#!/usr/bin/python3
# encoding=UTF-8

# Copyright © 2012, 2013, 2014 Jakub Wilk <jwilk@debian.org>

# Permission to use, copy, modify, and/or distribute this software for any
# purpose with or without fee is hereby granted, provided that the above
# copyright notice and this permission notice appear in all copies.
#
# THE SOFTWARE IS PROVIDED “AS IS” AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
# REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
# AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
# INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
# LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
# OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
# PERFORMANCE OF THIS SOFTWARE.

'''
simple DEP-8 test runner
'''

import argparse
import errno
import os
import queue as queuemod
import re
import shutil
import stat
import subprocess as ipc
import sys
import tempfile
import threading
import warnings
from debian import deb822


def parse_relations(field):
    '''
    wrap debian.deb822.PkgRelation.parse_relations() to suppress the
    UserWarning about the inability to parse something.
    See https://bugs.debian.org/712513
    '''
    warnings.simplefilter('ignore')
    parsed = deb822.PkgRelation.parse_relations(field)
    warnings.resetwarnings()
    return parsed


def chmod_x(path):
    '''
    chmod a+X <path>
    '''
    old_mode = stat.S_IMODE(os.stat(path).st_mode)
    new_mode = old_mode | ((old_mode & 0o444) >> 2)
    if old_mode != new_mode:
        os.chmod(path, new_mode)
    return old_mode


def annotate_output(child):
    queue = queuemod.Queue()

    def reader(fd, tag):
        buf = b''
        while True:
            assert b'\n' not in buf
            chunk = os.read(fd, 1024)
            if chunk == b'':
                break
            lines = (buf + chunk).split(b'\n')
            buf = lines.pop()
            for line in lines:
                queue.put((tag, line + b'\n'))
        if buf != b'':
            queue.put((tag, buf))
        queue.put(None)
    queue = queuemod.Queue()
    threads = []
    for pipe, tag in [(child.stdout, 'O'), (child.stderr, 'E')]:
        thread = threading.Thread(target=reader, args=(pipe.fileno(), tag))
        thread.start()
        threads += [thread]
    nthreads = len(threads)
    while nthreads > 0:
        item = queue.get()
        if item is None:
            nthreads -= 1
            continue
        yield item
    for thread in threads:
        thread.join()


class Skip(Exception):
    pass


class Flaky(Exception):
    pass


class Fail(Exception):
    pass


class Progress:

    @staticmethod
    def _write(s):
        sys.stdout.write(s)
        sys.stdout.flush()

    def start(self, name):
        pass

    def output(self, line):
        pass

    def skip(self, name, reason):
        raise NotImplementedError

    def fail(self, name, reason):
        raise NotImplementedError

    def ok(self, name):
        raise NotImplementedError

    def close(self):
        pass


class DefaultProgress(Progress):

    _hourglass = r'/-\|'

    def __init__(self):
        self._counter = 0
        self._output = False
        if sys.stdout.isatty():
            self._back = '\b'
        else:
            self._back = ''

    def _reset(self):
        if self._output:
            self._write(self._back)

    def start(self, name):
        self._output = False

    def output(self, line):
        if not self._back:
            return
        hourglass = self._hourglass
        c = self._counter + 1
        self._reset()
        self._write(hourglass[c % len(hourglass)])
        self._counter = c
        self._output = True

    def skip(self, name, reason):
        self._write('S')

    def fail(self, name, reason):
        self._reset()
        self._write('F')

    def ok(self, name):
        self._reset()
        self._write('.')

