view tests/test-parseindex2.py @ 31793:69d8fcf20014

help: document bundle specifications

I softly formalized the concept of a "bundle specification" a while
ago when I was working on clone bundles and stream clone bundles and
wanted a more robust way to define what exactly is in a bundle file.

The concept has existed for a while. Since it is part of the clone
bundles feature and exposed to the user via the "-t" argument to
`hg bundle`, it is something we need to support for the long haul.

After the 4.1 release, I heard a few people comment that they didn't
realize you could generate zstd bundles with `hg bundle`. I'm
partially to blame for not documenting it in bundle's docstring.

Additionally, I added a hacky, experimental feature for controlling
the compression level of bundles in 76104a4899ad. As the commit
message says, I went with a quick and dirty solution out of time
constraints. Furthermore, I wanted to eventually store this
configuration in the "bundlespec" so it could be made more flexible.

Given:

a) bundlespecs are here to stay
b) we don't have great documentation over what they are, despite being
   a user-facing feature
c) the list of available compression engines and their behavior isn't
   exposed
d) we need an extensible place to modify behavior of compression
   engines

I want to move forward with formalizing bundlespecs as a user-facing
feature. This commit does that by introducing a "bundlespec" help
page. Leaning on the just-added compression engine documentation
and API, the topic also conveniently lists available compression
engines and details about them. This makes features like zstd
bundle compression more discoverable. e.g. you can now
`hg help -k zstd` and it lists the "bundlespec" topic.

"""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()