when (memq system-type '(windows-nt ms-dos)))
   (skip-unless (file-remote-p ert-remote-temporary-file-directory))
 
   (let ((shadow-info-file shadow-test-info-file)
@@ -456,7 +456,7 @@ guaranteed by the originator of a cluster definition."
 
 (ert-deftest shadow-test04-contract-file-name ()
   "Check canonical file name of a cluster or site."
-  (skip-unless (not (memq system-type '(windows-nt ms-dos))))
+  (skip-when (memq system-type '(windows-nt ms-dos)))
   (skip-unless (file-remote-p ert-remote-temporary-file-directory))
 
   (let ((shadow-info-file shadow-test-info-file)
@@ -511,7 +511,7 @@ guaranteed by the originator of a cluster definition."
 
 (ert-deftest shadow-test05-file-match ()
   "Check `shadow-same-site' and `shadow-file-match'."
-  (skip-unless (not (memq system-type '(windows-nt ms-dos))))
+  (skip-when (memq system-type '(windows-nt ms-dos)))
   (skip-unless (file-remote-p ert-remote-temporary-file-directory))
 
   (let ((shadow-info-file shadow-test-info-file)
@@ -563,7 +563,7 @@ guaranteed by the originator of a cluster definition."
 
 (ert-deftest shadow-test06-literal-groups ()
   "Check literal group definitions."
-  (skip-unless (not (memq system-type '(windows-nt ms-dos))))
+  (skip-when (memq system-type '(windows-nt ms-dos)))
   (skip-unless (file-remote-p ert-remote-temporary-file-directory))
 
   (let ((shadow-info-file shadow-test-info-file)
@@ -648,7 +648,7 @@ guaranteed by the originator of a cluster definition."
 
 (ert-deftest shadow-test07-regexp-groups ()
   "Check regexp group definitions."
-  (skip-unless (not (memq system-type '(windows-nt ms-dos))))
+  (skip-when (memq system-type '(windows-nt ms-dos)))
   (skip-unless (file-remote-p ert-remote-temporary-file-directory))
 
   (let ((shadow-info-file shadow-test-info-file)
@@ -710,7 +710,7 @@ guaranteed by the originator of a cluster definition."
 
 (ert-deftest shadow-test08-shadow-todo ()
   "Check that needed shadows are added to todo."
-  (skip-unless (not (memq system-type '(windows-nt ms-dos))))
+  (skip-when (memq system-type '(windows-nt ms-dos)))
   (skip-unless (file-remote-p ert-remote-temporary-file-directory))
   (skip-unless (file-writable-p ert-remote-temporary-file-directory))
 
@@ -855,7 +855,7 @@ guaranteed by the originator of a cluster definition."
 (ert-deftest shadow-test09-shadow-copy-files ()
   "Check that needed shadow files are copied."
   :tags '(:expensive-test)
-  (skip-unless (not (memq system-type '(windows-nt ms-dos))))
+  (skip-when (memq system-type '(windows-nt ms-dos)))
   (skip-unless (file-remote-p ert-remote-temporary-file-directory))
   (skip-unless (file-writable-p ert-remote-temporary-file-directory))
 
diff --git a/test/lisp/simple-tests.el b/test/lisp/simple-tests.el
index 7dabb735522..b632c908443 100644
--- a/test/lisp/simple-tests.el
+++ b/test/lisp/simple-tests.el
@@ -742,7 +742,7 @@ See Bug#21722."
 
 (ert-deftest eval-expression-print-format-sym-echo ()
   ;; We can only check the echo area when running interactive.
-  (skip-unless (not noninteractive))
+  (skip-when noninteractive)
   (with-temp-buffer
     (cl-letf (((symbol-function 'read--expression) (lambda (&rest _) t)))
       (let ((current-prefix-arg nil))
@@ -763,7 +763,7 @@ See Bug#21722."
         (should (equal (buffer-string) "65 (#o101, #x41, ?A)"))))))
 
 (ert-deftest eval-expression-print-format-small-int-echo ()
-  (skip-unless (not noninteractive))
+  (skip-when noninteractive)
   (with-temp-buffer
     (cl-letf (((symbol-function 'read--expression) (lambda (&rest _) ?A)))
       (let ((current-prefix-arg nil))
@@ -789,7 +789,7 @@ See Bug#21722."
         (should (equal (buffer-string) "66 (#o102, #x42, ?B)"))))))
 