    def close(self):
        self._write('\n')


class VerboseProgress(Progress):

    def _separator(self):
        self._write('-' * 70 + '\n')

    def start(self, name):
        self._separator()
        self._write('{test}\n'.format(test=name))
        self._separator()

    def output(self, line):
        self._write(line)

    def skip(self, name, reason):
        self._write('{test}: SKIP ({reason})\n'.format(
            test=name, reason=reason))

    def fail(self, name, reason):
        self._separator()
        self._write('{test}: FAIL ({reason})\n'.format(
            test=name, reason=reason))
        self._write('\n')

    def ok(self, name):
        self._separator()
        self._write('{test}: PASS\n'.format(test=name))
        self._write('\n')


class TestCommand:

    def __init__(self, group, command):
        self.group = group
        self.command = command

    def __str__(self):
        return self.command

    @property
    def name(self):
        return str(self)

    def get_command(self):
        return ['sh', '-c', self.command]

    def prepare(self, progress, rw_build_tree):
        pass

    def cleanup(self):
        pass

    def run(self, progress, options):   # pylint: disable=too-many-locals
        command = self.get_command()
        tmpdir1 = tempfile.mkdtemp(prefix='sadt.')
        tmpdir2 = tempfile.mkdtemp(prefix='sadt.')
        environ = dict(os.environ)
        environ['AUTOPKGTEST_TMP'] = tmpdir1
        # only for compatibility with old DEP-8 spec.
        environ['ADTTMP'] = tmpdir2
        child = ipc.Popen(command, stdout=ipc.PIPE,
                          stderr=ipc.PIPE, env=environ)
        output = []
        stderr = False
        for tag, line in annotate_output(child):
            if tag == 'E':
                stderr = True
            this_line = '{tag}: {line}'.format(
                tag=tag,
                line=line.decode(sys.stdout.encoding, 'replace'),
            )
            progress.output(this_line)
            output.append(this_line)
        for fp in child.stdout, child.stderr:
            fp.close()
        rc = child.wait()
        shutil.rmtree(tmpdir1)
        shutil.rmtree(tmpdir2)

        if rc == 77 and options.skippable:
            reason = 'exit status 77 and marked as skippable'
            progress.skip(self, reason)
            raise Skip(self, reason, ''.join(output))

        fail_reason = None

        if rc == 0:
            if stderr and not options.allow_stderr:
                rc = -1
                fail_reason = 'stderr non-empty'
        else:
            fail_reason = 'exit code: {rc}'.format(rc=rc)

        if rc != 0:
            if options.flaky:
                progress.skip(self, fail_reason)
                raise Flaky(self, fail_reason, ''.join(output))

            progress.fail(self, fail_reason)
            raise Fail(self, fail_reason, ''.join(output))

        progress.ok(self)


class Test(TestCommand):

    def __init__(self, group, testname):
        self.testname = testname
        self.original_mode = None
        self.cwd = None
        super(Test, self).__init__(group, testname)

    @property
    def path(self):
        return os.path.join(self.group.tests_directory, self.testname)

    def __str__(self):
        return self.testname

    def get_command(self):
        return [self.path]

    def prepare(self, progress, rw_build_tree):
        if rw_build_tree:
            self.cwd = os.getcwd()
            os.chdir(rw_build_tree)
            chmod_x(self.path)
        else:
            if not os.access(self.path, os.X_OK):
                try:
                    self.original_mode = chmod_x(self.path)
                except OSError as exc:
                    progress.skip(self.testname, '{path} could not be made executable: {exc}'
                                  .format(path=self.path, exc=exc))
                    raise Skip

    def cleanup(self):
        if self.original_mode is not None:
            os.chmod(self.path, self.original_mode)
        if self.cwd is not None:
            os.chdir(self.cwd)


class TestOptions:  # pylint: disable=too-few-public-methods
    def __init__(self):
        self.allow_stderr = False
        self.flaky = False
        self.rw_build_tree_needed = False
        self.skippable = False


class TestGroup:
    def __init__(self):
        self.tests = []
        self.restrictions = frozenset()
        self.features = frozenset()
        self.depends = '@'
        self.tests_directory = 'debian/tests'
        self._depends_checked = False
        self._depends_cache = None

    def __iter__(self):
        return iter(self.tests)

