[bug#44821] [PATCH] gnu: Add diff-so-fancy.

[EuAndreh]

* gnu/packages/version-control.scm (diff-so-fancy): New variable.
---
Now also update copyright notice.

 gnu/packages/version-control.scm | 44 +++++++++++++++++++++++++++++++-
 1 file changed, 43 insertions(+), 1 deletion(-)

diff --git a/gnu/packages/version-control.scm b/gnu/packages/version-control.scm
index 1842528ff6..900f233483 100644
--- a/gnu/packages/version-control.scm
+++ b/gnu/packages/version-control.scm
@@ -14,7 +14,7 @@
 ;;; Copyright © 2017, 2018, 2019, 2020 Tobias Geerinckx-Rice <me@tobias.gr>
 ;;; Copyright © 2017 Vasile Dumitrascu <va511e@yahoo.com>
 ;;; Copyright © 2017 Clément Lassieur <clement@lassieur.org>
-;;; Copyright © 2017 André <eu@euandre.org>
+;;; Copyright © 2017, 2020 EuAndreh <eu@euandre.org>
 ;;; Copyright © 2017, 2018, 2020 Marius Bakke <mbakke@fastmail.com>
 ;;; Copyright © 2017 Stefan Reichör <stefan@xsteve.at>
 ;;; Copyright © 2017, 2020 Oleg Pykhalov <go.wigust@gmail.com>
@@ -55,6 +55,7 @@
   #:use-module (guix git-download)
   #:use-module (guix hg-download)
   #:use-module (guix build-system cmake)
+  #:use-module (guix build-system copy)
   #:use-module (guix build-system gnu)
   #:use-module (guix build-system go)
   #:use-module (guix build-system perl)
@@ -2775,6 +2776,47 @@ for historians.")
     (home-page "https://www.gnu.org/software/gnu-arch/";)
     (license license:gpl2)))                      ;version 2 only
 
+(define-public diff-so-fancy
+  (package
+    (name "diff-so-fancy")
+    (version "1.3.0")
+    (source (origin
+              (method git-fetch)
+              (uri (git-reference
+                    (url "https://github.com/so-fancy/diff-so-fancy";)
+                    (commit (string-append "v" version))))
+              (file-name (git-file-name name version))
+              (sha256
+               (base32
+                "0aavxahzha2mms4vdwysk79pa6wzswpfwgsq2hwaxnaf66maahfl"))))
+    (inputs
+     `(("perl" ,perl)))
+    (propagated-inputs
+     `(("ncurses" ,ncurses)))
+    (build-system copy-build-system)
+    (arguments
+     '(#:phases
+       (modify-phases %standard-phases
+         (add-after 'install 'symlink-executable
+           (lambda* (#:key outputs #:allow-other-keys)
+             (let ((out (assoc-ref outputs "out")))
+               (mkdir (string-append out "/bin"))
+               ;; diff-so-fancy looks for lib/ under the directory
+               ;; it is in
+               (symlink (string-append out "/diff-so-fancy")
+                        (string-append out "/bin/diff-so-fancy"))
+               #t))))
+       #:install-plan
+       '(("lib" "lib")
+         ("diff-so-fancy" "diff-so-fancy"))))
+    (home-page "https://github.com/so-fancy/diff-so-fancy";)
+    (synopsis "Makes diffs more human friendly and readable")
+    (description
+     "@code{diff-so-fancy} strives to make your diffs human readable instead
+of machine readable.  This helps improve code quality and helps you spot
+defects faster.")
+    (license license:expat)))
+
 (define-public go-github-go-git
   (package
     (name "go-github-go-git")
-- 
2.29.2