procutil: make stream detection in make_line_buffered more correct and strict
In make_line_buffered(), we don’t want to wrap the stream if we know that lines
get flushed to the underlying raw stream already.
Previously, the heuristic was too optimistic. It assumed that any stream which
is not an instance of io.BufferedIOBase doesn’t need wrapping. However, there
are buffered streams that aren’t instances of io.BufferedIOBase, like
Mercurial’s own winstdout.
The new logic is different in two ways:
First, only for the check, if unwraps any combination of WriteAllWrapper and
winstdout.
Second, it skips wrapping the stream only if it is an instance of io.RawIOBase
(or already wrapped). If it is an instance of io.BufferedIOBase, it gets
wrapped. In any other case, the function raises an exception. This ensures
that, if an unknown stream is passed or we add another wrapper in the future,
we don’t wrap the stream if it’s already line buffered or not wrap the stream
if it’s not line buffered. In fact, this was already helpful during development
of this change. Without it, I possibly would have forgot that WriteAllWrapper
needs to be ignored for the check, leading to unnecessary wrapping if stdout is
unbuffered.
The alternative would have been to always wrap unknown streams. However, I
don’t think that anyone would benefit from being less strict. We can expect
streams from the standard library to be subclassing either io.RawIOBase or
io.BufferedIOBase, so running Mercurial in the standard way should not regress
by this change. Py2exe might replace sys.stdout and sys.stderr, but that
currently breaks Mercurial anyway and also these streams don’t claim to be
interactive, so this function is not called for them.
#!/usr/bin/env python
import hashlib
import os
import random
import shutil
import stat
import struct
import sys
import tempfile
import unittest
import silenttestrunner
from mercurial.node import sha1nodeconstants
from mercurial import (
pycompat,
ui as uimod,
)
# Load the local remotefilelog, not the system one
sys.path[0:0] = [os.path.join(os.path.dirname(__file__), '..')]
from hgext.remotefilelog import (
basepack,
historypack,
)
class histpacktests(unittest.TestCase):
def setUp(self):
self.tempdirs = []
def tearDown(self):
for d in self.tempdirs:
shutil.rmtree(d)
def makeTempDir(self):
tempdir = tempfile.mkdtemp()
self.tempdirs.append(tempdir)
return pycompat.fsencode(tempdir)
def getHash(self, content):
return hashlib.sha1(content).digest()
def getFakeHash(self):
return b''.join(
pycompat.bytechr(random.randint(0, 255)) for _ in range(20)
)
def createPack(self, revisions=None):
"""Creates and returns a historypack containing the specified revisions.
`revisions` is a list of tuples, where each tuple contains a filanem,
node, p1node, p2node, and linknode.
"""
if revisions is None:
revisions = [
(
b"filename",
self.getFakeHash(),
sha1nodeconstants.nullid,
sha1nodeconstants.nullid,
self.getFakeHash(),
None,
)
]
packdir = pycompat.fsencode(self.makeTempDir())
packer = historypack.mutablehistorypack(uimod.ui(), packdir, version=2)
for filename, node, p1, p2, linknode, copyfrom in revisions:
packer.add(filename, node, p1, p2, linknode, copyfrom)
path = packer.close()
return historypack.historypack(path)
def testAddSingle(self):
"""Test putting a single entry into a pack and reading it out."""
filename = b"foo"
node = self.getFakeHash()
p1 = self.getFakeHash()
p2 = self.getFakeHash()
linknode = self.getFakeHash()
revisions = [(filename, node, p1, p2, linknode, None)]
pack = self.createPack(revisions)
actual = pack.getancestors(filename, node)[node]
self.assertEqual(p1, actual[0])
self.assertEqual(p2, actual[1])
self.assertEqual(linknode, actual[2])
def testAddMultiple(self):
"""Test putting multiple unrelated revisions into a pack and reading
them out.
"""
revisions = []
for i in range(10):
filename = b"foo-%d" % i
node = self.getFakeHash()
p1 = self.getFakeHash()
p2 = self.getFakeHash()
linknode = self.getFakeHash()
revisions.append((filename, node, p1, p2, linknode, None))
pack = self.createPack(revisions)
for filename, node, p1, p2, linknode, copyfrom in revisions:
actual = pack.getancestors(filename, node)[node]
self.assertEqual(p1, actual[0])
self.assertEqual(p2, actual[1])
self.assertEqual(linknode, actual[2])
self.assertEqual(copyfrom, actual[3])
def testAddAncestorChain(self):
"""Test putting multiple revisions in into a pack and read the ancestor
chain.
"""
revisions = []
filename = b"foo"
lastnode = sha1nodeconstants.nullid
for i in range(10):
node = self.getFakeHash()
revisions.append(
(
filename,
node,
lastnode,
sha1nodeconstants.nullid,
sha1nodeconstants.nullid,
None,
)
)
lastnode = node
# revisions must be added in topological order, newest first
revisions = list(reversed(revisions))
pack = self.createPack(revisions)
# Test that the chain has all the entries
ancestors = pack.getancestors(revisions[0][0], revisions[0][1])
for filename, node, p1, p2, linknode, copyfrom in revisions:
ap1, ap2, alinknode, acopyfrom = ancestors[node]
self.assertEqual(ap1, p1)
self.assertEqual(ap2, p2)
self.assertEqual(alinknode, linknode)
self.assertEqual(acopyfrom, copyfrom)
def testPackMany(self):
"""Pack many related and unrelated ancestors."""
