From a2d557374950d77cfda22eaf7aff04de720f148f Mon Sep 17 00:00:00 2001
From: Johannes Schauer Marin Rodrigues <josch@mister-muffin.de>
Date: Thu, 2 Feb 2023 07:57:58 +0100
Subject: [PATCH] tests: drop qemu requirements for tests that only use it to
 create a user by defaulting to SUDO_USER

---
 coverage.py                                   |  4 +-
 coverage.txt                                  | 30 +++++++------
 tests/as-debootstrap-unshare-wrapper          | 18 +++++---
 ...eck-for-bit-by-bit-identical-format-output | 37 +++++++--------
 tests/chrootless-fakeroot                     | 24 ++++++----
 tests/create-arm64-tarball                    | 20 +++++----
 tests/create-gzip-compressed-tarball          | 18 +++++---
 tests/create-tarball-dry-run                  |  7 ++-
 tests/custom-tmpdir                           | 24 ++++++----
 ...-directory-not-accessible-by-unshared-user | 27 +++++++----
 tests/dev-ptmx                                | 18 ++++----
 tests/install-doc-debian                      | 25 +++++++----
 tests/install-doc-debian-and-output-tarball   | 25 +++++++----
 tests/install-doc-debian-and-test-hooks       | 25 +++++++----
 tests/install-libmagic-mgc-on-arm64           | 25 +++++++----
 tests/jessie-or-older                         | 45 ++++++++++---------
 tests/missing-dev-sys-proc-inside-the-chroot  | 21 ++++++---
 tests/no-sbin-in-path                         | 26 ++++++-----
 tests/pivot_root                              | 20 ++++-----
 tests/root-mode-inside-unshare-chroot         | 29 +++++++-----
 tests/special-hooks-with-mode-mode            | 20 +++++----
 tests/unpack-doc-debian                       | 24 ++++++----
 tests/unshare-include-deb                     | 15 ++++---
 23 files changed, 322 insertions(+), 205 deletions(-)

diff --git a/coverage.py b/coverage.py
index cf6f30f..0ea034f 100755
--- a/coverage.py
+++ b/coverage.py
@@ -271,14 +271,14 @@ def main():
                 tt = "qemu"
             elif test.get("Needs-QEMU", "false") == "true":
                 tt = ("skip", "test needs QEMU")
+            elif mode == "unshare" and not have_unshare:
+                tt = ("skip", "test needs unshare")
             elif test.get("Needs-Root", "false") == "true":
                 tt = "sudo"
             elif mode == "auto" and not have_unshare:
                 tt = "sudo"
             elif mode == "root":
                 tt = "sudo"
-            elif mode == "unshare" and not have_unshare:
-                tt = ("skip", "test needs unshare")
             else:
                 tt = "null"
             tests.append((tt, name, dist, mode, variant, fmt))
diff --git a/coverage.txt b/coverage.txt
index ff18622..cc7c2ab 100644
--- a/coverage.txt
+++ b/coverage.txt
@@ -4,7 +4,7 @@ Variants: minbase buildd -
 Needs-Root: true
 
 Test: as-debootstrap-unshare-wrapper
-Needs-QEMU: true
+Modes: unshare
 
 Test: help
 
@@ -34,7 +34,7 @@ Test: root-mode-inside-chroot
 Needs-Root: true
 
 Test: root-mode-inside-unshare-chroot
-Needs-QEMU: true
+Modes: unshare
 
 Test: root-without-cap-sys-admin
 Needs-Root: true
@@ -43,7 +43,8 @@ Test: mount-is-missing
 Needs-QEMU: true
 
 Test: check-for-bit-by-bit-identical-format-output
-Needs-QEMU: true
+Needs-Root: true
+Modes: unshare fakechroot
 Formats: tar squashfs ext2
 Variants: essential apt minbase buildd - standard
 Skip-If:
@@ -51,6 +52,7 @@ Skip-If:
  variant == "important" and dist == "oldstable" # /var/lib/systemd/catalog/database differs
  fmt == "squashfs" and dist == "oldstable" # squashfs-tools-ng is not available
  fmt == "ext2" and dist == "oldstable" # genext2fs does not support SOURCE_DATE_EPOCH
+ mode == "fakechroot" and variant in ["-", "standard"] # no extended attributes
 
 Test: tarfilter-idshift
 Needs-QEMU: true
@@ -74,19 +76,21 @@ Test: missing-device-nodes-outside-the-chroot
 Needs-QEMU: true
 
 Test: missing-dev-sys-proc-inside-the-chroot
-Needs-QEMU: true
+Modes: unshare
+Variants: custom
 
 Test: chroot-directory-not-accessible-by-apt-user
 Needs-Root: true
 
 Test: cwd-directory-not-accessible-by-unshared-user
-Needs-QEMU: true
+Needs-Root: true
+Modes: unshare
 
 Test: create-gzip-compressed-tarball
-Needs-QEMU: true
 
 Test: custom-tmpdir
-Needs-QEMU: true
+Needs-Root: true
+Modes: unshare
 
 Test: xz-compressed-tarball
 
@@ -233,7 +237,6 @@ Needs-Root: true
 
 Test: special-hooks-with-mode-mode
 Modes: root unshare fakechroot
-Needs-QEMU: true
 
 Test: debootstrap-no-op-options
 Needs-Root: true
@@ -280,7 +283,6 @@ Variants: any
 Modes: any
 
 Test: unpack-doc-debian
-Needs-QEMU: true
 Modes: any
 Variants: extract
 
@@ -298,7 +300,6 @@ Skip-If:
 Test: chrootless-fakeroot
 Variants: essential
 Modes: chrootless
-Needs-QEMU: true
 Skip-If:
  dist in ["oldstable", "stable"]
 
@@ -320,6 +321,8 @@ Variants: custom
 Modes: chrootless
 
 Test: install-libmagic-mgc-on-arm64
+Variants: custom
+Modes: chrootless
 Skip-If:
  hostarch != "amd64"
  not have_binfmt
@@ -339,7 +342,6 @@ Modes: fakechroot
 
 Test: dev-ptmx
 Modes: root unshare
-Needs-QEMU: true
 
 Test: error-if-stdout-is-tty
 
@@ -349,14 +351,14 @@ Test: include-deb-file
 
 Test: unshare-include-deb
 Modes: unshare
-Needs-QEMU: true
 
 Test: pivot_root
 Modes: root unshare
-Needs-QEMU: true
+Skip-If: not have_unshare
 
 Test: jessie-or-older
-Needs-QEMU: true
+Needs-Root: true
+Modes: root unshare fakechroot
 Variants: essential apt minbase
 
