David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 1 | import re |
| 2 | import sys |
Tal Einat | 9b7f9e6 | 2014-07-16 16:33:36 +0300 | [diff] [blame] | 3 | from collections import Mapping |
| 4 | from functools import partial |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 5 | |
| 6 | # Reason last stmt is continued (or C_NONE if it's not). |
Kurt B. Kaiser | b61602c | 2005-11-15 07:20:06 +0000 | [diff] [blame] | 7 | (C_NONE, C_BACKSLASH, C_STRING_FIRST_LINE, |
| 8 | C_STRING_NEXT_LINES, C_BRACKET) = range(5) |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 9 | |
| 10 | if 0: # for throwaway debugging output |
| 11 | def dump(*stuff): |
Kurt B. Kaiser | 254eb53 | 2002-09-17 03:55:13 +0000 | [diff] [blame] | 12 | sys.__stdout__.write(" ".join(map(str, stuff)) + "\n") |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 13 | |
| 14 | # Find what looks like the start of a popular stmt. |
| 15 | |
| 16 | _synchre = re.compile(r""" |
| 17 | ^ |
| 18 | [ \t]* |
Kurt B. Kaiser | b175445 | 2005-11-18 22:05:48 +0000 | [diff] [blame] | 19 | (?: while |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 20 | | else |
| 21 | | def |
| 22 | | return |
| 23 | | assert |
| 24 | | break |
| 25 | | class |
| 26 | | continue |
| 27 | | elif |
| 28 | | try |
| 29 | | except |
| 30 | | raise |
| 31 | | import |
Kurt B. Kaiser | 752e4d5 | 2001-07-14 04:59:24 +0000 | [diff] [blame] | 32 | | yield |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 33 | ) |
| 34 | \b |
| 35 | """, re.VERBOSE | re.MULTILINE).search |
| 36 | |
| 37 | # Match blank line or non-indenting comment line. |
| 38 | |
| 39 | _junkre = re.compile(r""" |
| 40 | [ \t]* |
| 41 | (?: \# \S .* )? |
| 42 | \n |
| 43 | """, re.VERBOSE).match |
| 44 | |
| 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 | |
| 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 | |
| 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""" |
| 70 | [ \t]* |
| 71 | [^\s#\\] # if we match, m.end()-1 is the interesting char |
| 72 | """, re.VERBOSE).match |
| 73 | |
| 74 | # Match start of stmts that should be followed by a dedent. |
| 75 | |
| 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 | |
| 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. |
| 91 | |
| 92 | _chew_ordinaryre = re.compile(r""" |
| 93 | [^[\](){}#'"\\]+ |
| 94 | """, re.VERBOSE).match |
| 95 | |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 96 | |
Tal Einat | 9b7f9e6 | 2014-07-16 16:33:36 +0300 | [diff] [blame] | 97 | class StringTranslatePseudoMapping(Mapping): |
| 98 | r"""Utility class to be used with str.translate() |
| 99 | |
| 100 | This Mapping class wraps a given dict. When a value for a key is |
| 101 | requested via __getitem__() or get(), the key is looked up in the |
| 102 | given dict. If found there, the value from the dict is returned. |
| 103 | Otherwise, the default value given upon initialization is returned. |
| 104 | |
| 105 | This allows using str.translate() to make some replacements, and to |
| 106 | replace all characters for which no replacement was specified with |
| 107 | a given character instead of leaving them as-is. |
| 108 | |
| 109 | For example, to replace everything except whitespace with 'x': |
| 110 | |
| 111 | >>> whitespace_chars = ' \t\n\r' |
| 112 | >>> preserve_dict = {ord(c): ord(c) for c in whitespace_chars} |
| 113 | >>> mapping = StringTranslatePseudoMapping(preserve_dict, ord('x')) |
| 114 | >>> text = "a + b\tc\nd" |
| 115 | >>> text.translate(mapping) |
| 116 | 'x x x\tx\nx' |
| 117 | """ |
| 118 | def __init__(self, non_defaults, default_value): |