# Build a random pack file
allentries = {}
ancestorcounts = {}
revisions = []
random.seed(0)
for i in range(100):
filename = b"filename-%d" % i
entries = []
p2 = sha1nodeconstants.nullid
linknode = sha1nodeconstants.nullid
for j in range(random.randint(1, 100)):
node = self.getFakeHash()
p1 = sha1nodeconstants.nullid
if len(entries) > 0:
p1 = entries[random.randint(0, len(entries) - 1)]
entries.append(node)
revisions.append((filename, node, p1, p2, linknode, None))
allentries[(filename, node)] = (p1, p2, linknode)
if p1 == sha1nodeconstants.nullid:
ancestorcounts[(filename, node)] = 1
else:
newcount = ancestorcounts[(filename, p1)] + 1
ancestorcounts[(filename, node)] = newcount
# Must add file entries in reverse topological order
revisions = list(reversed(revisions))
pack = self.createPack(revisions)
# Verify the pack contents
for (filename, node) in allentries:
ancestors = pack.getancestors(filename, node)
self.assertEqual(ancestorcounts[(filename, node)], len(ancestors))
for anode, (ap1, ap2, alinknode, copyfrom) in ancestors.items():
ep1, ep2, elinknode = allentries[(filename, anode)]
self.assertEqual(ap1, ep1)
self.assertEqual(ap2, ep2)
self.assertEqual(alinknode, elinknode)
self.assertEqual(copyfrom, None)
def testGetNodeInfo(self):
revisions = []
filename = b"foo"
lastnode = sha1nodeconstants.nullid
for i in range(10):
node = self.getFakeHash()
revisions.append(
(
filename,
node,
lastnode,
sha1nodeconstants.nullid,
sha1nodeconstants.nullid,
None,
)
)
lastnode = node
pack = self.createPack(revisions)
# Test that getnodeinfo returns the expected results
for filename, node, p1, p2, linknode, copyfrom in revisions:
ap1, ap2, alinknode, acopyfrom = pack.getnodeinfo(filename, node)
self.assertEqual(ap1, p1)
self.assertEqual(ap2, p2)
self.assertEqual(alinknode, linknode)
self.assertEqual(acopyfrom, copyfrom)
def testGetMissing(self):
"""Test the getmissing() api."""
revisions = []
filename = b"foo"
for i in range(10):
node = self.getFakeHash()
p1 = self.getFakeHash()
p2 = self.getFakeHash()
linknode = self.getFakeHash()
revisions.append((filename, node, p1, p2, linknode, None))
pack = self.createPack(revisions)
missing = pack.getmissing([(filename, revisions[0][1])])
self.assertFalse(missing)
missing = pack.getmissing(
[(filename, revisions[0][1]), (filename, revisions[1][1])]
)
self.assertFalse(missing)
fakenode = self.getFakeHash()
missing = pack.getmissing(
[(filename, revisions[0][1]), (filename, fakenode)]
)
self.assertEqual(missing, [(filename, fakenode)])
# Test getmissing on a non-existant filename
missing = pack.getmissing([(b"bar", fakenode)])
self.assertEqual(missing, [(b"bar", fakenode)])
def testAddThrows(self):
pack = self.createPack()
try:
pack.add(
b'filename',
sha1nodeconstants.nullid,
sha1nodeconstants.nullid,
sha1nodeconstants.nullid,
sha1nodeconstants.nullid,
None,
)
self.assertTrue(False, "historypack.add should throw")
except RuntimeError:
pass
def testBadVersionThrows(self):
pack = self.createPack()
path = pack.path + b'.histpack'
with open(path, 'rb') as f:
raw = f.read()
raw = struct.pack('!B', 255) + raw[1:]
os.chmod(path, os.stat(path).st_mode | stat.S_IWRITE)
with open(path, 'wb+') as f:
f.write(raw)
try:
historypack.historypack(pack.path)
self.assertTrue(False, "bad version number should have thrown")
except RuntimeError:
pass
def testLargePack(self):
"""Test creating and reading from a large pack with over X entries.
This causes it to use a 2^16 fanout table instead."""
total = basepack.SMALLFANOUTCUTOFF + 1
revisions = []
for i in range(total):
filename = b"foo-%d" % i
node = self.getFakeHash()
p1 = self.getFakeHash()
p2 = self.getFakeHash()
linknode = self.getFakeHash()
revisions.append((filename, node, p1, p2, linknode, None))
pack = self.createPack(revisions)
self.assertEqual(pack.params.fanoutprefix, basepack.LARGEFANOUTPREFIX)
for filename, node, p1, p2, linknode, copyfrom in revisions:
actual = pack.getancestors(filename, node)[node]
self.assertEqual(p1, actual[0])
self.assertEqual(p2, actual[1])
self.assertEqual(linknode, actual[2])
self.assertEqual(copyfrom, actual[3])
# TODO:
# histpack store:
# - repack two packs into one
if __name__ == '__main__':
if pycompat.iswindows:
sys.exit(80) # Skip on Windows
silenttestrunner.main(__name__)