diff options
Diffstat (limited to 'Lib')
| -rw-r--r-- | Lib/shlex.py | 74 | ||||
| -rw-r--r-- | Lib/test/test_shlex.py | 112 |
2 files changed, 165 insertions, 21 deletions
diff --git a/Lib/shlex.py b/Lib/shlex.py index f083918..e87266f 100644 --- a/Lib/shlex.py +++ b/Lib/shlex.py @@ -5,6 +5,7 @@ # push_source() and pop_source() made explicit by ESR, January 2001. # Posix compliance, split(), string arguments, and # iterator interface by Gustavo Niemeyer, April 2003. +# changes to tokenize more like Posix shells by Vinay Sajip, July 2016. import os import re @@ -17,7 +18,8 @@ __all__ = ["shlex", "split", "quote"] class shlex: "A lexical analyzer class for simple shell-like syntaxes." - def __init__(self, instream=None, infile=None, posix=False): + def __init__(self, instream=None, infile=None, posix=False, + punctuation_chars=False): if isinstance(instream, str): instream = StringIO(instream) if instream is not None: @@ -49,6 +51,19 @@ class shlex: self.token = '' self.filestack = deque() self.source = None + if not punctuation_chars: + punctuation_chars = '' + elif punctuation_chars is True: + punctuation_chars = '();<>|&' + self.punctuation_chars = punctuation_chars + if punctuation_chars: + # _pushback_chars is a push back queue used by lookahead logic + self._pushback_chars = deque() + # these chars added because allowed in file names, args, wildcards + self.wordchars += '~-./*?=' + #remove any punctuation chars from wordchars + t = self.wordchars.maketrans(dict.fromkeys(punctuation_chars)) + self.wordchars = self.wordchars.translate(t) def push_token(self, tok): "Push a token onto the stack popped by the get_token method" @@ -115,12 +130,15 @@ class shlex: quoted = False escapedstate = ' ' while True: - nextchar = self.instream.read(1) + if self.punctuation_chars and self._pushback_chars: + nextchar = self._pushback_chars.pop() + else: + nextchar = self.instream.read(1) if nextchar == '\n': - self.lineno = self.lineno + 1 + self.lineno += 1 if self.debug >= 3: - print("shlex: in state", repr(self.state), \ - "I see character:", repr(nextchar)) + print("shlex: in state %r I see character: %r" % (self.state, + nextchar)) if self.state is None: self.token = '' # past end of file break @@ -137,13 +155,16 @@ class shlex: continue elif nextchar in self.commenters: self.instream.readline() - self.lineno = self.lineno + 1 + self.lineno += 1 elif self.posix and nextchar in self.escape: escapedstate = 'a' self.state = nextchar elif nextchar in self.wordchars: self.token = nextchar self.state = 'a' + elif nextchar in self.punctuation_chars: + self.token = nextchar + self.state = 'c' elif nextchar in self.quotes: if not self.posix: self.token = nextchar @@ -166,17 +187,17 @@ class shlex: raise ValueError("No closing quotation") if nextchar == self.state: if not self.posix: - self.token = self.token + nextchar + self.token += nextchar self.state = ' ' break else: self.state = 'a' - elif self.posix and nextchar in self.escape and \ - self.state in self.escapedquotes: + elif (self.posix and nextchar in self.escape and self.state + in self.escapedquotes): escapedstate = self.state self.state = nextchar else: - self.token = self.token + nextchar + self.token += nextchar elif self.state in self.escape: if not nextchar: # end of file if self.debug >= 2: @@ -185,12 +206,12 @@ class shlex: raise ValueError("No escaped character") # In posix shells, only the quote itself or the escape # character may be escaped within quotes. - if escapedstate in self.quotes and \ - nextchar != self.state and nextchar != escapedstate: - self.token = self.token + self.state - self.token = self.token + nextchar + if (escapedstate in self.quotes and + nextchar != self.state and nextchar != escapedstate): + self.token += self.state + self.token += nextchar self.state = escapedstate - elif self.state == 'a': + elif self.state in ('a', 'c'): if not nextchar: self.state = None # end of file break @@ -204,7 +225,7 @@ class shlex: continue elif nextchar in self.commenters: self.instream.readline() - self.lineno = self.lineno + 1 + self.lineno += 1 if self.posix: self.state = ' ' if self.token or (self.posix and quoted): @@ -216,15 +237,26 @@ class shlex: elif self.posix and nextchar in self.escape: escapedstate = 'a' self.state = nextchar - elif nextchar in self.wordchars or nextchar in self.quotes \ - or self.whitespace_split: - self.token = self.token + nextchar + elif self.state == 'c': + if nextchar in self.punctuation_chars: + self.token += nextchar + else: + if nextchar not in self.whitespace: + self._pushback_chars.append(nextchar) + self.state = ' ' + break + elif (nextchar in self.wordchars or nextchar in self.quotes + or self.whitespace_split): + self.token += nextchar