test: rewrite udev-test.pl in Python

I tried to keep this a 1:1 rewrite with the same field names.
Nevertheless, some changes were made:
- exp_add_error and exp_rem_error are dropped. Those fields meant that
  "./test-udev add <devpath>" actually succeeded, but symlinks were not
  created, and exp_links was ignored and could contain bogus content.
  Instead, exp_links and not_exp_links are adjusted to not contain
  garbage and the tests check that "./test-udev add" succeeds and that
  the links are as expected from exp_links and not_exp_links.
- cleanup was only used in one rule, and that rule was expected to fail,
  so cleanup wasn't actually necessary. So the cleanup field and the
  logic to call cleanup from individual tests is removed.
- a bunch of fields were set, but didn't seem to be connected to any
  implementation: not_exp_name, not_exp_test.
  e62acc3159935781f05fa59c48e5a74e85c61ce2 did a rewrite of some of the
  tests and it seems that not_exp_test was added by mistake and
  not_exp_name was left behind by mistake.
  In Python, the field list is declared in the class, so it's harder to
  assign an unused attribute. Those uses were converted to not_exp_links.
- in most rules, r"""…""" is used, so that escaping is not necessary.
- the logic to generate devices was only used in one place, and the
  generator function also had provisions to handle arguments that were
  never given. all_block_devs() is made much simpler.
- Descriptions that started with a capital letter were shortened
  and lowercased.
- no special test case counting is done. pytest just counts the cases
  (Rules objects).
- the output for failures is also removed. If something goes wrong, the
  user can use pytest --pdb or such to debug the issue.
- perl version used a semaphore to manage udev runners, and would fork,
  optionally wait a bit, and then start the runner. In the python
  version, we just spawn them all and wait for them to exit. It's not
  very convenient to call fork() from python, so instead the runner
  was modified (in previous commit) to wait.

The test can be called as:
  (cd build && sudo pytest -v ../test/udev-test.py)
  sudo meson test -C build udev-test.py -v

I think this generally provides functionality that is close to the perl
version. It seems some of the checks are now more fully implemented.
Support for strace/gdb/valgrind is missing.

Runtime goes down: 8.36 s → 5.78 s.

2 files changed, 2416 insertions, 1 deletions

diff --git a/test/meson.build b/test/meson.build
index b9992fae47..6af112d141 100644
--- a/test/meson.build
+++ b/test/meson.build
@@ -134,7 +134,7 @@ custom_target(
 if perl.found()
         udev_test_pl = find_program('udev-test.pl')
         if want_tests != 'false'
-                test('udev-test',
+                test('udev-test.pl',
                      udev_test_pl,
                      timeout : 180)
         endif
@@ -142,6 +142,13 @@ else
         message('Skipping udev-test because perl is not available')
 endif
 
+if want_tests != 'false'
+        test('udev-test.py',
+             files('udev-test.py'),
+             args : ['-v'],
+             timeout : 180)
+endif
+
 ############################################################
 
 rpm = find_program('rpm', required : false)
diff --git a/test/udev-test.py b/test/udev-test.py
new file mode 100755
index 0000000000..5ddda3865f
--- /dev/null
+++ b/test/udev-test.py
@@ -0,0 +1,2408 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: LGPL-2.1-or-later
+
+# pylint: disable=missing-docstring,redefined-outer-name,invalid-name
+# pylint: disable=unspecified-encoding,no-else-return,line-too-long,too-many-lines
+# pylint: disable=multiple-imports,too-many-instance-attributes,consider-using-with
+
+# udev test
+#
+# Provides automated testing of the udev binary.
+# The whole test is self contained in this file, except the matching sysfs tree.
+# Simply extend RULES to add a new test.
+#
+# Every test is driven by its own temporary config file.
+# This program prepares the environment, creates the config and calls udev.
+#
+# udev parses the rules, looks at the provided sysfs and first creates and then
+# removes the device node. After creation and removal the result is checked
+# against the expected value and the result is printed.
+
+import dataclasses
+import functools
+import os
+import pwd, grp
+import re
+import stat
+import subprocess
+import sys
+import textwrap
+from pathlib import Path
+from typing import Optional
+
+try:
+    import pytest
+except ImportError as e:
+    print(str(e), file=sys.stderr)
+    sys.exit(77)
+
+
+# TODO: pass path to test-udev from outside
+UDEV_BIN       = './test-udev'
+UDEV_RUN       = Path('test/run')
+UDEV_RULES_DIR = UDEV_RUN / 'udev/rules.d'
+UDEV_RULES     = UDEV_RULES_DIR / 'udev-test.rules'
+
+UDEV_RUN       = Path('test/run')
+UDEV_TMPFS     = Path('test/tmpfs')
+UDEV_DEV       = UDEV_TMPFS / 'dev'
+UDEV_SYS       = UDEV_TMPFS / 'sys'
+
+# Relax sd-device's sysfs verification, since we want to provide a fake sysfs
+# here that actually is a tmpfs.
+os.environ['SYSTEMD_DEVICE_VERIFY_SYSFS'] = '0'
+
+rules_10k_tags = \
+    '\n'.join(f'KERNEL=="sda", TAG+="test{i + 1}"'
+              for i in range(10_000))
+
+rules_10k_tags_continuation = \
+    ',\\\n'.join(('KERNEL=="sda"',
+                  *(f'TAG+="test{i + 1}"' for i in range(10_000))))
+
+@dataclasses.dataclass
+class Device:
+    devpath: str
+    devnode: Optional[str] = None
+    exp_links: Optional[list[str]] = None
+    not_exp_links: Optional[list[str]] = None
+
+    exp_perms: Optional[int] = None
+    exp_major_minor: Optional[str] = None
+
+    def check_permissions(self, st: os.stat_result) -> None:
+        if self.exp_perms is None:
+            return
+
+        user, group, mode = self.exp_perms.split(':')
+
+        if user:
+            try:
+                uid = pwd.getpwnam(user).pw_uid
+            except KeyError:
+                uid = int(user)
+            assert uid == st.st_uid
+
+        if group:
+            try:
+                gid = grp.getgrnam(group).gr_gid
+            except KeyError:
+                gid = int(group)
+            assert gid == st.st_gid
+
+        if mode:
+            mode = int(mode, 8)
+            assert stat.S_IMODE(st.st_mode) == mode
+
+    def check_major_minor(self, st: os.stat_result) -> None:
+        if not self.exp_major_minor:
+            return
+        minor, major = (int(x) for x in self.exp_major_minor.split(':'))
+        assert st.st_rdev == os.makedev(minor, major)
+
+    def get_devnode(self) -> Path:
+        suffix = self.devnode if self.devnode else self.devpath.split('/')[-1]
+        return UDEV_DEV / suffix
+
+    def check_link_add(self, link: str, devnode: Path) -> None:
+        link = UDEV_DEV / link
+        tgt = link.parent / link.readlink()
+        assert devnode.samefile(tgt)
+
+    def check_link_nonexistent(self, link: str, devnode: Path) -> None:
+        link = UDEV_DEV / link
+
+        try:
+            tgt = link.parent / link.readlink()
+        except FileNotFoundError:
+            return
+
+        assert not devnode.samefile(tgt)
+
+    def check_add(self) -> None:
+        print(f'check_add {self.devpath}')
+
+        devnode = self.get_devnode()
+        st = devnode.stat(follow_symlinks=False)
+        assert stat.S_ISCHR(st.st_mode) or stat.S_ISBLK(st.st_mode)
+        self.check_permissions(st)
+        self.check_major_minor(st)
+
+        for link in self.exp_links or []:
+            self.check_link_add(link, devnode)
+
+        for link in self.not_exp_links or []:
+            self.check_link_nonexistent(link, devnode)
+
+    def check_link_remove(self, link: str) -> None:
+        link = UDEV_DEV / link
+        with pytest.raises(FileNotFoundError):
+            link.readlink()
+
+    def check_remove(self) -> None:
+        devnode = self.get_devnode()
+        assert not devnode.exists()
+
+        for link in self.exp_links or []:
+            self.check_link_remove(link)
+
+
+def listify(f):
+    def wrap(*args, **kwargs):
+        return list(f(*args, **kwargs))
+    return functools.update_wrapper(wrap, f)
+
+@listify
+def all_block_devs(exp_func) -> list[Device]:
+    # Create a device list with all block devices under /sys
+    # (except virtual devices and cd-roms)
+    # the optional argument exp_func returns expected and non-expected
+    # symlinks for the device.
