Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 1 | import string |
| 2 | import re |
| 3 | import sys |
| 4 | |
| 5 | # Reason last stmt is continued (or C_NONE if it's not). |
| 6 | C_NONE, C_BACKSLASH, C_STRING, C_BRACKET = range(4) |
| 7 | |
| 8 | if 0: # for throwaway debugging output |
| 9 | def dump(*stuff): |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 10 | sys.__stdout__.write(string.join(map(str, stuff), " ") + "\n") |
| 11 | |
Guido van Rossum | f4a1508 | 1999-06-03 14:32:16 +0000 | [diff] [blame] | 12 | # Find what looks like the start of a popular stmt. |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 13 | |
Guido van Rossum | f4a1508 | 1999-06-03 14:32:16 +0000 | [diff] [blame] | 14 | _synchre = re.compile(r""" |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 15 | ^ |
| 16 | [ \t]* |
Guido van Rossum | 729afc1 | 1999-06-07 14:28:14 +0000 | [diff] [blame] | 17 | (?: if |
| 18 | | for |
| 19 | | while |
| 20 | | else |
| 21 | | def |
| 22 | | return |
| 23 | | assert |
| 24 | | break |
| 25 | | class |
| 26 | | continue |
| 27 | | elif |
| 28 | | try |
| 29 | | except |
| 30 | | raise |
| 31 | | import |
Tim Peters | 82ac8d1 | 2001-06-19 00:28:47 +0000 | [diff] [blame] | 32 | | yield |
Guido van Rossum | 729afc1 | 1999-06-07 14:28:14 +0000 | [diff] [blame] | 33 | ) |
Guido van Rossum | f4a1508 | 1999-06-03 14:32:16 +0000 | [diff] [blame] | 34 | \b |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 35 | """, re.VERBOSE | re.MULTILINE).search |
| 36 | |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 37 | # Match blank line or non-indenting comment line. |
| 38 | |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 39 | _junkre = re.compile(r""" |
| 40 | [ \t]* |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 41 | (?: \# \S .* )? |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 42 | \n |
| 43 | """, re.VERBOSE).match |
| 44 | |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 45 | # Match any flavor of string; the terminating quote is optional |
| 46 | # so that we're robust in the face of incomplete program text. |
| 47 | |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 48 | _match_stringre = re.compile(r""" |
| 49 | \""" [^"\\]* (?: |
| 50 | (?: \\. | "(?!"") ) |
| 51 | [^"\\]* |
| 52 | )* |
| 53 | (?: \""" )? |
| 54 | |
| 55 | | " [^"\\\n]* (?: \\. [^"\\\n]* )* "? |
| 56 | |
| 57 | | ''' [^'\\]* (?: |
| 58 | (?: \\. | '(?!'') ) |
| 59 | [^'\\]* |
| 60 | )* |
| 61 | (?: ''' )? |
| 62 | |
| 63 | | ' [^'\\\n]* (?: \\. [^'\\\n]* )* '? |
| 64 | """, re.VERBOSE | re.DOTALL).match |
| 65 | |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 66 | # Match a line that starts with something interesting; |
| 67 | # used to find the first item of a bracket structure. |
| 68 | |
| 69 | _itemre = re.compile(r""" |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 70 | [ \t]* |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 71 | [^\s#\\] # if we match, m.end()-1 is the interesting char |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 72 | """, re.VERBOSE).match |
| 73 | |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 74 | # Match start of stmts that should be followed by a dedent. |
| 75 | |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 76 | _closere = re.compile(r""" |
| 77 | \s* |
| 78 | (?: return |
| 79 | | break |
| 80 | | continue |
| 81 | | raise |
| 82 | | pass |
| 83 | ) |
| 84 | \b |
| 85 | """, re.VERBOSE).match |
| 86 | |
Guido van Rossum | 9428fa6 | 2000-03-03 14:51:11 +0000 | [diff] [blame] | 87 | # Chew up non-special chars as quickly as possible. If match is |
| 88 | # successful, m.end() less 1 is the index of the last boring char |
| 89 | # matched. If match is unsuccessful, the string starts with an |
| 90 | # interesting char. |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 91 | |
| 92 | _chew_ordinaryre = re.compile(r""" |
