diff options
Diffstat (limited to 'Lib/sre_parse.py')
-rw-r--r-- | Lib/sre_parse.py | 227 |
1 files changed, 112 insertions, 115 deletions
diff --git a/Lib/sre_parse.py b/Lib/sre_parse.py index e6f1f1d..0bce71e 100644 --- a/Lib/sre_parse.py +++ b/Lib/sre_parse.py @@ -79,7 +79,7 @@ class Pattern: gid = self.groups self.subpatterns.append(None) if self.groups > MAXGROUPS: - raise error("groups number is too large") + raise error("too many groups") if name is not None: ogid = self.groupdict.get(name, None) if ogid is not None: @@ -235,7 +235,7 @@ class Tokenizer: try: char += self.decoded_string[index] except IndexError: - raise error("bogus escape (end of line)", + raise error("bad escape (end of pattern)", self.string, len(self.string) - 1) from None self.index = index + 1 self.next = char @@ -263,8 +263,13 @@ class Tokenizer: c = self.next self.__next() if c is None: - raise self.error("unterminated name") + if not result: + raise self.error("missing group name") + raise self.error("missing %s, unterminated name" % terminator, + len(result)) if c == terminator: + if not result: + raise self.error("missing group name", 1) break result += c return result @@ -318,19 +323,19 @@ def _class_escape(source, escape): # hexadecimal escape (exactly two digits) escape += source.getwhile(2, HEXDIGITS) if len(escape) != 4: - raise ValueError + raise source.error("incomplete escape %s" % escape, len(escape)) return LITERAL, int(escape[2:], 16) elif c == "u" and source.istext: # unicode escape (exactly four digits) escape += source.getwhile(4, HEXDIGITS) if len(escape) != 6: - raise ValueError + raise source.error("incomplete escape %s" % escape, len(escape)) return LITERAL, int(escape[2:], 16) elif c == "U" and source.istext: # unicode escape (exactly eight digits) escape += source.getwhile(8, HEXDIGITS) if len(escape) != 10: - raise ValueError + raise source.error("incomplete escape %s" % escape, len(escape)) c = int(escape[2:], 16) chr(c) # raise ValueError for invalid code return LITERAL, c @@ -339,7 +344,7 @@ def _class_escape(source, escape): escape += source.getwhile(2, OCTDIGITS) c = int(escape[1:], 8) if c > 0o377: - raise source.error('octal escape value %r outside of ' + raise source.error('octal escape value %s outside of ' 'range 0-0o377' % escape, len(escape)) return LITERAL, c elif c in DIGITS: @@ -352,7 +357,7 @@ def _class_escape(source, escape): return LITERAL, ord(escape[1]) except ValueError: pass - raise source.error("bogus escape: %r" % escape, len(escape)) + raise source.error("bad escape %s" % escape, len(escape)) def _escape(source, escape, state): # handle escape code in expression @@ -368,19 +373,19 @@ def _escape(source, escape, state): # hexadecimal escape escape += source.getwhile(2, HEXDIGITS) if len(escape) != 4: - raise ValueError + raise source.error("incomplete escape %s" % escape, len(escape)) return LITERAL, int(escape[2:], 16) elif c == "u" and source.istext: # unicode escape (exactly four digits) escape += source.getwhile(4, HEXDIGITS) if len(escape) != 6: - raise ValueError + raise source.error("incomplete escape %s" % escape, len(escape)) return LITERAL, int(escape[2:], 16) elif c == "U" and source.istext: # unicode escape (exactly eight digits) escape += source.getwhile(8, HEXDIGITS) if len(escape) != 10: - raise ValueError + raise source.error("incomplete escape %s" % escape, len(escape)) c = int(escape[2:], 16) chr(c) # raise ValueError for invalid code return LITERAL, c @@ -398,7 +403,7 @@ def _escape(source, escape, state): escape += source.get() c = int(escape[1:], 8) if c > 0o377: - raise source.error('octal escape value %r outside of ' + raise source.error('octal escape value %s outside of ' 'range 0-0o377' % escape, len(escape)) return LITERAL, c @@ -406,11 +411,11 @@ def _escape(source, escape, state): group = int(escape[1:]) if group < state.groups: if not state.checkgroup(group): - raise source.error("cannot refer to open group", + raise source.error("cannot refer to an open group", len(escape)) state.checklookbehindgroup(group, source) return GROUPREF, group - raise ValueError + raise source.error("invalid group reference", len(escape)) if len(escape) == 2: if c in ASCIILETTERS: import warnings @@ -419,7 +424,7 @@ def _escape(source, escape, state): return LITERAL, ord(escape[1]) except ValueError: pass - raise source.error("bogus escape: %r" % escape, len(escape)) + raise source.error("bad escape %s" % escape, len(escape)) def _parse_sub(source, state, nested=True): # parse an alternation: a|b|c @@ -427,12 +432,11 @@ def _parse_sub(source, state, nested=True): items = [] itemsappend = items.append sourcematch = source.match + start = source.tell() while True: itemsappend(_parse(source, state)) if not sourcematch("|"): break - if nested and source.next is not None and source.next != ")": - raise source.error("pattern not properly closed") if len(items) == 1: return items[0] @@ -480,8 +484,6 @@ def _parse_sub_cond(source, state, condgroup): raise source.error("conditional backref with more than two branches") else: item_no = None - if source.next is not None and source.next != ")": - raise source.error("pattern not properly closed") subpattern = SubPattern(state) subpattern.append((GROUPREF_EXISTS, (condgroup, item_yes, item_no))) return subpattern @@ -526,6 +528,7 @@ def _parse(source, state): subpatternappend((LITERAL, _ord(this))) elif this == "[": + here = source.tell() - 1 # character set set = [] setappend = set.append @@ -538,7 +541,8 @@ def _parse(source, state): while True: this = sourceget() if this is None: - raise source.error("unexpected end of regular expression") + raise source.error("unterminated character set", + source.tell() - here) if this == "]" and set != start: break elif this[0] == "\\": @@ -547,25 +551,28 @@ def _parse(source, state): code1 = LITERAL, _ord(this) if sourcematch("-"): # potential range - this = sourceget() - if this is None: - raise source.error("unexpected end of regular expression") - if this == "]": + that = sourceget() + if that is None: + raise source.error("unterminated character set", + source.tell() - here) + if that == "]": if code1[0] is IN: code1 = code1[1][0] setappend(code1) setappend((LITERAL, _ord("-"))) break - if this[0] == "\\": - code2 = _class_escape(source, this) + if that[0] == "\\": + code2 = _class_escape(source, that) else: - code2 = LITERAL, _ord(this) + code2 = LITERAL, _ord(that) if code1[0] != LITERAL or code2[0] != LITERAL: - raise source.error("bad character range", len(this)) + msg = "bad character range %s-%s" % (this, that) + raise source.error(msg, len(this) + 1 + len(that)) lo = code1[1] hi = code2[1] if hi < lo: - raise source.error("bad character range", len(this)) + msg = "bad character range %s-%s" % (this, that) + raise source.error(msg, len(this) + 1 + len(that)) setappend((RANGE, (lo, hi))) else: if code1[0] is IN: @@ -617,10 +624,10 @@ def _parse(source, state): if max >= MAXREPEAT: raise OverflowError("the repetition number is too large") if max < min: - raise source.error("bad repeat interval", + raise source.error("min repeat greater than max repeat", source.tell() - here) else: - raise source.error("not supported", len(this)) + raise AssertionError("unsupported quantifier %r" % (char,)) # figure out which item to repeat if subpattern: item = subpattern[-1:] @@ -641,39 +648,32 @@ def _parse(source, state): subpatternappend((ANY, None)) elif this == "(": - group = 1 + start = source.tell() - 1 + group = True name = None condgroup = None if sourcematch("?"): - group = 0 # options char = sourceget() if