+
+    for p in UDEV_SYS.glob('dev/block/*'):
+        tgt = os.readlink(p)
+        if re.search('/virtual/ | /sr[0-9]*$', tgt, re.VERBOSE):
+            continue
+
+        assert tgt.startswith('../../')
+        tgt = tgt[5:]
+
+        exp, not_exp = exp_func(tgt)
+        yield Device(devpath=tgt,
+                     exp_links=exp,
+                     not_exp_links=not_exp)
+
+
+@dataclasses.dataclass
+class Rules:
+    desc: str
+    devices: list[Device]
+    rules: str
+    repeat: int = 1
+    delay: Optional[int] = None
+
+    @classmethod
+    def new(cls, desc: str, *devices, rules = None, **kwargs):
+        assert rules.startswith('\n')
+        rules = textwrap.dedent(rules[1:]) if rules else ''
+        return cls(desc, devices, rules, **kwargs)
+
+    def create_rules_file(self) -> None:
+        # create temporary rules
+        UDEV_RULES.parent.mkdir(exist_ok=True, parents=True)
+        UDEV_RULES.write_text(self.rules)
+
+RULES = [
+    Rules.new(
+        'no rules',
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+        ),
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1",
+        ),
+        rules = r"""
+        #
+        """),
+
+    Rules.new(
+        'label test of scsi disc',
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links = ["boot_disk"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA", SYMLINK+="boot_disk%n"
+        KERNEL=="ttyACM0", SYMLINK+="modem"
+        """),
+
+    Rules.new(
+        "label test of scsi disc",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links = ["boot_disk"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA", SYMLINK+="boot_disk%n"
+        KERNEL=="ttyACM0", SYMLINK+="modem"
+        """),
+
+    Rules.new(
+        "label test of scsi disc",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links = ["boot_disk"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA", SYMLINK+="boot_disk%n"
+        KERNEL=="ttyACM0", SYMLINK+="modem"
+        """),
+
+    Rules.new(
+        "label test of scsi partition",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1",
+            exp_links = ["boot_disk1"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA", SYMLINK+="boot_disk%n"
+        """),
+
+    Rules.new(
+        "label test of pattern match",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1",
+            exp_links     = ["boot_disk1", "boot_disk1-4", "boot_disk1-5"],
+            not_exp_links = ["boot_disk1-1", "boot_disk1-2", "boot_disk1-3", "boot_disk1-6", "boot_disk1-7"],
+        ),
+
+        rules = r"""
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="?ATA", SYMLINK+="boot_disk%n-1"
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA?", SYMLINK+="boot_disk%n-2"
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="A??", SYMLINK+="boot_disk%n"
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATAS", SYMLINK+="boot_disk%n-3"
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="AT?", SYMLINK+="boot_disk%n-4"
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="??A", SYMLINK+="boot_disk%n-5"
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA", GOTO="skip-6"
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA", SYMLINK+="boot_disk%n-6"
+        LABEL="skip-6"
+        SUBSYSTEMS=="scsi", GOTO="skip-7"
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA", SYMLINK+="boot_disk%n-7"
+        LABEL="skip-7"
+        """),
+
+    Rules.new(
+        "label test of multiple sysfs files",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1",
+            exp_links       = ["boot_disk1"],
+            not_exp_links   = ["boot_diskX1"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA", ATTRS{model}=="ST910021AS X ", SYMLINK+="boot_diskX%n"
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA", ATTRS{model}=="ST910021AS", SYMLINK+="boot_disk%n"
+        """),
+
+    Rules.new(
+        "label test of max sysfs files (skip invalid rule)",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1",
+            exp_links       = ["boot_disk1", "boot_diskXY1"],
+            not_exp_links   = ["boot_diskXX1"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA", ATTRS{model}=="ST910021AS", ATTRS{scsi_level}=="6", ATTRS{rev}=="4.06", ATTRS{type}=="0", ATTRS{queue_depth}=="32", SYMLINK+="boot_diskXX%n"
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA", ATTRS{model}=="ST910021AS", ATTRS{scsi_level}=="6", ATTRS{rev}=="4.06", ATTRS{type}=="0", ATTRS{queue_depth}=="1", SYMLINK+="boot_diskXY%n"
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA", ATTRS{model}=="ST910021AS", ATTRS{scsi_level}=="6", ATTRS{rev}=="4.06", ATTRS{type}=="0", SYMLINK+="boot_disk%n"
+        """),
+
+    Rules.new(
+        "SYMLINK tests",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1",
+            exp_links       = ["link1", "link2/foo", "link3/aaa/bbb",
+                               "abs1", "abs2/foo", "abs3/aaa/bbb",
+                               "default___replace_test/foo_aaa",
+                               "string_escape___replace/foo_bbb",
+                               "env_with_space",
+                               "default/replace/mode_foo__hoge",
+                               "replace_env_harder_foo__hoge",
+                               "match", "unmatch"],
+            not_exp_links   = ["removed1", "removed2", "removed3", "unsafe/../../path", "/nondev/path/will/be/refused"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA", ATTRS{model}=="ST910021AS", SYMLINK+="removed1"
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA", ATTRS{model}=="ST910021AS", SYMLINK-="removed1"
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA", ATTRS{model}=="ST910021AS", SYMLINK+="/./dev///removed2"
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA", ATTRS{model}=="ST910021AS", SYMLINK-="removed2"
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA", ATTRS{model}=="ST910021AS", SYMLINK+="././removed3"
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA", ATTRS{model}=="ST910021AS", SYMLINK-="/dev//./removed3/./"
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA", ATTRS{model}=="ST910021AS", SYMLINK+="unsafe/../../path"
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA", ATTRS{model}=="ST910021AS", SYMLINK+="/nondev/path/will/be/refused"
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA", ATTRS{model}=="ST910021AS", SYMLINK+="link1 .///link2/././/foo//./ .///link3/aaa/bbb"
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA", ATTRS{model}=="ST910021AS", SYMLINK+="/dev/abs1 /dev//./abs2///foo/./ ////dev/abs3/aaa/bbb"
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA", ATTRS{model}=="ST910021AS", SYMLINK+="default?;;replace%%test/foo'aaa"
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA", ATTRS{model}=="ST910021AS", OPTIONS="string_escape=replace", SYMLINK+="string_escape   replace/foo%%bbb"
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA", ATTRS{model}=="ST910021AS", ENV{.HOGE}="env    with    space", SYMLINK+="%E{.HOGE}"
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA", ATTRS{model}=="ST910021AS", ENV{.HOGE}="default/replace/mode?foo;;hoge", SYMLINK+="%E{.HOGE}"
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA", ATTRS{model}=="ST910021AS", OPTIONS="string_escape=replace", ENV{.HOGE}="replace/env/harder?foo;;hoge", SYMLINK+="%E{.HOGE}"
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA", ATTRS{model}=="ST910021AS", SYMLINK=="link1", SYMLINK+="match"
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA", ATTRS{model}=="ST910021AS", SYMLINK!="removed1", SYMLINK+="unmatch"
+        """),
+
+    Rules.new(
+        "catch device by *",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["modem/0", "catch-all"],
+        ),
+        rules = r"""
+        KERNEL=="ttyACM*", SYMLINK+="modem/%n"
+        KERNEL=="*", SYMLINK+="catch-all"
+        """),
+
+    Rules.new(
+        "catch device by * - take 2",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["modem/0"],
+            not_exp_links   = ["bad"],
+        ),
+        rules = r"""
+        KERNEL=="*ACM1", SYMLINK+="bad"
+        KERNEL=="*ACM0", SYMLINK+="modem/%n"
+        """),
+
+    Rules.new(
+        "catch device by ?",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["modem/0"],
+            not_exp_links   = ["modem/0-1", "modem/0-2"],
+        ),
+        rules = r"""
+        KERNEL=="ttyACM??*", SYMLINK+="modem/%n-1"
+        KERNEL=="ttyACM??", SYMLINK+="modem/%n-2"
+        KERNEL=="ttyACM?", SYMLINK+="modem/%n"
+        """),
+
+    Rules.new(
+        "catch device by character class",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["modem/0"],
+            not_exp_links   = ["modem/0-1", "modem/0-2"],
+        ),
+        rules = r"""
+        KERNEL=="ttyACM[A-Z]*", SYMLINK+="modem/%n-1"
+        KERNEL=="ttyACM?[0-9]", SYMLINK+="modem/%n-2"
+        KERNEL=="ttyACM[0-9]*", SYMLINK+="modem/%n"
+        """),
+
+    Rules.new(
+        "don't replace kernel name",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["modem"],
+        ),
+        rules = r"""
+        KERNEL=="ttyACM0", SYMLINK+="modem"
+        """),
+
+    Rules.new(
+        "comment lines in config file (and don't replace kernel name)",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["modem"],
+        ),
+        rules = r"""
+        # this is a comment
+        KERNEL=="ttyACM0", SYMLINK+="modem"
+
+        """),
+
+    Rules.new(
+        "comment lines in config file with whitespace (and don't replace kernel name)",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["modem"],
+        ),
+        rules = r"""
+         # this is a comment with whitespace before the comment
+        KERNEL=="ttyACM0", SYMLINK+="modem"
+
+        """),
+
+    Rules.new(
+        "whitespace only lines (and don't replace kernel name)",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["whitespace"],
+        ),
+        rules = r"""
+
+
+
+         # this is a comment with whitespace before the comment
+        KERNEL=="ttyACM0", SYMLINK+="whitespace"
+
+
+
+        """),
+
+    Rules.new(
+        "empty lines in config file (and don't replace kernel name)",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["modem"],
+        ),
+        rules = r"""
+
+        KERNEL=="ttyACM0", SYMLINK+="modem"
+
+        """),
+
+    Rules.new(
+        "backslashed multi lines in config file (and don't replace kernel name)",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["modem"],
+        ),
+        rules = r"""
+        KERNEL=="ttyACM0", \
+        SYMLINK+="modem"
+
+        """),
+
+    Rules.new(
+        "preserve backslashes, if they are not for a newline",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["aaa"],
+        ),
+        rules = r"""
+        KERNEL=="ttyACM0", PROGRAM=="/bin/echo -e \101", RESULT=="A", SYMLINK+="aaa"
+        """),
+
+    Rules.new(
+        "stupid backslashed multi lines in config file (and don't replace kernel name)",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["modem"],
+        ),
+        rules = r"""
+
+        #
+        \
+
+        \
+
+        #\
+
+        KERNEL=="ttyACM0", \
+                SYMLINK+="modem"
+
+        """),
+
+    Rules.new(
+        "subdirectory handling",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["sub/direct/ory/modem"],
+        ),
+        rules = r"""
+        KERNEL=="ttyACM0", SYMLINK+="sub/direct/ory/modem"
+        """),
+
+    Rules.new(
