def test_from_diff_multiple(self):
self.assertEqual(
matcher.MatchInfo.from_diff('metavar', 'a\nb\nc\n', '1\nb\n3\n'),
matcher.MatchInfo(
match.Match(),
bindings={
'metavar.0':
matcher.BoundValue(
match.SpanMatch(
string='a\n',
span=(0, 2),
)),
'metavar.1':
matcher.BoundValue(
match.SpanMatch(
string='c\n',
span=(4, 6),
)),
},
replacements={
'metavar.0': formatting.LiteralTemplate('1\n'),
'metavar.1': formatting.LiteralTemplate('3\n'),
},
),
)
def from_diff(
cls,
metavariable_prefix: str,
before: str,
after: str,
match=_match.Match(),
) -> 'MatchInfo':
"""Returns a minimized ``MatchInfo`` for the diff of before/after.
Args:
metavariable_prefix: the prefix for the named bindings/replacements.
before: the entire file, before.
after: the entire file, after.
match: The match for the MatchInfo.
Returns:
A minimized ``MatchInfo`` for that diff.
"""
diffs = difflib.Differ().compare(
before.splitlines(True),
after.splitlines(True),
)
# change the diffs to always end with an "unchanged" line, triggering
# an append to `replacements`.
diffs = itertools.chain(diffs, [' '])
start_offset = 0
end_offset = 0
replacement = []
replacements = []
for line in diffs:
prefix = line[:2]
line = line[2:]
if prefix == ' ':
if replacement or start_offset != end_offset:
replacements.append(
(start_offset, end_offset, replacement))
replacement = []
end_offset += len(line)
start_offset = end_offset
elif prefix == '+ ':
replacement.append(line)
elif prefix == '- ':
end_offset += len(line)
elif prefix == '? ':
pass
else:
raise AssertionError(f'Unknown diff prefix: {prefix!r}')
assert not replacement
match_bindings = {}
match_replacements = {}
for i, (start, end, added_strings) in enumerate(replacements):
metavar = f'{metavariable_prefix}.{i}'
match_bindings[metavar] = BoundValue(
_match.SpanMatch.from_text(before, (start, end)))
match_replacements[metavar] = formatting.LiteralTemplate(
''.join(added_strings))
return cls(match, match_bindings, match_replacements)
def matcher_with_meta(self):
if isinstance(self._replacement, formatting.Template):
replacements = {search.ROOT_LABEL: self._replacement}
else:
replacements = self._replacement
if self._message is not None:
replacements[search.MESSAGE_LABEL] = formatting.LiteralTemplate(
self._message)
if self._url is not None:
replacements[search.URL_LABEL] = formatting.LiteralTemplate(
self._url)
if self._category is not None:
replacements[search.CATEGORY_LABEL] = formatting.LiteralTemplate(
self._category)
if self._significant:
replacements[
search.SIGNIFICANT_LABEL] = formatting.LiteralTemplate(
'HACK_TRUE')
return base_matchers.WithReplacements(
base_matchers.SystemBind(search.ROOT_LABEL, self._matcher),
replacements)
def test_from_diff_change(self):
self.assertEqual(
matcher.MatchInfo.from_diff('metavar', 'a\nb\n', 'a\nc\n'),
matcher.MatchInfo(
match.Match(),
bindings={
'metavar.0':
matcher.BoundValue(
match.SpanMatch(
string='b\n',
span=(2, 4),
))
},
replacements={'metavar.0': formatting.LiteralTemplate('c\n')},
),
)