branchcache: add a "pure topological head" fast path
In a narrow but actually quick common case, all topological heads are all on
the same branch and all open. In this case, computing the branch map is very
simple. We can quickly detect situation where this situation will not change.
So we update the V3 format to be able to express this situation and upgrade the
update code to detect we remains in that mode.
The branch cache is populated with the actual value when the branch map is
accessed, but the update_disk method can do the update without needing to
populate it.
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__)