Guido van Rossum | 9428fa6 | 2000-03-03 14:51:11 +0000 | [diff] [blame] | 93 | [^[\](){}#'"\\]+ |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 94 | """, re.VERBOSE).match |
| 95 | |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 96 | # Build translation table to map uninteresting chars to "x", open |
| 97 | # brackets to "(", and close brackets to ")". |
| 98 | |
| 99 | _tran = ['x'] * 256 |
| 100 | for ch in "({[": |
| 101 | _tran[ord(ch)] = '(' |
| 102 | for ch in ")}]": |
| 103 | _tran[ord(ch)] = ')' |
| 104 | for ch in "\"'\\\n#": |
| 105 | _tran[ord(ch)] = ch |
| 106 | _tran = string.join(_tran, '') |
| 107 | del ch |
| 108 | |
Fred Drake | f5d2fdf | 2001-02-16 22:13:48 +0000 | [diff] [blame] | 109 | try: |
| 110 | UnicodeType = type(unicode("")) |
| 111 | except NameError: |
| 112 | UnicodeType = None |
| 113 | |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 114 | class Parser: |
| 115 | |
| 116 | def __init__(self, indentwidth, tabwidth): |
| 117 | self.indentwidth = indentwidth |
| 118 | self.tabwidth = tabwidth |
| 119 | |
| 120 | def set_str(self, str): |
| 121 | assert len(str) == 0 or str[-1] == '\n' |
Fred Drake | f5d2fdf | 2001-02-16 22:13:48 +0000 | [diff] [blame] | 122 | if type(str) is UnicodeType: |
Tim Peters | f2fba87 | 2000-10-06 23:09:00 +0000 | [diff] [blame] | 123 | # The parse functions have no idea what to do with Unicode, so |
| 124 | # replace all Unicode characters with "x". This is "safe" |
| 125 | # so long as the only characters germane to parsing the structure |
| 126 | # of Python are 7-bit ASCII. It's *necessary* because Unicode |
| 127 | # strings don't have a .translate() method that supports |
| 128 | # deletechars. |
| 129 | uniphooey = str |
| 130 | str = [] |
| 131 | push = str.append |
| 132 | for raw in map(ord, uniphooey): |
| 133 | push(raw < 127 and chr(raw) or "x") |
| 134 | str = "".join(str) |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 135 | self.str = str |
| 136 | self.study_level = 0 |
| 137 | |
Guido van Rossum | f4a1508 | 1999-06-03 14:32:16 +0000 | [diff] [blame] | 138 | # Return index of a good place to begin parsing, as close to the |
| 139 | # end of the string as possible. This will be the start of some |
Guido van Rossum | 729afc1 | 1999-06-07 14:28:14 +0000 | [diff] [blame] | 140 | # popular stmt like "if" or "def". Return None if none found: |
| 141 | # the caller should pass more prior context then, if possible, or |
| 142 | # if not (the entire program text up until the point of interest |
| 143 | # has already been tried) pass 0 to set_lo. |
Guido van Rossum | f4a1508 | 1999-06-03 14:32:16 +0000 | [diff] [blame] | 144 | # |
| 145 | # This will be reliable iff given a reliable is_char_in_string |
Guido van Rossum | 729afc1 | 1999-06-07 14:28:14 +0000 | [diff] [blame] | 146 | # function, meaning that when it says "no", it's absolutely |
| 147 | # guaranteed that the char is not in a string. |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 148 | # |
| 149 | # Ack, hack: in the shell window this kills us, because there's |
| 150 | # no way to tell the differences between output, >>> etc and |
| 151 | # user input. Indeed, IDLE's first output line makes the rest |
| 152 | # look like it's in an unclosed paren!: |
| 153 | # Python 1.5.2 (#0, Apr 13 1999, ... |
| 154 | |
Guido van Rossum | 729afc1 | 1999-06-07 14:28:14 +0000 | [diff] [blame] | 155 | def find_good_parse_start(self, use_ps1, is_char_in_string=None, |
| 156 | _rfind=string.rfind, |
Guido van Rossum | f4a1508 | 1999-06-03 14:32:16 +0000 | [diff] [blame] | 157 | _synchre=_synchre): |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 158 | str, pos = self.str, None |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 159 | if use_ps1: |
Guido van Rossum | 729afc1 | 1999-06-07 14:28:14 +0000 | [diff] [blame] | 160 | # shell window |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 161 | ps1 = '\n' + sys.ps1 |
