From d39d608c34fa524f95bd4d749fef959f30e0d5fc Mon Sep 17 00:00:00 2001 From: Serhiy Storchaka Date: Wed, 10 May 2017 06:05:20 +0300 Subject: [PATCH] [3.6] bpo-30298: Weaken the condition of deprecation warnings for inline modifiers. (GH-1490) Now allowed several subsequential inline modifiers at the start of the pattern (e.g. '(?i)(?s)...'). In verbose mode whitespaces and comments now are allowed before and between inline modifiers (e.g. '(?x) (?i) (?s)...').. (cherry picked from commit 305ccbe27ea5ba82fd2d8c32ec739f980e524330) --- Lib/sre_parse.py | 12 ++++----- Lib/test/test_re.py | 59 ++++++++++++++++++++++++++++++++++----------- Misc/NEWS | 6 +++++ 3 files changed, 56 insertions(+), 21 deletions(-) diff --git a/Lib/sre_parse.py b/Lib/sre_parse.py index 6aa49c3bf6f8ed1..e1c749634b71fe7 100644 --- a/Lib/sre_parse.py +++ b/Lib/sre_parse.py @@ -412,7 +412,7 @@ def _parse_sub(source, state, verbose, nested=True): sourcematch = source.match start = source.tell() while True: - itemsappend(_parse(source, state, verbose)) + itemsappend(_parse(source, state, verbose, not nested and not items)) if not sourcematch("|"): break @@ -466,7 +466,7 @@ def _parse_sub_cond(source, state, condgroup, verbose): subpattern.append((GROUPREF_EXISTS, (condgroup, item_yes, item_no))) return subpattern -def _parse(source, state, verbose): +def _parse(source, state, verbose, first=False): # parse a simple pattern subpattern = SubPattern(state) @@ -730,10 +730,9 @@ def _parse(source, state, verbose): state.checklookbehindgroup(condgroup, source) elif char in FLAGS or char == "-": # flags - pos = source.pos flags = _parse_flags(source, state, char) if flags is None: # global flags - if pos != 3: # "(?x" + if not first or subpattern: import warnings warnings.warn( 'Flags not at the start of the expression %s%s' % ( @@ -742,6 +741,8 @@ def _parse(source, state, verbose): ), DeprecationWarning, stacklevel=7 ) + if (state.flags & SRE_FLAG_VERBOSE) and not verbose: + raise Verbose continue add_flags, del_flags = flags group = None @@ -795,9 +796,6 @@ def _parse_flags(source, state, char): msg = "unknown flag" if char.isalpha() else "missing -, : or )" raise source.error(msg, len(char)) if char == ")": - if ((add_flags & SRE_FLAG_VERBOSE) and - not (state.flags & SRE_FLAG_VERBOSE)): - raise Verbose state.flags |= add_flags return None if add_flags & GLOBAL_FLAGS: diff --git a/Lib/test/test_re.py b/Lib/test/test_re.py index b945cf094e99c17..c52417ba000ebca 100644 --- a/Lib/test/test_re.py +++ b/Lib/test/test_re.py @@ -1303,32 +1303,43 @@ def test_inline_flags(self): upper_char = '\u1ea0' # Latin Capital Letter A with Dot Below lower_char = '\u1ea1' # Latin Small Letter A with Dot Below - p = re.compile(upper_char, re.I | re.U) - q = p.match(lower_char) + p = re.compile('.' + upper_char, re.I | re.S) + q = p.match('\n' + lower_char) self.assertTrue(q) - p = re.compile(lower_char, re.I | re.U) - q = p.match(upper_char) + p = re.compile('.' + lower_char, re.I | re.S) + q = p.match('\n' + upper_char) self.assertTrue(q) - p = re.compile('(?i)' + upper_char, re.U) - q = p.match(lower_char) + p = re.compile('(?i).' + upper_char, re.S) + q = p.match('\n' + lower_char) self.assertTrue(q) - p = re.compile('(?i)' + lower_char, re.U) - q = p.match(upper_char) + p = re.compile('(?i).' + lower_char, re.S) + q = p.match('\n' + upper_char) self.assertTrue(q) - p = re.compile('(?iu)' + upper_char) - q = p.match(lower_char) + p = re.compile('(?is).' + upper_char) + q = p.match('\n' + lower_char) self.assertTrue(q) - p = re.compile('(?iu)' + lower_char) - q = p.match(upper_char) + p = re.compile('(?is).' + lower_char) + q = p.match('\n' + upper_char) self.assertTrue(q) - self.assertTrue(re.match('(?ixu) ' + upper_char, lower_char)) - self.assertTrue(re.match('(?ixu) ' + lower_char, upper_char)) + p = re.compile('(?s)(?i).' + upper_char) + q = p.match('\n' + lower_char) + self.assertTrue(q) + + p = re.compile('(?s)(?i).' + lower_char) + q = p.match('\n' + upper_char) + self.assertTrue(q) + + self.assertTrue(re.match('(?ix) ' + upper_char, lower_char)) + self.assertTrue(re.match('(?ix) ' + lower_char, upper_char)) + self.assertTrue(re.match(' (?i) ' + upper_char, lower_char, re.X)) + self.assertTrue(re.match('(?x) (?i) ' + upper_char, lower_char)) + self.assertTrue(re.match(' (?x) (?i) ' + upper_char, lower_char, re.X)) p = upper_char + '(?i)' with self.assertWarns(DeprecationWarning) as warns: @@ -1346,6 +1357,26 @@ def test_inline_flags(self): 'Flags not at the start of the expression %s (truncated)' % p[:20] ) + with self.assertWarns(DeprecationWarning): + self.assertTrue(re.match('(?s).(?i)' + upper_char, '\n' + lower_char)) + with self.assertWarns(DeprecationWarning): + self.assertTrue(re.match('(?i) ' + upper_char + ' (?x)', lower_char)) + with self.assertWarns(DeprecationWarning): + self.assertTrue(re.match(' (?x) (?i) ' + upper_char, lower_char)) + with self.assertWarns(DeprecationWarning): + self.assertTrue(re.match('^(?i)' + upper_char, lower_char)) + with self.assertWarns(DeprecationWarning): + self.assertTrue(re.match('$|(?i)' + upper_char, lower_char)) + with self.assertWarns(DeprecationWarning): + self.assertTrue(re.match('(?:(?i)' + upper_char + ')', lower_char)) + with self.assertWarns(DeprecationWarning): + self.assertTrue(re.fullmatch('(^)?(?(1)(?i)' + upper_char + ')', + lower_char)) + with self.assertWarns(DeprecationWarning): + self.assertTrue(re.fullmatch('($)?(?(1)|(?i)' + upper_char + ')', + lower_char)) + + def test_dollar_matches_twice(self): "$ matches the end of string, and just before the terminating \n" pattern = re.compile('$') diff --git a/Misc/NEWS b/Misc/NEWS index 64974ef2eb2260a..e7090fc17840abd 100644 --- a/Misc/NEWS +++ b/Misc/NEWS @@ -36,6 +36,12 @@ Core and Builtins Library ------- +- bpo-30298: Weaken the condition of deprecation warnings for inline modifiers. + Now allowed several subsequential inline modifiers at the start of the + pattern (e.g. ``'(?i)(?s)...'``). In verbose mode whitespaces and comments + now are allowed before and between inline modifiers (e.g. + ``'(?x) (?i) (?s)...'``). + - bpo-29990: Fix range checking in GB18030 decoder. Original patch by Ma Lin. - Revert bpo-26293 for zipfile breakage. See also bpo-29094.