branchcache: skip entries that are topological heads in the on disk file
In the majority of cases, topological heads are also branch heads. We have
efficient way to get the topological heads and efficient way to retrieve
their branch information. So there is little value in putting them in the branch
cache file explicitly. On the contrary, writing them explicitly tend to create
very large cache file that are inefficient to read and update.
So the branch cache v3 format is no longer including them. This changeset focus
on the format aspect and have no focus on the performance aspect. We will cover
that later.
import unittest
import silenttestrunner
from mercurial import (
error,
scmutil,
)
class mockfile:
def __init__(self, name, fs):
self.name = name
self.fs = fs
def __enter__(self):
return self
def __exit__(self, *args, **kwargs):
pass
def write(self, text):
self.fs.contents[self.name] = text
def read(self):
return self.fs.contents[self.name]
class mockvfs:
def __init__(self):
self.contents = {}
def read(self, path):
return mockfile(path, self).read()
def readlines(self, path):
# lines need to contain the trailing '\n' to mock the real readlines
return [l for l in mockfile(path, self).read().splitlines(True)]
def __call__(self, path, mode, atomictemp):
return mockfile(path, self)
class testsimplekeyvaluefile(unittest.TestCase):
def setUp(self):
self.vfs = mockvfs()
def testbasicwritingiandreading(self):
dw = {b'key1': b'value1', b'Key2': b'value2'}
scmutil.simplekeyvaluefile(self.vfs, b'kvfile').write(dw)
self.assertEqual(
sorted(self.vfs.read(b'kvfile').split(b'\n')),
[b'', b'Key2=value2', b'key1=value1'],
)
dr = scmutil.simplekeyvaluefile(self.vfs, b'kvfile').read()
self.assertEqual(dr, dw)
if not getattr(unittest.TestCase, 'assertRaisesRegex', False):
# Python 3.7 deprecates the regex*p* version, but 2.7 lacks
# the regex version.
assertRaisesRegex = ( # camelcase-required
unittest.TestCase.assertRaisesRegexp
)
def testinvalidkeys(self):
d = {b'0key1': b'value1', b'Key2': b'value2'}
with self.assertRaisesRegex(
error.ProgrammingError, 'keys must start with a letter.*'
):
scmutil.simplekeyvaluefile(self.vfs, b'kvfile').write(d)
d = {b'key1@': b'value1', b'Key2': b'value2'}
with self.assertRaisesRegex(error.ProgrammingError, 'invalid key.*'):
scmutil.simplekeyvaluefile(self.vfs, b'kvfile').write(d)
def testinvalidvalues(self):
d = {b'key1': b'value1', b'Key2': b'value2\n'}
with self.assertRaisesRegex(error.ProgrammingError, 'invalid val.*'):
scmutil.simplekeyvaluefile(self.vfs, b'kvfile').write(d)
def testcorruptedfile(self):
self.vfs.contents[b'badfile'] = b'ababagalamaga\n'
with self.assertRaisesRegex(
error.CorruptedState, 'dictionary.*element.*'
):
scmutil.simplekeyvaluefile(self.vfs, b'badfile').read()
def testfirstline(self):
dw = {b'key1': b'value1'}
scmutil.simplekeyvaluefile(self.vfs, b'fl').write(dw, firstline=b'1.0')
self.assertEqual(self.vfs.read(b'fl'), b'1.0\nkey1=value1\n')
dr = scmutil.simplekeyvaluefile(self.vfs, b'fl').read(
firstlinenonkeyval=True
)
self.assertEqual(dr, {b'__firstline': b'1.0', b'key1': b'value1'})
if __name__ == "__main__":
silenttestrunner.main(__name__)