Guido van Rossum | 729afc1 | 1999-06-07 14:28:14 +0000 | [diff] [blame] | 162 | i = _rfind(str, ps1) |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 163 | if i >= 0: |
| 164 | pos = i + len(ps1) |
Guido van Rossum | 729afc1 | 1999-06-07 14:28:14 +0000 | [diff] [blame] | 165 | # make it look like there's a newline instead |
| 166 | # of ps1 at the start -- hacking here once avoids |
| 167 | # repeated hackery later |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 168 | self.str = str[:pos-1] + '\n' + str[pos:] |
Guido van Rossum | 729afc1 | 1999-06-07 14:28:14 +0000 | [diff] [blame] | 169 | return pos |
| 170 | |
| 171 | # File window -- real work. |
| 172 | if not is_char_in_string: |
| 173 | # no clue -- make the caller pass everything |
| 174 | return None |
| 175 | |
| 176 | # Peek back from the end for a good place to start, |
| 177 | # but don't try too often; pos will be left None, or |
| 178 | # bumped to a legitimate synch point. |
| 179 | limit = len(str) |
| 180 | for tries in range(5): |
| 181 | i = _rfind(str, ":\n", 0, limit) |
| 182 | if i < 0: |
| 183 | break |
| 184 | i = _rfind(str, '\n', 0, i) + 1 # start of colon line |
| 185 | m = _synchre(str, i, limit) |
| 186 | if m and not is_char_in_string(m.start()): |
| 187 | pos = m.start() |
| 188 | break |
| 189 | limit = i |
| 190 | if pos is None: |
| 191 | # Nothing looks like a block-opener, or stuff does |
| 192 | # but is_char_in_string keeps returning true; most likely |
| 193 | # we're in or near a giant string, the colorizer hasn't |
| 194 | # caught up enough to be helpful, or there simply *aren't* |
| 195 | # any interesting stmts. In any of these cases we're |
| 196 | # going to have to parse the whole thing to be sure, so |
| 197 | # give it one last try from the start, but stop wasting |
| 198 | # time here regardless of the outcome. |
| 199 | m = _synchre(str) |
| 200 | if m and not is_char_in_string(m.start()): |
| 201 | pos = m.start() |
| 202 | return pos |
| 203 | |
| 204 | # Peeking back worked; look forward until _synchre no longer |
| 205 | # matches. |
| 206 | i = pos + 1 |
| 207 | while 1: |
| 208 | m = _synchre(str, i) |
| 209 | if m: |
| 210 | s, i = m.span() |
| 211 | if not is_char_in_string(s): |
| 212 | pos = s |
| 213 | else: |
| 214 | break |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 215 | return pos |
| 216 | |
| 217 | # Throw away the start of the string. Intended to be called with |
Guido van Rossum | f4a1508 | 1999-06-03 14:32:16 +0000 | [diff] [blame] | 218 | # find_good_parse_start's result. |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 219 | |
| 220 | def set_lo(self, lo): |
| 221 | assert lo == 0 or self.str[lo-1] == '\n' |
| 222 | if lo > 0: |
| 223 | self.str = self.str[lo:] |
| 224 | |
| 225 | # As quickly as humanly possible <wink>, find the line numbers (0- |
| 226 | # based) of the non-continuation lines. |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 227 | # Creates self.{goodlines, continuation}. |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 228 | |
| 229 | def _study1(self, _replace=string.replace, _find=string.find): |
| 230 | if self.study_level >= 1: |
| 231 | return |
| 232 | self.study_level = 1 |
| 233 | |
| 234 | # Map all uninteresting characters to "x", all open brackets |
| 235 | # to "(", all close brackets to ")", then collapse runs of |
| 236 | # uninteresting characters. This can cut the number of chars |
| 237 | # by a factor of 10-40, and so greatly speed the following loop. |
| 238 | str = self.str |
| 239 | str = string.translate(str, _tran) |
| 240 | str = _replace(str, 'xxxxxxxx', 'x') |
| 241 | str = _replace(str, 'xxxx', 'x') |
| 242 | str = _replace(str, 'xx', 'x') |
| 243 | str = _replace(str, 'xx', 'x') |
| 244 | str = _replace(str, '\nx', '\n') |
| 245 | # note that replacing x\n with \n would be incorrect, because |
| 246 | # x may be preceded by a backslash |
| 247 | |
