test: Modernize btrfs tests

Convert test-btrfs to use the test framework and
assertions, merge the physical offset test into it
and beef it up to include what TEST-83-BTRFS does and
finally get rid of TEST-83-BTRFS as it is unneeded now.

(cherry picked from commit 7cc5d161e6)
(cherry picked from commit 1a16a22bb7)

test/integration-tests/TEST-83-BTRFS/meson.build

@@ -1,8 +0,0 @@
-# SPDX-License-Identifier: LGPL-2.1-or-later
-
-integration_tests += [
-        integration_test_template + {
-                'name' : fs.name(meson.current_source_dir()),
-                'vm' : true,
-        },
-]

test/integration-tests/meson.build

@@ -96,7 +96,6 @@ foreach dirname : [
         'TEST-80-NOTIFYACCESS',
         'TEST-81-GENERATORS',
         'TEST-82-SOFTREBOOT',
-        'TEST-83-BTRFS',
         'TEST-84-STORAGETM',
         'TEST-85-NETWORK',
         'TEST-86-MULTI-PROFILE-UKI',

test/units/TEST-83-BTRFS.sh

@@ -1,32 +0,0 @@
-#!/usr/bin/env bash
-# SPDX-License-Identifier: LGPL-2.1-or-later
-set -eux
-set -o pipefail
-
-FSTYPE="$(stat --file-system --format "%T" /)"
-
-if [[ "$FSTYPE" != "btrfs" ]]; then
-    echo "Root filesystem is $FSTYPE instead of btrfs, skipping"
-    exit 77
-fi
-
-TEST_BTRFS_OFFSET=/usr/lib/systemd/tests/unit-tests/manual/test-btrfs-physical-offset
-
-SWAPFILE=/var/tmp/swapfile
-
-btrfs filesystem mkswapfile -s 10m "$SWAPFILE"
-sync -f "$SWAPFILE"
-
-offset_btrfs_progs="$(btrfs inspect-internal map-swapfile -r "$SWAPFILE")"
-echo "btrfs-progs: $offset_btrfs_progs"
-
-offset_btrfs_util="$("$TEST_BTRFS_OFFSET" "$SWAPFILE")"
-echo "btrfs-util: $offset_btrfs_util"
-
-(( offset_btrfs_progs == offset_btrfs_util ))
-
-rm -f "$SWAPFILE"
-
-/usr/lib/systemd/tests/unit-tests/manual/test-btrfs
-
-touch /testok