From c8928304cfa8d8802d97ba68a3220e68f7ad5d32 Mon Sep 17 00:00:00 2001
From: Maxim Cournoyer <address@hidden>
Date: Sun, 26 Aug 2018 23:58:26 -0400
Subject: [PATCH 3/9] gnu: Add python-black.

* gnu/packages/python.scm (python-black): New variable.
---
 gnu/packages/python.scm | 35 +++++++++++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)

diff --git a/gnu/packages/python.scm b/gnu/packages/python.scm
index fb7f4b35c..e0a990491 100644
--- a/gnu/packages/python.scm
+++ b/gnu/packages/python.scm
@@ -2744,6 +2744,41 @@ which can produce feeds in RSS 2.0, RSS 0.91, and Atom formats.")
 (define-public python2-toml
   (package-with-python2 python-toml))
 
+(define-public python-black
+  (package
+    (name "python-black")
+    (version "18.6b4")
+    (source
+     (origin
+       (method url-fetch)
+       (uri (pypi-uri "black" version))
+       (sha256
+        (base32
+         "0i4sfqgz6w15vd50kbhi7g7rifgqlf8yfr8y78rypd56q64qn592"))))
+    (build-system python-build-system)
+    (arguments
+     `(#:phases
+       (modify-phases %standard-phases
+         (add-after 'patch-source-shebangs 'patch-extra-shebangs
+           (lambda _
+             (let ((python3 (which "python3")))
+               (substitute* '("tests/data/fmtonoff.py"
+                              "tests/data/string_prefixes.py"
+                              "tests/data/function.py")
+                 (("#!/usr/bin/env python3(\\.[0-9]+)?" _ minor-version)
+                  (string-append "#!" python3 (if (string? minor-version)
+                                                  minor-version
+                                                  ""))))))))))
+    (propagated-inputs
+     `(("python-click" ,python-click)
+       ("python-attrs" ,python-attrs)
+       ("python-appdirs" ,python-appdirs)
+       ("python-toml" ,python-toml)))
+    (home-page "https://github.com/ambv/black")
+    (synopsis "The uncompromising code formatter")
+    (description "Black is the uncompromising Python code formatter.")
+    (license license:expat)))
+
 (define-public python-blinker
   (package
     (name "python-blinker")
-- 
2.18.0