 Test: apt-patterns
diff --git a/tests/as-debootstrap-unshare-wrapper b/tests/as-debootstrap-unshare-wrapper
index 75295b8..e928f33 100644
--- a/tests/as-debootstrap-unshare-wrapper
+++ b/tests/as-debootstrap-unshare-wrapper
@@ -2,12 +2,20 @@
 set -eu
 export LC_ALL=C.UTF-8
 export SOURCE_DATE_EPOCH={{ SOURCE_DATE_EPOCH }}
-if [ ! -e /mmdebstrap-testenv ]; then
-	echo "this test modifies the system and should only be run inside a container" >&2
-	exit 1
+
+prefix=
+if [ "$(id -u)" -eq 0 ] && [ "{{ MODE }}" != "root" ] && [ "{{ MODE }}" != "auto" ]; then
+	if ! id "${SUDO_USER:-user}" 2>/dev/null; then
+		if [ ! -e /mmdebstrap-testenv ]; then
+			echo "this test modifies the system and should only be run inside a container" >&2
+			exit 1
+		fi
+		useradd --home-dir "/home/${SUDO_USER:-user}" --create-home "${SUDO_USER:-user}"
+	fi
+	prefix="runuser -u ${SUDO_USER:-user} --"
 fi
-useradd --home-dir /home/user --create-home user
-runuser -u user -- {{ CMD }} --variant=custom --mode=unshare --setup-hook='env container=lxc debootstrap unstable "$1" {{ MIRROR }}' - /tmp/debian-mm.tar {{ MIRROR }}
+
+$prefix {{ CMD }} --variant=custom --mode={{ MODE }} --setup-hook='env container=lxc debootstrap unstable "$1" {{ MIRROR }}' - /tmp/debian-mm.tar {{ MIRROR }}
 
