01/01: build: ruby: Remove cached gem after install.

[Ricardo Wurmus]

rekado pushed a commit to branch master
in repository guix.

commit 7266848ace1da9b43c3a06bf4c942c56d4ba3d6a
Author: Ben Woodcroft <address@hidden>
Date:   Wed Dec 30 10:27:33 2015 +1000

    build: ruby: Remove cached gem after install.
    
    The .gem file stored in GEM_HOME after install is both redundant and an
    archive that stores timestamped files which makes builds
    non-deterministic, so delete it after 'gem install'.
    
    * guix/build/ruby-build-system.scm (install): Remove cached gem after
      install.
---
 guix/build/ruby-build-system.scm |   19 ++++++++++++-------
 1 files changed, 12 insertions(+), 7 deletions(-)

diff --git a/guix/build/ruby-build-system.scm b/guix/build/ruby-build-system.scm
index 2685da1..6439bf6 100644
--- a/guix/build/ruby-build-system.scm
+++ b/guix/build/ruby-build-system.scm
@@ -1,6 +1,7 @@
 ;;; GNU Guix --- Functional package management for GNU
 ;;; Copyright © 2015 David Thompson <address@hidden>
 ;;; Copyright © 2015 Pjotr Prins <address@hidden>
+;;; Copyright © 2015 Ben Woodcroft <address@hidden>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -115,15 +116,19 @@ GEM-FLAGS are passed to the 'gem' invokation, if present."
                                          (assoc-ref inputs "ruby"))
                            1))
          (out (assoc-ref outputs "out"))
-         (gem-home (string-append out "/lib/ruby/gems/" ruby-version ".0")))
-
+         (gem-home (string-append out "/lib/ruby/gems/" ruby-version ".0"))
+         (gem-name (first-matching-file "\\.gem$")))
     (setenv "GEM_HOME" gem-home)
     (mkdir-p gem-home)
-    (zero? (apply system* "gem" "install" (first-matching-file "\\.gem$")
-                  "--local" "--ignore-dependencies"
-                  ;; Executables should go into /bin, not /lib/ruby/gems.
-                  "--bindir" (string-append out "/bin")
-                  gem-flags))))
+    (and (apply system* "gem" "install" gem-name
+                "--local" "--ignore-dependencies"
+                ;; Executables should go into /bin, not /lib/ruby/gems.
+                "--bindir" (string-append out "/bin")
+                gem-flags)
+         ;; Remove the cached gem file as this is unnecessary and contains
+         ;; timestamped files rendering builds not reproducible.
+         (begin (delete-file (string-append gem-home "/cache/" gem-name))
+                #t))))
 
 (define %standard-phases
   (modify-phases gnu:%standard-phases