Add 'guix locate'.

* guix/scripts/locate.scm, tests/guix-locate.sh: New files.
* Makefile.am (MODULES): Add 'guix/scripts/locate.scm'.
(SH_TESTS): Add 'tests/guix-locate.sh'.
* po/guix/POTFILES.in: Add it.
* doc/guix.texi (Invoking guix locate): New node.

Co-authored-by: Antoine R. Dumont <antoine.romain.dumont@gmail.com>

tests/guix-locate.sh

@@ -0,0 +1,72 @@
+# GNU Guix --- Functional package management for GNU
+# Copyright © 2023 Antoine R. Dumont <antoine.romain.dumont@gmail.com>
+# Copyright © 2023 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/>.
+
+#
+# Test the 'guix locate' command-line utility.
+#
+
+set -x
+
+RUN_EXPENSIVE_TESTS="${RUN_EXPENSIVE_TESTS:-false}"
+
+tmpdir="guix-index-$$"
+# In the following tests, we use two different databases, one for each
+# indexation method.
+tmpdb_manifests="$tmpdir/manifests/db.sqlite"
+tmpdb_store="$tmpdir/store/db.sqlite"
+trap 'rm -rf "$tmpdir" "$tmpdb_store" "$tmpdb_manifests"' EXIT
+
+guix locate --version
+
+# Preparing db locations for both indexation methods.
+mkdir -p "$(dirname "$tmpdb_manifests")" "$(dirname "$tmpdb_store")"
+
+cmd_manifests="guix locate --database=$tmpdb_manifests --method=manifests"
+cmd_store="guix locate --database=$tmpdb_store --method=store"
+
+# Lookup without any db should fail.
+guix locate --database="$tmpdb_manifests" guile && false
+guix locate --database="$tmpdb_store" guile && false
+
+# Lookup without anything in db should yield no results because the indexer
+# didn't stumble upon any profile.
+test -z "$(guix locate --database="$tmpdb_manifests" guile)"
+
+# Install a package.
+guix package --bootstrap --install guile-bootstrap \
+     --profile="$tmpdir/profile"
+
+# Look for 'guile'.
+$cmd_manifests --update
+$cmd_manifests guile | grep "$(guix build guile-bootstrap)/bin/guile"
+$cmd_manifests boot-9.scm | grep ^guile-bootstrap
+
+# Using a glob pattern.
+$cmd_manifests -g '*.scm' | grep "^guile-bootstrap.*boot-9"
+
+# Statistics.
+$cmd_manifests --stats
+
+if $RUN_EXPENSIVE_TESTS
+then
+    $cmd_store --update
+    $cmd_store guile
+    $cmd_store guile | grep "$(guix build guile-bootstrap)/bin/guile"
+    $cmd_store boot-9.scm | grep ^guile-bootstrap
+fi