| 119 | self._non_defaults = non_defaults |
| 120 | self._default_value = default_value |
| 121 | |
| 122 | def _get(key, _get=non_defaults.get, _default=default_value): |
| 123 | return _get(key, _default) |
| 124 | self._get = _get |
| 125 | |
| 126 | def __getitem__(self, item): |
| 127 | return self._get(item) |
| 128 | |
| 129 | def __len__(self): |
| 130 | return len(self._non_defaults) |
| 131 | |
| 132 | def __iter__(self): |
| 133 | return iter(self._non_defaults) |
| 134 | |
| 135 | def get(self, key, default=None): |
| 136 | return self._get(key) |
| 137 | |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 138 | |
| 139 | class Parser: |
| 140 | |
| 141 | def __init__(self, indentwidth, tabwidth): |
| 142 | self.indentwidth = indentwidth |
| 143 | self.tabwidth = tabwidth |
| 144 | |
Walter Dörwald | 5de48bd | 2007-06-11 21:38:39 +0000 | [diff] [blame] | 145 | def set_str(self, s): |
| 146 | assert len(s) == 0 or s[-1] == '\n' |
Walter Dörwald | 5de48bd | 2007-06-11 21:38:39 +0000 | [diff] [blame] | 147 | self.str = s |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 148 | self.study_level = 0 |
| 149 | |
| 150 | # Return index of a good place to begin parsing, as close to the |
| 151 | # end of the string as possible. This will be the start of some |
| 152 | # popular stmt like "if" or "def". Return None if none found: |
| 153 | # the caller should pass more prior context then, if possible, or |
| 154 | # if not (the entire program text up until the point of interest |
| 155 | # has already been tried) pass 0 to set_lo. |
| 156 | # |
| 157 | # This will be reliable iff given a reliable is_char_in_string |
| 158 | # function, meaning that when it says "no", it's absolutely |
| 159 | # guaranteed that the char is not in a string. |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 160 | |
Kurt B. Kaiser | b175445 | 2005-11-18 22:05:48 +0000 | [diff] [blame] | 161 | def find_good_parse_start(self, is_char_in_string=None, |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 162 | _synchre=_synchre): |
| 163 | str, pos = self.str, None |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 164 | |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 165 | if not is_char_in_string: |
| 166 | # no clue -- make the caller pass everything |
| 167 | return None |
| 168 | |
| 169 | # Peek back from the end for a good place to start, |
| 170 | # but don't try too often; pos will be left None, or |
| 171 | # bumped to a legitimate synch point. |
| 172 | limit = len(str) |
| 173 | for tries in range(5): |
Kurt B. Kaiser | 254eb53 | 2002-09-17 03:55:13 +0000 | [diff] [blame] | 174 | i = str.rfind(":\n", 0, limit) |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 175 | if i < 0: |
| 176 | break |
Kurt B. Kaiser | 254eb53 | 2002-09-17 03:55:13 +0000 | [diff] [blame] | 177 | i = str.rfind('\n', 0, i) + 1 # start of colon line |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 178 | m = _synchre(str, i, limit) |
| 179 | if m and not is_char_in_string(m.start()): |
| 180 | pos = m.start() |
| 181 | break |
| 182 | limit = i |
| 183 | if pos is None: |
| 184 | # Nothing looks like a block-opener, or stuff does |
| 185 | # but is_char_in_string keeps returning true; most likely |
| 186 | # we're in or near a giant string, the colorizer hasn't |
| 187 | # caught up enough to be helpful, or there simply *aren't* |
| 188 | # any interesting stmts. In any of these cases we're |
| 189 | # going to have to parse the whole thing to be sure, so |
| 190 | # give it one last try from the start, but stop wasting |