    def expand_depends(self, packages, build_depends):
        if '@' not in self.depends:
            return
        or_clauses = []
        parsed_depends = parse_relations(self.depends)
        for or_clause in parsed_depends:
            if len(or_clause) == 1 and or_clause[0]['name'] == '@builddeps@':
                or_clauses += build_depends
                or_clauses += parse_relations('make')
                continue
            stripped_or_clause = [r for r in or_clause if r['name'] != '@']
            if len(stripped_or_clause) < len(or_clause):
                for package in packages:
                    or_clauses += [
                        stripped_or_clause +
                        [dict(name=package, version=None, arch=None)]
                    ]
            else:
                or_clauses += [or_clause]
        self.depends = deb822.PkgRelation.str(or_clauses)

    def check_depends(self):
        if self._depends_checked:
            if isinstance(self._depends_cache, Exception):
                raise self._depends_cache  # fpos, pylint: disable=raising-bad-type
            return
        child = ipc.Popen(['dpkg-checkbuilddeps', '-d',
                           self.depends], stderr=ipc.PIPE, env={})
        error = child.stderr.read().decode('ASCII')
        child.stderr.close()
        if child.wait() != 0:
            error = re.sub('^dpkg-checkbuilddeps: Unmet build dependencies', 'unmet dependencies',
                           error)
            error = error.rstrip()
            skip = Skip(error)
            self._depends_cache = skip
            raise skip
        else:
            self._depends_checked = True

    def check_restrictions(self, ignored_restrictions):
        options = TestOptions()
        restrictions = self.restrictions - frozenset(ignored_restrictions)

        for r in restrictions:
            if r == 'rw-build-tree':
                options.rw_build_tree_needed = True
            elif r == 'needs-root':
                if os.getuid() != 0:
                    raise Skip('this test needs root privileges')
            elif r == 'breaks-testbed':
                raise Skip(
                    'breaks-testbed restriction is not implemented; use adt-run')
            elif r == 'build-needed':
                raise Skip('source tree not built')
            elif r == 'allow-stderr':
                options.allow_stderr = True
            elif r == 'flaky':
                options.flaky = True
            elif r == 'skippable':
                options.skippable = True
            else:
                raise Skip('unknown restriction: {restr}'.format(restr=r))
        return options

    def check(self, ignored_restrictions=()):
        options = self.check_restrictions(ignored_restrictions)
        self.check_depends()
        return options

    def run(self, test, progress, ignored_restrictions=(), rw_build_tree=None,
            built_source_tree=None):
        ignored_restrictions = set(ignored_restrictions)
        if rw_build_tree:
            ignored_restrictions.add('rw-build-tree')
        if built_source_tree:
            ignored_restrictions.add('build-needed')
        ignored_restrictions.add('needs-recommends')
        ignored_restrictions.add('superficial')
        try:
            options = self.check(ignored_restrictions)
        except Skip as exc:
            progress.skip(test, str(exc))
            raise
        test.prepare(progress, rw_build_tree)
        try:
            progress.start(test)
            test.run(progress, options)
        finally:
            test.cleanup()

    def add_tests(self, tests):
        tests = [Test(self, t) for t in re.split(r'\s*,?\s+', tests)]
        self.tests = frozenset(tests)

    def add_test_command(self, test_command):
        self.tests = frozenset([TestCommand(self, test_command)])

    def add_restrictions(self, restrictions):
        restrictions = re.split(r'\s*,?\s+', restrictions)
        self.restrictions = frozenset(restrictions)

    def add_features(self, features):
        features = re.split(r'\s*,?\s+', features)
        self.features = frozenset(features)

    def add_depends(self, depends):
        self.depends = depends

    def add_tests_directory(self, path):
        self.tests_directory = path


def copy_build_tree():
    rw_build_tree = tempfile.mkdtemp(prefix='sadt-rwbt.')
    print('sadt: info: copying build tree to {tree}'.format(tree=rw_build_tree), file=sys.stderr)
    ipc.check_call(['cp', '-a', '.', rw_build_tree])
    return rw_build_tree