| 248 | # March over the squashed version of the program, accumulating |
| 249 | # the line numbers of non-continued stmts, and determining |
| 250 | # whether & why the last stmt is a continuation. |
| 251 | continuation = C_NONE |
| 252 | level = lno = 0 # level is nesting level; lno is line number |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 253 | self.goodlines = goodlines = [0] |
| 254 | push_good = goodlines.append |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 255 | i, n = 0, len(str) |
| 256 | while i < n: |
| 257 | ch = str[i] |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 258 | i = i+1 |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 259 | |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 260 | # cases are checked in decreasing order of frequency |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 261 | if ch == 'x': |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 262 | continue |
| 263 | |
| 264 | if ch == '\n': |
| 265 | lno = lno + 1 |
| 266 | if level == 0: |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 267 | push_good(lno) |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 268 | # else we're in an unclosed bracket structure |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 269 | continue |
| 270 | |
| 271 | if ch == '(': |
| 272 | level = level + 1 |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 273 | continue |
| 274 | |
| 275 | if ch == ')': |
| 276 | if level: |
| 277 | level = level - 1 |
| 278 | # else the program is invalid, but we can't complain |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 279 | continue |
| 280 | |
| 281 | if ch == '"' or ch == "'": |
| 282 | # consume the string |
| 283 | quote = ch |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 284 | if str[i-1:i+2] == quote * 3: |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 285 | quote = quote * 3 |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 286 | w = len(quote) - 1 |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 287 | i = i+w |
| 288 | while i < n: |
| 289 | ch = str[i] |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 290 | i = i+1 |
| 291 | |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 292 | if ch == 'x': |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 293 | continue |
| 294 | |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 295 | if str[i-1:i+w] == quote: |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 296 | i = i+w |
| 297 | break |
| 298 | |
| 299 | if ch == '\n': |
| 300 | lno = lno + 1 |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 301 | if w == 0: |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 302 | # unterminated single-quoted string |
| 303 | if level == 0: |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 304 | push_good(lno) |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 305 | break |
| 306 | continue |
| 307 | |
| 308 | if ch == '\\': |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 309 | assert i < n |
| 310 | if str[i] == '\n': |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 311 | lno = lno + 1 |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 312 | i = i+1 |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 313 | continue |
| 314 | |
| 315 | # else comment char or paren inside string |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 316 | |
| 317 | else: |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 318 | # didn't break out of the loop, so we're still |
| 319 | # inside a string |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 320 | continuation = C_STRING |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 321 | continue # with outer loop |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 322 | |
| 323 | if ch == '#': |
| 324 | # consume the comment |
| 325 | i = _find(str, '\n', i) |
| 326 | assert i >= 0 |
| 327 | continue |
| 328 | |
