Merge branch 'master' into core-updates

scripts: Add 'build-package'.

* guix/scripts/system.scm (maybe-build): Move to ...
* guix/scripts.scm: ...here.
  (build-package): New procedure.

Co-authored-by: Ludovic Courtès <ludo@gnu.org>

Add (guix scripts).

* guix/ui.scm: Add missing copyright lines.
  (args-fold*, environment-build-options, %default-argument-handler,
  parse-command-line): Move to ...
* guix/scripts.scm: ...here.  New file.
* guix/scripts/archive.scm: Use it.
* guix/scripts/build.scm: Likewise.
* guix/scripts/download.scm: Likewise.
* guix/scripts/edit.scm: Likewise.
* guix/scripts/environment.scm: Likewise.
* guix/scripts/gc.scm: Likewise.
* guix/scripts/graph.scm: Likewise.
* guix/scripts/hash.scm: Likewise.
* guix/scripts/import/cpan.scm: Likewise.
* guix/scripts/import/cran.scm: Likewise.
* guix/scripts/import/elpa.scm: Likewise.
* guix/scripts/import/gem.scm: Likewise.
* guix/scripts/import/gnu.scm: Likewise.
* guix/scripts/import/hackage.scm: Likewise.
* guix/scripts/import/nix.scm: Likewise.
* guix/scripts/import/pypi.scm: Likewise.
* guix/scripts/lint.scm: Likewise.
* guix/scripts/package.scm: Likewise.
* guix/scripts/publish.scm: Likewise.
* guix/scripts/pull.scm: Likewise.
* guix/scripts/refresh.scm: Likewise.
* guix/scripts/size.scm: Likewise.
* guix/scripts/system.scm: Likewise.
* tests/ui.scm (with-environment-variable, "parse-command-line",
  "parse-command-line and --no options"): Move to ...
* tests/scripts.scm: ...here.  New file.
* Makefile.am (MODULES): Add guix/scripts.scm.
  (SCM_TESTS): Add tests/scripts.scm.
* po/guix/POTFILES.in: Add guix/scripts.scm.

guix system: Gracefully handle incomplete commands.

Fixes <http://bugs.gnu.org/21451>.
Reported by Steve Sprang <steve.sprang@gmail.com>.

* guix/scripts/system.scm (guix-system)[option-arguments]: Error out
  when ACTION is #f.

Merge branch 'master' into core-updates

system: Add 'kernel-arguments' field.

* gnu/system.scm (<operating-system>)[kernel-arguments]: New field.
  (operating-system-grub.cfg): Honor it.
  (operating-system-parameters-file): Add 'kernel-arguments' to the parameters
  file.
* guix/scripts/system.scm (previous-grub-entries)[system->grub-entry]: Read
  the 'kernel-arguments' field of the parameters file, when available.
* gnu/system/vm.scm (system-qemu-image/shared-store-script):
  Use (operating-system-kernel-arguments os) in '-append'.
* doc/guix.texi (operating-system Reference): Document it.

gnu: system: Move <file-system-mapping> into (gnu system file-systems).

* gnu/system/vm.scm (<file-system-mapping>, %store-mapping): Move from here...
* gnu/system/file-systems.scm: ...to here.
* guix/scripts/system.scm: Import (gnu system file-systems).

Merge branch 'master' into core-updates

guix system: init: Overwrite the items in the target store.

Fixes <http://bugs.gnu.org/20722>.
Reported by Eric Bavier <ericbavier@openmailbox.org>.

* guix/scripts/system.scm (copy-item): Check whether DEST exists and remove it
  if it does.

guix: Clean up --help messages.

* guix/scripts/import.scm (show-help): Add newline before a list of
  importers.
* guix/scripts/lint.scm (show-help): Split a long description line.
* guix/scripts/package.scm (show-help): Improve docstrings for --install
  and --remove options.
* guix/scripts/system.scm (show-help): Format actions the same way as
  guix commands and importers are formatted.

guix system: Add '--on-error'.

* guix/ui.scm (load*): Add #:on-error parameter.
  [tag, error-string]: New variables.
  Wrap 'load' call in 'call-with-prompt'.  Pass TAG to 'make-stack'.  Honor
  ON-ERROR after 'report-load-error' call.
  (report-load-error): Change to not exit on error.  Make private.
* guix/scripts/system.scm (show-help, %options): Add --on-error.
  (guix-system): Use 'load*' and pass it #:on-error.

guix system: init: Copy the closure of 'grub.cfg', not that of the system.

Fixes <http://bugs.gnu.org/20591>.
Reported by Daniel Pimentel <d4n1@openmailbox.org>.

* guix/scripts/system.scm (install): Copy the closure of GRUB.CFG rather than
  that of OS-DIR.

guix system: Always add zero previous entries in grub.cfg for 'init'.

* guix/scripts/system.scm (grub.cfg): Remove.
  (perform-action): Call 'operating-system-grub.cfg' with the empty list as
  the 2nd argument when ACTION is 'init.

Merge branch 'master' into gtk-rebuild

guix system: init: Make sure the target is root-owned.

Suggested by Mark H Weaver <mhw@netris.org>.

* guix/scripts/system.scm (install): Add 'chown' and 'chmod' calls for TARGET
  when running as root, and warn otherwise.

Merge branch 'master' into gtk-rebuild

Conflicts:
	gnu/packages/gtk.scm

ui: Deduplicate 'show-what-to-build*'.

* guix/ui.scm (show-what-to-build*): New procedure.
* guix/scripts/environment.scm (show-what-to-build*): Delete.
* guix/scripts/system.scm (show-what-to-build*): Likewise.
* build-aux/make-binary-tarball.scm (show-what-to-build*): Likewise.

ui: Factorize user-provided Scheme file loading.

* guix/ui.scm (make-user-module, load*): New procedures.
* guix/scripts/system.scm (%user-module): Define in terms of
  'make-user-module'.
  (read-operating-system): Define in terms of load*'.

Merge branch 'core-updates'

ui: Add 'report-load-error'.

* guix/scripts/system.scm (read-operating-system): Replace error
  handling code by a call to 'report-load-error'.
* guix/ui.scm (report-load-error): New procedure.