 (ert-deftest eval-expression-print-format-large-int-echo ()
-  (skip-unless (not noninteractive))
+  (skip-when noninteractive)
   (with-temp-buffer
     (cl-letf (((symbol-function 'read--expression) (lambda (&rest _) ?B))
               (eval-expression-print-maximum-character ?A))
diff --git a/test/lisp/term-tests.el b/test/lisp/term-tests.el
index ee2bb6574ae..911d03d5628 100644
--- a/test/lisp/term-tests.el
+++ b/test/lisp/term-tests.el
@@ -110,7 +110,7 @@
         (buffer-substring (point-min) (point-max))))))
 
 (ert-deftest term-simple-lines ()
-  (skip-unless (not (memq system-type '(windows-nt ms-dos))))
+  (skip-when (memq system-type '(windows-nt ms-dos)))
   (let ((str "\
 first line\r
 next line\r\n"))
@@ -118,14 +118,14 @@ next line\r\n"))
                    (string-replace "\r" "" str)))))
 
 (ert-deftest term-carriage-return ()
-  (skip-unless (not (memq system-type '(windows-nt ms-dos))))
+  (skip-when (memq system-type '(windows-nt ms-dos)))
   (let ((str "\
 first line\r_next line\r\n"))
     (should (equal (term-test-screen-from-input 40 12 str)
                    "_next line\n"))))
 
 (ert-deftest term-line-wrap ()
-  (skip-unless (not (memq system-type '(windows-nt ms-dos))))
+  (skip-when (memq system-type '(windows-nt ms-dos)))
   (should (string-match-p
            ;; Don't be strict about trailing whitespace.
            "\\`a\\{40\\}\na\\{20\\} *\\'"
@@ -137,7 +137,7 @@ first line\r_next line\r\n"))
                                                 (list str str))))))
 
 (ert-deftest term-colors ()
-  (skip-unless (not (memq system-type '(windows-nt ms-dos))))
+  (skip-when (memq system-type '(windows-nt ms-dos)))
   (pcase-dolist (`(,str ,expected) ansi-test-strings)
     (let ((result (term-test-screen-from-input 40 12 str)))
       (should (equal result expected))
@@ -145,7 +145,7 @@ first line\r_next line\r\n"))
                      (text-properties-at 0 expected))))))
 
 (ert-deftest term-colors-bold-is-bright ()
-  (skip-unless (not (memq system-type '(windows-nt ms-dos))))
+  (skip-when (memq system-type '(windows-nt ms-dos)))
   (let ((ansi-color-bold-is-bright t))
     (pcase-dolist (`(,str ,expected ,bright-expected) ansi-test-strings)
       (let ((expected (or bright-expected expected))
@@ -155,7 +155,7 @@ first line\r_next line\r\n"))
                        (text-properties-at 0 expected)))))))
 
 (ert-deftest term-cursor-movement ()
-  (skip-unless (not (memq system-type '(windows-nt ms-dos))))
+  (skip-when (memq system-type '(windows-nt ms-dos)))
   ;; Absolute positioning.
   (should (equal "ab\ncd"
                  (term-test-screen-from-input
@@ -186,7 +186,7 @@ first line\r_next line\r\n"))
                                 "\e[D\e[Da")))))
 
 (ert-deftest term-scrolling-region ()
-  (skip-unless (not (memq system-type '(windows-nt ms-dos))))
+  (skip-when (memq system-type '(windows-nt ms-dos)))
   (should (equal "\
 line3
 line4
@@ -338,7 +338,7 @@ line6\r
 line7")))))
 
