( )⚙ D11981 simplemerge: change _minimize() to minimize a single conflict

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Differential D11981

simplemerge: change _minimize() to minimize a single conflict
ClosedPublic

Authored by martinvonz on Jan 12 2022, 1:55 AM.

Details

Reviewers
Alphare
Group Reviewers
hg-reviewers
Commits
rHGc2537aec3bb6: simplemerge: change _minimize() to minimize a single conflict
rHGda04f362616d: simplemerge: change _minimize() to minimize a single conflict
Summary

_minimize() is weird in that it changes a_lines and b_lines but
leaves base_lines unchanged, which means they'll be
inconsistent. That was fine because the caller never used
base_lines. With the recent refactorings of this code, we can now
make this function cleaner by having it minimize a single conflict and
not care about base_lines.

This also makes the code simpler and makes the code for each
render_*() function more similar.

Diff Detail

Repository
rHG Mercurial
Lint
Automatic diff as part of commit; lint not applicable.
Unit
Automatic diff as part of commit; unit tests not applicable.

Revision Contents
Changeset List

PathPackages
Mmercurial/simplemerge.py (57 lines)

Diff 31675

mercurial/simplemerge.py

if len(m3.a) > 0: if len(m3.a) > 0:
if m3.a[0].endswith(b'\r\n'): if m3.a[0].endswith(b'\r\n'):
return b'\r\n' return b'\r\n'
elif m3.a[0].endswith(b'\r'): elif m3.a[0].endswith(b'\r'):
return b'\r' return b'\r'
return b'\n' return b'\n'
def _minimize(merge_groups): def _minimize(a_lines, b_lines):
"""Trim conflict regions of lines where A and B sides match. """Trim conflict regions of lines where A and B sides match.
Lines where both A and B have made the same changes at the beginning Lines where both A and B have made the same changes at the beginning
or the end of each merge region are eliminated from the conflict or the end of each merge region are eliminated from the conflict
region and are instead considered the same. region and are instead considered the same.
""" """
for what, lines in merge_groups:
if what != b"conflict":
yield what, lines
continue
base_lines, a_lines, b_lines = lines
alen = len(a_lines) alen = len(a_lines)
blen = len(b_lines) blen = len(b_lines)
# find matches at the front # find matches at the front
ii = 0 ii = 0
while ii < alen and ii < blen and a_lines[ii] == b_lines[ii]: while ii < alen and ii < blen and a_lines[ii] == b_lines[ii]:
ii += 1 ii += 1
startmatches = ii startmatches = ii
# find matches at the end # find matches at the end
ii = 0 ii = 0
while ii < alen and ii < blen and a_lines[-ii - 1] == b_lines[-ii - 1]: while ii < alen and ii < blen and a_lines[-ii - 1] == b_lines[-ii - 1]:
ii += 1 ii += 1
endmatches = ii endmatches = ii
if startmatches > 0: lines_before = a_lines[:startmatches]
yield b'same', a_lines[:startmatches] new_a_lines = a_lines[startmatches : alen - endmatches]
new_b_lines = b_lines[startmatches : blen - endmatches]
yield ( lines_after = a_lines[alen - endmatches :]
b'conflict', return lines_before, new_a_lines, new_b_lines, lines_after
(
base_lines,
a_lines[startmatches : alen - endmatches],
b_lines[startmatches : blen - endmatches],
),
)
if endmatches > 0:
yield b'same', a_lines[alen - endmatches :]
def render_minimized( def render_minimized(
m3, m3,
name_a=None, name_a=None,
name_b=None, name_b=None,
start_marker=b'<<<<<<<', start_marker=b'<<<<<<<',
mid_marker=b'=======', mid_marker=b'=======',
end_marker=b'>>>>>>>', end_marker=b'>>>>>>>',
): ):
"""Return merge in cvs-like form.""" """Return merge in cvs-like form."""
newline = _detect_newline(m3) newline = _detect_newline(m3)
conflicts = False conflicts = False
if name_a: if name_a:
start_marker = start_marker + b' ' + name_a start_marker = start_marker + b' ' + name_a
if name_b: if name_b:
end_marker = end_marker + b' ' + name_b end_marker = end_marker + b' ' + name_b
merge_groups = m3.merge_groups() merge_groups = m3.merge_groups()
merge_groups = _minimize(merge_groups)
lines = [] lines = []
for what, group_lines in merge_groups: for what, group_lines in merge_groups:
if what == b'conflict': if what == b'conflict':
base_lines, a_lines, b_lines = group_lines
conflicts = True conflicts = True
base_lines, a_lines, b_lines = group_lines
minimized = _minimize(a_lines, b_lines)
lines_before, a_lines, b_lines, lines_after = minimized
lines.extend(lines_before)
lines.append(start_marker + newline) lines.append(start_marker + newline)
lines.extend(a_lines) lines.extend(a_lines)
lines.append(mid_marker + newline) lines.append(mid_marker + newline)
lines.extend(b_lines) lines.extend(b_lines)
lines.append(end_marker + newline) lines.append(end_marker + newline)
lines.extend(lines_after)
else: else:
lines.extend(group_lines) lines.extend(group_lines)
return lines, conflicts return lines, conflicts
def render_merge3(m3, name_a, name_b, name_base): def render_merge3(m3, name_a, name_b, name_base):
"""Render conflicts as 3-way conflict markers.""" """Render conflicts as 3-way conflict markers."""
newline = _detect_newline(m3) newline = _detect_newline(m3)