| 329 | assert ch == '\\' |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 330 | assert i < n |
| 331 | if str[i] == '\n': |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 332 | lno = lno + 1 |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 333 | if i+1 == n: |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 334 | continuation = C_BACKSLASH |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 335 | i = i+1 |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 336 | |
| 337 | # The last stmt may be continued for all 3 reasons. |
| 338 | # String continuation takes precedence over bracket |
| 339 | # continuation, which beats backslash continuation. |
| 340 | if continuation != C_STRING and level > 0: |
| 341 | continuation = C_BRACKET |
| 342 | self.continuation = continuation |
| 343 | |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 344 | # Push the final line number as a sentinel value, regardless of |
| 345 | # whether it's continued. |
| 346 | assert (continuation == C_NONE) == (goodlines[-1] == lno) |
| 347 | if goodlines[-1] != lno: |
| 348 | push_good(lno) |
| 349 | |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 350 | def get_continuation_type(self): |
| 351 | self._study1() |
| 352 | return self.continuation |
| 353 | |
| 354 | # study1 was sufficient to determine the continuation status, |
| 355 | # but doing more requires looking at every character. study2 |
| 356 | # does this for the last interesting statement in the block. |
| 357 | # Creates: |
| 358 | # self.stmt_start, stmt_end |
| 359 | # slice indices of last interesting stmt |
| 360 | # self.lastch |
| 361 | # last non-whitespace character before optional trailing |
| 362 | # comment |
| 363 | # self.lastopenbracketpos |
| 364 | # if continuation is C_BRACKET, index of last open bracket |
| 365 | |
| 366 | def _study2(self, _rfind=string.rfind, _find=string.find, |
| 367 | _ws=string.whitespace): |
| 368 | if self.study_level >= 2: |
| 369 | return |
| 370 | self._study1() |
| 371 | self.study_level = 2 |
| 372 | |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 373 | # Set p and q to slice indices of last interesting stmt. |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 374 | str, goodlines = self.str, self.goodlines |
| 375 | i = len(goodlines) - 1 |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 376 | p = len(str) # index of newest line |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 377 | while i: |
| 378 | assert p |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 379 | # p is the index of the stmt at line number goodlines[i]. |
| 380 | # Move p back to the stmt at line number goodlines[i-1]. |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 381 | q = p |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 382 | for nothing in range(goodlines[i-1], goodlines[i]): |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 383 | # tricky: sets p to 0 if no preceding newline |
| 384 | p = _rfind(str, '\n', 0, p-1) + 1 |
| 385 | # The stmt str[p:q] isn't a continuation, but may be blank |
| 386 | # or a non-indenting comment line. |
| 387 | if _junkre(str, p): |
| 388 | i = i-1 |
| 389 | else: |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 390 | break |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 391 | if i == 0: |
| 392 | # nothing but junk! |
| 393 | assert p == 0 |
| 394 | q = p |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 395 | self.stmt_start, self.stmt_end = p, q |
| 396 | |
| 397 | # Analyze this stmt, to find the last open bracket (if any) |
| 398 | # and last interesting character (if any). |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 399 | lastch = "" |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 400 | stack = [] # stack of open bracket indices |
| 401 | push_stack = stack.append |
| 402 | while p < q: |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 403 | # suck up all except ()[]{}'"#\\ |
| 404 | m = _chew_ordinaryre(str, p, q) |
