# This file is part of h5py, a Python interface to the HDF5 library.
#
# http://www.h5py.org
#
# Copyright 2008-2013 Andrew Collette and contributors
#
# License:  Standard 3-clause BSD; see "license.txt" for full license terms
#           and contributor agreement.

"""
    File object test module.

    Tests all aspects of File objects, including their creation.
"""

import pytest
import os
import stat
import pickle
import tempfile
import subprocess
import sys

from .common import ut, TestCase, UNICODE_FILENAMES, closed_tempfile
from h5py._hl.files import direct_vfd
from h5py import File
import h5py
from .. import h5
import pathlib


class TestFileOpen(TestCase):

    """
        Feature: Opening files with Python-style modes.
    """

    def test_default(self):
        """ Default semantics in the presence or absence of a file """
        fname = self.mktemp()

        # No existing file; error
        with pytest.raises(FileNotFoundError):
            with File(fname):
                pass

        # Existing readonly file; open read-only
        with File(fname, 'w'):
            pass
        os.chmod(fname, stat.S_IREAD)
        try:
            with File(fname) as f:
                self.assertTrue(f)
                self.assertEqual(f.mode, 'r')
        finally:
            os.chmod(fname, stat.S_IWRITE)

        # File exists but is not HDF5; raise OSError
        with open(fname, 'wb') as f:
            f.write(b'\x00')
        with self.assertRaises(OSError):
            File(fname)

    def test_create(self):
        """ Mode 'w' opens file in overwrite mode """
        fname = self.mktemp()
        fid = File(fname, 'w')
        self.assertTrue(fid)
        fid.create_group('foo')
        fid.close()
        fid = File(fname, 'w')
        self.assertNotIn('foo', fid)
        fid.close()

    def test_create_exclusive(self):
        """ Mode 'w-' opens file in exclusive mode """
        fname = self.mktemp()
        fid = File(fname, 'w-')
        self.assertTrue(fid)
        fid.close()
        with self.assertRaises(FileExistsError):
            File(fname, 'w-')

    def test_append(self):
        """ Mode 'a' opens file in append/readwrite mode, creating if necessary """
        fname = self.mktemp()
        fid = File(fname, 'a')
        try:
            self.assertTrue(fid)
            fid.create_group('foo')
            assert 'foo' in fid
        finally:
            fid.close()
        fid = File(fname, 'a')
        try:
            assert 'foo' in fid
            fid.create_group('bar')
            assert 'bar' in fid
        finally:
            fid.close()

        os.chmod(fname, stat.S_IREAD)  # Make file read-only
        try:
            with pytest.raises(PermissionError):
                File(fname, 'a')
        finally:
            # Make it writable again so it can be deleted on Windows
            os.chmod(fname, stat.S_IREAD | stat.S_IWRITE)

    def test_readonly(self):
        """ Mode 'r' opens file in readonly mode """
        fname = self.mktemp()
        fid = File(fname, 'w')
        fid.close()
        self.assertFalse(fid)
        fid = File(fname, 'r')
        self.assertTrue(fid)
        with self.assertRaises(ValueError):
            fid.create_group('foo')
        fid.close()

    def test_readwrite(self):
        """ Mode 'r+' opens existing file in readwrite mode """
        fname = self.mktemp()
        fid = File(fname, 'w')
        fid.create_group('foo')
        fid.close()
        fid = File(fname, 'r+')
        assert 'foo' in fid
        fid.create_group('bar')
        assert 'bar' in fid
        fid.close()

    def test_nonexistent_file(self):
        """ Modes 'r' and 'r+' do not create files """
        fname = self.mktemp()
        with self.assertRaises(FileNotFoundError):
            File(fname, 'r')
        with self.assertRaises(FileNotFoundError):
            File(fname, 'r+')

    def test_invalid_mode(self):
        """ Invalid modes raise ValueError """
        with self.assertRaises(ValueError):
            File(self.mktemp(), 'mongoose')


class TestSpaceStrategy(TestCase):