+        "parent device name match of scsi partition",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda5",
+            exp_links       = ["first_disk5"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNELS=="0:0:0:0", SYMLINK+="first_disk%n"
+        """),
+
+    Rules.new(
+        "test substitution chars",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda5",
+            exp_links       = ["Major:8:minor:5:kernelnumber:5:id:0:0:0:0"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNELS=="0:0:0:0", SYMLINK+="Major:%M:minor:%m:kernelnumber:%n:id:%b"
+        """),
+
+    Rules.new(
+        "import of shell-value returned from program",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["node12345678"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", IMPORT{program}="/bin/echo -e ' TEST_KEY=12345678\n  TEST_key2=98765'", SYMLINK+="node$env{TEST_KEY}"
+        KERNEL=="ttyACM0", SYMLINK+="modem"
+        """),
+
+    Rules.new(
+        "substitution of sysfs value (%s{file})",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["disk-ATA-sda"],
+            not_exp_links   = ["modem"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA", SYMLINK+="disk-%s{vendor}-%k"
+        KERNEL=="ttyACM0", SYMLINK+="modem"
+        """),
+
+    Rules.new(
+        "program result substitution",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda5",
+            exp_links       = ["special-device-5"],
+            not_exp_links   = ["not"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", PROGRAM=="/bin/echo -n special-device", RESULT=="-special-*", SYMLINK+="not"
+        SUBSYSTEMS=="scsi", PROGRAM=="/bin/echo -n special-device", RESULT=="special-*", SYMLINK+="%c-%n"
+        """),
+
+    Rules.new(
+        "program result substitution (newline removal)",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda5",
+            exp_links       = ["newline_removed"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", PROGRAM=="/bin/echo test", RESULT=="test", SYMLINK+="newline_removed"
+        """),
+
+    Rules.new(
+        "program result substitution",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda5",
+            exp_links       = ["test-0:0:0:0"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", PROGRAM=="/bin/echo -n test-%b", RESULT=="test-0:0*", SYMLINK+="%c"
+        """),
+
+    Rules.new(
+        "program with lots of arguments",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda5",
+            exp_links       = ["foo9"],
+            not_exp_links   = ["foo3", "foo4", "foo5", "foo6", "foo7", "foo8"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", PROGRAM=="/bin/echo -n foo3 foo4 foo5 foo6 foo7 foo8 foo9", KERNEL=="sda5", SYMLINK+="%c{7}"
+        """),
+
+    Rules.new(
+        "program with subshell",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda5",
+            exp_links       = ["bar9"],
+            not_exp_links   = ["foo3", "foo4", "foo5", "foo6", "foo7", "foo8"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", PROGRAM=="/bin/sh -c 'echo foo3 foo4 foo5 foo6 foo7 foo8 foo9 | sed  s/foo9/bar9/'", KERNEL=="sda5", SYMLINK+="%c{7}"
+        """),
+
+    Rules.new(
+        "program arguments combined with apostrophes",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda5",
+            exp_links       = ["foo7"],
+            not_exp_links   = ["foo3", "foo4", "foo5", "foo6", "foo8"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", PROGRAM=="/bin/echo -n 'foo3 foo4'   'foo5   foo6   foo7 foo8'", KERNEL=="sda5", SYMLINK+="%c{5}"
+        """),
+
+    Rules.new(
+        "program arguments combined with escaped double quotes, part 1",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda5",
+            exp_links       = ["foo2"],
+            not_exp_links   = ["foo1"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", PROGRAM=="/bin/sh -c 'printf %%s \"foo1 foo2\" | grep \"foo1 foo2\"'", KERNEL=="sda5", SYMLINK+="%c{2}"
+        """),
+
+    Rules.new(
+        "program arguments combined with escaped double quotes, part 2",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda5",
+            exp_links       = ["foo2"],
+            not_exp_links   = ["foo1"],
+        ),
+        rules = r"""
+SUBSYSTEMS=="scsi", PROGRAM=="/bin/sh -c \"printf %%s 'foo1 foo2' | grep 'foo1 foo2'\"", KERNEL=="sda5", SYMLINK+="%c{2}"
+        """),
+
+    Rules.new(
+        "program arguments combined with escaped double quotes, part 3",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda5",
+            exp_links       = ["foo2"],
+            not_exp_links   = ["foo1", "foo3"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", PROGRAM=="/bin/sh -c 'printf \"%%s %%s\" \"foo1 foo2\" \"foo3\"| grep \"foo1 foo2\"'", KERNEL=="sda5", SYMLINK+="%c{2}"
+        """),
+
+    Rules.new(
+        "characters before the %c{N} substitution",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda5",
+            exp_links       = ["my-foo9"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", PROGRAM=="/bin/echo -n foo3 foo4 foo5 foo6 foo7 foo8 foo9", KERNEL=="sda5", SYMLINK+="my-%c{7}"
+        """),
+
+    Rules.new(
+        "substitute the second to last argument",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda5",
+            exp_links       = ["my-foo8"],
+            not_exp_links   = ["my-foo3", "my-foo4", "my-foo5", "my-foo6", "my-foo7", "my-foo9"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", PROGRAM=="/bin/echo -n foo3 foo4 foo5 foo6 foo7 foo8 foo9", KERNEL=="sda5", SYMLINK+="my-%c{6}"
+        """),
+
+    Rules.new(
+        "test substitution by variable name",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda5",
+            exp_links       = ["Major:8-minor:5-kernelnumber:5-id:0:0:0:0"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNELS=="0:0:0:0", SYMLINK+="Major:$major-minor:$minor-kernelnumber:$number-id:$id"
+        """),
+
+    Rules.new(
+        "test substitution by variable name 2",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda5",
+            exp_links       = ["Major:8-minor:5-kernelnumber:5-id:0:0:0:0"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNELS=="0:0:0:0", DEVPATH=="*/sda/*", SYMLINK+="Major:$major-minor:%m-kernelnumber:$number-id:$id"
+        """),
+
+    Rules.new(
+        "test substitution by variable name 3",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda5",
+            exp_links       = ["850:0:0:05"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNELS=="0:0:0:0", DEVPATH=="*/sda/*", SYMLINK+="%M%m%b%n"
+        """),
+
+    Rules.new(
+        "test substitution by variable name 4",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda5",
+            exp_links       = ["855"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNELS=="0:0:0:0", DEVPATH=="*/sda/*", SYMLINK+="$major$minor$number"
+        """),
+
+    Rules.new(
+        "test substitution by variable name 5",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda5",
+            exp_links       = ["8550:0:0:0"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNELS=="0:0:0:0", DEVPATH=="*/sda/*", SYMLINK+="$major%m%n$id"
+        """),
+
+    Rules.new(
+        "non matching SUBSYSTEMS for device with no parent",
+        Device(
+            "/devices/virtual/tty/console",
+            exp_links       = ["TTY"],
+            not_exp_links   = ["foo"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", PROGRAM=="/bin/echo -n foo", RESULT=="foo", SYMLINK+="foo"
+        KERNEL=="console", SYMLINK+="TTY"
+        """),
+
+    Rules.new(
+        "non matching SUBSYSTEMS",
+        Device(
+            "/devices/virtual/tty/console",
+            exp_links       = ["TTY"],
+            not_exp_links   = ["foo"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="foo", ATTRS{dev}=="5:1", SYMLINK+="foo"
+        KERNEL=="console", SYMLINK+="TTY"
+        """),
+
+    Rules.new(
+        "ATTRS match",
+        Device(
+            "/devices/virtual/tty/console",
+            exp_links       = ["foo", "TTY"],
+        ),
+        rules = r"""
+        KERNEL=="console", SYMLINK+="TTY"
+        ATTRS{dev}=="5:1", SYMLINK+="foo"
+        """),
+
+    Rules.new(
+        "ATTR (empty file)",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["empty", "not-something"],
+            not_exp_links   = ["something", "not-empty"],
+        ),
+        rules = r"""
+        KERNEL=="sda", ATTR{test_empty_file}=="?*", SYMLINK+="something"
+        KERNEL=="sda", ATTR{test_empty_file}!="", SYMLINK+="not-empty"
+        KERNEL=="sda", ATTR{test_empty_file}=="", SYMLINK+="empty"
+        KERNEL=="sda", ATTR{test_empty_file}!="?*", SYMLINK+="not-something"
+        """),
+
+    Rules.new(
+        "ATTR (non-existent file)",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["non-existent", "wrong"],
+            not_exp_links   = ["something", "empty", "not-empty",
+                               "not-something", "something"],
+        ),
+        rules = r"""
+        KERNEL=="sda", ATTR{nofile}=="?*", SYMLINK+="something"
+        KERNEL=="sda", ATTR{nofile}!="", SYMLINK+="not-empty"
+        KERNEL=="sda", ATTR{nofile}=="", SYMLINK+="empty"
+        KERNEL=="sda", ATTR{nofile}!="?*", SYMLINK+="not-something"
+        KERNEL=="sda", TEST!="nofile", SYMLINK+="non-existent"
+        KERNEL=="sda", SYMLINK+="wrong"
+        """),
+
+    Rules.new(
+        "program and bus type match",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["scsi-0:0:0:0"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="usb", PROGRAM=="/bin/echo -n usb-%b", SYMLINK+="%c"
+        SUBSYSTEMS=="scsi", PROGRAM=="/bin/echo -n scsi-%b", SYMLINK+="%c"
+        SUBSYSTEMS=="foo", PROGRAM=="/bin/echo -n foo-%b", SYMLINK+="%c"
+        """),
+
+    Rules.new(
+        "sysfs parent hierarchy",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["modem"],
+        ),
+        rules = r"""
+        ATTRS{idProduct}=="007b", SYMLINK+="modem"
+        """),
+
+    Rules.new(
+        "name test with ! in the name",
+        Device(
+            "/devices/virtual/block/fake!blockdev0",
+            devnode         = "fake/blockdev0",
+            exp_links       = ["is/a/fake/blockdev0"],
+            not_exp_links   = ["is/not/a/fake/blockdev0", "modem"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", SYMLINK+="is/not/a/%k"
+        SUBSYSTEM=="block", SYMLINK+="is/a/%k"
+        KERNEL=="ttyACM0", SYMLINK+="modem"
+        """),
+
+    Rules.new(
+        "name test with ! in the name, but no matching rule",
+        Device(
+            "/devices/virtual/block/fake!blockdev0",
+            devnode         = "fake/blockdev0",
+            not_exp_links   = ["modem"],
+        ),
+        rules = r"""
+        KERNEL=="ttyACM0", SYMLINK+="modem"
+        """),
+
+    Rules.new(
+        "KERNELS rule",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["scsi-0:0:0:0"],
+            not_exp_links   = ["no-match", "short-id", "not-scsi"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="usb", KERNELS=="0:0:0:0", SYMLINK+="not-scsi"
+        SUBSYSTEMS=="scsi", KERNELS=="0:0:0:1", SYMLINK+="no-match"
+        SUBSYSTEMS=="scsi", KERNELS==":0", SYMLINK+="short-id"
+        SUBSYSTEMS=="scsi", KERNELS=="/0:0:0:0", SYMLINK+="no-match"
+        SUBSYSTEMS=="scsi", KERNELS=="0:0:0:0", SYMLINK+="scsi-0:0:0:0"
+        """),
+
+    Rules.new(
+        "KERNELS wildcard all",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["scsi-0:0:0:0"],