 mkdir /tmp/debian-mm
 tar --xattrs --xattrs-include='*' -C /tmp/debian-mm -xf /tmp/debian-mm.tar
diff --git a/tests/check-for-bit-by-bit-identical-format-output b/tests/check-for-bit-by-bit-identical-format-output
index 76b448e..39641c4 100644
--- a/tests/check-for-bit-by-bit-identical-format-output
+++ b/tests/check-for-bit-by-bit-identical-format-output
@@ -1,12 +1,21 @@
 #!/bin/sh
 set -eu
 export LC_ALL=C.UTF-8
-if [ ! -e /mmdebstrap-testenv ]; then
-	echo "this test modifies the system and should only be run inside a container" >&2
-	exit 1
-fi
-useradd --home-dir /home/user --create-home user
 export SOURCE_DATE_EPOCH={{ SOURCE_DATE_EPOCH }}
+
+trap "rm -f /tmp/debian-chroot-{{ MODE }}.{{ FORMAT }} /tmp/debian-chroot-root.{{ FORMAT }}" EXIT INT TERM
+
+[ "$(id -u)" -eq 0 ]
+
+if ! id "${SUDO_USER:-user}" 2>/dev/null; then
+	if [ ! -e /mmdebstrap-testenv ]; then
+		echo "this test modifies the system and should only be run inside a container" >&2
+		exit 1
+	fi
+	useradd --home-dir "/home/${SUDO_USER:-user}" --create-home "${SUDO_USER:-user}"
+fi
+prefix="runuser -u ${SUDO_USER:-user} --"
+
 {{ CMD }} --mode=root --variant={{ VARIANT }} {{ DIST }} /tmp/debian-chroot-root.{{ FORMAT }} {{ MIRROR }}
 if [ "{{ FORMAT }}" = tar ]; then
 	printf 'ustar ' | cmp --bytes=6 --ignore-initial=257:0 /tmp/debian-chroot-root.tar -
@@ -18,19 +27,11 @@ else
 	echo "unknown format: {{ FORMAT }}" >&2
 	exit 1
 fi
-runuser -u user -- {{ CMD }} --mode=unshare --variant={{ VARIANT }} {{ DIST }} /tmp/debian-chroot-unshare.{{ FORMAT }} {{ MIRROR }}
-cmp /tmp/debian-chroot-root.{{ FORMAT }} /tmp/debian-chroot-unshare.{{ FORMAT }}
-rm /tmp/debian-chroot-unshare.{{ FORMAT }}
-case {{ VARIANT }} in essential|apt|minbase|buildd)
-	# variants important and standard differ because permissions drwxr-sr-x
-	# and extended attributes of ./var/log/journal/ cannot be preserved
-	# in fakechroot mode
-	runuser -u user -- {{ CMD }} --mode=fakechroot --variant={{ VARIANT }} {{ DIST }} /tmp/debian-chroot-fakechroot.{{ FORMAT }} {{ MIRROR }}
-	cmp /tmp/debian-chroot-root.{{ FORMAT }} /tmp/debian-chroot-fakechroot.{{ FORMAT }}
-	rm /tmp/debian-chroot-fakechroot.{{ FORMAT }}
-	;;
-esac
+
+$prefix {{ CMD }} --mode={{ MODE }} --variant={{ VARIANT }} {{ DIST }} /tmp/debian-chroot-{{ MODE }}.{{ FORMAT }} {{ MIRROR }}
+cmp /tmp/debian-chroot-root.{{ FORMAT }} /tmp/debian-chroot-{{ MODE }}.{{ FORMAT }} \
+	|| diffoscope /tmp/debian-chroot-root.{{ FORMAT }} /tmp/debian-chroot-{{ MODE }}.{{ FORMAT }}
+
 # we cannot test chrootless mode here, because mmdebstrap relies on the
 # usrmerge package to set up merged-/usr and that doesn't work in chrootless
 # mode
-rm /tmp/debian-chroot-root.{{ FORMAT }}
diff --git a/tests/chrootless-fakeroot b/tests/chrootless-fakeroot
index 67c1e20..aa799dd 100644
--- a/tests/chrootless-fakeroot
+++ b/tests/chrootless-fakeroot
@@ -3,15 +3,21 @@ set -eu
 export LC_ALL=C.UTF-8
 export SOURCE_DATE_EPOCH={{ SOURCE_DATE_EPOCH }}
 trap "rm -f /tmp/chrootless.tar /tmp/root.tar" EXIT INT TERM
-if [ "$(id -u)" -eq 0 ] && ! id -u user > /dev/null 2>&1; then
-	if [ ! -e /mmdebstrap-testenv ]; then
-		echo "this test modifies the system and should only be run inside a container" >&2
-		exit 1
-	fi
-	useradd --home-dir /home/user --create-home user
-fi
+
+[ {{ MODE }} = chrootless ]
+
 prefix=
-[ "$(id -u)" -eq 0 ] && prefix="runuser -u user --"
+if [ "$(id -u)" -eq 0 ] && [ "{{ MODE }}" != "root" ] && [ "{{ MODE }}" != "auto" ]; then
+	if ! id "${SUDO_USER:-user}" 2>/dev/null; then
+		if [ ! -e /mmdebstrap-testenv ]; then
+			echo "this test modifies the system and should only be run inside a container" >&2
+			exit 1
+		fi
+		useradd --home-dir "/home/${SUDO_USER:-user}" --create-home "${SUDO_USER:-user}"
+	fi
+	prefix="runuser -u ${SUDO_USER:-user} --"
+fi
+
 # we need --hook-dir=./hooks/merged-usr because usrmerge does not understand
 # DPKG_ROOT
 # permissions drwxr-sr-x and extended attributes of ./var/log/journal/ cannot
@@ -21,7 +27,7 @@ for INCLUDE in '' 'apt' 'apt,build-essential' 'systemd-sysv'; do
 		--customize-hook='if [ -d "$1"/var/log/journal ]; then rmdir "$1"/var/log/journal; mkdir --mode=2755 "$1"/var/log/journal; chroot "$1" chown root:systemd-journal /var/log/journal; fi' \
 		${INCLUDE:+--include="$INCLUDE"} \
 		{{ DIST }} /tmp/root.tar {{ MIRROR }}
-	$prefix fakeroot {{ CMD }} --mode=chrootless --variant={{ VARIANT }} --hook-dir=./hooks/merged-usr \
+	$prefix fakeroot {{ CMD }} --mode={{ MODE }} --variant={{ VARIANT }} --hook-dir=./hooks/merged-usr \
 		${INCLUDE:+--include="$INCLUDE"} \
 		{{ DIST }} /tmp/chrootless.tar {{ MIRROR }}
 	cmp /tmp/root.tar /tmp/chrootless.tar
diff --git a/tests/create-arm64-tarball b/tests/create-arm64-tarball
index 5dfe679..db7f54b 100644
--- a/tests/create-arm64-tarball
+++ b/tests/create-arm64-tarball
@@ -1,15 +1,19 @@
 #!/bin/sh
 set -eu
 export LC_ALL=C.UTF-8
-if [ "$(id -u)" -eq 0 ] && ! id -u user > /dev/null 2>&1; then
-	if [ ! -e /mmdebstrap-testenv ]; then
-		echo "this test modifies the system and should only be run inside a container" >&2
-		exit 1
-	fi
-	useradd --home-dir /home/user --create-home user
-fi
+
 prefix=
-[ "$(id -u)" -eq 0 ] && [ "{{ MODE }}" != "root" ] && prefix="runuser -u user --"
+if [ "$(id -u)" -eq 0 ] && [ "{{ MODE }}" != "root" ] && [ "{{ MODE }}" != "auto" ]; then
+	if ! id "${SUDO_USER:-user}" 2>/dev/null; then
+		if [ ! -e /mmdebstrap-testenv ]; then
+			echo "this test modifies the system and should only be run inside a container" >&2
+			exit 1
+		fi
+		useradd --home-dir "/home/${SUDO_USER:-user}" --create-home "${SUDO_USER:-user}"
+	fi
+	prefix="runuser -u ${SUDO_USER:-user} --"
+fi
+
 [ "{{ MODE }}" = "fakechroot" ] && prefix="$prefix fakechroot fakeroot"
 $prefix {{ CMD }} --mode={{ MODE }} --variant=apt --architectures=arm64 {{ DIST }} /tmp/debian-chroot.tar {{ MIRROR }}
 # we ignore differences between architectures by ignoring some files
diff --git a/tests/create-gzip-compressed-tarball b/tests/create-gzip-compressed-tarball
index dc7deed..cbf772c 100644
--- a/tests/create-gzip-compressed-tarball
