build: Add R build system.

* guix/build-system/r.scm: New file.
* guix/build/r-build-system: New file.
* Makefile.am (MODULES): Add new files.
* doc/guix.texi (Build Systems): Document r-build-system.

1 files changed, 112 insertions, 0 deletions

diff --git a/guix/build/r-build-system.scm b/guix/build/r-build-system.scm
new file mode 100644
index 0000000000..3fc13eb835
--- /dev/null
+++ b/guix/build/r-build-system.scm
@@ -0,0 +1,112 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2015 Ricardo Wurmus <rekado@elephly.net>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix is free software; you can redistribute it and/or modify it
+;;; under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 3 of the License, or (at
+;;; your option) any later version.
+;;;
+;;; GNU Guix is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;;; GNU General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (guix build r-build-system)
+  #:use-module ((guix build gnu-build-system) #:prefix gnu:)
+  #:use-module (guix build utils)
+  #:use-module (ice-9 match)
+  #:use-module (ice-9 ftw)
+  #:use-module (ice-9 popen)
+  #:use-module (srfi srfi-1)
+  #:use-module (srfi srfi-26)
+  #:export (%standard-phases
+            r-build))
+
+;; Commentary:
+;;
+;; Builder-side code of the standard build procedure for R packages.
+;;
+;; Code:
+
+(define (invoke-r command params)
+  (zero? (apply system* "R" "CMD" command params)))
+
+(define (pipe-to-r command params)
+  (let ((port (apply open-pipe* OPEN_WRITE "R" params)))
+    (display command port)
+    (zero? (status:exit-val (close-pipe port)))))
+
+(define (generate-site-path inputs)
+  (string-join (map (match-lambda
+                      ((_ . path)
+                       (string-append path "/site-library")))
+                    ;; Restrict to inputs beginning with "r-".
+                    (filter (match-lambda
+                              ((name . _)
+                               (string-prefix? "r-" name)))
+                            inputs))
+               ":"))
+
+(define* (check #:key test-target inputs outputs tests? #:allow-other-keys)
+  "Run the test suite of a given R package."
+  (let* ((libdir    (string-append (assoc-ref outputs "out") "/site-library/"))
+
+         ;; R package names are case-sensitive and cannot be derived from the
+         ;; Guix package name.  The exact package name is required as an
+         ;; argument to ‘tools::testInstalledPackage’, which runs the tests
+         ;; for a package given its name and the path to the “library” (a
+         ;; location for a collection of R packages) containing it.
+
+         ;; Since there can only be one R package in any collection (=
+         ;; “library”), the name of the only directory in the collection path
+         ;; is the original name of the R package.
+         (pkg-name  (car (scandir libdir (negate (cut member <> '("." ".."))))))
+         (testdir   (string-append libdir pkg-name "/" test-target))
+         (site-path (string-append libdir ":" (generate-site-path inputs))))
+    (if (and tests? (file-exists? testdir))
+        (begin
+          (setenv "R_LIBS_SITE" site-path)
+          (pipe-to-r (string-append "tools::testInstalledPackage(\"" pkg-name "\", "
+                                    "lib.loc = \"" libdir "\")")
+                     '("--no-save" "--slave")))
+        #t)))
+
+(define* (install #:key outputs inputs (configure-flags '())
+                  #:allow-other-keys)
+  "Install a given R package."
+  (let* ((out          (assoc-ref outputs "out"))
+         (site-library (string-append out "/site-library/"))
+         (params       (append configure-flags
+                               (list "--install-tests"
+                                     (string-append "--library=" site-library)
+                                     ".")))
+         (site-path    (string-append site-library ":"
+                                      (generate-site-path inputs))))
+    ;; If dependencies cannot be found at install time, R will refuse to
+    ;; install the package.
+    (setenv "R_LIBS_SITE" site-path)
+    ;; Some R packages contain a configure script for which the CONFIG_SHELL
+    ;; variable should be set.
+    (setenv "CONFIG_SHELL" (which "bash"))
+    (mkdir-p site-library)
+    (invoke-r "INSTALL" params)))
+
+(define %standard-phases
+  (modify-phases gnu:%standard-phases
+    (delete 'configure)
+    (delete 'build)
+    (delete 'check) ; tests must be run after installation
+    (replace 'install install)
+    (add-after 'install 'check check)))
+
+(define* (r-build #:key inputs (phases %standard-phases)
+                       #:allow-other-keys #:rest args)
+  "Build the given R package, applying all of PHASES in order."
+  (apply gnu:gnu-build #:inputs inputs #:phases phases args))
+
+;;; r-build-system.scm ends here