+            not_exp_links   = ["no-match", "before"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNELS=="*:1", SYMLINK+="no-match"
+        SUBSYSTEMS=="scsi", KERNELS=="*:0:1", SYMLINK+="no-match"
+        SUBSYSTEMS=="scsi", KERNELS=="*:0:0:1", SYMLINK+="no-match"
+        SUBSYSTEMS=="scsi", KERNEL=="0:0:0:0", SYMLINK+="before"
+        SUBSYSTEMS=="scsi", KERNELS=="*", SYMLINK+="scsi-0:0:0:0"
+        """),
+
+    Rules.new(
+        "KERNELS wildcard partial",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["scsi-0:0:0:0", "before"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNELS=="0:0:0:0", SYMLINK+="before"
+        SUBSYSTEMS=="scsi", KERNELS=="*:0", SYMLINK+="scsi-0:0:0:0"
+        """),
+
+    Rules.new(
+        "KERNELS wildcard partial 2",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["scsi-0:0:0:0", "before"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNELS=="0:0:0:0", SYMLINK+="before"
+        SUBSYSTEMS=="scsi", KERNELS=="*:0:0:0", SYMLINK+="scsi-0:0:0:0"
+        """),
+
+    Rules.new(
+        "substitute attr with link target value (first match)",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["driver-is-sd"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", SYMLINK+="driver-is-$attr{driver}"
+        """),
+
+    Rules.new(
+        "substitute attr with link target value (currently selected device)",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["driver-is-ahci"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="pci", SYMLINK+="driver-is-$attr{driver}"
+        """),
+
+    Rules.new(
+        "ignore ATTRS attribute whitespace",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["ignored"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", ATTRS{whitespace_test}=="WHITE  SPACE", SYMLINK+="ignored"
+        """),
+
+    Rules.new(
+        "do not ignore ATTRS attribute whitespace",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["matched-with-space"],
+            not_exp_links   = ["wrong-to-ignore"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", ATTRS{whitespace_test}=="WHITE  SPACE ", SYMLINK+="wrong-to-ignore"
+        SUBSYSTEMS=="scsi", ATTRS{whitespace_test}=="WHITE  SPACE   ", SYMLINK+="matched-with-space"
+        """),
+
+    Rules.new(
+        "permissions USER=bad GROUP=name",
+        Device(
+            "/devices/virtual/tty/tty33",
+            exp_perms       = "0:0:0600",
+        ),
+        rules = r"""
+        KERNEL=="tty33", OWNER="bad", GROUP="name"
+        """),
+
+    Rules.new(
+        "permissions OWNER=1",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["node"],
+            exp_perms       = "1::0600",
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNEL=="sda", SYMLINK+="node", OWNER="1"
+        """),
+
+    Rules.new(
+        "permissions GROUP=1",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["node"],
+            exp_perms       = ":1:0660",
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNEL=="sda", SYMLINK+="node", GROUP="1"
+        """),
+
+    Rules.new(
+        "textual user id",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["node"],
+            exp_perms       = "daemon::0600",
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNEL=="sda", SYMLINK+="node", OWNER="daemon"
+        """),
+
+    Rules.new(
+        "textual group id",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["node"],
+            exp_perms       = ":daemon:0660",
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNEL=="sda", SYMLINK+="node", GROUP="daemon"
+        """),
+
+    Rules.new(
+        "textual user/group id",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["node"],
+            exp_perms       = "root:audio:0660",
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNEL=="sda", SYMLINK+="node", OWNER="root", GROUP="audio"
+        """),
+
+    Rules.new(
+        "permissions MODE=0777",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["node"],
+            exp_perms       = "::0777",
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNEL=="sda", SYMLINK+="node", MODE="0777"
+        """),
+
+    Rules.new(
+        "permissions OWNER=1 GROUP=1 MODE=0777",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["node"],
+            exp_perms       = "1:1:0777",
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNEL=="sda", SYMLINK+="node", OWNER="1", GROUP="1", MODE="0777"
+        """),
+
+    Rules.new(
+        "permissions OWNER to 1",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_perms       = "1::",
+        ),
+        rules = r"""
+        KERNEL=="ttyACM[0-9]*", SYMLINK+="ttyACM%n", OWNER="1"
+        """),
+
+    Rules.new(
+        "permissions GROUP to 1",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_perms       = ":1:0660",
+        ),
+        rules = r"""
+        KERNEL=="ttyACM[0-9]*", SYMLINK+="ttyACM%n", GROUP="1"
+        """),
+
+    Rules.new(
+        "permissions MODE to 0060",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_perms       = "::0060",
+        ),
+        rules = r"""
+        KERNEL=="ttyACM[0-9]*", SYMLINK+="ttyACM%n", MODE="0060"
+        """),
+
+    Rules.new(
+        "permissions OWNER, GROUP, MODE",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_perms       = "1:1:0777",
+        ),
+        rules = r"""
+        KERNEL=="ttyACM[0-9]*", SYMLINK+="ttyACM%n", OWNER="1", GROUP="1", MODE="0777"
+        """),
+
+    Rules.new(
+        "permissions only rule",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_perms       = "1:1:0777",
+        ),
+        rules = r"""
+        KERNEL=="ttyACM[0-9]*", OWNER="1", GROUP="1", MODE="0777"
+        KERNEL=="ttyUSX[0-9]*", OWNER="2", GROUP="2", MODE="0444"
+        KERNEL=="ttyACM[0-9]*", SYMLINK+="ttyACM%n"
+        """),
+
+    Rules.new(
+        "multiple permissions only rule",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_perms       = "1:1:0777",
+        ),
+        rules = r"""
+        SUBSYSTEM=="tty", OWNER="1"
+        SUBSYSTEM=="tty", GROUP="1"
+        SUBSYSTEM=="tty", MODE="0777"
+        KERNEL=="ttyUSX[0-9]*", OWNER="2", GROUP="2", MODE="0444"
+        KERNEL=="ttyACM[0-9]*", SYMLINK+="ttyACM%n"
+        """),
+
+    Rules.new(
+        "permissions only rule with override at SYMLINK+ rule",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_perms       = "1:2:0777",
+        ),
+        rules = r"""
+        SUBSYSTEM=="tty", OWNER="1"
+        SUBSYSTEM=="tty", GROUP="1"
+        SUBSYSTEM=="tty", MODE="0777"
+        KERNEL=="ttyUSX[0-9]*", OWNER="2", GROUP="2", MODE="0444"
+        KERNEL=="ttyACM[0-9]*", SYMLINK+="ttyACM%n", GROUP="2"
+        """),
+
+    Rules.new(
+        "major/minor number test",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["node"],
+            exp_major_minor = "8:0",
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNEL=="sda", SYMLINK+="node"
+        """),
+
+    Rules.new(
+        "big major number test",
+        Device(
+            "/devices/virtual/misc/misc-fake1",
+            exp_links       = ["node"],
+            exp_major_minor = "4095:1",
+        ),
+        rules = r"""
+        KERNEL=="misc-fake1", SYMLINK+="node"
+        """),
+
+    Rules.new(
+        "big major and big minor number test",
+        Device(
+            "/devices/virtual/misc/misc-fake89999",
+            exp_links       = ["node"],
+            exp_major_minor = "4095:89999",
+        ),
+        rules = r"""
+        KERNEL=="misc-fake89999", SYMLINK+="node"
+        """),
+
+    Rules.new(
+        "multiple symlinks with format char",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["symlink1-0", "symlink2-ttyACM0", "symlink3-"],
+        ),
+        rules = r"""
+        KERNEL=="ttyACM[0-9]*", SYMLINK="symlink1-%n symlink2-%k symlink3-%b"
+        """),
+
+    Rules.new(
+        "multiple symlinks with a lot of s p a c e s",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["one", "two"],
+            not_exp_links       = [" "],
+        ),
+        rules = r"""
+        KERNEL=="ttyACM[0-9]*", SYMLINK="  one     two        "
+        """),
+
+    Rules.new(
+        "symlink with spaces in substituted variable",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["name-one_two_three-end"],
+            not_exp_links   = [" "],
+        ),
+        rules = r"""
+        ENV{WITH_WS}="one two three"
+        SYMLINK="name-$env{WITH_WS}-end"
+        """),
+
+    Rules.new(
+        "symlink with leading space in substituted variable",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["name-one_two_three-end"],
+            not_exp_links   = [" "],
+        ),
+        rules = r"""
+        ENV{WITH_WS}="   one two three"
+        SYMLINK="name-$env{WITH_WS}-end"
+        """),
+
+    Rules.new(
+        "symlink with trailing space in substituted variable",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["name-one_two_three-end"],
+            not_exp_links   = [" "],
+        ),
+        rules = r"""
+        ENV{WITH_WS}="one two three   "
+        SYMLINK="name-$env{WITH_WS}-end"
+        """),
+
+    Rules.new(
+        "symlink with lots of space in substituted variable",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["name-one_two_three-end"],
+            not_exp_links   = [" "],
+        ),
+        rules = r"""
+        ENV{WITH_WS}="   one two three   "
+        SYMLINK="name-$env{WITH_WS}-end"
+        """),
+
+    Rules.new(
+        "symlink with multiple spaces in substituted variable",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["name-one_two_three-end"],
+            not_exp_links   = [" "],
+        ),
+        rules = r"""
+        ENV{WITH_WS}="   one  two  three   "
+        SYMLINK="name-$env{WITH_WS}-end"
+        """),
+
+    Rules.new(
+        "symlink with space and var with space",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["first", "name-one_two_three-end",
+                               "another_symlink", "a", "b", "c"],
+            not_exp_links   = [" "],
+        ),
+        rules = r"""
+        ENV{WITH_WS}="   one  two  three   "
+        SYMLINK="  first  name-$env{WITH_WS}-end another_symlink a b c "
+        """),
+
+    Rules.new(
+        "symlink with env which contain slash (see #19309)",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["first", "name-aaa_bbb_ccc-end",
+                               "another_symlink", "a", "b", "c"],
+            not_exp_links   = ["ame-aaa/bbb/ccc-end"],
+        ),
+        rules = r"""
+        ENV{WITH_SLASH}="aaa/bbb/ccc"
+        OPTIONS="string_escape=replace", ENV{REPLACED}="$env{WITH_SLASH}"
+        SYMLINK="  first  name-$env{REPLACED}-end another_symlink a b c "
+        """),
+
+    Rules.new(
+        "symlink creation (same directory)",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["modem0"],
+        ),
+        rules = r"""
+        KERNEL=="ttyACM[0-9]*", SYMLINK+="ttyACM%n", SYMLINK="modem%n"
+        """),
+
+    Rules.new(
+        "multiple symlinks",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["first-0", "second-0", "third-0"],
+        ),
+        rules = r"""
+        KERNEL=="ttyACM0", SYMLINK="first-%n second-%n third-%n"
+        """),
+
+    Rules.new(
+        "symlink name '.'",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+        ),
+        # we get a warning, but the process does not fail
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNEL=="sda", SYMLINK+="."