+++ b/tests/create-gzip-compressed-tarball
@@ -1,12 +1,20 @@
 #!/bin/sh
 set -eu
 export LC_ALL=C.UTF-8
-if [ ! -e /mmdebstrap-testenv ]; then
-	echo "this test modifies the system and should only be run inside a container" >&2
-	exit 1
+
+prefix=
+if [ "$(id -u)" -eq 0 ] && [ "{{ MODE }}" != "root" ] && [ "{{ MODE }}" != "auto" ]; then
+	if ! id "${SUDO_USER:-user}" 2>/dev/null; then
+		if [ ! -e /mmdebstrap-testenv ]; then
+			echo "this test modifies the system and should only be run inside a container" >&2
+			exit 1
+		fi
+		useradd --home-dir "/home/${SUDO_USER:-user}" --create-home "${SUDO_USER:-user}"
+	fi
+	prefix="runuser -u ${SUDO_USER:-user} --"
 fi
-useradd --home-dir /home/user --create-home user
-runuser -u user -- {{ CMD }} --mode=unshare --variant=apt {{ DIST }} /tmp/debian-chroot.tar.gz {{ MIRROR }}
+
+$prefix {{ CMD }} --mode={{ MODE }} --variant=apt {{ DIST }} /tmp/debian-chroot.tar.gz {{ MIRROR }}
 printf '\037\213\010' | cmp --bytes=3 /tmp/debian-chroot.tar.gz -
 tar -tf /tmp/debian-chroot.tar.gz | sort | diff -u tar1.txt -
 rm /tmp/debian-chroot.tar.gz
diff --git a/tests/create-tarball-dry-run b/tests/create-tarball-dry-run
index 997e827..91bee4a 100644
--- a/tests/create-tarball-dry-run
+++ b/tests/create-tarball-dry-run
@@ -8,15 +8,14 @@ export LC_ALL=C.UTF-8
 prefix=
 include=,
 if [ "$(id -u)" -eq 0 ] && [ "{{ MODE }}" != root ] && [ "{{ MODE }}" != auto ]; then
-	# this must be qemu
-	if ! id -u user >/dev/null 2>&1; then
+	if ! id "${SUDO_USER:-user}" 2>/dev/null; then
 		if [ ! -e /mmdebstrap-testenv ]; then
 			echo "this test modifies the system and should only be run inside a container" >&2
 			exit 1
 		fi
-		useradd --home-dir /home/user --create-home user
+		useradd --home-dir "/home/${SUDO_USER:-user}" --create-home "${SUDO_USER:-user}"
 	fi
-	prefix="runuser -u user --"
+	prefix="runuser -u ${SUDO_USER:-user} --"
 	if [ "{{ VARIANT }}" = extract ] || [ "{{ VARIANT }}" = custom ]; then
 		include="$(tr '\n' ',' < pkglist.txt)"
 	fi
diff --git a/tests/custom-tmpdir b/tests/custom-tmpdir
index 3d3ac4d..628cb37 100644
--- a/tests/custom-tmpdir
+++ b/tests/custom-tmpdir
@@ -1,25 +1,33 @@
 #!/bin/sh
 set -eu
 export LC_ALL=C.UTF-8
-if [ ! -e /mmdebstrap-testenv ]; then
-	echo "this test modifies the system and should only be run inside a container" >&2
-	exit 1
+
+[ "$(id -u)" -eq 0 ]
+[ {{ MODE }} = "unshare" ]
+
+if ! id "${SUDO_USER:-user}" 2>/dev/null; then
+	if [ ! -e /mmdebstrap-testenv ]; then
+		echo "this test modifies the system and should only be run inside a container" >&2
+		exit 1
+	fi
+	useradd --home-dir "/home/${SUDO_USER:-user}" --create-home "${SUDO_USER:-user}"
 fi
+prefix="runuser -u ${SUDO_USER:-user} --"
+
 # https://www.etalabs.net/sh_tricks.html
 quote () { printf %s\\n "$1" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/'/" ; }
-useradd --home-dir /home/user --create-home user
-homedir=$(runuser -u user -- sh -c 'cd && pwd')
+homedir=$($prefix sh -c 'cd && pwd')
 # apt:test/integration/test-apt-key
 TMPDIR_ADD="This is fü\$\$ing cràzy, \$(apt -v)\$!"
-runuser -u user -- mkdir "$homedir/$TMPDIR_ADD"
+$prefix mkdir "$homedir/$TMPDIR_ADD"
 # make sure the unshared user can traverse into the TMPDIR
 chmod 711 "$homedir"
 # set permissions and sticky bit like the real /tmp
 chmod 1777 "$homedir/$TMPDIR_ADD"
-runuser -u user -- env TMPDIR="$homedir/$TMPDIR_ADD" {{ CMD }} --mode=unshare --variant=apt \
+$prefix env TMPDIR="$homedir/$TMPDIR_ADD" {{ CMD }} --mode={{ MODE }} --variant=apt \
 	--setup-hook='case "$1" in '"$(quote "$homedir/$TMPDIR_ADD/mmdebstrap.")"'??????????) exit 0;; *) echo "$1"; exit 1;; esac' \
 	 {{ DIST }} /tmp/debian-chroot.tar {{ MIRROR }}
 tar -tf /tmp/debian-chroot.tar | sort | diff -u tar1.txt -
 # use rmdir as a quick check that nothing is remaining in TMPDIR
-runuser -u user -- rmdir "$homedir/$TMPDIR_ADD"
+$prefix rmdir "$homedir/$TMPDIR_ADD"
 rm /tmp/debian-chroot.tar
diff --git a/tests/cwd-directory-not-accessible-by-unshared-user b/tests/cwd-directory-not-accessible-by-unshared-user
index 0bb06c3..5312e01 100644
--- a/tests/cwd-directory-not-accessible-by-unshared-user
+++ b/tests/cwd-directory-not-accessible-by-unshared-user
@@ -1,21 +1,30 @@
 #!/bin/sh
 set -eu
 export LC_ALL=C.UTF-8
-if [ ! -e /mmdebstrap-testenv ]; then
-	echo "this test modifies the system and should only be run inside a container" >&2
-	exit 1
+
+[ "$(id -u)" -eq 0 ]
+[ {{ MODE }} = "unshare" ]
+
+if ! id "${SUDO_USER:-user}" 2>/dev/null; then
+       if [ ! -e /mmdebstrap-testenv ]; then
+               echo "this test modifies the system and should only be run inside a container" >&2
+               exit 1
+       fi
+       useradd --home-dir "/home/${SUDO_USER:-user}" --create-home "${SUDO_USER:-user}"
 fi
-useradd --home-dir /home/user --create-home user
+prefix="runuser -u ${SUDO_USER:-user} --"
+
 mkdir /tmp/debian-chroot
 chmod 700 /tmp/debian-chroot
-chown user:user /tmp/debian-chroot
+chown "${SUDO_USER:-user}:${SUDO_USER:-user}" /tmp/debian-chroot
+set -- env --chdir=/tmp/debian-chroot
 if [ "{{ CMD }}" = "./mmdebstrap" ]; then
-	set -- "$(realpath --canonicalize-existing ./mmdebstrap)"
+	set -- "$@" "$(realpath --canonicalize-existing ./mmdebstrap)"
 elif [ "{{ CMD }}" = "perl -MDevel::Cover=-silent,-nogcov ./mmdebstrap" ]; then
-	set -- perl -MDevel::Cover=-silent,-nogcov "$(realpath --canonicalize-existing ./mmdebstrap)"
+	set -- "$@" perl -MDevel::Cover=-silent,-nogcov "$(realpath --canonicalize-existing ./mmdebstrap)"
 else
-	set -- {{ CMD }}
+	set -- "$@" {{ CMD }}
 fi
-env --chdir=/tmp/debian-chroot runuser -u user -- "$@" --mode=unshare --variant=apt {{ DIST }} /tmp/debian-chroot.tar {{ MIRROR }}
+$prefix "$@" --mode={{ MODE }} --variant=apt {{ DIST }} /tmp/debian-chroot.tar {{ MIRROR }}
 tar -tf /tmp/debian-chroot.tar | sort | diff -u tar1.txt -
 rm /tmp/debian-chroot.tar
diff --git a/tests/dev-ptmx b/tests/dev-ptmx
index f96e204..2636ed4 100644
--- a/tests/dev-ptmx
+++ b/tests/dev-ptmx
@@ -7,15 +7,17 @@ if [ {{ MODE }} != unshare ] && [ {{ MODE }} != root ]; then
 	exit 1
 fi
 