 (ert-deftest term-set-directory ()
-  (skip-unless (not (memq system-type '(windows-nt ms-dos))))
+  (skip-when (memq system-type '(windows-nt ms-dos)))
   (let ((term-ansi-at-user (user-real-login-name)))
     (should (equal (term-test-screen-from-input
                     40 12 "\eAnSiTc /foo/\n" 'default-directory)
@@ -354,7 +354,7 @@ A real-life example is the default zsh prompt which writes spaces
 to the end of line (triggering line-wrapping state), and then
 sends a carriage return followed by another space to overwrite
 the first character of the line."
-  (skip-unless (not (memq system-type '(windows-nt ms-dos))))
+  (skip-when (memq system-type '(windows-nt ms-dos)))
   (let* ((width 10)
          (strs (list "x" (make-string (1- width) ?_)
                      "\r_")))
@@ -364,7 +364,7 @@ the first character of the line."
 (ert-deftest term-to-margin ()
   "Test cursor movement at the scroll margin.
 This is a reduced example from GNU nano's initial screen."
-  (skip-unless (not (memq system-type '(windows-nt ms-dos))))
+  (skip-when (memq system-type '(windows-nt ms-dos)))
   (let* ((width 10)
          (x (make-string width ?x))
          (y (make-string width ?y)))
diff --git a/test/lisp/thread-tests.el b/test/lisp/thread-tests.el
index 4ba7b99719c..5d684a96a18 100644
--- a/test/lisp/thread-tests.el
+++ b/test/lisp/thread-tests.el
@@ -88,7 +88,7 @@
 
 (ert-deftest thread-tests-list-threads-error-when-not-configured ()
   "Signal an error running `list-threads' if threads are not configured."
-  (skip-unless (not (featurep 'threads)))
+  (skip-when (featurep 'threads))
   (should-error (list-threads)))
 
 (provide 'thread-tests)
diff --git a/test/lisp/vc/vc-tests.el b/test/lisp/vc/vc-tests.el
index 0a26e25e32a..f40cee8cc5b 100644
--- a/test/lisp/vc/vc-tests.el
+++ b/test/lisp/vc/vc-tests.el
@@ -781,7 +781,7 @@ This checks also `vc-backend' and `vc-responsible-backend'."
           ;; CVS calls vc-delete-file, which insists on prompting
           ;; "Really want to delete ...?", and `vc-mtn.el' does not implement
           ;; `delete-file' at all.
-          (skip-unless (not (memq ',backend '(CVS Mtn))))
+          (skip-when (memq ',backend '(CVS Mtn)))
           (vc-test--rename-file ',backend))
 
         (ert-deftest
@@ -796,7 +796,7 @@ This checks also `vc-backend' and `vc-responsible-backend'."
                  (format "vc-test-%s01-register" backend-string))))))
           ;; `vc-mtn.el' gives me:
           ;; "Failed (status 1): mtn commit -m Testing vc-version-diff\n\n foo"
-          (skip-unless (not (memq ',backend '(Mtn))))
+          (skip-when (memq ',backend '(Mtn)))
           (vc-test--version-diff ',backend))
         ))))
 
diff --git a/test/manual/scroll-tests.el b/test/manual/scroll-tests.el
index c2a4ef17bff..b2cfeabfe64 100644
--- a/test/manual/scroll-tests.el
+++ b/test/manual/scroll-tests.el
@@ -80,25 +80,25 @@
        ,@body)))
 
 (ert-deftest scroll-tests-scroll-margin-0 ()
-  (skip-unless (not noninteractive))
+  (skip-when noninteractive)
   (scroll-tests-with-buffer-window
     (scroll-tests-up-and-down 0)))
 
 (ert-deftest scroll-tests-scroll-margin-negative ()
   "A negative `scroll-margin' should be the same as 0."
-  (skip-unless (not noninteractive))
+  (skip-when noninteractive)
   (scroll-tests-with-buffer-window
     (scroll-tests-up-and-down -10 0)))
 
 (ert-deftest scroll-tests-scroll-margin-max ()
-  (skip-unless (not noninteractive))
+  (skip-when noninteractive)
   (scroll-tests-with-buffer-window
     (let ((max-margin (/ (window-text-height) 4)))
       (scroll-tests-up-and-down max-margin))))
 
 (ert-deftest scroll-tests-scroll-margin-over-max ()
   "A `scroll-margin' more than max should be the same as max."
-  (skip-unless (not noninteractive))
+  (skip-when noninteractive)
   (scroll-tests-with-buffer-window 7
     (let ((max-margin (/ (window-text-height) 4)))
       (scroll-tests-up-and-down (+ max-margin 1) max-margin)
@@ -155,7 +155,7 @@ middle of the window."
       (should (scroll-tests--point-in-middle-of-window-p)))))
 
