dirstate-tree: Add tree traversal/iteration
Like Python’s, Rust’s iterators are "external" in that they are driven
by a caller who calls a `next` method. This is as opposed to "internal"
iterators who drive themselves and call a callback for each item.
Writing an internal iterator traversing a tree is easy with recursion,
but internal iterators cannot rely on the call stack in that way,
they must save in an explicit object all state that they need to be
preserved across two `next` calls.
This algorithm uses a `Vec` as a stack that contains what would be
local variables on the call stack if we could use recursion.
Differential Revision: https://phab.mercurial-scm.org/D10370
"""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 os
import struct
import subprocess
import sys
import unittest
from mercurial.node import (
bin,
hex,
nullrev,
sha1nodeconstants,
)
from mercurial import (
policy,
pycompat,
)
parsers = policy.importmod('parsers')
# original python implementation
def gettype(q):
return int(q & 0xFFFF)
def offset_type(offset, type):
return int(int(offset) << 16 | type)
indexformatng = ">Qiiiiii20s12x"
def py_parseindex(data, inline):
s = 64
cache = None
index = []
nodemap = {sha1nodeconstants.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)
return index, cache
data_inlined = (
b'\x00\x01\x00\x01\x00\x00\x00\x00\x00\x00\x01\x8c'
b'\x00\x00\x04\x07\x00\x00\x00\x00\x00\x00\x15\x15\xff\xff\xff'
b'\xff\xff\xff\xff\xff\xebG\x97\xb7\x1fB\x04\xcf\x13V\x81\tw\x1b'
b'w\xdduR\xda\xc6\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
b'x\x9c\x9d\x93?O\xc30\x10\xc5\xf7|\x8a\xdb\x9a\xa8m\x06\xd8*\x95'
b'\x81B\xa1\xa2\xa2R\xcb\x86Pd\x9a\x0b5$vd_\x04\xfd\xf6\x9c\xff@'
b'\x11!\x0b\xd9\xec\xf7\xbbw\xe7gG6\xad6\x04\xdaN\xc0\x92\xa0$)'
b'\xb1\x82\xa2\xd1%\x16\xa4\x8b7\xa9\xca\xd4-\xb2Y\x02\xfc\xc9'
b'\xcaS\xf9\xaeX\xed\xb6\xd77Q\x02\x83\xd4\x19\xf5--Y\xea\xe1W'
b'\xab\xed\x10\xceR\x0f_\xdf\xdf\r\xe1,\xf5\xf0\xcb\xf5 \xceR\x0f'
b'_\xdc\x0e\x0e\xc3R\x0f_\xae\x96\x9b!\x9e\xa5\x1e\xbf\xdb,\x06'
b'\xc7q\x9a/\x88\x82\xc3B\xea\xb5\xb4TJ\x93\xb6\x82\x0e\xe16\xe6'
b'KQ\xdb\xaf\xecG\xa3\xd1 \x01\xd3\x0b_^\xe8\xaa\xa0\xae\xad\xd1'
b'&\xbef\x1bz\x08\xb0|\xc9Xz\x06\xf6Z\x91\x90J\xaa\x17\x90\xaa'
b'\xd2\xa6\x11$5C\xcf\xba#\xa0\x03\x02*2\x92-\xfc\xb1\x94\xdf\xe2'
b'\xae\xb8\'m\x8ey0^\x85\xd3\x82\xb4\xf0`:\x9c\x00\x8a\xfd\x01'
b'\xb0\xc6\x86\x8b\xdd\xae\x80\xf3\xa9\x9fd\x16\n\x00R%\x1a\x06'
b'\xe9\xd8b\x98\x1d\xf4\xf3+\x9bf\x01\xd8p\x1b\xf3.\xed\x9f^g\xc3'
b'^\xd9W81T\xdb\xd5\x04sx|\xf2\xeb\xd6`%?x\xed"\x831\xbf\xf3\xdc'
b'b\xeb%gaY\xe1\xad\x9f\xb9f\'1w\xa9\xa5a\x83s\x82J\xb98\xbc4\x8b'
b'\x83\x00\x9f$z\xb8#\xa5\xb1\xdf\x98\xd9\xec\x1b\x89O\xe3Ts\x9a4'
b'\x17m\x8b\xfc\x8f\xa5\x95\x9a\xfc\xfa\xed,\xe5|\xa1\xfe\x15\xb9'
b'\xbc\xb2\x93\x1f\xf2\x95\xff\xdf,\x1a\xc5\xe7\x17*\x93Oz:>\x0e'
)
data_non_inlined = (
b'\x00\x00\x00\x01\x00\x00\x00\x00\x00\x01D\x19'
b'\x00\x07e\x12\x00\x00\x00\x00\x00\x00\x00\x00\xff\xff\xff\xff'
b'\xff\xff\xff\xff\xd1\xf4\xbb\xb0\xbe\xfc\x13\xbd\x8c\xd3\x9d'
b'\x0f\xcd\xd9;\x8c\x07\x8cJ/\x00\x00\x00\x00\x00\x00\x00\x00\x00'
b'\x00\x00\x00\x00\x00\x00\x01D\x19\x00\x00\x00\x00\x00\xdf\x00'
b'\x00\x01q\x00\x00\x00\x01\x00\x00\x00\x01\x00\x00\x00\x00\xff'
b'\xff\xff\xff\xc1\x12\xb9\x04\x96\xa4Z1t\x91\xdfsJ\x90\xf0\x9bh'
b'\x07l&\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00'
b'\x00\x01D\xf8\x00\x00\x00\x00\x01\x1b\x00\x00\x01\xb8\x00\x00'
b'\x00\x01\x00\x00\x00\x02\x00\x00\x00\x01\xff\xff\xff\xff\x02\n'
b'\x0e\xc6&\xa1\x92\xae6\x0b\x02i\xfe-\xe5\xbao\x05\xd1\xe7\x00'
b'\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01F'
b'\x13\x00\x00\x00\x00\x01\xec\x00\x00\x03\x06\x00\x00\x00\x01'
b'\x00\x00\x00\x03\x00\x00\x00\x02\xff\xff\xff\xff\x12\xcb\xeby1'
b'\xb6\r\x98B\xcb\x07\xbd`\x8f\x92\xd9\xc4\x84\xbdK\x00\x00\x00'
