gnu: Add abjad-ext-ipython.

* gnu/packages/music.scm (abjad-ext-ipython): New variable.

Signed-off-by: Efraim Flashner <efraim@flashner.co.il>

gnu/packages/music.scm

@@ -1701,6 +1701,54 @@ and manipulating rhythms such as accelerandi, taleas, and more.")
 music theorist Paul Nauert's quantization grids or Q-Grids, for short.")
     (license license:expat)))
 
+(define-public abjad-ext-ipython
+  (package
+    (name "abjad-ext-ipython")
+    (version "3.3")
+    (source
+     (origin
+       (method git-fetch)
+       (uri (git-reference
+         (url "https://github.com/Abjad/abjad-ext-ipython")
+         (commit (string-append "v" version))))
+       (file-name (git-file-name name version))
+       (sha256
+        (base32
+         "1vv0alpiz0gf5lgjfvlh4km72dvrxfqkwzxl3k4amzci3i0jzbs2"))))
+    (build-system python-build-system)
+    (arguments
+     ;; UnboundLocalError: local variable 'output_path' referenced before assignment
+     `(#:tests? #f
+       #:phases
+       (modify-phases %standard-phases
+         (replace 'check
+           (lambda* (#:key tests? inputs outputs #:allow-other-keys)
+             (when tests?
+               (setenv "HOME" (getcwd))
+               (add-installed-pythonpath inputs outputs)
+               ;; From 'make jupyter-test'
+               (invoke "jupyter" "nbconvert" "--to=html"
+               "--ExecutePreprocessor.enabled=True" "tests/test.ipynb")))))))
+    (native-inputs
+     `(("lilypond" ,lilypond)
+       ("python-black" ,python-black)
+       ("python-flake8" ,python-flake8)
+       ("python-iniconfig" ,python-iniconfig)
+       ("python-isort" ,python-isort)
+       ("python-mypy" ,python-mypy)
+       ("python-pytest" ,python-pytest-6)
+       ("python-pytest-cov" ,python-pytest-cov)
+       ("python-pytest-helpers-namespace" ,python-pytest-helpers-namespace)))
+    (propagated-inputs
+     `(("abjad" ,abjad)
+       ("jupyter" ,jupyter)))
+    (home-page "https://abjad.github.io")
+    (synopsis "Abjad IPython Extension")
+    (description
+     "@code{abjad-ext-ipython} makes it possible to embed music notation in
+@code{jupyter} notebooks.")
+    (license license:expat)))
+
 (define-public non-sequencer
   ;; The latest tagged release is three years old and uses a custom build
   ;; system, so we take the last commit.