;;; GNU Guix --- Functional package management for GNU
;;; Copyright © 2019 Konrad Hinsen <konrad.hinsen@fastmail.net>
;;; Copyright © 2019, 2020, 2021, 2023 Ludovic Courtès <ludo@gnu.org>
;;; Copyright © 2021 Simon Tournier <zimon.toutoune@gmail.com>
;;; Copyright © 2023 Maxim Cournoyer <maxim.cournoyer@gmail.com>
;;;
;;; 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 scripts time-machine)
#:use-module (guix channels)
#:use-module (guix diagnostics)
#:use-module (guix ui)
#:use-module (guix scripts)
#:use-module (guix inferior)
#:use-module (guix store)
#:use-module (guix status)
#:use-module ((guix git)
#:select (update-cached-checkout with-git-error-handling))
#:use-module ((guix utils)
#:select (%current-system))
#:use-module ((guix scripts pull)
#:select (channel-list))
#:use-module ((guix scripts build)
#:select (%standard-build-options
show-build-options-help
set-build-options-from-command-line))
#:use-module (ice-9 match)
#:use-module (srfi srfi-1)
#:use-module (srfi srfi-11)
#:use-module (srfi srfi-26)
#:use-module (srfi srfi-34)
#:use-module (srfi srfi-37)
#:use-module (srfi srfi-71)
#:export (guix-time-machine))
;;;
;;; Command-line options.
;;;
(define (show-help)
(display (G_ "Usage: guix time-machine [OPTION] -- COMMAND ARGS...
Execute COMMAND ARGS... in an older version of Guix.\n"))
(display (G_ "
-C, --channels=FILE deploy the channels defined in FILE"))
(display (G_ "
-q, --no-channel-files
inhibit loading of user and system 'channels.scm'"))
(display (G_ "
--url=URL use the Git repository at URL"))
(display (G_ "
--commit=COMMIT use the specified COMMIT"))
(display (G_ "
--branch=BRANCH use the tip of the specified BRANCH"))
(display (G_ "
--disable-authentication
disable channel authentication"))
(newline)
(show-build-options-help)
(newline)
(display (G_ "
-h, --help display this help and exit"))
(display (G_ "
-V, --version display version information and exit"))
(newline)
(show-bug-report-information))
(define %options
;; Specifications of the command-line options.
(cons* (option '(#\C "channels") #t #f
(lambda (opt name arg result)
(alist-cons 'channel-file arg result)))
(option '(#\q "no-channel-files") #f #f
(lambda (opt name arg result)
(alist-cons 'ignore-channel-files? #t result)))
(option '("url") #t #f
(lambda (opt name arg result)
(alist-cons 'repository-url arg
(alist-delete 'repository-url result))))
(option '("commit") #t #f
(lambda (opt name arg result)
(alist-cons 'ref `(tag-or-commit . ,arg) result)))
(option '("branch") #t #f
(lambda (opt name arg result)
(alist-cons 'ref `(branch . ,arg) result)))
(option '("disable-authentication") #f #f
(lambda (opt name arg result)
(alist-cons 'authenticate-channels? #f result)))
(option '(#\h "help") #f #f
(lambda args
(leave-on-EPIPE (show-help))
(exit 0)))
(option '(#\V "version") #f #f
(lambda args
(show-version-and-exit "guix time-machine")))
%standard-build-options))
(define %default-options
;; Alist of default option values.
`((system . ,(%current-system))
(substitutes? . #t)
(offload? . #t)
(print-build-trace? . #t)
(print-extended-build-trace? . #t)
(multiplexed-build-output? . #t)
(authenticate-channels? . #t)
(graft? . #t)
(debug . 0)
(verbosity . 1)))
(define (parse-args args)
"Parse the list of command line arguments ARGS."
;; The '--' token is used to separate the command to run from the rest of
;; the operands.
(let-values (((args command) (break (cut string=? "--" <>) args)))
(let ((opts (parse-command-line args %options
(list %default-options))))
(when (assoc-ref opts 'argument)
(leave (G_ "~A: extraneous argument~%")
(assoc-ref opts 'argument)))
(match command
(() opts)
(("--") opts)
(("--" command ...) (alist-cons 'exec command opts))))))
;;;
;;; Avoiding traveling too far back.
;;;
;;; The required inferiors mechanism relied on by 'guix time-machine' was
;;; firmed up in v1.0.0; it is the oldest, safest commit that can be travelled
;;; to.
(define %oldest-possible-commit
"6298c3ffd9654d3231a6f25390b056483e8f407c") ;v1.0.0
(define %reference-channels
(list (channel (inherit %default-guix-channel)
(commit %oldest-possible-commit))))
(define (validate-guix-channel channel start commit relation)
"Raise an error if CHANNEL is the 'guix' channel and the RELATION of COMMIT
to %OLDEST-POSSIBLE-COMMIT is not that of an ancestor."
(unless (or (not (guix-channel? channel))
(memq relation '(ancestor self)))
(raise (formatted-message
(G_ "cannot travel past commit `~a' from May 1st, 2019")
(string-take %oldest-possible-commit 12)))))
;;;
;;; Entry point.
;;;
(define-command (guix-time-machine . args)
(synopsis "run commands from a different revision")
(with-error-handling
(with-git-error-handling
(let* ((opts (parse-args args))
(channels (channel-list opts))
(command-line (assoc-ref opts 'exec))
(ref (assoc-ref opts 'ref))
(substitutes? (assoc-ref opts 'substitutes?))
(authenticate? (assoc-ref opts 'authenticate-channels?)))
(if command-line
(let* ((directory
(with-store store
(with-status-verbosity (assoc-ref opts 'verbosity)
(with-build-handler (build-notifier #:use-substitutes?
substitutes?
#:verbosity
(assoc-ref opts 'verbosity)
#:dry-run? #f)
(set-build-options-from-command-line store opts)
(cached-channel-instance store channels
#:authenticate? authenticate?
#:reference-channels
%reference-channels
#:validate-channels
validate-guix-channel)))))
(executable (string-append directory "/bin/guix")))
(apply execl (cons* executable executable command-line)))
(warning (G_ "no command specified; nothing to do~%")))))))