    """
        Feature: Create file with specified file space strategy
    """

    def test_create_with_space_strategy(self):
        """ Create file with file space strategy """
        fname = self.mktemp()
        fid = File(fname, 'w', fs_strategy="page",
                   fs_persist=True, fs_threshold=100)
        self.assertTrue(fid)
        # Unable to set file space strategy of an existing file
        with self.assertRaises(ValueError):
            File(fname, 'a', fs_strategy="page")
        # Invalid file space strategy type
        with self.assertRaises(ValueError):
            File(self.mktemp(), 'w', fs_strategy="invalid")

        dset = fid.create_dataset('foo', (100,), dtype='uint8')
        dset[...] = 1
        dset = fid.create_dataset('bar', (100,), dtype='uint8')
        dset[...] = 1
        del fid['foo']
        fid.close()

        fid = File(fname, 'a')
        plist = fid.id.get_create_plist()
        fs_strat = plist.get_file_space_strategy()
        assert(fs_strat[0] == 1)
        assert(fs_strat[1] == True)
        assert(fs_strat[2] == 100)

        dset = fid.create_dataset('foo2', (100,), dtype='uint8')
        dset[...] = 1
        fid.close()


@pytest.mark.mpi_skip
class TestPageBuffering(TestCase):
    """
        Feature: Use page buffering
    """

    def test_only_with_page_strategy(self):
        """Allow page buffering only with fs_strategy="page".
        """
        fname = self.mktemp()
        with File(fname, mode='w', fs_strategy='page', page_buf_size=16*1024):
            pass
        with self.assertRaises(OSError):
            File(fname, mode='w', page_buf_size=16*1024)
        with self.assertRaises(OSError):
            File(fname, mode='w', fs_strategy='fsm', page_buf_size=16*1024)
        with self.assertRaises(OSError):
            File(fname, mode='w', fs_strategy='aggregate', page_buf_size=16*1024)

    def test_check_page_buf_size(self):
        """Verify set page buffer size, and minimum meta and raw eviction criteria."""
        fname = self.mktemp()
        pbs = 16 * 1024
        mm = 19
        mr = 67
        with File(fname, mode='w', fs_strategy='page',
                  page_buf_size=pbs, min_meta_keep=mm, min_raw_keep=mr) as f:
            fapl = f.id.get_access_plist()
            self.assertEqual(fapl.get_page_buffer_size(), (pbs, mm, mr))

    def test_too_small_pbs(self):
        """Page buffer size must be greater than file space page size."""
        fname = self.mktemp()
        fsp = 16 * 1024
        with File(fname, mode='w', fs_strategy='page', fs_page_size=fsp):
            pass
        with self.assertRaises(OSError):
            File(fname, mode="r", page_buf_size=fsp-1)

    def test_actual_pbs(self):
        """Verify actual page buffer size."""
        fname = self.mktemp()
        fsp = 16 * 1024
        pbs = 2 * fsp
        with File(fname, mode='w', fs_strategy='page', fs_page_size=fsp):
            pass
        with File(fname, mode='r', page_buf_size=pbs-1) as f:
            fapl = f.id.get_access_plist()
            self.assertEqual(fapl.get_page_buffer_size()[0], fsp)


class TestModes(TestCase):

    """
        Feature: File mode can be retrieved via file.mode
    """

    def test_mode_attr(self):
        """ Mode equivalent can be retrieved via property """
        fname = self.mktemp()
        with File(fname, 'w') as f:
            self.assertEqual(f.mode, 'r+')
        with File(fname, 'r') as f:
            self.assertEqual(f.mode, 'r')

    def test_mode_external(self):
        """ Mode property works for files opened via external links

        Issue 190.
        """
        fname1 = self.mktemp()
        fname2 = self.mktemp()

        f1 = File(fname1, 'w')
        f1.close()

        f2 = File(fname2, 'w')
        try:
            f2['External'] = h5py.ExternalLink(fname1, '/')
            f3 = f2['External'].file
            self.assertEqual(f3.mode, 'r+')
        finally:
            f2.close()
            f3.close()

        f2 = File(fname2, 'r')
        try:
            f3 = f2['External'].file
            self.assertEqual(f3.mode, 'r')
        finally:
            f2.close()
            f3.close()


class TestDrivers(TestCase):

    """
        Feature: Files can be opened with low-level HDF5 drivers. Does not
        include MPI drivers (see bottom).
    """

    @ut.skipUnless(os.name == 'posix', "Stdio driver is supported on posix")
    def test_stdio(self):
        """ Stdio driver is supported on posix """
        fid = File(self.mktemp(), 'w', driver='stdio')
        self.assertTrue(fid)
        self.assertEqual(fid.driver, 'stdio')
        fid.close()

