From 5f690393fdc6883c3a756fbceeeeb00e1dd2c0a1 Mon Sep 17 00:00:00 2001
From: Rutherther <rutherther@ditigal.xyz>
Date: Sat, 31 Jan 2026 13:57:44 +0100
Subject: [PATCH] feat: add system tests support

---
 etc/manifests/system-tests.scm | 61 ++++++++++++++++++++++++++++++++++
 modules/ruther.scm             |  3 ++
 modules/ruther/tests.scm       | 27 +++++++++++++++
 3 files changed, 91 insertions(+)
 create mode 100644 etc/manifests/system-tests.scm
 create mode 100644 modules/ruther.scm
 create mode 100644 modules/ruther/tests.scm

diff --git a/etc/manifests/system-tests.scm b/etc/manifests/system-tests.scm
new file mode 100644
index 0000000000000000000000000000000000000000..5be3a50f555804de473457612c1b857348f38f0a
--- /dev/null
+++ b/etc/manifests/system-tests.scm
@@ -0,0 +1,61 @@
+;;; This file has been taken from GNU Guix.
+;;; The original copyright header follows.
+
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2016, 2018-2020, 2022 Ludovic Courtès <ludo@gnu.org>
+;;;
+;;;
+;;; 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 (ruther tests)
+             (gnu tests)
+             (gnu packages package-management)
+             (guix monads)
+             (guix store)
+             ((guix git-download) #:select (git-predicate))
+             ((guix utils) #:select (current-source-directory))
+             (git)
+             (srfi srfi-1)
+             (ice-9 match))
+
+(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* (filter-tests
+          #:key
+          (tests (ruther-system-tests))
+          (filter-tests (getenv "TESTS")))
+  (match filter-tests
+    (#f
+     tests)
+    ((= string-tokenize (filter-tests ...))
+     (filter (lambda (test)
+               (member (system-test-name test) filter-tests))
+             tests))))
+
+(define (system-test-manifest)
+  "Return a manifest containing all the system tests, or all those selected by
+the 'TESTS' environment variable."
+  (let* ((tests (filter-tests)))
+    (format (current-error-port) "Selected ~a system tests...~%"
+            (length tests))
+
+    (manifest (map system-test->manifest-entry tests))))
+
+;; Return the manifest.
+(system-test-manifest)
diff --git a/modules/ruther.scm b/modules/ruther.scm
new file mode 100644
index 0000000000000000000000000000000000000000..bc3138fff1d01153a48be11fec2556ba63c1b213
--- /dev/null
+++ b/modules/ruther.scm
@@ -0,0 +1,3 @@
+(define-module (ruther))
+
+;; Dummy for now.
diff --git a/modules/ruther/tests.scm b/modules/ruther/tests.scm
new file mode 100644
index 0000000000000000000000000000000000000000..d50ec06391b3f2656f959970df4896da2cc7e700
--- /dev/null
+++ b/modules/ruther/tests.scm
@@ -0,0 +1,27 @@
+(define-module (ruther tests)
+  #:use-module (gnu tests)
+  #:use-module (guix discovery)
+  #:use-module (guix ui)
+  #:export (ruther-test-modules
+            fold-ruther-system-tests
+            ruther-system-tests))
+
+(define (ruther-test-modules)
+  "Return the list of modules that define system tests."
+  (scheme-modules (dirname (search-path %load-path "ruther.scm"))
+                  "ruther/tests"
+                  #:warn warn-about-load-error))
+
+(define (fold-ruther-system-tests proc seed)
+  "Invoke PROC on each system test, passing it the test and the previous
+result."
+  (fold-module-public-variables (lambda (obj result)
+                                  (if (system-test? obj)
+                                      (cons obj result)
+                                      result))
+                                '()
+                                (ruther-test-modules)))
+
+(define (ruther-system-tests)
+  "Return the list of system tests."
+  (reverse (fold-ruther-system-tests cons '())))