view tests/test-parseindex2.py @ 30446:b324b4e431e5

posix: give checkexec a fast path; keep the check files and test read only

Before, Mercurial would create a new temporary file every time, stat it, change
its exec mode, stat it again, and delete it. Most of this dance was done to
handle the rare and not-so-essential case of VFAT mounts on unix. The cost of
that was paid by the much more common and important case of using normal file
systems.

Instead, try to create and preserve .hg/cache/checkisexec and
.hg/cache/checknoexec with and without exec flag set. If the files exist and
have correct exec flags set, we can conclude that that file system supports the
exec flag. Best case, the whole exec check can thus be done with two stat
calls. Worst case, we delete the wrong files and check as usual. That will be
because temporary loss of exec bit or on file systems without support for the
exec bit. In that case we check as we did before, with the additional overhead
of one extra stat call.

It is possible that this different test algorithm in some cases on odd file
systems will give different behaviour. Again, I think it will be rare and
special cases and I think it is worth the risk.

test-clone.t happens to show the situation where checkisexec is left behind
from the old style check, while checknoexec only will be created next time a
exec check will be performed.

"""This unit test primarily tests parsers.parse_index2().

It also checks certain aspects of the parsers module as a whole.
"""

from __future__ import absolute_import, print_function

import struct
import subprocess
import sys

from mercurial.node import (
    nullid,
    nullrev,
)
from mercurial import (
    parsers,
)

# original python implementation
def gettype(q):
    return int(q & 0xFFFF)

def offset_type(offset, type):
    return long(long(offset) << 16 | type)

indexformatng = ">Qiiiiii20s12x"

def py_parseindex(data, inline) :
    s = 64
    cache = None
    index = []
    nodemap = {nullid: nullrev}
    n = off = 0

    l = len(data) - s
    append = index.append
    if inline:
        cache = (0, data)
        while off <= l:
            e = struct.unpack(indexformatng, data[off:off + s])
            nodemap[e[7]] = n
            append(e)
            n += 1
            if e[1] < 0:
                break
            off += e[1] + s
    else:
        while off <= l:
            e = struct.unpack(indexformatng, data[off:off + s])
            nodemap[e[7]] = n
            append(e)
            n += 1
            off += s

    e = list(index[0])
    type = gettype(e[0])
    e[0] = offset_type(0, type)
    index[0] = tuple(e)

    # add the magic null revision at -1
    index.append((0, 0, 0, -1, -1, -1, -1, nullid))

    return index, cache

data_inlined = '\x00\x01\x00\x01\x00\x00\x00\x00\x00\x00\x01\x8c' \
    '\x00\x00\x04\x07\x00\x00\x00\x00\x00\x00\x15\x15\xff\xff\xff' \
    '\xff\xff\xff\xff\xff\xebG\x97\xb7\x1fB\x04\xcf\x13V\x81\tw\x1b' \
    'w\xdduR\xda\xc6\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00' \
    'x\x9c\x9d\x93?O\xc30\x10\xc5\xf7|\x8a\xdb\x9a\xa8m\x06\xd8*\x95' \
    '\x81B\xa1\xa2\xa2R\xcb\x86Pd\x9a\x0b5$vd_\x04\xfd\xf6\x9c\xff@' \
    '\x11!\x0b\xd9\xec\xf7\xbbw\xe7gG6\xad6\x04\xdaN\xc0\x92\xa0$)' \
    '\xb1\x82\xa2\xd1%\x16\xa4\x8b7\xa9\xca\xd4-\xb2Y\x02\xfc\xc9' \
    '\xcaS\xf9\xaeX\xed\xb6\xd77Q\x02\x83\xd4\x19\xf5--Y\xea\xe1W' \
    '\xab\xed\x10\xceR\x0f_\xdf\xdf\r\xe1,\xf5\xf0\xcb\xf5 \xceR\x0f' \
    '_\xdc\x0e\x0e\xc3R\x0f_\xae\x96\x9b!\x9e\xa5\x1e\xbf\xdb,\x06' \
    '\xc7q\x9a/\x88\x82\xc3B\xea\xb5\xb4TJ\x93\xb6\x82\x0e\xe16\xe6' \
    'KQ\xdb\xaf\xecG\xa3\xd1 \x01\xd3\x0b_^\xe8\xaa\xa0\xae\xad\xd1' \
    '&\xbef\x1bz\x08\xb0|\xc9Xz\x06\xf6Z\x91\x90J\xaa\x17\x90\xaa' \
    '\xd2\xa6\x11$5C\xcf\xba#\xa0\x03\x02*2\x92-\xfc\xb1\x94\xdf\xe2' \
    '\xae\xb8\'m\x8ey0^\x85\xd3\x82\xb4\xf0`:\x9c\x00\x8a\xfd\x01' \
    '\xb0\xc6\x86\x8b\xdd\xae\x80\xf3\xa9\x9fd\x16\n\x00R%\x1a\x06' \
    '\xe9\xd8b\x98\x1d\xf4\xf3+\x9bf\x01\xd8p\x1b\xf3.\xed\x9f^g\xc3' \
    '^\xd9W81T\xdb\xd5\x04sx|\xf2\xeb\xd6`%?x\xed"\x831\xbf\xf3\xdc' \
    'b\xeb%gaY\xe1\xad\x9f\xb9f\'1w\xa9\xa5a\x83s\x82J\xb98\xbc4\x8b' \
    '\x83\x00\x9f$z\xb8#\xa5\xb1\xdf\x98\xd9\xec\x1b\x89O\xe3Ts\x9a4' \
    '\x17m\x8b\xfc\x8f\xa5\x95\x9a\xfc\xfa\xed,\xe5|\xa1\xfe\x15\xb9' \
    '\xbc\xb2\x93\x1f\xf2\x95\xff\xdf,\x1a\xc5\xe7\x17*\x93Oz:>\x0e'