        # Testing creation with append flag
        fid = File(self.mktemp(), 'a', driver='stdio')
        self.assertTrue(fid)
        self.assertEqual(fid.driver, 'stdio')
        fid.close()

    @ut.skipUnless(direct_vfd,
                   "DIRECT driver is supported on Linux if hdf5 is "
                   "built with the appriorate flags.")
    def test_direct(self):
        """ DIRECT driver is supported on Linux"""
        fid = File(self.mktemp(), 'w', driver='direct')
        self.assertTrue(fid)
        self.assertEqual(fid.driver, 'direct')
        default_fapl = fid.id.get_access_plist().get_fapl_direct()
        fid.close()

        # Testing creation with append flag
        fid = File(self.mktemp(), 'a', driver='direct')
        self.assertTrue(fid)
        self.assertEqual(fid.driver, 'direct')
        fid.close()

        # 2022/02/26: hnmaarrfk
        # I'm actually not too sure of the restriction on the
        # different valid block_sizes and cbuf_sizes on different hardware
        # platforms.
        #
        # I've learned a few things:
        #    * cbuf_size: Copy buffer size must be a multiple of block size
        # The alignment (on my platform x86-64bit with an NVMe SSD
        # could be an integer multiple of 512
        #
        # To allow HDF5 to do the heavy lifting for different platform,
        # We didn't provide any argumnets to the first call
        # and obtained HDF5's default values there.

        # Testing creation with a few different property lists
        for alignment, block_size, cbuf_size in [
                default_fapl,
                (default_fapl[0], default_fapl[1], 3 * default_fapl[1]),
                (default_fapl[0] * 2, default_fapl[1], 3 * default_fapl[1]),
                (default_fapl[0], 2 * default_fapl[1], 6 * default_fapl[1]),
                ]:
            with File(self.mktemp(), 'w', driver='direct',
                      alignment=alignment,
                      block_size=block_size,
                      cbuf_size=cbuf_size) as fid:
                actual_fapl = fid.id.get_access_plist().get_fapl_direct()
                actual_alignment = actual_fapl[0]
                actual_block_size = actual_fapl[1]
                actual_cbuf_size = actual_fapl[2]
                assert actual_alignment == alignment
                assert actual_block_size == block_size
                assert actual_cbuf_size == actual_cbuf_size

    @ut.skipUnless(os.name == 'posix', "Sec2 driver is supported on posix")
    def test_sec2(self):
        """ Sec2 driver is supported on posix """
        fid = File(self.mktemp(), 'w', driver='sec2')
        self.assertTrue(fid)
        self.assertEqual(fid.driver, 'sec2')
        fid.close()

        # Testing creation with append flag
        fid = File(self.mktemp(), 'a', driver='sec2')
        self.assertTrue(fid)
        self.assertEqual(fid.driver, 'sec2')
        fid.close()

    def test_core(self):
        """ Core driver is supported (no backing store) """
        fname = self.mktemp()
        fid = File(fname, 'w', driver='core', backing_store=False)
        self.assertTrue(fid)
        self.assertEqual(fid.driver, 'core')
        fid.close()
        self.assertFalse(os.path.exists(fname))

        # Testing creation with append flag
        fid = File(self.mktemp(), 'a', driver='core')
        self.assertTrue(fid)
        self.assertEqual(fid.driver, 'core')
        fid.close()

    def test_backing(self):
        """ Core driver saves to file when backing store used """
        fname = self.mktemp()
        fid = File(fname, 'w', driver='core', backing_store=True)
        fid.create_group('foo')
        fid.close()
        fid = File(fname, 'r')
        assert 'foo' in fid
        fid.close()
        # keywords for other drivers are invalid when using the default driver
        with self.assertRaises(TypeError):
            File(fname, 'w', backing_store=True)

    def test_readonly(self):
        """ Core driver can be used to open existing files """
        fname = self.mktemp()
        fid = File(fname, 'w')
        fid.create_group('foo')
        fid.close()
        fid = File(fname, 'r', driver='core')
        self.assertTrue(fid)
        assert 'foo' in fid
        with self.assertRaises(ValueError):
            fid.create_group('bar')
        fid.close()