 (ert-deftest scroll-tests-scroll-margin-whole-window ()
-  (skip-unless (not noninteractive))
+  (skip-when noninteractive)
   (scroll-tests--scroll-margin-whole-window))
 
 (ert-deftest scroll-tests-scroll-margin-whole-window-line-spacing ()
diff --git a/test/misc/test-custom-libs.el b/test/misc/test-custom-libs.el
index eb565de8eee..d255a87eeaf 100644
--- a/test/misc/test-custom-libs.el
+++ b/test/misc/test-custom-libs.el
@@ -39,7 +39,7 @@
   :tags '(:expensive-test)
   :expected-result :failed ; FIXME: See above.
   ;; This test is very slow, and IMO not worth the time it takes.
-  (skip-unless (not (getenv "EMACS_HYDRA_CI")))
+  (skip-when (getenv "EMACS_HYDRA_CI"))
   (skip-unless (file-readable-p custom-test-admin-cus-test))
   (load custom-test-admin-cus-test)
   (cus-test-libs t)
diff --git a/test/src/emacs-module-tests.el b/test/src/emacs-module-tests.el
index ac88011b543..59af5d9a4a8 100644
--- a/test/src/emacs-module-tests.el
+++ b/test/src/emacs-module-tests.el
@@ -457,7 +457,7 @@ See Bug#36226."
 
 (ert-deftest module/async-pipe ()
   "Check that writing data from another thread works."
-  (skip-unless (not (eq system-type 'windows-nt))) ; FIXME!
+  (skip-when (eq system-type 'windows-nt)) ; FIXME!
   (with-temp-buffer
     (let ((process (make-pipe-process :name "module/async-pipe"
                                       :buffer (current-buffer)
diff --git a/test/src/fileio-tests.el b/test/src/fileio-tests.el
index 50642420ce9..62a9be546f9 100644
--- a/test/src/fileio-tests.el
+++ b/test/src/fileio-tests.el
@@ -50,7 +50,7 @@ Also check that an encoding error can appear in a symlink."
   ;; Some Windows versions don't support symlinks, and those which do
   ;; will pop up UAC elevation prompts, so we disable this test on
   ;; MS-Windows.
-  (skip-unless (not (eq system-type 'windows-nt)))
+  (skip-when (eq system-type 'windows-nt))
   (should (equal nil (fileio-tests--symlink-failure))))
 
 (ert-deftest fileio-tests--directory-file-name ()
diff --git a/test/src/filelock-tests.el b/test/src/filelock-tests.el
index c5e77f70bb2..f4376b2a5b0 100644
--- a/test/src/filelock-tests.el
+++ b/test/src/filelock-tests.el
@@ -109,7 +109,7 @@ the case)."
 
 (ert-deftest filelock-tests-lock-spoiled ()
   "Check `lock-buffer'."
-  (skip-unless (not (eq system-type 'ms-dos))) ; no filelock support
+  (skip-when (eq system-type 'ms-dos)) ; no filelock support
   (filelock-tests--fixture
    (filelock-tests--spoil-lock-file buffer-file-truename)
    ;; FIXME: errors when locking a file are ignored; should they be?
@@ -119,7 +119,7 @@ the case)."
 
 (ert-deftest filelock-tests-file-locked-p-spoiled ()
   "Check that `file-locked-p' fails if the lockfile is \"spoiled\"."
-  (skip-unless (not (eq system-type 'ms-dos))) ; no filelock support
+  (skip-when (eq system-type 'ms-dos)) ; no filelock support
   (filelock-tests--fixture
    (filelock-tests--spoil-lock-file buffer-file-truename)
    (let ((err (should-error (file-locked-p (buffer-file-name)))))
@@ -130,7 +130,7 @@ the case)."
 
