gnu: Add rust-send-wrapper-0.6.

* gnu/packages/crates-io.scm (rust-send-wrapper-0.6): New variable.
(rust-send-wrapper-0.5): Inherit from rust-send-wrapper-0.6.

gnu/packages/crates-io.scm

@@ -57571,19 +57571,23 @@ Semantic Versioning.")
          (base32
           "18vhypw6zgccnrlm5ps1pwa0khz7ry927iznpr88b87cagr1v2iq"))))))
 
-(define-public rust-send-wrapper-0.5
+(define-public rust-send-wrapper-0.6
   (package
     (name "rust-send-wrapper")
-    (version "0.5.0")
-    (source
-     (origin
-       (method url-fetch)
-       (uri (crate-uri "send_wrapper" version))
-       (file-name (string-append name "-" version ".tar.gz"))
-       (sha256
-        (base32 "1mwbg1nv36d5kdjb0iwmprz24km0m8ck08dn59gdngqdc77hl34k"))))
+    (version "0.6.0")
+    (source (origin
+              (method url-fetch)
+              (uri (crate-uri "send-wrapper" version))
+              (file-name (string-append name "-" version ".tar.gz"))
+              (sha256
+               (base32
+                "0wrxzsh9fzgkkkms621ydnz8mj30ilyq299a8cf65jn1y72hw2yd"))))
     (build-system cargo-build-system)
-    (arguments `(#:skip-build? #t))
+    (arguments
+     `(#:cargo-inputs (("rust-futures-core" ,rust-futures-core-0.3))
+       #:cargo-development-inputs
+       (("rust-futures-executor" ,rust-futures-executor-0.3)
+        ("rust-futures-util" ,rust-futures-util-0.3))))
     (home-page "https://github.com/thk1/send_wrapper")
     (synopsis "Wrapper moving around non-@code{Send} types between threads")
     (description
@@ -57594,6 +57598,20 @@ also have to make sure that the wrapper is dropped from within the original
 thread.  If any of these constraints is violated, a panic occurs.")
     (license (list license:expat license:asl2.0))))
 
+(define-public rust-send-wrapper-0.5
+  (package
+    (inherit rust-send-wrapper-0.6)
+    (name "rust-send-wrapper")
+    (version "0.5.0")
+    (source
+     (origin
+       (method url-fetch)
+       (uri (crate-uri "send_wrapper" version))
+       (file-name (string-append name "-" version ".tar.gz"))
+       (sha256
+        (base32 "1mwbg1nv36d5kdjb0iwmprz24km0m8ck08dn59gdngqdc77hl34k"))))
+    (arguments `(#:skip-build? #t))))
+
 (define-public rust-send-wrapper-0.4
   (package
     (inherit rust-send-wrapper-0.5)