    def test_blocksize(self):
        """ Core driver supports variable block size """
        fname = self.mktemp()
        fid = File(fname, 'w', driver='core', block_size=1024,
                   backing_store=False)
        self.assertTrue(fid)
        fid.close()

    def test_split(self):
        """ Split stores metadata in a separate file """
        fname = self.mktemp()
        fid = File(fname, 'w', driver='split')
        fid.close()
        self.assertTrue(os.path.exists(fname + '-m.h5'))
        fid = File(fname, 'r', driver='split')
        self.assertTrue(fid)
        fid.close()

    def test_fileobj(self):
        """ Python file object driver is supported """
        tf = tempfile.TemporaryFile()
        fid = File(tf, 'w', driver='fileobj')
        self.assertTrue(fid)
        self.assertEqual(fid.driver, 'fileobj')
        fid.close()
        # Driver must be 'fileobj' for file-like object if specified
        with self.assertRaises(ValueError):
            File(tf, 'w', driver='core')

    # TODO: family driver tests



class TestNewLibver(TestCase):

    """
        Feature: File format compatibility bounds can be specified when
        opening a file.
    """

    @classmethod
    def setUpClass(cls):
        super().setUpClass()

        # Current latest library bound label
        if h5py.version.hdf5_version_tuple < (1, 11, 4):
            cls.latest = 'v110'
        elif h5py.version.hdf5_version_tuple < (1, 13, 0):
            cls.latest = 'v112'
        else:
            cls.latest = 'v114'

    def test_default(self):
        """ Opening with no libver arg """
        f = File(self.mktemp(), 'w')
        self.assertEqual(f.libver, ('earliest', self.latest))
        f.close()

    def test_single(self):
        """ Opening with single libver arg """
        f = File(self.mktemp(), 'w', libver='latest')
        self.assertEqual(f.libver, (self.latest, self.latest))
        f.close()

    def test_single_v108(self):
        """ Opening with "v108" libver arg """
        f = File(self.mktemp(), 'w', libver='v108')
        self.assertEqual(f.libver, ('v108', self.latest))
        f.close()

    def test_single_v110(self):
        """ Opening with "v110" libver arg """
        f = File(self.mktemp(), 'w', libver='v110')
        self.assertEqual(f.libver, ('v110', self.latest))
        f.close()

    @ut.skipIf(h5py.version.hdf5_version_tuple < (1, 11, 4),
               'Requires HDF5 1.11.4 or later')
    def test_single_v112(self):
        """ Opening with "v112" libver arg """
        f = File(self.mktemp(), 'w', libver='v112')
        self.assertEqual(f.libver, ('v112', self.latest))
        f.close()

    def test_multiple(self):
        """ Opening with two libver args """
        f = File(self.mktemp(), 'w', libver=('earliest', 'v108'))
        self.assertEqual(f.libver, ('earliest', 'v108'))
        f.close()

    def test_none(self):
        """ Omitting libver arg results in maximum compatibility """
        f = File(self.mktemp(), 'w')
        self.assertEqual(f.libver, ('earliest', self.latest))
        f.close()


class TestUserblock(TestCase):

    """
        Feature: Files can be create with user blocks
    """

    def test_create_blocksize(self):
        """ User blocks created with w, w-, x and properties work correctly """
        f = File(self.mktemp(), 'w-', userblock_size=512)
        try:
            self.assertEqual(f.userblock_size, 512)
        finally:
            f.close()

        f = File(self.mktemp(), 'x', userblock_size=512)
        try:
            self.assertEqual(f.userblock_size, 512)
        finally:
            f.close()

        f = File(self.mktemp(), 'w', userblock_size=512)
        try:
            self.assertEqual(f.userblock_size, 512)
        finally:
            f.close()
        # User block size must be an integer
        with self.assertRaises(ValueError):
            File(self.mktemp(), 'w', userblock_size='non')

    def test_write_only(self):
        """ User block only allowed for write """
        name = self.mktemp()
        f = File(name, 'w')
        f.close()

        with self.assertRaises(ValueError):
            f = h5py.File(name, 'r', userblock_size=512)

        with self.assertRaises(ValueError):
            f = h5py.File(name, 'r+', userblock_size=512)

    def test_match_existing(self):
        """ User block size must match that of file when opening for append """
        name = self.mktemp()
        f = File(name, 'w', userblock_size=512)
        f.close()

