Merge branch 'core-updates'

download: Remove a SourceForge mirror that never returns 404.

* guix/download.scm (%mirrors)[sourceforge]: Remove
nbtelecom.dl.sourceforge.net, which never returns 404 responses.  This causes
download failures due to hash mismatch, effectively preventing secondary
source URLs from being queried.

graft: Correctly replace references near the end of the scan buffer.

Fixes <http://bugs.gnu.org/28212>.
Reported by Leo Famulari <leo@famulari.name>.

* guix/build/graft.scm (replace-store-references): When I >= END, check
whether WRITTEN > END and call 'get-bytevector-n!' when it is.
* tests/grafts.scm (buffer-size): New variable.
("replace-store-references, <http://bugs.gnu.org/28212>"): New test.

Revert "graph: Provide access to the package record in the emit functions."

This reverts commit 5d7e8543659874682b618bba799ba7cd6ffce554, which
broke 'tests/graph.scm' and broke node types not related to <package>
objects, such as '%reference-node-type'.

packages: Use Guile 2.0 for grafting.

Works around <https://bugs.gnu.org/28211>.
Reported by Marius Bakke <mbakke@fastmail.com>.

* guix/packages.scm (guile-2.0): New procedure.
(package-derivation, package-cross-derivation): Use it when computing
the #:guile argument to 'graft-derivation'.

gnu: bootloader: Deprecate "device" field in favor of "target".

* gnu/bootloader.scm (<bootloader-configuration>): Deprecate "device" field in
favor of "target" field.  This is mostly a renaming but also a generalization
to support UEFI targets being paths to a mounted partition instead of a device
name.
* gnu/system/examples/bare-bones.tmpl:
* gnu/system/examples/desktop.tmpl:
* gnu/system/examples/lightweight-desktop.tmpl:
* gnu/system/examples/vm-image.tmpl:
* gnu/system/install.scm:
* gnu/tests.scm:
* gnu/tests/install.scm:
* gnu/tests/nfs.scm:
* tests/system.scm: Adapt all invocations of bootloader-configuration.
* guix/scripts/system.scm (perform-action): Rename device argument to
bootloader-target.
(process-action): Adapt caller.
* doc/guix.texi (Proceeding with the Installation):
* doc/guix.texi (Bootloader Configuration): Update documentation.

gnu: scripts: Cleanup regarding "gnu system" bootloader devices.

* guix/scripts/system.scm (install-bootloader, install): Remove unused
"device" argument.
(reinstall-bootloader, perform-action): Adapt callers.

Merge branch 'master' into core-updates

guix download: Support retrieving local file without the URI scheme.

* guix/scripts/download.scm (guix-download): Treat the URL argument as a local
file path when it fails on 'string->uri'.  Call 'fetch' with the processed
'uri' instead of the original URL argument.
* tests/guix-download.sh: Adjust accordingly.

pack: Add "none" compressor.

* guix/scripts/pack.scm (%compressors): Add compressor "none"; prepend
extension with ".".
(self-contained-tarball, docker-image): Assume compressor extensions start
with period.
* doc/guix.texi (Invoking guix pack): Document it.

Merge branch 'master' into core-updates

download: Add the canonical GnuPG download site.

* guix/download.scm (%mirrors)<gnupg>: Add https://gnupg.org.

profiles: Only check file contents if the file exists.

* guix/profiles.scm (fonts-dir-file): Check that files exist before using
"empty-file?".

Merge branch 'master' into core-updates

build: Add minify build system.

* guix/build-system/minify.scm: New file.
* guix/build/minify-build-system: New file.
* Makefile.am (MODULES): Add new files.
* doc/guix.texi (Build Systems): Document minify-build-system.

pull: Honor '--no-grafts'.

* guix/scripts/pull.scm (guix-pull): Parameterize %GRAFT? as a function
of OPTS.

pull: Use the commit ID as the version string.

* guix/scripts/pull.scm (build-from-source): Add #:commit parameter.
Pass it to BUILD.
(build-and-install): Add #:commit and pass it to 'build-from-source'.
(guix-pull): Pass #:commit to 'build-and-install'.

pull: Fetch source code from Git.

* guix/scripts/pull.scm (%snapshot-url, with-environment-variable)
(with-PATH): Remove.
(ensure-guile-git!): New procedure.
(%repository-url): New variable.
(%default-options): Add 'repository-url' and 'ref'.
(show-help, %options): Add '--commit' and '--url'.
(temporary-directory, first-directory, interned-then-deleted)
(unpack): Remove.
(build-from-source): Rename 'tarball' to 'source'.  Remove call to
'unpack'.
(build-and-install): Rename 'tarball' to 'source'.
(honor-lets-encrypt-certificates!, report-git-error): New procedures.
(with-git-error-handling): New macro.
(guix-pull)[fetch-tarball]: Remove.
Wrap body in 'with-git-error-handling'.  Rewrite to use
'latest-repository-commit'.
* build-aux/build-self.scm (build): Print an error message and exit when
GUILE-GIT is #f.
* doc/guix.texi (Invoking guix pull): Mention Git.  Document '--commit'
and '--branch'.

Merge branch 'master' into core-updates

graph: Provide access to the package record in the emit functions.

* guix/graph.scm (export-graph): Pass the node to the emit functions, instead
  of the node's label.