gnu: Add cl-s-graphviz.

* gnu/packages/lisp-xyz.scm (cl-s-graphviz, ecl-s-graphviz,
  sbcl-s-graphviz): New variables.

Change-Id: I501e7f48fb3f04380ded5670b522d1ff936d32a4
Signed-off-by: Guillaume Le Vaillant <glv@posteo.net>

gnu/packages/lisp-xyz.scm

@@ -25994,6 +25994,38 @@ (define-public cl-s-base64
 (define-public ecl-s-base64
   (sbcl-package->ecl-package sbcl-s-base64))
 
+(define-public sbcl-s-graphviz
+  (let ((commit "a06d9573f0d4e21751b0ae782515b63a40ad6eae")
+        (revision "1"))
+    (package
+      (name "sbcl-s-graphviz")
+      (version (git-version "2.0" revision commit))
+      (source
+       (origin
+         (method git-fetch)
+         (uri (git-reference
+               (url "https://github.com/jingtaozf/s-graphviz")
+               (commit commit)))
+         (file-name (git-file-name "cl-s-graphviz" version))
+         (sha256
+          (base32 "1841xwci6y1gfhg15464wrlnw8xgsh1mwbg4yy2y7di02q4fbma2"))))
+      (build-system asdf-build-system/sbcl)
+      (inputs
+       (list sbcl-iterate))
+      (native-inputs
+       (list sbcl-literate-lisp))
+      (home-page "https://github.com/jingtaozf/s-graphviz")
+      (synopsis "S-expression representation of the GraphViz DOT language")
+      (description "This package creates GraphViz DOT files from
+an equivalent s-expression representation.")
+      (license license:expat))))
+
+(define-public cl-s-graphviz
+  (sbcl-package->cl-source-package sbcl-s-graphviz))
+
+(define-public ecl-s-graphviz
+  (sbcl-package->ecl-package sbcl-s-graphviz))
+
 (define-public sbcl-s-sysdeps
   ;; No release since 2013.
   (let ((commit "7f8de283b7fbd8b038fdf08493063a736db36ce7")