| 191 | # time here regardless of the outcome. |
| 192 | m = _synchre(str) |
| 193 | if m and not is_char_in_string(m.start()): |
| 194 | pos = m.start() |
| 195 | return pos |
| 196 | |
| 197 | # Peeking back worked; look forward until _synchre no longer |
| 198 | # matches. |
| 199 | i = pos + 1 |
| 200 | while 1: |
| 201 | m = _synchre(str, i) |
| 202 | if m: |
| 203 | s, i = m.span() |
| 204 | if not is_char_in_string(s): |
| 205 | pos = s |
| 206 | else: |
| 207 | break |
| 208 | return pos |
| 209 | |
| 210 | # Throw away the start of the string. Intended to be called with |
| 211 | # find_good_parse_start's result. |
| 212 | |
| 213 | def set_lo(self, lo): |
| 214 | assert lo == 0 or self.str[lo-1] == '\n' |
| 215 | if lo > 0: |
| 216 | self.str = self.str[lo:] |
| 217 | |
Tal Einat | 9b7f9e6 | 2014-07-16 16:33:36 +0300 | [diff] [blame] | 218 | # Build a translation table to map uninteresting chars to 'x', open |
| 219 | # brackets to '(', close brackets to ')' while preserving quotes, |
| 220 | # backslashes, newlines and hashes. This is to be passed to |
| 221 | # str.translate() in _study1(). |
| 222 | _tran = {} |
| 223 | _tran.update((ord(c), ord('(')) for c in "({[") |
| 224 | _tran.update((ord(c), ord(')')) for c in ")}]") |
| 225 | _tran.update((ord(c), ord(c)) for c in "\"'\\\n#") |
| 226 | _tran = StringTranslatePseudoMapping(_tran, default_value=ord('x')) |
| 227 | |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 228 | # As quickly as humanly possible <wink>, find the line numbers (0- |
| 229 | # based) of the non-continuation lines. |
| 230 | # Creates self.{goodlines, continuation}. |
| 231 | |
Kurt B. Kaiser | 254eb53 | 2002-09-17 03:55:13 +0000 | [diff] [blame] | 232 | def _study1(self): |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 233 | if self.study_level >= 1: |
| 234 | return |
| 235 | self.study_level = 1 |
| 236 | |
| 237 | # Map all uninteresting characters to "x", all open brackets |
| 238 | # to "(", all close brackets to ")", then collapse runs of |
| 239 | # uninteresting characters. This can cut the number of chars |
| 240 | # by a factor of 10-40, and so greatly speed the following loop. |
| 241 | str = self.str |
Tal Einat | 9b7f9e6 | 2014-07-16 16:33:36 +0300 | [diff] [blame] | 242 | str = str.translate(self._tran) |
Kurt B. Kaiser | 254eb53 | 2002-09-17 03:55:13 +0000 | [diff] [blame] | 243 | str = str.replace('xxxxxxxx', 'x') |
| 244 | str = str.replace('xxxx', 'x') |
| 245 | str = str.replace('xx', 'x') |
| 246 | str = str.replace('xx', 'x') |
| 247 | str = str.replace('\nx', '\n') |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 248 | # note that replacing x\n with \n would be incorrect, because |
| 249 | # x may be preceded by a backslash |
| 250 | |
| 251 | # March over the squashed version of the program, accumulating |
| 252 | # the line numbers of non-continued stmts, and determining |
| 253 | # whether & why the last stmt is a continuation. |
| 254 | continuation = C_NONE |
| 255 | level = lno = 0 # level is nesting level; lno is line number |
| 256 | self.goodlines = goodlines = [0] |
| 257 | push_good = goodlines.append |
| 258 | i, n = 0, len(str) |
| 259 | while i < n: |
| 260 | ch = str[i] |
| 261 | i = i+1 |
| 262 | |
| 263 | # cases are checked in decreasing order of frequency |
| 264 | if ch == 'x': |
| 265 | continue |
| 266 | |
| 267 | if ch == '\n': |
| 268 | lno = lno + 1 |
| 269 | if level == 0: |
| 270 | push_good(lno) |
| 271 | # else we're in an unclosed bracket structure |
| 272 | continue |
| 273 | |
| 274 | if ch == '(': |
| 275 | level = level + 1 |