data_non_inlined = '\x00\x00\x00\x01\x00\x00\x00\x00\x00\x01D\x19' \
    '\x00\x07e\x12\x00\x00\x00\x00\x00\x00\x00\x00\xff\xff\xff\xff' \
    '\xff\xff\xff\xff\xd1\xf4\xbb\xb0\xbe\xfc\x13\xbd\x8c\xd3\x9d' \
    '\x0f\xcd\xd9;\x8c\x07\x8cJ/\x00\x00\x00\x00\x00\x00\x00\x00\x00' \
    '\x00\x00\x00\x00\x00\x00\x01D\x19\x00\x00\x00\x00\x00\xdf\x00' \
    '\x00\x01q\x00\x00\x00\x01\x00\x00\x00\x01\x00\x00\x00\x00\xff' \
    '\xff\xff\xff\xc1\x12\xb9\x04\x96\xa4Z1t\x91\xdfsJ\x90\xf0\x9bh' \
    '\x07l&\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00' \
    '\x00\x01D\xf8\x00\x00\x00\x00\x01\x1b\x00\x00\x01\xb8\x00\x00' \
    '\x00\x01\x00\x00\x00\x02\x00\x00\x00\x01\xff\xff\xff\xff\x02\n' \
    '\x0e\xc6&\xa1\x92\xae6\x0b\x02i\xfe-\xe5\xbao\x05\xd1\xe7\x00' \
    '\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01F' \
    '\x13\x00\x00\x00\x00\x01\xec\x00\x00\x03\x06\x00\x00\x00\x01' \
    '\x00\x00\x00\x03\x00\x00\x00\x02\xff\xff\xff\xff\x12\xcb\xeby1' \
    '\xb6\r\x98B\xcb\x07\xbd`\x8f\x92\xd9\xc4\x84\xbdK\x00\x00\x00' \
    '\x00\x00\x00\x00\x00\x00\x00\x00\x00'

def parse_index2(data, inline):
    index, chunkcache = parsers.parse_index2(data, inline)
    return list(index), chunkcache

def importparsers(hexversion):
    """Import mercurial.parsers with the given sys.hexversion."""
    # The file parsers.c inspects sys.hexversion to determine the version
    # of the currently-running Python interpreter, so we monkey-patch
    # sys.hexversion to simulate using different versions.
    code = ("import sys; sys.hexversion=%s; "
            "import mercurial.parsers" % hexversion)
    cmd = "python -c \"%s\"" % code
    # We need to do these tests inside a subprocess because parser.c's
    # version-checking code happens inside the module init function, and
    # when using reload() to reimport an extension module, "The init function
    # of extension modules is not called a second time"
    # (from http://docs.python.org/2/library/functions.html?#reload).
    p = subprocess.Popen(cmd, shell=True,
                         stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
    return p.communicate()  # returns stdout, stderr

def printhexfail(testnumber, hexversion, stdout, expected):
    try:
        hexstring = hex(hexversion)
    except TypeError:
        hexstring = None
    print("FAILED: version test #%s with Python %s and patched "
          "sys.hexversion %r (%r):\n Expected %s but got:\n-->'%s'\n" %
          (testnumber, sys.version_info, hexversion, hexstring, expected,
           stdout))

def testversionokay(testnumber, hexversion):
    stdout, stderr = importparsers(hexversion)
    if stdout:
        printhexfail(testnumber, hexversion, stdout, expected="no stdout")

def testversionfail(testnumber, hexversion):
    stdout, stderr = importparsers(hexversion)
    # We include versionerrortext to distinguish from other ImportErrors.
    errtext = "ImportError: %s" % parsers.versionerrortext
    if errtext not in stdout:
        printhexfail(testnumber, hexversion, stdout,
                     expected="stdout to contain %r" % errtext)

def makehex(major, minor, micro):
    return int("%x%02x%02x00" % (major, minor, micro), 16)

def runversiontests():
    """Check the version-detection logic when importing parsers."""
    info = sys.version_info
    major, minor, micro = info[0], info[1], info[2]
    # Test same major-minor versions.
    testversionokay(1, makehex(major, minor, micro))
    testversionokay(2, makehex(major, minor, micro + 1))
    # Test different major-minor versions.
    testversionfail(3, makehex(major + 1, minor, micro))
    testversionfail(4, makehex(major, minor + 1, micro))
    testversionfail(5, "'foo'")

def runtest() :
    # Only test the version-detection logic if it is present.
    try:
        parsers.versionerrortext
    except AttributeError:
        pass
    else:
        runversiontests()

    # Check that parse_index2() raises TypeError on bad arguments.
    try:
        parse_index2(0, True)
    except TypeError:
        pass
    else:
        print("Expected to get TypeError.")

   # Check parsers.parse_index2() on an index file against the original
   # Python implementation of parseindex, both with and without inlined data.

    py_res_1 = py_parseindex(data_inlined, True)
    c_res_1 = parse_index2(data_inlined, True)

    py_res_2 = py_parseindex(data_non_inlined, False)
    c_res_2 = parse_index2(data_non_inlined, False)

    if py_res_1 != c_res_1:
        print("Parse index result (with inlined data) differs!")

    if py_res_2 != c_res_2:
        print("Parse index result (no inlined data) differs!")

    ix = parsers.parse_index2(data_inlined, True)[0]
    for i, r in enumerate(ix):
        if r[7] == nullid:
            i = -1
        try:
            if ix[r[7]] != i:
                print('Reverse lookup inconsistent for %r'
                    % r[7].encode('hex'))
        except TypeError:
            # pure version doesn't support this
            break

    print("done")

runtest()