        with self.assertRaises(ValueError):
            f = File(name, 'a', userblock_size=1024)

        f = File(name, 'a', userblock_size=512)
        try:
            self.assertEqual(f.userblock_size, 512)
        finally:
            f.close()

    def test_power_of_two(self):
        """ User block size must be a power of 2 and at least 512 """
        name = self.mktemp()

        with self.assertRaises(ValueError):
            f = File(name, 'w', userblock_size=128)

        with self.assertRaises(ValueError):
            f = File(name, 'w', userblock_size=513)

        with self.assertRaises(ValueError):
            f = File(name, 'w', userblock_size=1023)

    def test_write_block(self):
        """ Test that writing to a user block does not destroy the file """
        name = self.mktemp()

        f = File(name, 'w', userblock_size=512)
        f.create_group("Foobar")
        f.close()

        pyfile = open(name, 'r+b')
        try:
            pyfile.write(b'X' * 512)
        finally:
            pyfile.close()

        f = h5py.File(name, 'r')
        try:
            assert "Foobar" in f
        finally:
            f.close()

        pyfile = open(name, 'rb')
        try:
            self.assertEqual(pyfile.read(512), b'X' * 512)
        finally:
            pyfile.close()


class TestContextManager(TestCase):

    """
        Feature: File objects can be used as context managers
    """

    def test_context_manager(self):
        """ File objects can be used in with statements """
        with File(self.mktemp(), 'w') as fid:
            self.assertTrue(fid)
        self.assertTrue(not fid)


@ut.skipIf(not UNICODE_FILENAMES, "Filesystem unicode support required")
class TestUnicode(TestCase):

    """
        Feature: Unicode filenames are supported
    """

    def test_unicode(self):
        """ Unicode filenames can be used, and retrieved properly via .filename
        """
        fname = self.mktemp(prefix=chr(0x201a))
        fid = File(fname, 'w')
        try:
            self.assertEqual(fid.filename, fname)
            self.assertIsInstance(fid.filename, str)
        finally:
            fid.close()

    def test_unicode_hdf5_python_consistent(self):
        """ Unicode filenames can be used, and seen correctly from python
        """
        fname = self.mktemp(prefix=chr(0x201a))
        with File(fname, 'w') as f:
            self.assertTrue(os.path.exists(fname))

    def test_nonexistent_file_unicode(self):
        """
        Modes 'r' and 'r+' do not create files even when given unicode names
        """
        fname = self.mktemp(prefix=chr(0x201a))
        with self.assertRaises(IOError):
            File(fname, 'r')
        with self.assertRaises(IOError):
            File(fname, 'r+')


class TestFileProperty(TestCase):

    """
        Feature: A File object can be retrieved from any child object,
        via the .file property
    """

    def test_property(self):
        """ File object can be retrieved from subgroup """
        fname = self.mktemp()
        hfile = File(fname, 'w')
        try:
            hfile2 = hfile['/'].file
            self.assertEqual(hfile, hfile2)
        finally:
            hfile.close()

    def test_close(self):
        """ All retrieved File objects are closed at the same time """
        fname = self.mktemp()
        hfile = File(fname, 'w')
        grp = hfile.create_group('foo')
        hfile2 = grp.file
        hfile3 = hfile['/'].file
        hfile2.close()
        self.assertFalse(hfile)
        self.assertFalse(hfile2)
        self.assertFalse(hfile3)

    def test_mode(self):
        """ Retrieved File objects have a meaningful mode attribute """
        hfile = File(self.mktemp(), 'w')
        try:
            grp = hfile.create_group('foo')
            self.assertEqual(grp.file.mode, hfile.mode)
        finally:
            hfile.close()


class TestClose(TestCase):

    """
        Feature: Files can be closed
    """

    def test_close(self):
        """ Close file via .close method """
        fid = File(self.mktemp(), 'w')
        self.assertTrue(fid)
        fid.close()
        self.assertFalse(fid)

    def test_closed_file(self):
        """ Trying to modify closed file raises ValueError """
        fid = File(self.mktemp(), 'w')
        fid.close()
        with self.assertRaises(ValueError):
            fid.create_group('foo')

    def test_close_multiple_default_driver(self):
        fname = self.mktemp()
        f = h5py.File(fname, 'w')
        f.create_group("test")
        f.close()
        f.close()


class TestFlush(TestCase):