+        """),
+
+    Rules.new(
+        "symlink node to itself",
+        Device(
+            "/devices/virtual/tty/tty0",
+        ),
+        # we get a warning, but the process does not fail
+        rules = r"""
+        KERNEL=="tty0", SYMLINK+="tty0"
+        """),
+
+    Rules.new(
+        "symlink %n substitution",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["symlink0"],
+        ),
+        rules = r"""
+        KERNEL=="ttyACM[0-9]*", SYMLINK+="ttyACM%n", SYMLINK+="symlink%n"
+        """),
+
+    Rules.new(
+        "symlink %k substitution",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["symlink-ttyACM0"],
+        ),
+        rules = r"""
+        KERNEL=="ttyACM[0-9]*", SYMLINK+="ttyACM%n", SYMLINK+="symlink-%k"
+        """),
+
+    Rules.new(
+        "symlink %M:%m substitution",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["major-166:0"],
+        ),
+        rules = r"""
+        KERNEL=="ttyACM[0-9]*", SYMLINK+="ttyACM%n", SYMLINK+="major-%M:%m"
+        """),
+
+    Rules.new(
+        "symlink %b substitution",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["symlink-0:0:0:0"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNEL=="sda", SYMLINK+="symlink-%b"
+        """),
+
+    Rules.new(
+        "symlink %c substitution",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["test"],
+        ),
+        rules = r"""
+        KERNEL=="ttyACM[0-9]*", PROGRAM=="/bin/echo test", SYMLINK+="%c"
+        """),
+
+    Rules.new(
+        "symlink %c{N} substitution",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["test"],
+            not_exp_links   = ["symlink", "this"],
+        ),
+        rules = r"""
+        KERNEL=="ttyACM[0-9]*", PROGRAM=="/bin/echo symlink test this", SYMLINK+="%c{2}"
+        """),
+
+    Rules.new(
+        "symlink %c{N+} substitution",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["test", "this"],
+            not_exp_links   = ["symlink"],
+        ),
+        rules = r"""
+        KERNEL=="ttyACM[0-9]*", PROGRAM=="/bin/echo symlink test this", SYMLINK+="%c{2+}"
+        """),
+
+    Rules.new(
+        "symlink only rule with %c{N+}",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["test", "this"],
+            not_exp_links   = ["symlink"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNEL=="sda", PROGRAM=="/bin/echo link test this" SYMLINK+="%c{2+}"
+        """),
+
+    Rules.new(
+        "symlink %s{filename} substitution",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["166:0"],
+        ),
+        rules = r"""
+        KERNEL=="ttyACM[0-9]*", SYMLINK+="%s{dev}"
+        """),
+
+    Rules.new(
+        "program result substitution (numbered part of)",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda5",
+            exp_links       = ["link1", "link2"],
+            not_exp_links   = ["node"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", PROGRAM=="/bin/echo -n node link1 link2", RESULT=="node *", SYMLINK+="%c{2} %c{3}"
+        """),
+
+    Rules.new(
+        "program result substitution (numbered part of+)",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda5",
+            exp_links       = ["link1", "link2", "link3", "link4"],
+            not_exp_links   = ["node"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", PROGRAM=="/bin/echo -n node link1 link2 link3 link4", RESULT=="node *", SYMLINK+="%c{2+}"
+        """),
+
+    Rules.new(
+        "SUBSYSTEM match test",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["node"],
+            not_exp_links   = ["should_not_match", "should_not_match2"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNEL=="sda", SYMLINK+="should_not_match", SUBSYSTEM=="vc"
+        SUBSYSTEMS=="scsi", KERNEL=="sda", SYMLINK+="node", SUBSYSTEM=="block"
+        SUBSYSTEMS=="scsi", KERNEL=="sda", SYMLINK+="should_not_match2", SUBSYSTEM=="vc"
+        """),
+
+    Rules.new(
+        "DRIVERS match test",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["node"],
+            not_exp_links   = ["should_not_match"]
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNEL=="sda", SYMLINK+="should_not_match", DRIVERS=="sd-wrong"
+        SUBSYSTEMS=="scsi", KERNEL=="sda", SYMLINK+="node", DRIVERS=="sd"
+        """),
+
+    Rules.new(
+        "devnode substitution test",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["node"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNEL=="sda", PROGRAM=="/usr/bin/test -b %N" SYMLINK+="node"
+        """),
+
+    Rules.new(
+        "parent node name substitution test",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1",
+            exp_links       = ["sda-part-1"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNEL=="sda1", SYMLINK+="%P-part-%n"
+        """),
+
+    Rules.new(
+        "udev_root substitution",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1",
+            exp_links       = ["start-/dev-end"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNEL=="sda1", SYMLINK+="start-%r-end"
+        """),
+
+    Rules.new(
+        # This is not supported any more
+        "last_rule option",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1",
+            exp_links       = ["last", "very-last"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNEL=="sda1", SYMLINK+="last", OPTIONS="last_rule"
+        SUBSYSTEMS=="scsi", KERNEL=="sda1", SYMLINK+="very-last"
+        """),
+
+    Rules.new(
+        "negation KERNEL!=",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1",
+            exp_links       = ["match", "before"],
+            not_exp_links   = ["matches-but-is-negated"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNEL!="sda1", SYMLINK+="matches-but-is-negated"
+        SUBSYSTEMS=="scsi", KERNEL=="sda1", SYMLINK+="before"
+        SUBSYSTEMS=="scsi", KERNEL!="xsda1", SYMLINK+="match"
+        """),
+
+    Rules.new(
+        "negation SUBSYSTEM!=",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1",
+            exp_links       = ["before", "not-anything"],
+            not_exp_links   = ["matches-but-is-negated"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", SUBSYSTEM=="block", KERNEL!="sda1", SYMLINK+="matches-but-is-negated"
+        SUBSYSTEMS=="scsi", KERNEL=="sda1", SYMLINK+="before"
+        SUBSYSTEMS=="scsi", SUBSYSTEM!="anything", SYMLINK+="not-anything"
+        """),
+
+    Rules.new(
+        "negation PROGRAM!= exit code",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1",
+            exp_links       = ["before", "nonzero-program"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNEL=="sda1", SYMLINK+="before"
+        KERNEL=="sda1", PROGRAM!="/bin/false", SYMLINK+="nonzero-program"
+        """),
+
+    Rules.new(
+        "ENV{} test",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1",
+            exp_links       = ["true"],
+            not_exp_links   = ["bad", "wrong"],
+        ),
+        rules = r"""
+        ENV{ENV_KEY_TEST}="test"
+        SUBSYSTEMS=="scsi", KERNEL=="sda1", ENV{ENV_KEY_TEST}=="go", SYMLINK+="wrong"
+        SUBSYSTEMS=="scsi", KERNEL=="sda1", ENV{ENV_KEY_TEST}=="test", SYMLINK+="true"
+        SUBSYSTEMS=="scsi", KERNEL=="sda1", ENV{ENV_KEY_TEST}=="bad", SYMLINK+="bad"
+        """),
+
+    Rules.new(
+        "ENV{} test",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1",
+            exp_links       = ["true"],
+            not_exp_links   = ["bad", "wrong", "no"],
+        ),
+        rules = r"""
+        ENV{ENV_KEY_TEST}="test"
+        SUBSYSTEMS=="scsi", KERNEL=="sda1", ENV{ENV_KEY_TEST}=="go", SYMLINK+="wrong"
+        SUBSYSTEMS=="scsi", KERNEL=="sda1", ENV{ENV_KEY_TEST}=="yes", ENV{ACTION}=="add", ENV{DEVPATH}=="*/block/sda/sdax1", SYMLINK+="no"
+        SUBSYSTEMS=="scsi", KERNEL=="sda1", ENV{ENV_KEY_TEST}=="test", ENV{ACTION}=="add", ENV{DEVPATH}=="*/block/sda/sda1", SYMLINK+="true"
+        SUBSYSTEMS=="scsi", KERNEL=="sda1", ENV{ENV_KEY_TEST}=="bad", SYMLINK+="bad"
+        """),
+
+    Rules.new(
+        "ENV{} test (assign)",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1",
+            exp_links       = ["true", "before"],
+            not_exp_links   = ["no"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNEL=="sda1", ENV{ASSIGN}="true"
+        SUBSYSTEMS=="scsi", KERNEL=="sda1", ENV{ASSIGN}=="yes", SYMLINK+="no"
+        SUBSYSTEMS=="scsi", KERNEL=="sda1", SYMLINK+="before"
+        SUBSYSTEMS=="scsi", KERNEL=="sda1", ENV{ASSIGN}=="true", SYMLINK+="true"
+        """),
+
+    Rules.new(
+        "ENV{} test (assign 2 times)",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1",
+            exp_links       = ["true", "before"],
+            not_exp_links   = ["no", "bad"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNEL=="sda1", ENV{ASSIGN}="true"
+        SUBSYSTEMS=="scsi", KERNEL=="sda1", ENV{ASSIGN}="absolutely-$env{ASSIGN}"
