gnu: Add rust-tokio-macros-0.2.

* gnu/packages/crates-io.scm (rust-tokio-macros-0.2): New variable.

gnu/packages/crates-io.scm

@@ -24014,6 +24014,31 @@ the current thread.")
 futures efficiently")
     (license (list license:asl2.0 license:expat))))
 
+(define-public rust-tokio-macros-0.2
+  (package
+    (name "rust-tokio-macros")
+    (version "0.2.5")
+    (source
+     (origin
+       (method url-fetch)
+       (uri (crate-uri "tokio-macros" version))
+       (file-name (string-append name "-" version ".tar.gz"))
+       (sha256
+        (base32 "1283aq0l7rnh79zzqk4r34dgimvwcymrzmg1yah9ai2nmb3arhzh"))))
+    (build-system cargo-build-system)
+    (arguments
+     `(#:tests? #f ;; FIXME tests use bytes-0.5, require Rust >= 1.39
+       #:cargo-inputs
+       (("rust-proc-macro2" ,rust-proc-macro2-1.0)
+        ("rust-quote" ,rust-quote-1.0)
+        ("rust-syn" ,rust-syn-1.0))
+       #:cargo-development-inputs
+       (("rust-tokio" ,rust-tokio-0.2))))
+    (home-page "https://tokio.rs")
+    (synopsis "Tokio's proc macros")
+    (description "This package provides Tokio's proc macros.")
+    (license license:expat)))
+
 (define-public rust-tokio-mock-task-0.1
   (package
     (name "rust-tokio-mock-task")