-if [ ! -e /mmdebstrap-testenv ]; then
-	echo "this test modifies the system and should only be run inside a container" >&2
-	exit 1
-fi
-if [ "$(id -u)" -eq 0 ] && ! id -u user > /dev/null 2>&1; then
-	useradd --home-dir /home/user --create-home user
-fi
 prefix=
-[ "$(id -u)" -eq 0 ] && [ "{{ MODE }}" != "root" ] && prefix="runuser -u user --"
+if [ "$(id -u)" -eq 0 ] && [ "{{ MODE }}" != "root" ] && [ "{{ MODE }}" != "auto" ]; then
+	if ! id "${SUDO_USER:-user}" 2>/dev/null; then
+		if [ ! -e /mmdebstrap-testenv ]; then
+			echo "this test modifies the system and should only be run inside a container" >&2
+			exit 1
+		fi
+		useradd --home-dir "/home/${SUDO_USER:-user}" --create-home "${SUDO_USER:-user}"
+	fi
+	prefix="runuser -u ${SUDO_USER:-user} --"
+fi
 
 # this mimics what apt does in apt-pkg/deb/dpkgpm.cc/pkgDPkgPM::StartPtyMagic()
 cat > /tmp/test.c << 'END'
diff --git a/tests/install-doc-debian b/tests/install-doc-debian
index 10bfe8a..12d1084 100644
--- a/tests/install-doc-debian
+++ b/tests/install-doc-debian
@@ -1,16 +1,23 @@
 #!/bin/sh
 set -eu
 export LC_ALL=C.UTF-8
-if [ "$(id -u)" -eq 0 ] && ! id -u user > /dev/null 2>&1; then
-	if [ ! -e /mmdebstrap-testenv ]; then
-		echo "this test modifies the system and should only be run inside a container" >&2
-		exit 1
-	fi
-	useradd --home-dir /home/user --create-home user
-fi
+
+[ {{ VARIANT }} = "custom" ]
+[ {{ MODE }} = "chrootless" ]
+
 prefix=
-[ "$(id -u)" -eq 0 ] && prefix="runuser -u user --"
-$prefix {{ CMD }} --mode=chrootless --variant=custom --include=doc-debian {{ DIST }} /tmp/debian-chroot {{ MIRROR }}
+if [ "$(id -u)" -eq 0 ] && [ "{{ MODE }}" != "root" ] && [ "{{ MODE }}" != "auto" ]; then
+	if ! id "${SUDO_USER:-user}" 2>/dev/null; then
+		if [ ! -e /mmdebstrap-testenv ]; then
+			echo "this test modifies the system and should only be run inside a container" >&2
+			exit 1
+		fi
+		useradd --home-dir "/home/${SUDO_USER:-user}" --create-home "${SUDO_USER:-user}"
+	fi
+	prefix="runuser -u ${SUDO_USER:-user} --"
+fi
+
+$prefix {{ CMD }} --mode={{ MODE }} --variant={{ VARIANT }} --include=doc-debian {{ DIST }} /tmp/debian-chroot {{ MIRROR }}
 tar -C /tmp/debian-chroot --owner=0 --group=0 --numeric-owner --sort=name --clamp-mtime --mtime="$(date --utc --date=@{{ SOURCE_DATE_EPOCH }} --iso-8601=seconds)" -cf /tmp/debian-chroot.tar .
 tar tvf /tmp/debian-chroot.tar > doc-debian.tar.list
 rm /tmp/debian-chroot.tar
diff --git a/tests/install-doc-debian-and-output-tarball b/tests/install-doc-debian-and-output-tarball
index c218d97..c9e0fbb 100644
--- a/tests/install-doc-debian-and-output-tarball
+++ b/tests/install-doc-debian-and-output-tarball
@@ -2,15 +2,22 @@
 set -eu
 export LC_ALL=C.UTF-8
 export SOURCE_DATE_EPOCH={{ SOURCE_DATE_EPOCH }}
-if [ "$(id -u)" -eq 0 ] && ! id -u user > /dev/null 2>&1; then
-	if [ ! -e /mmdebstrap-testenv ]; then
-		echo "this test modifies the system and should only be run inside a container" >&2
-		exit 1
-	fi
-	useradd --home-dir /home/user --create-home user
-fi
+
+[ {{ VARIANT }} = "custom" ]
+[ {{ MODE }} = "chrootless" ]
+
 prefix=
-[ "$(id -u)" -eq 0 ] && prefix="runuser -u user --"
-$prefix {{ CMD }} --mode=chrootless --variant=custom --include=doc-debian {{ DIST }} /tmp/debian-chroot.tar {{ MIRROR }}
+if [ "$(id -u)" -eq 0 ] && [ "{{ MODE }}" != "root" ] && [ "{{ MODE }}" != "auto" ]; then
+	if ! id "${SUDO_USER:-user}" 2>/dev/null; then
+		if [ ! -e /mmdebstrap-testenv ]; then
+			echo "this test modifies the system and should only be run inside a container" >&2
+			exit 1
+		fi
+		useradd --home-dir "/home/${SUDO_USER:-user}" --create-home "${SUDO_USER:-user}"
+	fi
+	prefix="runuser -u ${SUDO_USER:-user} --"
+fi
+
+$prefix {{ CMD }} --mode={{ MODE }} --variant={{ VARIANT }} --include=doc-debian {{ DIST }} /tmp/debian-chroot.tar {{ MIRROR }}
 tar tvf /tmp/debian-chroot.tar | grep -v ' ./dev' | diff -u doc-debian.tar.list -
 rm /tmp/debian-chroot.tar
diff --git a/tests/install-doc-debian-and-test-hooks b/tests/install-doc-debian-and-test-hooks
index bc2efb0..7c1e0c7 100644
--- a/tests/install-doc-debian-and-test-hooks
+++ b/tests/install-doc-debian-and-test-hooks
@@ -2,16 +2,23 @@
 set -eu
 export LC_ALL=C.UTF-8
 export SOURCE_DATE_EPOCH={{ SOURCE_DATE_EPOCH }}
-if [ "$(id -u)" -eq 0 ] && ! id -u user > /dev/null 2>&1; then
-	if [ ! -e /mmdebstrap-testenv ]; then
-		echo "this test modifies the system and should only be run inside a container" >&2
-		exit 1
-	fi
-	useradd --home-dir /home/user --create-home user
-fi
+
+[ {{ VARIANT }} = "custom" ]
+[ {{ MODE }} = "chrootless" ]
+
 prefix=
-[ "$(id -u)" -eq 0 ] && prefix="runuser -u user --"
-$prefix {{ CMD }} --mode=chrootless --skip=cleanup/tmp --variant=custom --include=doc-debian --setup-hook='touch "$1/tmp/setup"' --customize-hook='touch "$1/tmp/customize"' {{ DIST }} /tmp/debian-chroot {{ MIRROR }}
+if [ "$(id -u)" -eq 0 ] && [ "{{ MODE }}" != "root" ] && [ "{{ MODE }}" != "auto" ]; then
+	if ! id "${SUDO_USER:-user}" 2>/dev/null; then
+		if [ ! -e /mmdebstrap-testenv ]; then
+			echo "this test modifies the system and should only be run inside a container" >&2
+			exit 1
+		fi
+		useradd --home-dir "/home/${SUDO_USER:-user}" --create-home "${SUDO_USER:-user}"
+	fi
+	prefix="runuser -u ${SUDO_USER:-user} --"
+fi
+
+$prefix {{ CMD }} --mode={{ MODE }} --skip=cleanup/tmp --variant={{ VARIANT }} --include=doc-debian --setup-hook='touch "$1/tmp/setup"' --customize-hook='touch "$1/tmp/customize"' {{ DIST }} /tmp/debian-chroot {{ MIRROR }}
 rm /tmp/debian-chroot/tmp/setup
 rm /tmp/debian-chroot/tmp/customize
 tar -C /tmp/debian-chroot --owner=0 --group=0 --numeric-owner --sort=name --clamp-mtime --mtime="$(date --utc --date=@{{ SOURCE_DATE_EPOCH }} --iso-8601=seconds)" -cf /tmp/debian-chroot.tar .
diff --git a/tests/install-libmagic-mgc-on-arm64 b/tests/install-libmagic-mgc-on-arm64
index f070f21..a1349a2 100644
--- a/tests/install-libmagic-mgc-on-arm64
+++ b/tests/install-libmagic-mgc-on-arm64
@@ -1,16 +1,23 @@
 #!/bin/sh
 set -eu
 export LC_ALL=C.UTF-8
-if [ "$(id -u)" -eq 0 ] && ! id -u user > /dev/null 2>&1; then
-	if [ ! -e /mmdebstrap-testenv ]; then
-		echo "this test modifies the system and should only be run inside a container" >&2
-		exit 1
-	fi
-	useradd --home-dir /home/user --create-home user
-fi
+
+[ {{ VARIANT }} = "custom" ]
+[ {{ MODE }} = "chrootless" ]
+
 prefix=
-[ "$(id -u)" -eq 0 ] && prefix="runuser -u user --"
-$prefix {{ CMD }} --mode=chrootless --variant=custom --architectures=arm64 --include=libmagic-mgc {{ DIST }} /tmp/debian-chroot {{ MIRROR }}
+if [ "$(id -u)" -eq 0 ] && [ "{{ MODE }}" != "root" ] && [ "{{ MODE }}" != "auto" ]; then
+	if ! id "${SUDO_USER:-user}" 2>/dev/null; then
+		if [ ! -e /mmdebstrap-testenv ]; then
+			echo "this test modifies the system and should only be run inside a container" >&2
+			exit 1
+		fi
+		useradd --home-dir "/home/${SUDO_USER:-user}" --create-home "${SUDO_USER:-user}"
+	fi
+	prefix="runuser -u ${SUDO_USER:-user} --"
+fi
+
+$prefix {{ CMD }} --mode={{ MODE }} --variant={{ VARIANT }} --architectures=arm64 --include=libmagic-mgc {{ DIST }} /tmp/debian-chroot {{ MIRROR }}
 # delete contents of libmagic-mgc
 rm /tmp/debian-chroot/usr/lib/file/magic.mgc
 rm /tmp/debian-chroot/usr/share/doc/libmagic-mgc/README.Debian
diff --git a/tests/jessie-or-older b/tests/jessie-or-older
index 6538563..a624547 100644
--- a/tests/jessie-or-older
+++ b/tests/jessie-or-older
@@ -1,15 +1,30 @@
 #!/bin/sh
 set -eu
 export LC_ALL=C.UTF-8
-if [ ! -e /mmdebstrap-testenv ]; then
-	echo "this test modifies the system and should only be run inside a container" >&2
-	exit 1
-fi
-useradd --home-dir /home/user --create-home user
 export SOURCE_DATE_EPOCH={{ SOURCE_DATE_EPOCH }}
 