def main():
    # TODO: refactor main function
    # pylint: disable=too-many-branches,too-many-statements,too-many-locals,too-many-nested-blocks
    parser = argparse.ArgumentParser(description=__doc__.strip())
    parser.add_argument('-v', '--verbose',
                        action='store_true', help='verbose output')
    parser.add_argument('-b', '--built-source-tree', action='store_true',
                        help='assume built source tree')
    parser.add_argument('--ignore-restrictions', metavar='<restr>[,<restr>...]',
                        help='ignore specified restrictions', default='')
    parser.add_argument('tests', metavar='<test-name>',
                        nargs='*', help='tests to run')
    options = parser.parse_args()
    options.tests = frozenset(options.tests)
    options.ignore_restrictions = frozenset(
        options.ignore_restrictions.split(','))
    binary_packages = set()
    build_depends = []
    try:
        file = open('debian/control', encoding='UTF-8')
    except IOError as exc:
        if exc.errno == errno.ENOENT:
            print('sadt: error: cannot find debian/control', file=sys.stderr)
            sys.exit(1)
        raise
    with file:
        for n, para in enumerate(deb822.Packages.iter_paragraphs(file)):
            if n == 0:
                # FIXME statement with no effect
                # para['Source']
                for field in 'Build-Depends', 'Build-Depends-Indep':
                    try:
                        build_depends += parse_relations(para[field])
                    except KeyError:
                        continue
            else:
                binary_packages.add(para['Package'])
    test_groups = []
    try:
        file = open('debian/tests/control', encoding='UTF-8')
    except IOError as exc:
        if exc.errno == errno.ENOENT:
            print('sadt: error: cannot find debian/tests/control', file=sys.stderr)
            sys.exit(1)
        raise
    with file:
        for para in deb822.Packages.iter_paragraphs(file):
            group = TestGroup()
            for key, value in para.items():
                lkey = key.lower().replace('-', '_')
                try:
                    method = getattr(group, 'add_' + lkey)
                except AttributeError:
                    print('sadt: warning: unknown field {field}, skipping the whole paragraph'
                          .format(field=key), file=sys.stderr)
                    group = None
                    break
                method(value)
            if group is not None:
                group.expand_depends(binary_packages, build_depends)
                test_groups += [group]
    failures = []
    flakes = []
    n_skip = n_ok = 0
    progress = VerboseProgress() if options.verbose else DefaultProgress()
    rw_build_tree = None
    try:
        for group in test_groups:
            for test in group:
                if options.tests and test.name not in options.tests:
                    continue
                try:
                    if rw_build_tree is None:
                        try:
                            group_options = group.check()
                        except Skip:
                            pass
                        else:
                            if group_options.rw_build_tree_needed:
                                rw_build_tree = copy_build_tree()
                                assert rw_build_tree is not None
                    group.run(
                        test,
                        progress=progress,
                        ignored_restrictions=options.ignore_restrictions,
                        rw_build_tree=rw_build_tree,
                        built_source_tree=options.built_source_tree
                    )
                except Skip:
                    n_skip += 1
                except Fail as exc:
                    failures += [(test, exc)]
                except Flaky as exc:
                    flakes += [(test, exc)]
                else:
                    n_ok += 1
    finally:
        progress.close()
    n_fail = len(failures)
    n_flake = len(flakes)
    n_test = n_fail + n_flake + n_skip + n_ok
    if failures:
        for name, exception in failures:
            print('=' * 70)
            print('FAIL: {test} ({reason})'.format(
                test=name, reason=exception.args[1]))
    if flakes:
        for name, exception in flakes:
            print('=' * 70)
            print('FLAKY: {test} ({reason})'.format(
                test=name, reason=exception.args[1]))
    print()
    fmt_message = ['tests={n}'.format(n=n_test)]
    if n_skip > 0:
        fmt_message += ['skipped={n}'.format(n=n_skip)]
    if n_fail > 0:
        fmt_message += ['failures={n}'.format(n=n_fail)]
    if n_flake > 0:
        fmt_message += ['flaky={n}'.format(n=n_flake)]
    if fmt_message:
        extra_message = ' ({msg})'.format(msg=', '.join(fmt_message))
    else:
        extra_message = ''
    message = ('OK' if n_fail == 0 else 'FAILED') + extra_message
    print(message)
    if rw_build_tree is not None:
        shutil.rmtree(rw_build_tree)
    sys.exit(n_fail > 0)


if __name__ == '__main__':
    main()

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