+        SUBSYSTEMS=="scsi", KERNEL=="sda1", SYMLINK+="before"
+        SUBSYSTEMS=="scsi", KERNEL=="sda1", ENV{ASSIGN}=="yes", SYMLINK+="no"
+        SUBSYSTEMS=="scsi", KERNEL=="sda1", ENV{ASSIGN}=="true", SYMLINK+="bad"
+        SUBSYSTEMS=="scsi", KERNEL=="sda1", ENV{ASSIGN}=="absolutely-true", SYMLINK+="true"
+        """),
+
+    Rules.new(
+        "ENV{} test (assign2)",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1",
+            exp_links       = ["part"],
+            not_exp_links   = ["disk"],
+        ),
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["disk"],
+            not_exp_links   = ["part"],
+        ),
+        rules = r"""
+        SUBSYSTEM=="block", KERNEL=="*[0-9]", ENV{PARTITION}="true", ENV{MAINDEVICE}="false"
+        SUBSYSTEM=="block", KERNEL=="*[!0-9]", ENV{PARTITION}="false", ENV{MAINDEVICE}="true"
+        ENV{MAINDEVICE}=="true", SYMLINK+="disk"
+        SUBSYSTEM=="block", SYMLINK+="before"
+        ENV{PARTITION}=="true", SYMLINK+="part"
+        """),
+
+    Rules.new(
+        "untrusted string sanitize",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1",
+            exp_links       = ["sane"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNEL=="sda1", PROGRAM=="/bin/echo -e name; (/usr/bin/badprogram)", RESULT=="name_ _/usr/bin/badprogram_", SYMLINK+="sane"
+        """),
+
+    Rules.new(
+        "untrusted string sanitize (don't replace utf8)",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1",
+            exp_links       = ["uber"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNEL=="sda1", PROGRAM=="/bin/echo -e \xc3\xbcber" RESULT=="über", SYMLINK+="uber"
+        """),
+
+    Rules.new(
+        "untrusted string sanitize (replace invalid utf8)",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1",
+            exp_links       = ["replaced"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", KERNEL=="sda1", PROGRAM=="/bin/echo -e \xef\xe8garbage", RESULT=="__garbage", SYMLINK+="replaced"
+        """),
+
+    Rules.new(
+        "read sysfs value from parent device",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["serial-354172020305000"],
+        ),
+        rules = r"""
+        KERNEL=="ttyACM*", ATTRS{serial}=="?*", SYMLINK+="serial-%s{serial}"
+        """),
+
+    Rules.new(
+        "match against empty key string",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["ok"],
+            not_exp_links   = ["not-1-ok", "not-2-ok", "not-3-ok"],
+        ),
+        rules = r"""
+        KERNEL=="sda", ATTRS{nothing}!="", SYMLINK+="not-1-ok"
+        KERNEL=="sda", ATTRS{nothing}=="", SYMLINK+="not-2-ok"
+        KERNEL=="sda", ATTRS{vendor}!="", SYMLINK+="ok"
+        KERNEL=="sda", ATTRS{vendor}=="", SYMLINK+="not-3-ok"
+        """),
+
+    Rules.new(
+        "check ACTION value",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["ok"],
+            not_exp_links   = ["unknown-not-ok"],
+        ),
+        rules = r"""
+        ACTION=="unknown", KERNEL=="sda", SYMLINK+="unknown-not-ok"
+        ACTION=="add", KERNEL=="sda", SYMLINK+="ok"
+        """),
+
+    Rules.new(
+        "final assignment",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["ok"],
+            exp_perms       = "root:tty:0640",
+        ),
+        rules = r"""
+        KERNEL=="sda", GROUP:="tty"
+        KERNEL=="sda", GROUP="root", MODE="0640", SYMLINK+="ok"
+        """),
+
+    Rules.new(
+        "final assignment 2",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["ok"],
+            exp_perms       = "root:tty:0640",
+        ),
+        rules = r"""
+        KERNEL=="sda", GROUP:="tty"
+        SUBSYSTEM=="block", MODE:="640"
+        KERNEL=="sda", GROUP="root", MODE="0666", SYMLINK+="ok"
+        """),
+
+    Rules.new(
+        "env substitution",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["node-add-me"],
+        ),
+        rules = r"""
+        KERNEL=="sda", MODE="0666", SYMLINK+="node-$env{ACTION}-me"
+        """),
+
+    Rules.new(
+        "reset list to current value",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["three"],
+            not_exp_links   = ["two", "one"],
+        ),
+        rules = r"""
+        KERNEL=="ttyACM[0-9]*", SYMLINK+="one"
+        KERNEL=="ttyACM[0-9]*", SYMLINK+="two"
+        KERNEL=="ttyACM[0-9]*", SYMLINK="three"
+        """),
+
+    Rules.new(
+        "test empty SYMLINK+ (empty override)",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["right"],
+            not_exp_links   = ["wrong"],
+        ),
+        rules = r"""
+        KERNEL=="ttyACM[0-9]*", SYMLINK+="wrong"
+        KERNEL=="ttyACM[0-9]*", SYMLINK=""
+        KERNEL=="ttyACM[0-9]*", SYMLINK+="right"
+        """),
+
+    Rules.new(
+        "test multi matches",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["right", "before"],
+        ),
+        rules = r"""
+        KERNEL=="ttyACM*", SYMLINK+="before"
+        KERNEL=="ttyACM*|nothing", SYMLINK+="right"
+        """),
+
+    Rules.new(
+        "test multi matches 2",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["right", "before"],
+            not_exp_links   = ["nomatch"],
+        ),
+        rules = r"""
+        KERNEL=="dontknow*|*nothing", SYMLINK+="nomatch"
+        KERNEL=="ttyACM*", SYMLINK+="before"
+        KERNEL=="dontknow*|ttyACM*|nothing*", SYMLINK+="right"
+        """),
+
+    Rules.new(
+        "test multi matches 3",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["right"],
+            not_exp_links   = ["nomatch", "wrong1", "wrong2"],
+        ),
+        rules = r"""
+        KERNEL=="dontknow|nothing", SYMLINK+="nomatch"
+        KERNEL=="dontknow|ttyACM0a|nothing|attyACM0", SYMLINK+="wrong1"
+        KERNEL=="X|attyACM0|dontknow|ttyACM0a|nothing|attyACM0", SYMLINK+="wrong2"
+        KERNEL=="dontknow|ttyACM0|nothing", SYMLINK+="right"
+        """),
+
+    Rules.new(
+        "test multi matches 4",
+        Device(
+            "/devices/pci0000:00/0000:00:1d.7/usb5/5-2/5-2:1.0/tty/ttyACM0",
+            exp_links       = ["right"],
+            not_exp_links   = ["nomatch", "wrong1", "wrong2", "wrong3"],
+        ),
+        rules = r"""
+        KERNEL=="dontknow|nothing", SYMLINK+="nomatch"
+        KERNEL=="dontknow|ttyACM0a|nothing|attyACM0", SYMLINK+="wrong1"
+        KERNEL=="X|attyACM0|dontknow|ttyACM0a|nothing|attyACM0", SYMLINK+="wrong2"
+        KERNEL=="all|dontknow|ttyACM0", SYMLINK+="right"
+        KERNEL=="ttyACM0a|nothing", SYMLINK+="wrong3"
+        """),
+
+    Rules.new(
+        "test multi matches 5",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["found"],
+            not_exp_links   = ["bad"],
+        ),
+        rules = r"""
+        KERNEL=="sda", TAG="foo"
+        TAGS=="|foo", SYMLINK+="found"
+        TAGS=="|aaa", SYMLINK+="bad"
+        """),
+
+    Rules.new(
+        "test multi matches 6",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["found"],
+            not_exp_links   = ["bad"],
+        ),
+        rules = r"""
+        KERNEL=="sda", ENV{HOGE}=""
+        ENV{HOGE}=="|foo", SYMLINK+="found"
+        ENV{HOGE}=="aaa|bbb", SYMLINK+="bad"
+        """),
+
+    Rules.new(
+        "test multi matches 7",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["found"],
+            not_exp_links   = ["bad"],
+        ),
+        rules = r"""
+        KERNEL=="sda", TAG="foo"
+        TAGS=="foo||bar", SYMLINK+="found"
+        TAGS=="aaa||bbb", SYMLINK+="bad"
+        """),
+
+    Rules.new(
+        "test multi matches 8",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["found"],
+            not_exp_links   = ["bad"],
+        ),
+        rules = r"""
+        KERNEL=="sda", ENV{HOGE}=""
+        ENV{HOGE}=="foo||bar", SYMLINK+="found"
+        ENV{HOGE}=="aaa|bbb", SYMLINK+="bad"
+        """),
+
+    Rules.new(
+        "test multi matches 9",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["found", "found2"],
+            not_exp_links   = ["bad"],
+        ),
+        rules = r"""
+        KERNEL=="sda", TAG="foo"
+        TAGS=="foo|", SYMLINK+="found"
+        TAGS=="aaa|", SYMLINK+="bad"
+        KERNEL=="sda", TAGS!="hoge", SYMLINK+="found2"
+        KERNEL=="sda", TAGS!="foo", SYMLINK+="bad2"
+        """),
+
+    Rules.new(
+        "test multi matches 10",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["found"],
+            not_exp_links   = ["bad"],
+        ),
+        rules = r"""
+        KERNEL=="sda", ENV{HOGE}=""
+        ENV{HOGE}=="foo|", SYMLINK+="found"
+        ENV{HOGE}=="aaa|bbb", SYMLINK+="bad"
+        """),
+
+    Rules.new(
+        "test multi matches 11",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["found"],
+            not_exp_links   = ["bad"],
+        ),
+        rules = r"""
+        KERNEL=="sda", TAG="c"
+        TAGS=="foo||bar||c", SYMLINK+="found"