+trap "rm -f /tmp/debian-chroot-{{ MODE }}.tar /tmp/debian-chroot-root-normal.tar" EXIT INT TERM
+
+[ "$(id -u)" -eq 0 ]
+
+prefix=
+if [ "$(id -u)" -eq 0 ] && [ "{{ MODE }}" != "root" ] && [ "{{ MODE }}" != "auto" ]; then
+	if ! id "${SUDO_USER:-user}" 2>/dev/null; then
+		if [ ! -e /mmdebstrap-testenv ]; then
+			echo "this test modifies the system and should only be run inside a container" >&2
+			exit 1
+		fi
+		useradd --home-dir "/home/${SUDO_USER:-user}" --create-home "${SUDO_USER:-user}"
+	fi
+	prefix="runuser -u ${SUDO_USER:-user} --"
+fi
+
+MMTARFILTER=
+[ -x /usr/bin/mmtarfilter ] && MMTARFILTER=/usr/bin/mmtarfilter
+[ -x ./tarfilter ] && MMTARFILTER=./tarfilter
+
 filter() {
-	./tarfilter \
+	"$MMTARFILTER" \
 		--path-exclude=/usr/bin/uncompress \
 		--path-exclude=/var/cache/debconf/config.dat-old \
 		--path-exclude=/var/cache/debconf/templates.dat-old \
@@ -20,19 +35,7 @@ filter() {
 }
 
 # base for comparison without jessie-or-older hook
-{{ CMD }} --mode=root --variant={{ VARIANT }} {{ DIST }} - {{ MIRROR }} | filter > /tmp/debian-chroot-root-normal.tar
+{{ CMD }} --mode=root --variant={{ VARIANT }} {{ DIST }} - {{ MIRROR }} > /tmp/debian-chroot-root-normal.tar
 