b'\x00\x00\x00\x00\x00\x00\x00\x00\x00'
)
def parse_index2(data, inline, revlogv2=False):
index, chunkcache = parsers.parse_index2(data, inline, revlogv2=revlogv2)
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.cext.parsers" % hexversion
)
cmd = "\"%s\" -c \"%s\"" % (os.environ['PYTHON'], 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 hexfailmsg(testnumber, hexversion, stdout, expected):
try:
hexstring = hex(hexversion)
except TypeError:
hexstring = None
return (
"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 makehex(major, minor, micro):
return int("%x%02x%02x00" % (major, minor, micro), 16)
class parseindex2tests(unittest.TestCase):
def assertversionokay(self, testnumber, hexversion):
stdout, stderr = importparsers(hexversion)
self.assertFalse(
stdout, hexfailmsg(testnumber, hexversion, stdout, 'no stdout')
)
def assertversionfail(self, testnumber, hexversion):
stdout, stderr = importparsers(hexversion)
# We include versionerrortext to distinguish from other ImportErrors.
errtext = b"ImportError: %s" % pycompat.sysbytes(
parsers.versionerrortext
)
self.assertIn(
errtext,
stdout,
hexfailmsg(
testnumber,
hexversion,
stdout,
expected="stdout to contain %r" % errtext,
),
)
def testversiondetection(self):
"""Check the version-detection logic when importing parsers."""
# Only test the version-detection logic if it is present.
try:
parsers.versionerrortext
except AttributeError:
return
info = sys.version_info
major, minor, micro = info[0], info[1], info[2]
# Test same major-minor versions.
self.assertversionokay(1, makehex(major, minor, micro))
self.assertversionokay(2, makehex(major, minor, micro + 1))
# Test different major-minor versions.
self.assertversionfail(3, makehex(major + 1, minor, micro))
self.assertversionfail(4, makehex(major, minor + 1, micro))
self.assertversionfail(5, "'foo'")
def testbadargs(self):
# Check that parse_index2() raises TypeError on bad arguments.
with self.assertRaises(TypeError):
parse_index2(0, True)
def testparseindexfile(self):
# Check parsers.parse_index2() on an index file against the
# original Python implementation of parseindex, both with and
# without inlined data.
want = py_parseindex(data_inlined, True)
got = parse_index2(data_inlined, True)
self.assertEqual(want, got) # inline data
want = py_parseindex(data_non_inlined, False)
got = parse_index2(data_non_inlined, False)
self.assertEqual(want, got) # no inline data
ix = parsers.parse_index2(data_inlined, True)[0]
for i, r in enumerate(ix):
if r[7] == sha1nodeconstants.nullid:
i = -1
try:
self.assertEqual(
ix[r[7]],
i,
'Reverse lookup inconsistent for %r' % hex(r[7]),
)
except TypeError:
# pure version doesn't support this
break
def testminusone(self):
want = (0, 0, 0, -1, -1, -1, -1, sha1nodeconstants.nullid)
index, junk = parsers.parse_index2(data_inlined, True)
got = index[-1]
self.assertEqual(want, got) # inline data
index, junk = parsers.parse_index2(data_non_inlined, False)
got = index[-1]
self.assertEqual(want, got) # no inline data
def testdelitemwithoutnodetree(self):
index, _junk = parsers.parse_index2(data_non_inlined, False)
def hexrev(rev):
if rev == nullrev:
return b'\xff\xff\xff\xff'
else:
return bin('%08x' % rev)
def appendrev(p1, p2=nullrev):
# node won't matter for this test, let's just make sure
# they don't collide. Other data don't matter either.
node = hexrev(p1) + hexrev(p2) + b'.' * 12
index.append((0, 0, 12, 1, 34, p1, p2, node))
appendrev(4)
appendrev(5)
appendrev(6)
self.assertEqual(len(index), 7)
del index[1:-1]
# assertions that failed before correction
self.assertEqual(len(index), 1) # was 4
headrevs = getattr(index, 'headrevs', None)
if headrevs is not None: # not implemented in pure
self.assertEqual(index.headrevs(), [0]) # gave ValueError
if __name__ == '__main__':
import silenttestrunner
silenttestrunner.main(__name__)