gnu: Add rust-clap-3.

* gnu/packages/crates-io.scm (rust-clap-3): New variable.
(rust-clap-2): Inherit from above.

Signed-off-by: Nicolas Goaziou <mail@nicolasgoaziou.fr>

gnu/packages/crates-io.scm

@@ -7119,8 +7119,49 @@ traits.")
 derive crate.")
     (license (list license:expat license:asl2.0))))
 
+(define-public rust-clap-3
+  (package
+    (name "rust-clap")
+    (version "3.0.0-beta.2")
+    (source
+     (origin
+       (method url-fetch)
+       (uri (crate-uri "clap" version))
+       (file-name
+        (string-append name "-" version ".tar.gz"))
+       (sha256
+        (base32
+         "0hm1kivw6190rxbfqhdr4hqwlrijvwh90i3d9dyyw0d5k0chdlab"))))
+    (build-system cargo-build-system)
+    (arguments
+     `(#:cargo-inputs
+       (("rust-atty" ,rust-atty-0.2)
+        ("rust-bitflags" ,rust-bitflags-1)
+        ("rust-clap-derive" ,rust-clap-derive-3)
+        ("rust-indexmap" ,rust-indexmap-1)
+        ("rust-os-str-bytes" ,rust-os-str-bytes-2)
+        ("rust-strsim" ,rust-strsim-0.10)
+        ("rust-termcolor" ,rust-termcolor-1)
+        ("rust-terminal-size" ,rust-terminal-size-0.1)
+        ("rust-textwrap" ,rust-textwrap-0.12)
+        ("rust-unicode-width" ,rust-unicode-width-0.1)
+        ("rust-vec-map" ,rust-vec-map-0.8)
+        ("rust-yaml-rust" ,rust-yaml-rust-0.4))
+       #:cargo-development-inputs
+       (("rust-criterion" ,rust-criterion-0.3)
+        ("rust-lazy-static" ,rust-lazy-static-1)
+        ("rust-regex" ,rust-regex-1)
+        ("rust-version-sync" ,rust-version-sync-0.8))))
+    (home-page "https://clap.rs/")
+    (synopsis "Command Line Argument Parser")
+    (description
+     "This package provides a simple to use, efficient, and full-featured
+Command Line Argument Parser.")
+    (license (list license:expat license:asl2.0))))
+
 (define-public rust-clap-2
   (package
+    (inherit rust-clap-3)
     (name "rust-clap")
     (version "2.33.3")
     (source
@@ -7131,7 +7172,6 @@ derive crate.")
        (sha256
         (base32
          "00i065a58987k1sbzqmlz721rw521zcg08jmsh40gi3khp3qmr9p"))))
-    (build-system cargo-build-system)
     (arguments
      `(#:cargo-inputs
        (("rust-ansi-term" ,rust-ansi-term-0.11)
@@ -7148,11 +7188,6 @@ derive crate.")
        (("rust-lazy-static" ,rust-lazy-static-1)
         ("rust-regex" ,rust-regex-1)
         ("rust-version-sync" ,rust-version-sync-0.8))))
-    (home-page "https://clap.rs/")
-    (synopsis "Command Line Argument Parser")
-    (description
-     "This package provides a simple to use, efficient, and full-featured
-Command Line Argument Parser.")
     (license license:expat)))
 
 (define-public rust-clicolors-control-1