| 405 | if m: |
Guido van Rossum | 9428fa6 | 2000-03-03 14:51:11 +0000 | [diff] [blame] | 406 | # we skipped at least one boring char |
Guido van Rossum | 7f1cd29 | 2000-03-13 14:50:24 +0000 | [diff] [blame] | 407 | newp = m.end() |
Guido van Rossum | 9428fa6 | 2000-03-03 14:51:11 +0000 | [diff] [blame] | 408 | # back up over totally boring whitespace |
Guido van Rossum | 7f1cd29 | 2000-03-13 14:50:24 +0000 | [diff] [blame] | 409 | i = newp - 1 # index of last boring char |
| 410 | while i >= p and str[i] in " \t\n": |
Guido van Rossum | 9428fa6 | 2000-03-03 14:51:11 +0000 | [diff] [blame] | 411 | i = i-1 |
Guido van Rossum | 7f1cd29 | 2000-03-13 14:50:24 +0000 | [diff] [blame] | 412 | if i >= p: |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 413 | lastch = str[i] |
Guido van Rossum | 7f1cd29 | 2000-03-13 14:50:24 +0000 | [diff] [blame] | 414 | p = newp |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 415 | if p >= q: |
| 416 | break |
| 417 | |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 418 | ch = str[p] |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 419 | |
| 420 | if ch in "([{": |
| 421 | push_stack(p) |
| 422 | lastch = ch |
| 423 | p = p+1 |
| 424 | continue |
| 425 | |
| 426 | if ch in ")]}": |
| 427 | if stack: |
| 428 | del stack[-1] |
| 429 | lastch = ch |
| 430 | p = p+1 |
| 431 | continue |
| 432 | |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 433 | if ch == '"' or ch == "'": |
| 434 | # consume string |
| 435 | # Note that study1 did this with a Python loop, but |
| 436 | # we use a regexp here; the reason is speed in both |
| 437 | # cases; the string may be huge, but study1 pre-squashed |
| 438 | # strings to a couple of characters per line. study1 |
| 439 | # also needed to keep track of newlines, and we don't |
| 440 | # have to. |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 441 | lastch = ch |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 442 | p = _match_stringre(str, p, q).end() |
| 443 | continue |
| 444 | |
| 445 | if ch == '#': |
| 446 | # consume comment and trailing newline |
| 447 | p = _find(str, '\n', p, q) + 1 |
| 448 | assert p > 0 |
| 449 | continue |
| 450 | |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 451 | assert ch == '\\' |
| 452 | p = p+1 # beyond backslash |
| 453 | assert p < q |
| 454 | if str[p] != '\n': |
| 455 | # the program is invalid, but can't complain |
| 456 | lastch = ch + str[p] |
| 457 | p = p+1 # beyond escaped char |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 458 | |
| 459 | # end while p < q: |
| 460 | |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 461 | self.lastch = lastch |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 462 | if stack: |
| 463 | self.lastopenbracketpos = stack[-1] |
| 464 | |
| 465 | # Assuming continuation is C_BRACKET, return the number |
| 466 | # of spaces the next line should be indented. |
| 467 | |
| 468 | def compute_bracket_indent(self, _find=string.find): |
| 469 | self._study2() |
| 470 | assert self.continuation == C_BRACKET |
| 471 | j = self.lastopenbracketpos |
| 472 | str = self.str |
| 473 | n = len(str) |
| 474 | origi = i = string.rfind(str, '\n', 0, j) + 1 |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 475 | j = j+1 # one beyond open bracket |
| 476 | # find first list item; set i to start of its line |
| 477 | while j < n: |
| 478 | m = _itemre(str, j) |
| 479 | if m: |
| 480 | j = m.end() - 1 # index of first interesting char |
| 481 | extra = 0 |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 482 | break |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 483 | else: |
| 484 | # this line is junk; advance to next line |
| 485 | i = j = _find(str, '\n', j) + 1 |
| 486 | else: |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 487 | # nothing interesting follows the bracket; |
| 488 | # reproduce the bracket line's indentation + a level |