-# root
-{{ CMD }} --mode=root --variant={{ VARIANT }} --hook-dir=./hooks/jessie-or-older {{ DIST }} - {{ MIRROR }} | filter > /tmp/debian-chroot-root.tar
-cmp /tmp/debian-chroot-root-normal.tar /tmp/debian-chroot-root.tar
-rm /tmp/debian-chroot-root.tar
-# unshare
-runuser -u user -- {{ CMD }} --mode=unshare --variant={{ VARIANT }} --hook-dir=./hooks/jessie-or-older {{ DIST }} - {{ MIRROR }} | filter > /tmp/debian-chroot-unshare.tar
-cmp /tmp/debian-chroot-root-normal.tar /tmp/debian-chroot-unshare.tar
-rm /tmp/debian-chroot-unshare.tar
-# fakechroot
-runuser -u user -- {{ CMD }} --mode=fakechroot --variant={{ VARIANT }} --hook-dir=./hooks/jessie-or-older {{ DIST }} - {{ MIRROR }} | filter > /tmp/debian-chroot-fakechroot.tar
-cmp /tmp/debian-chroot-root-normal.tar /tmp/debian-chroot-fakechroot.tar
-rm /tmp/debian-chroot-fakechroot.tar
-
-rm /tmp/debian-chroot-root-normal.tar
+$prefix {{ CMD }} --mode={{ MODE }} --variant={{ VARIANT }} --hook-dir=./hooks/jessie-or-older {{ DIST }} - {{ MIRROR }} | filter > /tmp/debian-chroot-{{ MODE }}.tar
+filter < /tmp/debian-chroot-root-normal.tar | cmp - /tmp/debian-chroot-{{ MODE }}.tar
diff --git a/tests/missing-dev-sys-proc-inside-the-chroot b/tests/missing-dev-sys-proc-inside-the-chroot
index 7007d09..91cced3 100644
--- a/tests/missing-dev-sys-proc-inside-the-chroot
+++ b/tests/missing-dev-sys-proc-inside-the-chroot
@@ -1,9 +1,20 @@
 #!/bin/sh
 set -eu
 export LC_ALL=C.UTF-8
-if [ ! -e /mmdebstrap-testenv ]; then
-	echo "this test modifies the system and should only be run inside a container" >&2
-	exit 1
+
+[ {{ MODE }} = "unshare" ]
+[ {{ VARIANT }} = "custom" ]
+
+prefix=
+if [ "$(id -u)" -eq 0 ] && [ "{{ MODE }}" != "root" ] && [ "{{ MODE }}" != "auto" ]; then
+	if ! id "${SUDO_USER:-user}" 2>/dev/null; then
+		if [ ! -e /mmdebstrap-testenv ]; then
+			echo "this test modifies the system and should only be run inside a container" >&2
+			exit 1
+		fi
+		useradd --home-dir "/home/${SUDO_USER:-user}" --create-home "${SUDO_USER:-user}"
+	fi
+	prefix="runuser -u ${SUDO_USER:-user} --"
 fi
-useradd --home-dir /home/user --create-home user
-runuser -u user -- {{ CMD }} --mode=unshare --variant=custom --include=dpkg,dash,diffutils,coreutils,libc-bin,sed {{ DIST }} /dev/null {{ MIRROR }}
+
+$prefix {{ CMD }} --mode={{ MODE }} --variant={{ VARIANT }} --include=dpkg,dash,diffutils,coreutils,libc-bin,sed {{ DIST }} /dev/null {{ MIRROR }}
diff --git a/tests/no-sbin-in-path b/tests/no-sbin-in-path
index abceb23..f101b1e 100644
--- a/tests/no-sbin-in-path
+++ b/tests/no-sbin-in-path
@@ -7,16 +7,22 @@
 
 set -eu
 export LC_ALL=C.UTF-8
-[ "{{ MODE }}" = "fakechroot" ]
+
 trap "rm -f /tmp/debian-chroot.tar" EXIT INT TERM
-if [ "$(id -u)" -eq 0 ] && ! id -u user > /dev/null 2>&1; then
-	if [ ! -e /mmdebstrap-testenv ]; then
-		echo "this test modifies the system and should only be run inside a container" >&2
-		exit 1
-	fi
-	useradd --home-dir /home/user --create-home user
-fi
+
+[ "{{ MODE }}" = "fakechroot" ]
+
 prefix=
-[ "$(id -u)" -eq 0 ] && prefix="runuser -u user --"
-$prefix env PATH=/usr/bin:/bin fakechroot fakeroot {{ CMD }} --mode=fakechroot --variant=apt {{ DIST }} /tmp/debian-chroot.tar {{ MIRROR }}
+if [ "$(id -u)" -eq 0 ] && [ "{{ MODE }}" != "root" ] && [ "{{ MODE }}" != "auto" ]; then
+	if ! id "${SUDO_USER:-user}" 2>/dev/null; then
+		if [ ! -e /mmdebstrap-testenv ]; then
+			echo "this test modifies the system and should only be run inside a container" >&2
+			exit 1
+		fi
+		useradd --home-dir "/home/${SUDO_USER:-user}" --create-home "${SUDO_USER:-user}"
+	fi
+	prefix="runuser -u ${SUDO_USER:-user} --"
+fi
+
+$prefix env PATH=/usr/bin:/bin fakechroot fakeroot {{ CMD }} --mode={{ MODE }} --variant=apt {{ DIST }} /tmp/debian-chroot.tar {{ MIRROR }}
 tar -tf /tmp/debian-chroot.tar | sort | diff -u tar1.txt -
diff --git a/tests/pivot_root b/tests/pivot_root
index b6a0947..f51e221 100644
--- a/tests/pivot_root
+++ b/tests/pivot_root
@@ -4,17 +4,17 @@ export LC_ALL=C.UTF-8
 export SOURCE_DATE_EPOCH={{ SOURCE_DATE_EPOCH }}
 trap "rm -f /tmp/chroot1.tar /tmp/chroot2.tar /tmp/chroot3.tar /tmp/mmdebstrap" EXIT INT TERM
 
-if [ ! -e /mmdebstrap-testenv ]; then
-	echo "this test modifies the system and should only be run inside a container" >&2
-	exit 1
-fi
-
-if [ "$(id -u)" -eq 0 ] && ! id -u user > /dev/null 2>&1; then
-	useradd --home-dir /home/user --create-home user
-fi
-
 prefix=
-[ "$(id -u)" -eq 0 ] && [ "{{ MODE }}" != "root" ] && prefix="runuser -u user --"
+if [ "$(id -u)" -eq 0 ] && [ "{{ MODE }}" != "root" ] && [ "{{ MODE }}" != "auto" ]; then
+	if ! id "${SUDO_USER:-user}" 2>/dev/null; then
+		if [ ! -e /mmdebstrap-testenv ]; then
+			echo "this test modifies the system and should only be run inside a container" >&2
+			exit 1
+		fi
+		useradd --home-dir "/home/${SUDO_USER:-user}" --create-home "${SUDO_USER:-user}"
+	fi
+	prefix="runuser -u ${SUDO_USER:-user} --"
+fi
 
 MMDEBSTRAP=
 [ -e /usr/bin/mmdebstrap ] && MMDEBSTRAP=/usr/bin/mmdebstrap
diff --git a/tests/root-mode-inside-unshare-chroot b/tests/root-mode-inside-unshare-chroot
index 461de27..634cca0 100644
--- a/tests/root-mode-inside-unshare-chroot
+++ b/tests/root-mode-inside-unshare-chroot
@@ -5,13 +5,22 @@
 