    """
        Feature: Files can be flushed
    """

    def test_flush(self):
        """ Flush via .flush method """
        fid = File(self.mktemp(), 'w')
        fid.flush()
        fid.close()


class TestRepr(TestCase):

    """
        Feature: File objects provide a helpful __repr__ string
    """

    def test_repr(self):
        """ __repr__ behaves itself when files are open and closed """
        fid = File(self.mktemp(), 'w')
        self.assertIsInstance(repr(fid), str)
        fid.close()
        self.assertIsInstance(repr(fid), str)


class TestFilename(TestCase):

    """
        Feature: The name of a File object can be retrieved via .filename
    """

    def test_filename(self):
        """ .filename behaves properly for string data """
        fname = self.mktemp()
        fid = File(fname, 'w')
        try:
            self.assertEqual(fid.filename, fname)
            self.assertIsInstance(fid.filename, str)
        finally:
            fid.close()


class TestCloseInvalidatesOpenObjectIDs(TestCase):

    """
        Ensure that closing a file invalidates object IDs, as appropriate
    """

    def test_close(self):
        """ Closing a file invalidates any of the file's open objects """
        with File(self.mktemp(), 'w') as f1:
            g1 = f1.create_group('foo')
            self.assertTrue(bool(f1.id))
            self.assertTrue(bool(g1.id))
            f1.close()
            self.assertFalse(bool(f1.id))
            self.assertFalse(bool(g1.id))
        with File(self.mktemp(), 'w') as f2:
            g2 = f2.create_group('foo')
            self.assertTrue(bool(f2.id))
            self.assertTrue(bool(g2.id))
            self.assertFalse(bool(f1.id))
            self.assertFalse(bool(g1.id))

    def test_close_one_handle(self):
        fname = self.mktemp()
        with File(fname, 'w') as f:
            f.create_group('foo')

        f1 = File(fname)
        f2 = File(fname)
        g1 = f1['foo']
        g2 = f2['foo']
        assert g1.id.valid
        assert g2.id.valid
        f1.close()
        assert not g1.id.valid
        # Closing f1 shouldn't close f2 or objects belonging to it
        assert f2.id.valid
        assert g2.id.valid

        f2.close()
        assert not f2.id.valid
        assert not g2.id.valid


class TestPathlibSupport(TestCase):

    """
        Check that h5py doesn't break on pathlib
    """
    def test_pathlib_accepted_file(self):
        """ Check that pathlib is accepted by h5py.File """
        with closed_tempfile() as f:
            path = pathlib.Path(f)
            with File(path, 'w') as f2:
                self.assertTrue(True)

    def test_pathlib_name_match(self):
        """ Check that using pathlib does not affect naming """
        with closed_tempfile() as f:
            path = pathlib.Path(f)
            with File(path, 'w') as h5f1:
                pathlib_name = h5f1.filename
            with File(f, 'w') as h5f2:
                normal_name = h5f2.filename
            self.assertEqual(pathlib_name, normal_name)


class TestPickle(TestCase):
    """Check that h5py.File can't be pickled"""
    def test_dump_error(self):
        with File(self.mktemp(), 'w') as f1:
            with self.assertRaises(TypeError):
                pickle.dumps(f1)


# unittest doesn't work with pytest fixtures (and possibly other features),
# hence no subclassing TestCase
@pytest.mark.mpi
@pytest.mark.skip(reason="fixture 'mpi_file_name' not present")
class TestMPI:
    def test_mpio(self, mpi_file_name):
        """ MPIO driver and options """
        from mpi4py import MPI

        with File(mpi_file_name, 'w', driver='mpio', comm=MPI.COMM_WORLD) as f:
            assert f
            assert f.driver == 'mpio'

    def test_mpio_append(self, mpi_file_name):
        """ Testing creation of file with append """
        from mpi4py import MPI

        with File(mpi_file_name, 'a', driver='mpio', comm=MPI.COMM_WORLD) as f:
            assert f
            assert f.driver == 'mpio'

    def test_mpi_atomic(self, mpi_file_name):
        """ Enable atomic mode for MPIO driver """
        from mpi4py import MPI

        with File(mpi_file_name, 'w', driver='mpio', comm=MPI.COMM_WORLD) as f:
            assert not f.atomic
            f.atomic = True
            assert f.atomic

    def test_close_multiple_mpio_driver(self, mpi_file_name):
        """ MPIO driver and options """
        from mpi4py import MPI

        f = File(mpi_file_name, 'w', driver='mpio', comm=MPI.COMM_WORLD)
        f.create_group("test")
        f.close()
        f.close()


class TestSWMRMode(TestCase):