| 489 | j = i = origi |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 490 | while str[j] in " \t": |
| 491 | j = j+1 |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 492 | extra = self.indentwidth |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 493 | return len(string.expandtabs(str[i:j], |
| 494 | self.tabwidth)) + extra |
| 495 | |
| 496 | # Return number of physical lines in last stmt (whether or not |
| 497 | # it's an interesting stmt! this is intended to be called when |
| 498 | # continuation is C_BACKSLASH). |
| 499 | |
| 500 | def get_num_lines_in_stmt(self): |
| 501 | self._study1() |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 502 | goodlines = self.goodlines |
| 503 | return goodlines[-1] - goodlines[-2] |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 504 | |
| 505 | # Assuming continuation is C_BACKSLASH, return the number of spaces |
| 506 | # the next line should be indented. Also assuming the new line is |
| 507 | # the first one following the initial line of the stmt. |
| 508 | |
| 509 | def compute_backslash_indent(self): |
| 510 | self._study2() |
| 511 | assert self.continuation == C_BACKSLASH |
| 512 | str = self.str |
| 513 | i = self.stmt_start |
| 514 | while str[i] in " \t": |
| 515 | i = i+1 |
| 516 | startpos = i |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 517 | |
| 518 | # See whether the initial line starts an assignment stmt; i.e., |
| 519 | # look for an = operator |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 520 | endpos = string.find(str, '\n', startpos) + 1 |
| 521 | found = level = 0 |
| 522 | while i < endpos: |
| 523 | ch = str[i] |
| 524 | if ch in "([{": |
| 525 | level = level + 1 |
| 526 | i = i+1 |
| 527 | elif ch in ")]}": |
| 528 | if level: |
| 529 | level = level - 1 |
| 530 | i = i+1 |
| 531 | elif ch == '"' or ch == "'": |
| 532 | i = _match_stringre(str, i, endpos).end() |
| 533 | elif ch == '#': |
| 534 | break |
| 535 | elif level == 0 and ch == '=' and \ |
Guido van Rossum | bbaba85 | 1999-06-01 19:55:34 +0000 | [diff] [blame] | 536 | (i == 0 or str[i-1] not in "=<>!") and \ |
| 537 | str[i+1] != '=': |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 538 | found = 1 |
| 539 | break |
| 540 | else: |
| 541 | i = i+1 |
| 542 | |
| 543 | if found: |
| 544 | # found a legit =, but it may be the last interesting |
| 545 | # thing on the line |
| 546 | i = i+1 # move beyond the = |
| 547 | found = re.match(r"\s*\\", str[i:endpos]) is None |
| 548 | |
| 549 | if not found: |
| 550 | # oh well ... settle for moving beyond the first chunk |
| 551 | # of non-whitespace chars |
| 552 | i = startpos |
| 553 | while str[i] not in " \t\n": |
| 554 | i = i+1 |
| 555 | |
| 556 | return len(string.expandtabs(str[self.stmt_start : |
| 557 | i], |
| 558 | self.tabwidth)) + 1 |
| 559 | |
| 560 | # Return the leading whitespace on the initial line of the last |
| 561 | # interesting stmt. |
| 562 | |
| 563 | def get_base_indent_string(self): |
| 564 | self._study2() |
| 565 | i, n = self.stmt_start, self.stmt_end |
Guido van Rossum | 8113cdc | 1999-06-01 19:49:21 +0000 | [diff] [blame] | 566 | j = i |
| 567 | str = self.str |
| 568 | while j < n and str[j] in " \t": |
| 569 | j = j + 1 |
| 570 | return str[i:j] |
| 571 | |
| 572 | # Did the last interesting stmt open a block? |
| 573 | |
| 574 | def is_block_opener(self): |
| 575 | self._study2() |
| 576 | return self.lastch == ':' |
| 577 | |
| 578 | # Did the last interesting stmt close a block? |
| 579 | |
| 580 | def is_block_closer(self): |
| 581 | self._study2() |
| 582 | return _closere(self.str, self.stmt_start) is not None |
Guido van Rossum | f4a1508 | 1999-06-03 14:32:16 +0000 | [diff] [blame] | 583 | |
| 584 | # index of last open bracket ({[, or None if none |
| 585 | lastopenbracketpos = None |
| 586 | |
| 587 | def get_last_open_bracket_pos(self): |
| 588 | self._study2() |
| 589 | return self.lastopenbracketpos |