[3.6] bpo-30298: Weaken the condition of deprecation warnings for inline modifiers. (GH-1490) (#1525)
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)
diff --git a/Lib/sre_parse.py b/Lib/sre_parse.py
index 6aa49c3..e1c7496 100644
--- a/Lib/sre_parse.py
+++ b/Lib/sre_parse.py
@@ -412,7 +412,7 @@
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 @@
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 @@
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 @@
),
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 @@
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: