tests: Add a manifest for system tests.

The manifest can be passed to 'guix build -m', 'guix weather -m', and so
on.  It can also be passed to an installed 'guix' (without
./pre-inst-env), with the exception so far of installation tests.

* build-aux/run-system-tests.scm: Remove.  Move interesting bits move
to...
* etc/system-tests.scm: ... here.  New file.
* Makefile.am (EXTRA_DIST): Remove 'build-aux/run-system-tests.scm' and
add 'etc/system-tests.scm'.
(check-system): Rewrite to run 'guix build -m etc/system-tests.scm'.

1 files changed, 94 insertions, 0 deletions

diff --git a/etc/system-tests.scm b/etc/system-tests.scm
new file mode 100644
index 0000000000..ab2827e70a
--- /dev/null
+++ b/etc/system-tests.scm
@@ -0,0 +1,94 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2016, 2018, 2019, 2020 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/>.
+
+(use-modules (gnu tests)
+             (gnu packages package-management)
+             ((gnu ci) #:select (channel-source->package))
+             ((guix git-download) #:select (git-predicate))
+             ((guix utils) #:select (current-source-directory))
+             (git)
+             (ice-9 match))
+
+(define (source-commit directory)
+  "Return the commit of the head of DIRECTORY or #f if it could not be
+determined."
+  (let ((repository #f))
+    (catch 'git-error
+      (lambda ()
+        (set! repository (repository-open directory))
+        (let* ((head   (repository-head repository))
+               (target (reference-target head))
+               (commit (oid->string target)))
+          (repository-close! repository)
+          commit))
+      (lambda _
+        (when repository
+          (repository-close! repository))
+        #f))))
+
+(define (tests-for-current-guix source commit)
+  "Return a list of tests for perform, using Guix built from SOURCE, a channel
+instance."
+  ;; Honor the 'TESTS' environment variable so that one can select a subset
+  ;; of tests to run in the usual way:
+  ;;
+  ;;   make check-system TESTS=installed-os
+  (parameterize ((current-guix-package
+                  (channel-source->package source #:commit commit)))
+    (match (getenv "TESTS")
+      (#f
+       (all-system-tests))
+      ((= string-tokenize (tests ...))
+       (filter (lambda (test)
+                 (member (system-test-name test) tests))
+               (all-system-tests))))))
+
+(define (system-test->manifest-entry test)
+  "Return a manifest entry for TEST, a system test."
+  (manifest-entry
+    (name (string-append "test." (system-test-name test)))
+    (version "0")
+    (item test)))
+
+(define (system-test-manifest)
+  "Return a manifest containing all the system tests, or all those selected by
+the 'TESTS' environment variable."
+  (define source
+    (string-append (current-source-directory) "/.."))
+
+  (define commit
+    ;; Fetch the current commit ID so we can potentially build the same
+    ;; derivation as ci.guix.gnu.org.
+    (source-commit source))
+
+  ;; Intern SOURCE so that 'build-from-source' in (guix channels) sees
+  ;; "fresh" file names and thus doesn't find itself loading .go files
+  ;; from ~/.cache/guile when it loads 'build-aux/build-self.scm'.
+  (let* ((source (local-file source "guix-source"
+                             #:recursive? #t
+                             #:select?
+                             (or (git-predicate source)
+                                 (const #t))))
+         (tests  (tests-for-current-guix source commit)))
+    (format (current-error-port) "Selected ~a system tests...~%"
+            (length tests))
+
+    (manifest (map system-test->manifest-entry tests))))
+
+;; Return the manifest.
+(system-test-manifest)