 (ert-deftest filelock-tests-unlock-spoiled ()
   "Check that `unlock-buffer' fails if the lockfile is \"spoiled\"."
-  (skip-unless (not (eq system-type 'ms-dos))) ; no filelock support
+  (skip-when (eq system-type 'ms-dos)) ; no filelock support
   (filelock-tests--fixture
    ;; Set the buffer modified with file locking temporarily disabled.
    (let ((create-lockfiles nil))
@@ -150,7 +150,7 @@ the case)."
 
 (ert-deftest filelock-tests-kill-buffer-spoiled ()
   "Check that `kill-buffer' fails if a lockfile is \"spoiled\"."
-  (skip-unless (not (eq system-type 'ms-dos))) ; no filelock support
+  (skip-when (eq system-type 'ms-dos)) ; no filelock support
   (filelock-tests--fixture
    ;; Set the buffer modified with file locking temporarily disabled.
    (let ((create-lockfiles nil))
@@ -176,7 +176,7 @@ the case)."
 
 (ert-deftest filelock-tests-detect-external-change ()
   "Check that an external file modification is reported."
-  (skip-unless (not (eq system-type 'ms-dos))) ; no filelock support
+  (skip-when (eq system-type 'ms-dos)) ; no filelock support
   (skip-unless (executable-find "touch"))
   (skip-unless (executable-find "echo"))
   (dolist (cl '(t nil))
diff --git a/test/src/image-tests.el b/test/src/image-tests.el
index 317f4d3aab6..3eec2bb4c60 100644
--- a/test/src/image-tests.el
+++ b/test/src/image-tests.el
@@ -44,15 +44,15 @@
     (xpm . ,(find-image '((:file "splash.xpm" :type xpm))))))
 
 (ert-deftest image-tests-image-size/error-on-nongraphical-display ()
-  (skip-unless (not (display-images-p)))
+  (skip-when (display-images-p))
   (should-error (image-size 'invalid-spec)))
 
 (ert-deftest image-tests-image-mask-p/error-on-nongraphical-display ()
-  (skip-unless (not (display-images-p)))
+  (skip-when (display-images-p))
   (should-error (image-mask-p (cdr (assq 'xpm image-tests--images)))))
 
 (ert-deftest image-tests-image-metadata/error-on-nongraphical-display ()
-  (skip-unless (not (display-images-p)))
+  (skip-when (display-images-p))
   (should-error (image-metadata (cdr (assq 'xpm image-tests--images)))))
 
 (ert-deftest image-tests-imagemagick-types ()
diff --git a/test/src/process-tests.el b/test/src/process-tests.el
index e17e1c0d833..711a27f1cfb 100644
--- a/test/src/process-tests.el
+++ b/test/src/process-tests.el
@@ -231,7 +231,7 @@ process to complete."
   (with-timeout (60 (ert-fail "Test timed out"))
   ;; Frequent random (?) failures on hydra.nixos.org, with no process output.
   ;; Maybe this test should be tagged unstable?  See bug#31214.
-  (skip-unless (not (getenv "EMACS_HYDRA_CI")))
+  (skip-when (getenv "EMACS_HYDRA_CI"))
   (with-temp-buffer
     (let ((process (make-process
                     :name "mix-stderr"
@@ -723,7 +723,7 @@ FD_SETSIZE file descriptors (Bug#24325)."
   (skip-unless (featurep 'make-network-process '(:server t)))
   (skip-unless (featurep 'make-network-process '(:family local)))
   ;; Avoid hang due to connect/accept handshake on Cygwin (bug#49496).
-  (skip-unless (not (eq system-type 'cygwin)))
+  (skip-when (eq system-type 'cygwin))
   (with-timeout (60 (ert-fail "Test timed out"))
     (ert-with-temp-directory directory
       (process-tests--with-processes processes
@@ -763,7 +763,7 @@ FD_SETSIZE file descriptors (Bug#24325)."
   "Check that Emacs doesn't crash when trying to use more than
 FD_SETSIZE file descriptors (Bug#24325)."
   ;; This test cannot be run if PTYs aren't supported.
-  (skip-unless (not (eq system-type 'windows-nt)))
+  (skip-when (eq system-type 'windows-nt))
   (with-timeout (60 (ert-fail "Test timed out"))
     (process-tests--with-processes processes
       ;; In order to use `make-serial-process', we need to create some