log: add -L/--line-range option to follow file history by line range
We add an experimental -L/--line-range option to 'hg log' taking file patterns
along with a line range using the (new) FILE,FROMLINE-TOLINE syntax where FILE
may be a pattern (matching exactly one file). The resulting history is similar
to what the "followlines" revset except that, if --patch is specified,
only diff hunks within specified line range are shown.
Basically, this brings the CLI on par with what currently only exists in hgweb
through line selection in "file" and "annotate" views resulting in a file log
with filtered patch to only display followed line range.
The option may be specified multiple times and can be combined with --rev and
regular file patterns to further restrict revisions. Usage of this option
requires --follow; revisions are shown in descending order and renames are
followed. Only the --graph option is currently not supported.
The UI is the result of a consensus from review feedback at:
https://www.mercurial-scm.org/pipermail/mercurial-devel/2017-October/106749.html
The implementation spreads between commands.log() and cmdutil module.
In commands.log(), the main loop may now use a "hunksfilter" factory (similar
to "filematcher") that, for a given "rev", produces a filtering function
for diff hunks for a given file context object.
The logic to build revisions from -L/--line-range options lives in
cmdutil.getloglinerangerevs() which produces "revs", "filematcher" and
"hunksfilter" information. Revisions obtained by following files' line range
are filtered if they do not match the revset specified by --rev option. If
regular FILE arguments are passed along with -L options, both filematchers are
combined into a new matcher.
.. feature::
Add an experimental -L/--line-range FILE,FROMLINE-TOLINE option to 'hg log'
command to follow the history of files by line range. In combination with
-p/--patch option, only diff hunks within specified line range will be
displayed. Feedback, especially on UX aspects, is welcome.
from __future__ import absolute_import, print_function
import collections
import struct
import unittest
from mercurial import (
mdiff,
)
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 = mdiff.textdiff(a, b)
c = a
if d:
c = mdiff.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 = mdiff.textdiff(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 = mdiff.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__':
import silenttestrunner
silenttestrunner.main(__name__)