+        TAGS=="aaa||bbb||ccc", SYMLINK+="bad"
+        """),
+
+    Rules.new(
+        "TAG refuses invalid string",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["valid", "found"],
+            not_exp_links   = ["empty", "invalid_char", "path", "bad", "bad2"],
+        ),
+        rules = r"""
+       KERNEL=="sda", TAG+="", TAG+="invalid.char", TAG+="path/is/also/invalid", TAG+="valid"
+       TAGS=="", SYMLINK+="empty"
+       TAGS=="invalid.char", SYMLINK+="invalid_char"
+       TAGS=="path/is/also/invalid", SYMLINK+="path"
+       TAGS=="valid", SYMLINK+="valid"
+       TAGS=="valid|", SYMLINK+="found"
+       TAGS=="aaa|", SYMLINK+="bad"
+       TAGS=="aaa|bbb", SYMLINK+="bad2"
+        """),
+
+    Rules.new(
+        "IMPORT parent test",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["parent"],
+        ),
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1",
+            exp_links       = ["parentenv-parent_right"],
+        ),
+        delay = 500000,  # Serialized! We need to sleep here after adding sda
+        rules = r"""
+        KERNEL=="sda1", IMPORT{parent}="PARENT*", SYMLINK+="parentenv-$env{PARENT_KEY}$env{WRONG_PARENT_KEY}"
+        KERNEL=="sda", IMPORT{program}="/bin/echo -e 'PARENT_KEY=parent_right\nWRONG_PARENT_KEY=parent_wrong'"
+        KERNEL=="sda", SYMLINK+="parent"
+        """),
+
+    Rules.new(
+        "GOTO test",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1",
+            exp_links       = ["right"],
+            not_exp_links   = ["wrong", "wrong2"],
+        ),
+        rules = r"""
+        KERNEL=="sda1", GOTO="TEST"
+        KERNEL=="sda1", SYMLINK+="wrong"
+        KERNEL=="sda1", GOTO="BAD"
+        KERNEL=="sda1", SYMLINK+="", LABEL="NO"
+        KERNEL=="sda1", SYMLINK+="right", LABEL="TEST", GOTO="end"
+        KERNEL=="sda1", SYMLINK+="wrong2", LABEL="BAD"
+        LABEL="end"
+        """),
+
+    Rules.new(
+        "GOTO label does not exist",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1",
+            exp_links       = ["right"],
+        ),
+        rules = r"""
+        KERNEL=="sda1", GOTO="does-not-exist"
+        KERNEL=="sda1", SYMLINK+="right",
+        LABEL="exists"
+        """),
+
+    Rules.new(
+        "SYMLINK+ compare test",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1",
+            exp_links       = ["right", "link"],
+            not_exp_links   = ["wrong"],
+        ),
+        rules = r"""
+        KERNEL=="sda1", SYMLINK+="link"
+        KERNEL=="sda1", SYMLINK=="link*", SYMLINK+="right"
+        KERNEL=="sda1", SYMLINK=="nolink*", SYMLINK+="wrong"
+        """),
+
+    Rules.new(
+        "invalid key operation",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1",
+            exp_links       = ["yes"],
+            not_exp_links   = ["no"],
+        ),
+        rules = r"""
+        KERNEL="sda1", SYMLINK+="no"
+        KERNEL=="sda1", SYMLINK+="yes"
+        """),
+
+    Rules.new(
+        "operator chars in attribute",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["yes"],
+        ),
+        rules = r"""
+        KERNEL=="sda", ATTR{test:colon+plus}=="?*", SYMLINK+="yes"
+        """),
+
+    Rules.new(
+        "overlong comment line",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1",
+            exp_links       = ["yes"],
+            not_exp_links   = ["no"],
+        ),
+        rules = r"""
+        # 012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789
+           # 012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789
+        KERNEL=="sda1", SYMLINK+=="no"
+        KERNEL=="sda1", SYMLINK+="yes"
+        """),
+
+    Rules.new(
+        "magic subsys/kernel lookup",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["00:16:41:e2:8d:ff"],
+        ),
+        rules = r"""
+        KERNEL=="sda", SYMLINK+="$attr{[net/eth0]address}"
+        """),
+
+    Rules.new(
+        "TEST absolute path",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["there"],
+            not_exp_links   = ["notthere"],
+        ),
+        rules = r"""
+        TEST=="/etc/passwd", SYMLINK+="there"
+        TEST!="/etc/passwd", SYMLINK+="notthere"
+        """),
+
+    Rules.new(
+        "TEST subsys/kernel lookup",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["yes"],
+        ),
+        rules = r"""
+        KERNEL=="sda", TEST=="[net/eth0]", SYMLINK+="yes"
+        """),
+
+    Rules.new(
+        "TEST relative path",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["relative"],
+        ),
+        rules = r"""
+        KERNEL=="sda", TEST=="size", SYMLINK+="relative"
+        """),
+
+    Rules.new(
+        "TEST wildcard substitution (find queue/nr_requests)",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["found-subdir"],
+        ),
+        rules = r"""
+        KERNEL=="sda", TEST=="*/nr_requests", SYMLINK+="found-subdir"
+        """),
+
+    Rules.new(
+        "TEST MODE=0000",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_perms        = "0:0:0000",
+        ),
+        rules = r"""
+        KERNEL=="sda", MODE="0000"
+        """),
+
+    Rules.new(
+        "TEST PROGRAM feeds OWNER, GROUP, MODE",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_perms       = "1:1:0400",
+        ),
+        rules = r"""
+        KERNEL=="sda", MODE="666"
+        KERNEL=="sda", PROGRAM=="/bin/echo 1 1 0400", OWNER="%c{1}", GROUP="%c{2}", MODE="%c{3}"
+        """),
+
+    Rules.new(
+        "TEST PROGRAM feeds MODE with overflow",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_perms        = "0:0:0440",
+        ),
+        rules = r"""
+        KERNEL=="sda", MODE="440"
+        KERNEL=="sda", PROGRAM=="/bin/echo 0 0 0400letsdoabuffferoverflow0123456789012345789012345678901234567890", OWNER="%c{1}", GROUP="%c{2}", MODE="%c{3}"
+        """),
+
+    Rules.new(
+        "magic [subsys/sysname] attribute substitution",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["sda-8741C4G-end"],
+            exp_perms       = "0:0:0600",
+        ),
+        rules = r"""
+        KERNEL=="sda", SYMLINK+="%k-%s{[dmi/id]product_name}-end"
+        """),
+
+    Rules.new(
+        "builtin path_id",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["disk/by-path/pci-0000:00:1f.2-scsi-0:0:0:0"],
+        ),
+        rules = r"""
+        KERNEL=="sda", IMPORT{builtin}="path_id"
+        KERNEL=="sda", ENV{ID_PATH}=="?*", SYMLINK+="disk/by-path/$env{ID_PATH}"
+        """),
+
+    Rules.new(
+        "add and match tag",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["found"],
+            not_exp_links   = ["bad"],
+        ),
+        rules = r"""
+        SUBSYSTEMS=="scsi", ATTRS{vendor}=="ATA", TAG+="green"
+        TAGS=="green", SYMLINK+="found"
+        TAGS=="blue", SYMLINK+="bad"
+        """),
+
+    Rules.new(
+        "don't crash with lots of tags",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["found"],
+        ),
+        rules = f"""
+        {rules_10k_tags}
+        TAGS=="test1", TAGS=="test500", TAGS=="test1234", TAGS=="test9999", TAGS=="test10000", SYMLINK+="found"
+        """),
+
+    Rules.new(
+        "continuations",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["found"],
+            not_exp_links   = ["bad"],
+        ),
+        rules = f"""
+        {rules_10k_tags_continuation}
+        TAGS=="test1", TAGS=="test500", TAGS=="test1234", TAGS=="test9999", TAGS=="test10000", SYMLINK+="bad"
+        KERNEL=="sda",\\
+        # comment in continuation
+        TAG+="hoge1",\\
+          # space before comment
+        TAG+="hoge2",\\
+        # spaces before and after token are dropped
+          TAG+="hoge3",   \\
+        \\
+         \\
+        TAG+="hoge4"
+        TAGS=="hoge1", TAGS=="hoge2", TAGS=="hoge3", TAGS=="hoge4", SYMLINK+="found"
+        """),
+
+    Rules.new(
+        "continuations with empty line",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["found"],
+            not_exp_links   = ["bad"],
+        ),
+        rules = r"""
+        # empty line finishes continuation
+        KERNEL=="sda", TAG+="foo" \
+
+        KERNEL=="sdb", TAG+="hoge"
+        KERNEL=="sda", TAG+="aaa" \
+        KERNEL=="sdb", TAG+="bbb"
+        TAGS=="foo", SYMLINK+="found"
+        TAGS=="aaa", SYMLINK+="bad"
+        """),
+
+    Rules.new(
+        "continuations with space only line",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda",
+            exp_links       = ["found"],
+            not_exp_links   = ["bad"],
+        ),
+        rules = """
+        # space only line finishes continuation
+        KERNEL=="sda", TAG+="foo" \\
+           \t
+        KERNEL=="sdb", TAG+="hoge"
+        KERNEL=="sda", TAG+="aaa" \\
+        KERNEL=="sdb", TAG+="bbb"
+        TAGS=="foo", SYMLINK+="found"
+        TAGS=="aaa", SYMLINK+="bad"
+        """),
+
+    Rules.new(
