gnu: twitchy: Switch to pyproject.

* gnu/packages/video.scm (twitchy):
[build-system]: Switch to pyproject-build-system.
[arguments]<#:tests?>: Disable them.
<#:phases>: Improve style, use gepxs, remove trailing #t.
[native-inputs]: Add python-setuptools.

Change-Id: Iff9a112e9ce0f6a9c541780033523aadc53b9d2d
Signed-off-by: Sharlatan Hellseher <sharlatanus@gmail.com>

gnu/packages/video.scm

@@ -3943,6 +3943,9 @@ and custom quantization matrices.")
 from sites like Twitch.tv and pipes them into a video player of choice.")
     (license license:bsd-2)))
 
+;; XXX: This package has not been updated in 6 years, is related to an web
+;; application and is not tested, it's most likely not working, but I haven't
+;; tested it.  Consider removal.
 (define-public twitchy
   (let ((commit "9beb36d80b16662414129693e74fa3a2fd97554e")) ; 3.4 has no tag
     (package
@@ -3956,31 +3959,28 @@ from sites like Twitch.tv and pipes them into a video player of choice.")
                (commit commit)))
          (file-name (git-file-name name version))
          (sha256
-          (base32
-           "0di03h1j9ipp2bbnxxlxz07v87icyg2hmnsr4s7184z5ql8kpzr7"))))
-      (build-system python-build-system)
+          (base32 "0di03h1j9ipp2bbnxxlxz07v87icyg2hmnsr4s7184z5ql8kpzr7"))))
+      (build-system pyproject-build-system)
       (arguments
-       '(#:phases
-         (modify-phases %standard-phases
-           (add-after 'unpack 'patch-paths
-             (lambda* (#:key inputs #:allow-other-keys)
-               (substitute* "twitchy/twitchy_play.py"
-                 (("\"streamlink ")
-                  (string-append "\"" (assoc-ref inputs "streamlink")
-                                 "/bin/streamlink ")))
-               #t))
-           (add-before 'check 'check-setup
-             (lambda _
-               (setenv "HOME" (getcwd)) ;Needs to write to ‘$HOME’.
-               #t))
-           (add-after 'install 'install-rofi-plugin
-             (lambda* (#:key outputs #:allow-other-keys)
-               (install-file "plugins/rofi-twitchy"
-                             (string-append (assoc-ref outputs "out")
-                                            "/bin"))
-               #t)))))
-      (inputs
-       (list python-requests streamlink))
+       (list
+        #:tests? #f                     ; No tests.
+        #:phases
+        #~(modify-phases %standard-phases
+            (add-after 'unpack 'patch-paths
+              (lambda* (#:key inputs #:allow-other-keys)
+                (substitute* "twitchy/twitchy_play.py"
+                  (("\"streamlink ")
+                   (format #f "\"~a "
+                           (search-input-file inputs "/bin/streamlink"))))))
+            (add-before 'check 'check-setup
+              (lambda _
+                (setenv "HOME" (getcwd)))) ;Needs to write to ‘$HOME’.
+            (add-after 'install 'install-rofi-plugin
+              (lambda _
+                (install-file "plugins/rofi-twitchy"
+                              (string-append #$output "/bin")))))))
+      (native-inputs (list python-setuptools))
+      (inputs (list python-requests streamlink))
       (home-page "https://github.com/BasioMeusPuga/twitchy")
       (synopsis "Command-line interface for Twitch.tv")
       (description