char is None: - raise self.error("unexpected end of pattern") + raise source.error("unexpected end of pattern") if char == "P": # python extensions if sourcematch("<"): # named group: skip forward to end of name name = source.getuntil(">") - group = 1 - if not name: - raise source.error("missing group name", 1) if not name.isidentifier(): - raise source.error("bad character in group name " - "%r" % name, - len(name) + 1) + msg = "bad character in group name %r" % name + raise source.error(msg, len(name) + 1) elif sourcematch("="): # named backreference name = source.getuntil(")") - if not name: - raise source.error("missing group name", 1) if not name.isidentifier(): - raise source.error("bad character in backref " - "group name %r" % name, - len(name) + 1) + msg = "bad character in group name %r" % name + raise source.error(msg, len(name) + 1) gid = state.groupdict.get(name) if gid is None: - msg = "unknown group name: {0!r}".format(name) + msg = "unknown group name %r" % name raise source.error(msg, len(name) + 1) state.checklookbehindgroup(gid, source) subpatternappend((GROUPREF, gid)) @@ -682,16 +682,17 @@ def _parse(source, state): char = sourceget() if char is None: raise source.error("unexpected end of pattern") - raise source.error("unknown specifier: ?P%s" % char, - len(char)) + raise source.error("unknown extension ?P" + char, + len(char) + 2) elif char == ":": # non-capturing group - group = 2 + group = None elif char == "#": # comment while True: if source.next is None: - raise source.error("unbalanced parenthesis") + raise source.error("missing ), unterminated comment", + source.tell() - start) if sourceget() == ")": break continue @@ -700,8 +701,11 @@ def _parse(source, state): dir = 1 if char == "<": char = sourceget() - if char is None or char not in "=!": - raise source.error("syntax error") + if char is None: + raise source.error("unexpected end of pattern") + if char not in "=!": + raise source.error("unknown extension ?<" + char, + len(char) + 2) dir = -1 # lookbehind lookbehindgroups = state.lookbehindgroups if lookbehindgroups is None: @@ -711,7 +715,8 @@ def _parse(source, state): if lookbehindgroups is None: state.lookbehindgroups = None if not sourcematch(")"): - raise source.error("unbalanced parenthesis") + raise source.error("missing ), unterminated subpattern", + source.tell() - start) if char == "=": subpatternappend((ASSERT, (dir, p))) else: @@ -720,13 +725,11 @@ def _parse(source, state): elif char == "(": # conditional backreference group condname = source.getuntil(")") - group = 2 - if not condname: - raise source.error("missing group name", 1) + group = None if condname.isidentifier(): condgroup = state.groupdict.get(condname) if condgroup is None: - msg = "unknown group name: {0!r}".format(condname) + msg = "unknown group name %r" % condname raise source.error(msg, len(condname) + 1) else: try: @@ -734,50 +737,48 @@ def _parse(source, state): if condgroup < 0: raise ValueError except ValueError: - raise source.error("bad character in group name", - len(condname) + 1) + msg = "bad character in group name %r" % condname + raise source.error(msg, len(condname) + 1) from None if not condgroup: raise source.error("bad group number", len(condname) + 1) if condgroup >= MAXGROUPS: - raise source.error("the group number is too large", + raise source.error("invalid group reference", len(condname) + 1) state.checklookbehindgroup(condgroup, source) elif char in FLAGS: # flags - state.flags |= FLAGS[char] - while source.next in FLAGS: - state.flags |= FLAGS[sourceget()] + while True: + state.flags |= FLAGS[char] + char = sourceget() + if char is None: + raise source.error("missing )") + if char == ")": + break + if char not in FLAGS: + raise source.error("unknown flag", len(char)) verbose = state.flags & SRE_FLAG_VERBOSE + continue else: - raise source.error("unexpected end of pattern") - if group: - # parse group contents - if group == 2: - # anonymous group - group = None - else: - try: - group = state.opengroup(name) - except error as err: - raise source.error(err.msg, len(name) + 1) - if condgroup: - p = _parse_sub_cond(source, state, condgroup) - else: - p = _parse_sub(source, state) - if not sourcematch(")"): - raise source.error("unbalanced parenthesis") - if group is not None: - state.closegroup(group, p) - subpatternappend((SUBPATTERN, (group, p))) + raise source.error("unknown extension ?" + char, + len(char) + 1) + + # parse group contents + if group is not None: + try: + group = state.opengroup(name) + except error as err: + raise source.error(err.msg, len(name) + 1) from None + if condgroup: + p = _parse_sub_cond(source, state, condgroup) else: - while True: - char = sourceget() - if char is None: - raise source.error("unexpected end of pattern") - if char == ")": - break - raise source.error("unknown extension", len(char)) + p = _parse_sub(source, state) + if not source.match(")"): + raise source.error("missing ), unterminated subpattern", + source.tell() - start) + if group is not None: + state.closegroup(group, p) + subpatternappend((SUBPATTERN, (group, p))) elif this == "^": subpatternappend((AT, AT_BEGINNING)) @@ -786,7 +787,7 @@ def _parse(source, state): subpattern.append((AT, AT_END)) else: - raise source.error("parser error", len(this)) + raise AssertionError("unsupported special character %r" % (char,)) return subpattern @@ -804,7 +805,7 @@ def fix_flags(src, flags): raise ValueError("ASCII and UNICODE flags are incompatible") else: if flags & SRE_FLAG_UNICODE: - raise ValueError("can't use UNICODE flag with a bytes pattern") + raise ValueError("cannot use UNICODE flag with a bytes pattern") if flags & SRE_FLAG_LOCALE and flags & SRE_FLAG_ASCII: import warnings warnings.warn("ASCII and LOCALE flags are incompatible. " @@ -826,11 +827,8 @@ def parse(str, flags=0, pattern=None): p.pattern.flags = fix_flags(str, p.pattern.flags) if source.next is not None: - if source.next == ")": - raise source.error("unbalanced parenthesis") - else: - raise source.error("bogus characters at end of regular expression", - len(tail)) + assert source.next == ")" + raise source.error("unbalanced parenthesis") if flags & SRE_FLAG_DEBUG: p.dump() @@ -866,26 +864,25 @@ def parse_template(source, pattern): c = this[1] if c == "g": name = "" - if s.match("<"): - name = s.getuntil(">") - if not name: - raise s.error("missing group name", 1) - try: - index = int(name) - if index < 0: - raise s.error("negative group number", len(name) + 1) - if index >= MAXGROUPS: - raise s.error("the group number is too large", - len(name) + 1) - except ValueError: - if not name.isidentifier(): - raise s.error("bad character in group name", - len(name) + 1) + if not s.match("<"): + raise s.error("missing <") + name = s.getuntil(">") + if name.isidentifier(): try: index = pattern.groupindex[name] except KeyError: - msg = "unknown group name: {0!r}".format(name) - raise IndexError(msg) + raise IndexError("unknown group name %r" % name) + else: + try: + index = int(name) + if index < 0: + raise ValueError + except ValueError: + raise s.error("bad character in group name %r" % name, + len(name) + 1) from None + if index >= MAXGROUPS: + raise s.error("invalid group reference", + len(name) + 1) addgroup(index) elif c == "0": if s.next in OCTDIGITS: @@ -903,7 +900,7 @@ def parse_template(source, pattern): isoctal = True c = int(this[1:], 8) if c > 0o377: - raise s.error('octal escape value %r outside of ' + raise s.error('octal escape value %s outside of ' 'range 0-0o377' % this, len(this)) lappend(chr(c)) if not isoctal: |