+        "multiple devices",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1",
+            exp_links       = ["part-1"],
+        ),
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda5",
+            exp_links       = ["part-5"],
+        ),
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda6",
+            exp_links       = ["part-6"],
+        ),
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda7",
+            exp_links       = ["part-7"],
+        ),
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda8",
+            exp_links       = ["part-8"],
+        ),
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda9",
+            exp_links       = ["part-9"],
+        ),
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda10",
+            exp_links       = ["part-10"],
+        ),
+        rules = r"""
+        SUBSYSTEM=="block", SUBSYSTEMS=="scsi", KERNEL=="sda?*", ENV{DEVTYPE}=="partition", SYMLINK+="part-%n"
+        """),
+
+    Rules.new(
+        "multiple devices, same link name, positive prio",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1",
+            exp_links       = ["part-1"],
+            not_exp_links   = ["partition"],
+        ),
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda5",
+            exp_links       = ["part-5"],
+            not_exp_links   = ["partition"],
+        ),
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda6",
+            not_exp_links   = ["partition"],
+            exp_links       = ["part-6"],
+        ),
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda7",
+            exp_links       = ["part-7", "partition"],
+        ),
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda8",
+            not_exp_links   = ["partition"],
+            exp_links       = ["part-8"],
+        ),
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda9",
+            not_exp_links   = ["partition"],
+            exp_links       = ["part-9"],
+        ),
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda10",
+            not_exp_links   = ["partition"],
+            exp_links       = ["part-10"],
+        ),
+        repeat          = 100,
+        rules = r"""
+        SUBSYSTEM=="block", SUBSYSTEMS=="scsi", KERNEL=="sda?*", ENV{DEVTYPE}=="partition", SYMLINK+="part-%n"
+        SUBSYSTEM=="block", SUBSYSTEMS=="scsi", KERNEL=="sda?*", ENV{DEVTYPE}=="partition", SYMLINK+="partition"
+        KERNEL=="*7", OPTIONS+="link_priority=10"
+        """),
+
+    Rules.new(
+        "multiple devices, same link name, negative prio",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1",
+            exp_links       = ["part-1"],
+            not_exp_links   = ["partition"],
+        ),
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda5",
+            exp_links       = ["part-5"],
+            not_exp_links   = ["partition"],
+        ),
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda6",
+            not_exp_links   = ["partition"],
+            exp_links       = ["part-6"],
+        ),
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda7",
+            exp_links       = ["part-7", "partition"],
+        ),
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda8",
+            not_exp_links   = ["partition"],
+            exp_links       = ["part-8"],
+        ),
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda9",
+            not_exp_links   = ["partition"],
+            exp_links       = ["part-9"],
+        ),
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda10",
+            not_exp_links   = ["partition"],
+            exp_links       = ["part-10"],
+        ),
+        rules = r"""
+        SUBSYSTEM=="block", SUBSYSTEMS=="scsi", KERNEL=="sda?*", ENV{DEVTYPE}=="partition", SYMLINK+="part-%n"
+        SUBSYSTEM=="block", SUBSYSTEMS=="scsi", KERNEL=="sda?*", ENV{DEVTYPE}=="partition", SYMLINK+="partition"
+        KERNEL!="*7", OPTIONS+="link_priority=-10"
+        """),
+
+    Rules.new(
+        "multiple devices, same link name, positive prio, sleep",
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda1",
+            exp_links       = ["part-1"],
+            not_exp_links   = ["partition"],
+        ),
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda5",
+            exp_links       = ["part-5"],
+            not_exp_links   = ["partition"],
+        ),
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda6",
+            not_exp_links   = ["partition"],
+            exp_links       = ["part-6"],
+        ),
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda7",
+            exp_links       = ["part-7", "partition"],
+        ),
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda8",
+            not_exp_links   = ["partition"],
+            exp_links       = ["part-8"],
+        ),
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda9",
+            not_exp_links   = ["partition"],
+            exp_links       = ["part-9"],
+        ),
+        Device(
+            "/devices/pci0000:00/0000:00:1f.2/host0/target0:0:0/0:0:0:0/block/sda/sda10",
+            not_exp_links   = ["partition"],
+            exp_links       = ["part-10"],
+        ),
+        delay = 10000,
+        rules = r"""
+        SUBSYSTEM=="block", SUBSYSTEMS=="scsi", KERNEL=="sda?*", ENV{DEVTYPE}=="partition", SYMLINK+="part-%n"
+        SUBSYSTEM=="block", SUBSYSTEMS=="scsi", KERNEL=="sda?*", ENV{DEVTYPE}=="partition", SYMLINK+="partition"
+        KERNEL=="*7", OPTIONS+="link_priority=10"
+        """),
+
+    Rules.new(
+        'all_block_devs',
+        *all_block_devs(lambda name: (["blockdev"], None) if name.endswith('/sda6') else (None, None)),
+        repeat = 10,
+        rules  = r"""
+        SUBSYSTEM=="block", SUBSYSTEMS=="scsi", KERNEL=="sd*", SYMLINK+="blockdev"
+        KERNEL=="sda6", OPTIONS+="link_priority=10"
+        """),
+]
+
+def fork_and_run_udev(action: str, rules: Rules) -> None:
+    kinder = []
+    for k, device in enumerate(rules.devices):
+        # TODO: valgrind/gdb/strace
+        cmd = [UDEV_BIN, action, device.devpath]
+        if rules.delay:
+            cmd += [f'{k * rules.delay}']
+
+        kinder += [subprocess.Popen(cmd)]
+
+    good = True
+    for c in kinder:
+        if not good:
+            # once something fails, terminate all workers
+            c.terminate()
+        elif c.wait() != 0:
+            good = False
+
+    assert good
+
+
+def environment_issue():
+    if os.getuid() != 0:
+        return 'Must be root to run properly'
+
+    c = subprocess.run(['systemd-detect-virt', '-r', '-q'],
+                       check=False)
+    if c.returncode == 0:
+        return 'Running in a chroot, skipping the test'
+    return None
+
+
+@pytest.fixture(scope='module')
+def udev_setup():
+    issue = environment_issue()
+    if issue:
+        pytest.skip(issue)
+
+    subprocess.run(['umount', UDEV_TMPFS],
+                   stderr=subprocess.DEVNULL,
+                   check=False)
+    UDEV_TMPFS.mkdir(exist_ok=True, parents=True)
+
+    subprocess.check_call(['mount', '-v',
+                                    '-t', 'tmpfs',
+                                    '-o', 'rw,mode=0755,nosuid,noexec',
+                                    'tmpfs', UDEV_TMPFS])
+
+    UDEV_DEV.mkdir(exist_ok=True)
+    # setting group and mode of udev_dev ensures the tests work
+    # even if the parent directory has setgid bit enabled.
+    os.chmod(UDEV_DEV,0o755)
+    os.chown(UDEV_DEV, 0, 0)
+
+    os.mknod(UDEV_DEV / 'null', 0o600 | stat.S_IFCHR, os.makedev(1, 3))
+
+    # check if we are permitted to create block device nodes
+    sda = UDEV_DEV / 'sda'
+    os.mknod(sda, 0o600 | stat.S_IFBLK, os.makedev(8, 0))
+    sda.unlink()
+
+    subprocess.check_call(['cp', '-r', 'test/sys/', UDEV_SYS])
+    subprocess.check_call(['rm', '-rf', UDEV_RUN])
+    UDEV_RUN.mkdir(parents=True)
+
+    if subprocess.run([UDEV_BIN, 'check'],
+                      check=False).returncode != 0:
+        pytest.skip(f'{UDEV_BIN} failed to set up the environment, skipping the test',
+                    allow_module_level=True)
+
+    yield
+
+    subprocess.check_call(['rm', '-rf', UDEV_RUN])
+    subprocess.check_call(['umount', '-v', UDEV_TMPFS])
+    UDEV_TMPFS.rmdir()
+
+
+@pytest.mark.parametrize("rules", RULES, ids=(rule.desc for rule in RULES))
+def test_udev(rules: Rules, udev_setup):
+    assert udev_setup is None
+
+    rules.create_rules_file()
+
+    for _ in range(rules.repeat):
+        fork_and_run_udev('add', rules)
+
+        for device in rules.devices:
+            device.check_add()
+
+        fork_and_run_udev('remove', rules)
+
+        for device in rules.devices:
+            device.check_remove()
+
+if __name__ == '__main__':
+    issue = environment_issue()
+    if issue:
+        print(issue, file=sys.stderr)
+        sys.exit(77)
+    sys.exit(pytest.main(sys.argv))