 set -eu
 export LC_ALL=C.UTF-8
-if [ ! -e /mmdebstrap-testenv ]; then
-	echo "this test modifies the system and should only be run inside a container" >&2
-	exit 1
+
+[ {{ MODE }} = "unshare" ]
+
+prefix=
+if [ "$(id -u)" -eq 0 ] && [ "{{ MODE }}" != "root" ] && [ "{{ MODE }}" != "auto" ]; then
+	if ! id "${SUDO_USER:-user}" 2>/dev/null; then
+		if [ ! -e /mmdebstrap-testenv ]; then
+			echo "this test modifies the system and should only be run inside a container" >&2
+			exit 1
+		fi
+		useradd --home-dir "/home/${SUDO_USER:-user}" --create-home "${SUDO_USER:-user}"
+	fi
+	prefix="runuser -u ${SUDO_USER:-user} --"
 fi
-[ "$(whoami)" = "root" ]
-useradd --home-dir /home/user --create-home user
-cat << 'SCRIPT' > script.sh
+
+cat << 'SCRIPT' > /tmp/script.sh
 #!/bin/sh
 set -eu
 rootfs="$1"
@@ -22,10 +31,10 @@ chroot "$rootfs" env --chdir=/mnt \
 	{{ CMD }} --mode=root --variant=apt \
 	{{ DIST }} /tmp/debian-chroot.tar {{ MIRROR }}
 SCRIPT
-chmod +x script.sh
-runuser -u user -- {{ CMD }} --mode=unshare --variant=apt --include=perl,mount \
-	--customize-hook=./script.sh \
+chmod +x /tmp/script.sh
+$prefix {{ CMD }} --mode={{ MODE }} --variant=apt --include=perl,mount \
+	--customize-hook=/tmp/script.sh \
 	--customize-hook="download /tmp/debian-chroot.tar /tmp/debian-chroot.tar" \
 	{{ DIST }} /dev/null {{ MIRROR }}
 tar -tf /tmp/debian-chroot.tar | sort | diff -u tar1.txt -
-rm /tmp/debian-chroot.tar script.sh
+rm /tmp/debian-chroot.tar /tmp/script.sh
diff --git a/tests/special-hooks-with-mode-mode b/tests/special-hooks-with-mode-mode
index 60d5d85..b8b9b39 100644
--- a/tests/special-hooks-with-mode-mode
+++ b/tests/special-hooks-with-mode-mode
@@ -1,15 +1,19 @@
 #!/bin/sh
 set -eu
 export LC_ALL=C.UTF-8
-if [ "$(id -u)" -eq 0 ] && ! id -u user > /dev/null 2>&1; then
-	if [ ! -e /mmdebstrap-testenv ]; then
-		echo "this test modifies the system and should only be run inside a container" >&2
-		exit 1
-	fi
-	useradd --home-dir /home/user --create-home user
-fi
+
 prefix=
-[ "$(id -u)" -eq 0 ] && [ "{{ MODE }}" != "root" ] && prefix="runuser -u user --"
+if [ "$(id -u)" -eq 0 ] && [ "{{ MODE }}" != "root" ] && [ "{{ MODE }}" != "auto" ]; then
+	if ! id "${SUDO_USER:-user}" 2>/dev/null; then
+		if [ ! -e /mmdebstrap-testenv ]; then
+			echo "this test modifies the system and should only be run inside a container" >&2
+			exit 1
+		fi
+		useradd --home-dir "/home/${SUDO_USER:-user}" --create-home "${SUDO_USER:-user}"
+	fi
+	prefix="runuser -u ${SUDO_USER:-user} --"
+fi
+
 [ "{{ MODE }}" = "fakechroot" ] && prefix="$prefix fakechroot fakeroot"
 symlinktarget=/real
 [ "{{ MODE }}" = "fakechroot" ] && symlinktarget='$1/real'
diff --git a/tests/unpack-doc-debian b/tests/unpack-doc-debian
index cbf2bbd..cc48fa8 100644
--- a/tests/unpack-doc-debian
+++ b/tests/unpack-doc-debian
@@ -1,17 +1,23 @@
 #!/bin/sh
 set -eu
 export LC_ALL=C.UTF-8
-if [ "$(id -u)" -eq 0 ] && ! id -u user > /dev/null 2>&1; then
-	if [ ! -e /mmdebstrap-testenv ]; then
-		echo "this test modifies the system and should only be run inside a container" >&2
-		exit 1
-	fi
-	useradd --home-dir /home/user --create-home user
-fi
+
+[ {{ VARIANT }} = extract ]
+
 prefix=
-[ "$(id -u)" -eq 0 ] && [ "{{ MODE }}" != "root" ] && prefix="runuser -u user --"
+if [ "$(id -u)" -eq 0 ] && [ "{{ MODE }}" != "root" ] && [ "{{ MODE }}" != "auto" ]; then
+	if ! id "${SUDO_USER:-user}" 2>/dev/null; then
+		if [ ! -e /mmdebstrap-testenv ]; then
+			echo "this test modifies the system and should only be run inside a container" >&2
+			exit 1
+		fi
+		useradd --home-dir "/home/${SUDO_USER:-user}" --create-home "${SUDO_USER:-user}"
+	fi
+	prefix="runuser -u ${SUDO_USER:-user} --"
+fi
+
 [ "{{ MODE }}" = "fakechroot" ] && prefix="$prefix fakechroot fakeroot"
-$prefix {{ CMD }} --mode={{ MODE }} --variant=extract --include=doc-debian {{ DIST }} /tmp/debian-chroot {{ MIRROR }}
+$prefix {{ CMD }} --mode={{ MODE }} --variant={{ VARIANT }} --include=doc-debian {{ DIST }} /tmp/debian-chroot {{ MIRROR }}
 # delete contents of doc-debian
 rm /tmp/debian-chroot/usr/share/doc-base/debian-*
 rm -r /tmp/debian-chroot/usr/share/doc/debian
diff --git a/tests/unshare-include-deb b/tests/unshare-include-deb
index 6cca99d..a4daaf9 100644
--- a/tests/unshare-include-deb
+++ b/tests/unshare-include-deb
@@ -5,14 +5,17 @@ export LC_ALL=C.UTF-8
 
 [ "{{ MODE }}" = unshare ]
 
-if [ "$(id -u)" -eq 0 ] && ! id -u user > /dev/null 2>&1; then
-	if [ ! -e /mmdebstrap-testenv ]; then
-		echo "this test modifies the system and should only be run inside a container" >&2
-		exit 1
+prefix=
+if [ "$(id -u)" -eq 0 ] && [ "{{ MODE }}" != "root" ] && [ "{{ MODE }}" != "auto" ]; then
+	if ! id "${SUDO_USER:-user}" 2>/dev/null; then
+		if [ ! -e /mmdebstrap-testenv ]; then
+			echo "this test modifies the system and should only be run inside a container" >&2
+			exit 1
+		fi
+		useradd --home-dir "/home/${SUDO_USER:-user}" --create-home "${SUDO_USER:-user}"
 	fi
-	useradd --home-dir /home/user --create-home user
+	prefix="runuser -u ${SUDO_USER:-user} --"
 fi
-[ "$(id -u)" -eq 0 ] && prefix="runuser -u user --"
 
 # instead of obtaining a .deb from our cache, we create a new package because
 # otherwise apt might decide to download the package with the same name and