    """
        Feature: Create file that switches on SWMR mode
    """

    def test_file_mode_generalizes(self):
        fname = self.mktemp()
        fid = File(fname, 'w', libver='latest')
        g = fid.create_group('foo')
        # fid and group member file attribute should have the same mode
        assert fid.mode == g.file.mode == 'r+'
        fid.swmr_mode = True
        # fid and group member file attribute should still be 'r+'
        # even though file intent has changed
        assert fid.mode == g.file.mode == 'r+'
        fid.close()

    def test_swmr_mode_consistency(self):
        fname = self.mktemp()
        fid = File(fname, 'w', libver='latest')
        g = fid.create_group('foo')
        assert fid.swmr_mode == g.file.swmr_mode == False
        fid.swmr_mode = True
        # This setter should affect both fid and group member file attribute
        assert fid.swmr_mode == g.file.swmr_mode == True
        fid.close()


@pytest.mark.skipif(
    h5py.version.hdf5_version_tuple < (1, 12, 1) and (
    h5py.version.hdf5_version_tuple[:2] != (1, 10) or h5py.version.hdf5_version_tuple[2] < 7),
    reason="Requires HDF5 >= 1.12.1 or 1.10.x >= 1.10.7")
@pytest.mark.skipif("HDF5_USE_FILE_LOCKING" in os.environ,
                    reason="HDF5_USE_FILE_LOCKING env. var. is set")
class TestFileLocking:
    """Test h5py.File file locking option"""

    def test_reopen(self, tmp_path):
        """Test file locking when opening twice the same file"""
        fname = tmp_path / "test.h5"

        with h5py.File(fname, mode="w", locking=True) as f:
            f.flush()

            # Opening same file in same process without locking is expected to fail
            with pytest.raises(OSError):
                with h5py.File(fname, mode="r", locking=False) as h5f_read:
                    pass

            with h5py.File(fname, mode="r", locking=True) as h5f_read:
                pass

            with h5py.File(fname, mode="r", locking='best-effort') as h5f_read:
                pass

    def test_unsupported_locking(self, tmp_path):
        """Test with erroneous file locking value"""
        fname = tmp_path / "test.h5"
        with pytest.raises(ValueError):
            with h5py.File(fname, mode="r", locking='unsupported-value') as h5f_read:
                pass

    def test_multiprocess(self, tmp_path):
        """Test file locking option from different concurrent processes"""
        fname = tmp_path / "test.h5"

        def open_in_subprocess(filename, mode, locking):
            """Open HDF5 file in a subprocess and return True on success"""
            h5py_import_dir = str(pathlib.Path(h5py.__file__).parent.parent)

            process = subprocess.run(
                [
                    sys.executable,
                    "-c",
                    f"""
import sys
sys.path.insert(0, {h5py_import_dir!r})
import h5py
f = h5py.File({str(filename)!r}, mode={mode!r}, locking={locking})
                    """,
                ],
                capture_output=True)
            return process.returncode == 0 and not process.stderr

        # Create test file
        with h5py.File(fname, mode="w", locking=True) as f:
            f["data"] = 1

        with h5py.File(fname, mode="r", locking=False) as f:
            # Opening in write mode with locking is expected to work
            assert open_in_subprocess(fname, mode="w", locking=True)


def test_close_gc(writable_file):
    # https://github.com/h5py/h5py/issues/1852
    for i in range(100):
        writable_file[str(i)] = []

    filename = writable_file.filename
    writable_file.close()

    # Ensure that Python's garbage collection doesn't interfere with closing
    # a file. Try a few times - the problem is not 100% consistent, but
    # normally showed up on the 1st or 2nd iteration for me. -TAK, 2021
    for i in range(10):
        with h5py.File(filename, 'r') as f:
            refs = [d.id for d in f.values()]
            refs.append(refs)   # Make a reference cycle so GC is involved
            del refs  # GC is likely to fire while closing the file