else: - self.pushback.appendleft(nextchar) + if self.punctuation_chars: + self._pushback_chars.append(nextchar) + else: + self.pushback.appendleft(nextchar) if self.debug >= 2: print("shlex: I see punctuation in word state") self.state = ' ' - if self.token: + if self.token or (self.posix and quoted): break # emit current token else: continue diff --git a/Lib/test/test_shlex.py b/Lib/test/test_shlex.py index 4fafdd4..3936c97 100644 --- a/Lib/test/test_shlex.py +++ b/Lib/test/test_shlex.py @@ -173,6 +173,118 @@ class ShlexTest(unittest.TestCase): "%s: %s != %s" % (self.data[i][0], l, self.data[i][1:])) + def testSyntaxSplitAmpersandAndPipe(self): + """Test handling of syntax splitting of &, |""" + # Could take these forms: &&, &, |&, ;&, ;;& + # of course, the same applies to | and || + # these should all parse to the same output + for delimiter in ('&&', '&', '|&', ';&', ';;&', + '||', '|', '&|', ';|', ';;|'): + src = ['echo hi %s echo bye' % delimiter, + 'echo hi%secho bye' % delimiter] + ref = ['echo', 'hi', delimiter, 'echo', 'bye'] + for ss in src: + s = shlex.shlex(ss, punctuation_chars=True) + result = list(s) + self.assertEqual(ref, result, "While splitting '%s'" % ss) + + def testSyntaxSplitSemicolon(self): + """Test handling of syntax splitting of ;""" + # Could take these forms: ;, ;;, ;&, ;;& + # these should all parse to the same output + for delimiter in (';', ';;', ';&', ';;&'): + src = ['echo hi %s echo bye' % delimiter, + 'echo hi%s echo bye' % delimiter, + 'echo hi%secho bye' % delimiter] + ref = ['echo', 'hi', delimiter, 'echo', 'bye'] + for ss in src: + s = shlex.shlex(ss, punctuation_chars=True) + result = list(s) + self.assertEqual(ref, result, "While splitting '%s'" % ss) + + def testSyntaxSplitRedirect(self): + """Test handling of syntax splitting of >""" + # of course, the same applies to <, | + # these should all parse to the same output + for delimiter in ('<', '|'): + src = ['echo hi %s out' % delimiter, + 'echo hi%s out' % delimiter, + 'echo hi%sout' % delimiter] + ref = ['echo', 'hi', delimiter, 'out'] + for ss in src: + s = shlex.shlex(ss, punctuation_chars=True) + result = list(s) + self.assertEqual(ref, result, "While splitting '%s'" % ss) + + def testSyntaxSplitParen(self): + """Test handling of syntax splitting of ()""" + # these should all parse to the same output + src = ['( echo hi )', + '(echo hi)'] + ref = ['(', 'echo', 'hi', ')'] + for ss in src: + s = shlex.shlex(ss, punctuation_chars=True) + result = list(s) + self.assertEqual(ref, result, "While splitting '%s'" % ss) + + def testSyntaxSplitCustom(self): + """Test handling of syntax splitting with custom chars""" + ref = ['~/a', '&', '&', 'b-c', '--color=auto', '||', 'd', '*.py?'] + ss = "~/a && b-c --color=auto || d *.py?" + s = shlex.shlex(ss, punctuation_chars="|") + result = list(s) + self.assertEqual(ref, result, "While splitting '%s'" % ss) + + def testTokenTypes(self): + """Test that tokens are split with types as expected.""" + for source, expected in ( + ('a && b || c', + [('a', 'a'), ('&&', 'c'), ('b', 'a'), + ('||', 'c'), ('c', 'a')]), + ): + s = shlex.shlex(source, punctuation_chars=True) + observed = [] + while True: + t = s.get_token() + if t == s.eof: + break + if t[0] in s.punctuation_chars: + tt = 'c' + else: + tt = 'a' + observed.append((t, tt)) + self.assertEqual(observed, expected) + + def testPunctuationInWordChars(self): + """Test that any punctuation chars are removed from wordchars""" + s = shlex.shlex('a_b__c', punctuation_chars='_') + self.assertNotIn('_', s.wordchars) + self.assertEqual(list(s), ['a', '_', 'b', '__', 'c']) + + def testPunctuationWithWhitespaceSplit(self): + """Test that with whitespace_split, behaviour is as expected""" + s = shlex.shlex('a && b || c', punctuation_chars='&') + # whitespace_split is False, so splitting will be based on + # punctuation_chars + self.assertEqual(list(s), ['a', '&&', 'b', '|', '|', 'c']) + s = shlex.shlex('a && b || c', punctuation_chars='&') + s.whitespace_split = True + # whitespace_split is True, so splitting will be based on + # white space + self.assertEqual(list(s), ['a', '&&', 'b', '||', 'c']) + + def testEmptyStringHandling(self): + """Test that parsing of empty strings is correctly handled.""" + # see Issue #21999 + expected = ['', ')', 'abc'] + for punct in (False, True): + s = shlex.shlex("'')abc", posix=True, punctuation_chars=punct) + slist = list(s) + self.assertEqual(slist, expected) + expected = ["''", ')', 'abc'] + s = shlex.shlex("'')abc", punctuation_chars=True) + self.assertEqual(list(s), expected) + def testQuote(self): safeunquoted = string.ascii_letters + string.digits + '@%_-+=:,./' unicode_sample = '\xe9\xe0\xdf' # e + acute accent, a + grave, sharp s |