derivations: Move grafts to (guix grafts).

* guix/derivations.scm (<graft>, graft-derivation, %graft?)
(set-grafting): Move to...
* guix/grafts.scm: ... here.  New file.
* guix/gexp.scm, guix/packages.scm, tests/packages.scm,
guix/scripts/build.scm: Use it.
* Makefile.am (MODULES): Add it.
(SCM_TESTS): Add tests/grafts.scm.
* tests/derivations.scm ("graft-derivation"): Move to...
* tests/grafts.scm: ... here.  New file.

3 files changed, 83 insertions, 35 deletions

diff --git a/tests/derivations.scm b/tests/derivations.scm
index db96e26ab1..9b53019cc5 100644
--- a/tests/derivations.scm
+++ b/tests/derivations.scm
@@ -929,40 +929,6 @@
                                     ((p2 . _)
                                      (string<? p1 p2)))))))))))))
 
-
-(test-assert "graft-derivation"
-  (let* ((build `(begin
-                   (mkdir %output)
-                   (chdir %output)
-                   (symlink %output "self")
-                   (call-with-output-file "text"
-                     (lambda (output)
-                       (format output "foo/~a/bar" ,%mkdir)))
-                   (symlink ,%bash "sh")))
-         (orig  (build-expression->derivation %store "graft" build
-                                              #:inputs `(("a" ,%bash)
-                                                         ("b" ,%mkdir))))
-         (one   (add-text-to-store %store "bash" "fake bash"))
-         (two   (build-expression->derivation %store "mkdir"
-                                              '(call-with-output-file %output
-                                                 (lambda (port)
-                                                   (display "fake mkdir" port)))))
-         (graft (graft-derivation %store "graft" orig
-                                  (list (graft
-                                          (origin %bash)
-                                          (replacement one))
-                                        (graft
-                                          (origin %mkdir)
-                                          (replacement two))))))
-    (and (build-derivations %store (list graft))
-         (let ((two   (derivation->output-path two))
-               (graft (derivation->output-path graft)))
-           (and (string=? (format #f "foo/~a/bar" two)
-                          (call-with-input-file (string-append graft "/text")
-                            get-string-all))
-                (string=? (readlink (string-append graft "/sh")) one)
-                (string=? (readlink (string-append graft "/self")) graft))))))
-
 (test-equal "map-derivation"
   "hello"
   (let* ((joke (package-derivation %store guile-1.8))
diff --git a/tests/grafts.scm b/tests/grafts.scm
new file mode 100644
index 0000000000..c11403be19
--- /dev/null
+++ b/tests/grafts.scm
@@ -0,0 +1,81 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2014, 2015, 2016 Ludovic Courtès <ludo@gnu.org>
+;;;
+;;; 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 (test-grafts)
+  #:use-module (guix derivations)
+  #:use-module (guix store)
+  #:use-module (guix utils)
+  #:use-module (guix grafts)
+  #:use-module (guix tests)
+  #:use-module ((gnu packages) #:select (search-bootstrap-binary))
+  #:use-module (srfi srfi-64)
+  #:use-module (rnrs io ports))
+
+(define %store
+  (open-connection-for-tests))
+
+(define (bootstrap-binary name)
+  (let ((bin (search-bootstrap-binary name (%current-system))))
+    (and %store
+         (add-to-store %store name #t "sha256" bin))))
+
+(define %bash
+  (bootstrap-binary "bash"))
+(define %mkdir
+  (bootstrap-binary "mkdir"))
+
+
+(test-begin "grafts")
+
+(test-assert "graft-derivation"
+  (let* ((build `(begin
+                   (mkdir %output)
+                   (chdir %output)
+                   (symlink %output "self")
+                   (call-with-output-file "text"
+                     (lambda (output)
+                       (format output "foo/~a/bar" ,%mkdir)))
+                   (symlink ,%bash "sh")))
+         (orig  (build-expression->derivation %store "graft" build
+                                              #:inputs `(("a" ,%bash)
+                                                         ("b" ,%mkdir))))
+         (one   (add-text-to-store %store "bash" "fake bash"))
+         (two   (build-expression->derivation %store "mkdir"
+                                              '(call-with-output-file %output
+                                                 (lambda (port)
+                                                   (display "fake mkdir" port)))))
+         (graft (graft-derivation %store "graft" orig
+                                  (list (graft
+                                          (origin %bash)
+                                          (replacement one))
+                                        (graft
+                                          (origin %mkdir)
+                                          (replacement two))))))
+    (and (build-derivations %store (list graft))
+         (let ((two   (derivation->output-path two))
+               (graft (derivation->output-path graft)))
+           (and (string=? (format #f "foo/~a/bar" two)
+                          (call-with-input-file (string-append graft "/text")
+                            get-string-all))
+                (string=? (readlink (string-append graft "/sh")) one)
+                (string=? (readlink (string-append graft "/self")) graft))))))
+
+(test-end)
+
+
+(exit (= (test-runner-fail-count (test-runner-current)) 0))
diff --git a/tests/packages.scm b/tests/packages.scm
index 9d37fb68d6..68ab3f897b 100644
--- a/tests/packages.scm
+++ b/tests/packages.scm
@@ -1,5 +1,5 @@
 ;;; GNU Guix --- Functional package management for GNU
-;;; Copyright © 2012, 2013, 2014, 2015 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright © 2012, 2013, 2014, 2015, 2016 Ludovic Courtès <ludo@gnu.org>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -29,6 +29,7 @@
   #:use-module (guix hash)
   #:use-module (guix derivations)
   #:use-module (guix packages)
+  #:use-module (guix grafts)
   #:use-module (guix search-paths)
   #:use-module (guix build-system)
   #:use-module (guix build-system trivial)