From 55548cdc6af701bfa3df51139a9cf8fa3a2fcfa5 Mon Sep 17 00:00:00 2001
From: Danny Milosavljevic <dannym@scratchpost.org>
Date: Wed, 3 Apr 2019 19:00:44 +0200
Subject: [PATCH] gnu: rust: Enable parallel tests starting with 1.26.

* gnu/packages/rust.scm (rust-1.26)[arguments]<#:phases>[check]: Enable
parallel tests.
---
 gnu/packages/rust.scm | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/gnu/packages/rust.scm b/gnu/packages/rust.scm
index 5198fd3328..f3b2d7366b 100644
--- a/gnu/packages/rust.scm
+++ b/gnu/packages/rust.scm
@@ -724,6 +724,16 @@ jemalloc = \"" jemalloc "/lib/libjemalloc_pic.a" "\"
           `(modify-phases ,phases
              ;; binaryen was replaced with LLD project from LLVM
              (delete 'dont-build-native)
+             (replace 'check
+               (lambda* _
+                 ;; Enable parallel execution.
+                 (let ((parallel-job-spec
+                        (string-append "-j" (number->string
+                                             (min 4
+                                                  (parallel-job-count))))))
+                   (invoke "./x.py" parallel-job-spec "test" "-vv")
+                   (invoke "./x.py" parallel-job-spec "test"
+                           "src/tools/cargo"))))
              (replace 'remove-unsupported-tests
                (lambda* _
                  ;; Our ld-wrapper cannot process non-UTF8 bytes in LIBRARY_PATH.