[bug#39451] [PATCH] gnu: subversion: Support running the tests in parallel.

[Christopher Baines]

This drops the time to build the package on my machine from ~14 minutes to ~5
minutes.

* gnu/packages/version-control.scm (subversion)[arguments]: Add set-PARALLEL
phase to set the PARALLEL environment variable.
---
 gnu/packages/version-control.scm | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/gnu/packages/version-control.scm b/gnu/packages/version-control.scm
index 20db6b4b08..140eccb7ec 100644
--- a/gnu/packages/version-control.scm
+++ b/gnu/packages/version-control.scm
@@ -1434,6 +1434,10 @@ following features:
              (substitute* "subversion/tests/libsvn_repos/repos-test.c"
                (("#!/bin/sh") (string-append "#!" (which "sh"))))
              #t))
+         (add-before 'check 'set-PARALLEL
+           (lambda _
+             (setenv "PARALLEL" (number->string (parallel-job-count)))
+             #t))
          (add-after 'install 'install-perl-bindings
            (lambda* (#:key outputs #:allow-other-keys)
              ;; Follow the instructions from 
'subversion/bindings/swig/INSTALL'.
-- 
2.25.0