Mercurial > hg
view tests/test-bdiff.py @ 31063:18fb3cf572b4 stable
worker: ignore meaningless exit status indication returned by os.waitpid()
Before this patch, worker implementation assumes that os.waitpid()
with os.WNOHANG returns '(0, 0)' for still running child process. This
is explicitly specified as below in Python API document.
os.WNOHANG
The option for waitpid() to return immediately if no child
process status is available immediately. The function returns
(0, 0) in this case.
On the other hand, POSIX specification doesn't define the "stat_loc"
value returned by waitpid() with WNOHANG for such child process.
http://pubs.opengroup.org/onlinepubs/9699919799/functions/waitpid.html
CPython implementation for os.waitpid() on POSIX doesn't take any care
of this gap, and this may cause unexpected "exit status indication"
even on POSIX conformance platform.
For example, os.waitpid() with os.WNOHANG returns non-zero "exit
status indication" on FreeBSD. This implies os.kill() with own pid or
sys.exit() with non-zero exit code, even if no child process fails.
To ignore meaningless exit status indication returned by os.waitpid(),
this patch skips subsequent steps forcibly, if os.waitpid() returns 0
as pid.
This patch also arranges examination of 'p' value for readability.
FYI, there are some issues below about this behavior reported for
CPython.
https://bugs.python.org/issue21791
https://bugs.python.org/issue27808
author | FUJIWARA Katsunori <foozy@lares.dti.ne.jp> |
---|---|
date | Sat, 25 Feb 2017 01:07:52 +0900 |
parents | 99bd5479d58b |
children | f2ad0d804700 |
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from __future__ import absolute_import, print_function import collections import struct import unittest import silenttestrunner from mercurial import ( bdiff, mpatch, ) class diffreplace( collections.namedtuple('diffreplace', 'start end from_ to')): def __repr__(self): return 'diffreplace(%r, %r, %r, %r)' % self class BdiffTests(unittest.TestCase): def assert_bdiff_applies(self, a, b): d = bdiff.bdiff(a, b) c = a if d: c = mpatch.patches(a, [d]) self.assertEqual( c, b, ("bad diff+patch result from\n %r to\n " "%r: \nbdiff: %r\npatched: %r" % (a, b, d, c[:200]))) def assert_bdiff(self, a, b): self.assert_bdiff_applies(a, b) self.assert_bdiff_applies(b, a) def test_bdiff_basic(self): cases = [ ("a\nc\n\n\n\n", "a\nb\n\n\n"), ("a\nb\nc\n", "a\nc\n"), ("", ""), ("a\nb\nc", "a\nb\nc"), ("a\nb\nc\nd\n", "a\nd\n"), ("a\nb\nc\nd\n", "a\nc\ne\n"), ("a\nb\nc\n", "a\nc\n"), ("a\n", "c\na\nb\n"), ("a\n", ""), ("a\n", "b\nc\n"), ("a\n", "c\na\n"), ("", "adjfkjdjksdhfksj"), ("", "ab"), ("", "abc"), ("a", "a"), ("ab", "ab"), ("abc", "abc"), ("a\n", "a\n"), ("a\nb", "a\nb"), ] for a, b in cases: self.assert_bdiff(a, b) def showdiff(self, a, b): bin = bdiff.bdiff(a, b) pos = 0 q = 0 actions = [] while pos < len(bin): p1, p2, l = struct.unpack(">lll", bin[pos:pos + 12]) pos += 12 if p1: actions.append(a[q:p1]) actions.append(diffreplace(p1, p2, a[p1:p2], bin[pos:pos + l])) pos += l q = p2 if q < len(a): actions.append(a[q:]) return actions def test_issue1295(self): cases = [ ("x\n\nx\n\nx\n\nx\n\nz\n", "x\n\nx\n\ny\n\nx\n\nx\n\nz\n", ['x\n\nx\n\n', diffreplace(6, 6, '', 'y\n\n'), 'x\n\nx\n\nz\n']), ("x\n\nx\n\nx\n\nx\n\nz\n", "x\n\nx\n\ny\n\nx\n\ny\n\nx\n\nz\n", ['x\n\nx\n\n', diffreplace(6, 6, '', 'y\n\n'), 'x\n\n', diffreplace(9, 9, '', 'y\n\n'), 'x\n\nz\n']), ] for old, new, want in cases: self.assertEqual(self.showdiff(old, new), want) def test_issue1295_varies_on_pure(self): # we should pick up abbbc. rather than bc.de as the longest match got = self.showdiff("a\nb\nb\nb\nc\n.\nd\ne\n.\nf\n", "a\nb\nb\na\nb\nb\nb\nc\n.\nb\nc\n.\nd\ne\nf\n") want_c = ['a\nb\nb\n', diffreplace(6, 6, '', 'a\nb\nb\nb\nc\n.\n'), 'b\nc\n.\nd\ne\n', diffreplace(16, 18, '.\n', ''), 'f\n'] want_pure = [diffreplace(0, 0, '', 'a\nb\nb\n'), 'a\nb\nb\nb\nc\n.\n', diffreplace(12, 12, '', 'b\nc\n.\n'), 'd\ne\n', diffreplace(16, 18, '.\n', ''), 'f\n'] self.assert_(got in (want_c, want_pure), 'got: %r, wanted either %r or %r' % ( got, want_c, want_pure)) def test_fixws(self): cases = [ (" \ta\r b\t\n", "ab\n", 1), (" \ta\r b\t\n", " a b\n", 0), ("", "", 1), ("", "", 0), ] for a, b, allws in cases: c = bdiff.fixws(a, allws) self.assertEqual( c, b, 'fixws(%r) want %r got %r (allws=%r)' % (a, b, c, allws)) def test_nice_diff_for_trivial_change(self): self.assertEqual(self.showdiff( ''.join('<%s\n-\n' % i for i in range(5)), ''.join('>%s\n-\n' % i for i in range(5))), [diffreplace(0, 3, '<0\n', '>0\n'), '-\n', diffreplace(5, 8, '<1\n', '>1\n'), '-\n', diffreplace(10, 13, '<2\n', '>2\n'), '-\n', diffreplace(15, 18, '<3\n', '>3\n'), '-\n', diffreplace(20, 23, '<4\n', '>4\n'), '-\n']) def test_prefer_appending(self): # 1 line to 3 lines self.assertEqual(self.showdiff('a\n', 'a\n' * 3), ['a\n', diffreplace(2, 2, '', 'a\na\n')]) # 1 line to 5 lines self.assertEqual(self.showdiff('a\n', 'a\n' * 5), ['a\n', diffreplace(2, 2, '', 'a\na\na\na\n')]) def test_prefer_removing_trailing(self): # 3 lines to 1 line self.assertEqual(self.showdiff('a\n' * 3, 'a\n'), ['a\n', diffreplace(2, 6, 'a\na\n', '')]) # 5 lines to 1 line self.assertEqual(self.showdiff('a\n' * 5, 'a\n'), ['a\n', diffreplace(2, 10, 'a\na\na\na\n', '')]) if __name__ == '__main__': silenttestrunner.main(__name__)