| 276 | continue |
| 277 | |
| 278 | if ch == ')': |
| 279 | if level: |
| 280 | level = level - 1 |
| 281 | # else the program is invalid, but we can't complain |
| 282 | continue |
| 283 | |
| 284 | if ch == '"' or ch == "'": |
| 285 | # consume the string |
| 286 | quote = ch |
| 287 | if str[i-1:i+2] == quote * 3: |
| 288 | quote = quote * 3 |
Kurt B. Kaiser | b61602c | 2005-11-15 07:20:06 +0000 | [diff] [blame] | 289 | firstlno = lno |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 290 | w = len(quote) - 1 |
| 291 | i = i+w |
| 292 | while i < n: |
| 293 | ch = str[i] |
| 294 | i = i+1 |
| 295 | |
| 296 | if ch == 'x': |
| 297 | continue |
| 298 | |
| 299 | if str[i-1:i+w] == quote: |
| 300 | i = i+w |
| 301 | break |
| 302 | |
| 303 | if ch == '\n': |
| 304 | lno = lno + 1 |
| 305 | if w == 0: |
| 306 | # unterminated single-quoted string |
| 307 | if level == 0: |
| 308 | push_good(lno) |
| 309 | break |
| 310 | continue |
| 311 | |
| 312 | if ch == '\\': |
| 313 | assert i < n |
| 314 | if str[i] == '\n': |
| 315 | lno = lno + 1 |
| 316 | i = i+1 |
| 317 | continue |
| 318 | |
| 319 | # else comment char or paren inside string |
| 320 | |
| 321 | else: |
| 322 | # didn't break out of the loop, so we're still |
| 323 | # inside a string |
Kurt B. Kaiser | b61602c | 2005-11-15 07:20:06 +0000 | [diff] [blame] | 324 | if (lno - 1) == firstlno: |
| 325 | # before the previous \n in str, we were in the first |
| 326 | # line of the string |
| 327 | continuation = C_STRING_FIRST_LINE |
| 328 | else: |
| 329 | continuation = C_STRING_NEXT_LINES |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 330 | continue # with outer loop |
| 331 | |
| 332 | if ch == '#': |
| 333 | # consume the comment |
Kurt B. Kaiser | 254eb53 | 2002-09-17 03:55:13 +0000 | [diff] [blame] | 334 | i = str.find('\n', i) |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 335 | assert i >= 0 |
| 336 | continue |
| 337 | |
| 338 | assert ch == '\\' |
| 339 | assert i < n |
| 340 | if str[i] == '\n': |
| 341 | lno = lno + 1 |
| 342 | if i+1 == n: |
| 343 | continuation = C_BACKSLASH |
| 344 | i = i+1 |
| 345 | |
| 346 | # The last stmt may be continued for all 3 reasons. |
| 347 | # String continuation takes precedence over bracket |
| 348 | # continuation, which beats backslash continuation. |
Kurt B. Kaiser | b61602c | 2005-11-15 07:20:06 +0000 | [diff] [blame] | 349 | if (continuation != C_STRING_FIRST_LINE |
| 350 | and continuation != C_STRING_NEXT_LINES and level > 0): |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 351 | continuation = C_BRACKET |
| 352 | self.continuation = continuation |
| 353 | |
| 354 | # Push the final line number as a sentinel value, regardless of |
| 355 | # whether it's continued. |
| 356 | assert (continuation == C_NONE) == (goodlines[-1] == lno) |
| 357 | if goodlines[-1] != lno: |
| 358 | push_good(lno) |
| 359 | |
| 360 | def get_continuation_type(self): |
| 361 | self._study1() |
| 362 | return self.continuation |
| 363 | |
| 364 | # study1 was sufficient to determine the continuation status, |
| 365 | # but doing more requires looking at every character. study2 |
| 366 | # does this for the last interesting statement in the block. |
| 367 | # Creates: |
| 368 | # self.stmt_start, stmt_end |
| 369 | # slice indices of last interesting stmt |
Kurt B. Kaiser | b175445 | 2005-11-18 22:05:48 +0000 | [diff] [blame] | 370 | # self.stmt_bracketing |
| 371 | # the bracketing structure of the last interesting stmt; |
| 372 | # for example, for the statement "say(boo) or die", stmt_bracketing |
| 373 | # will be [(0, 0), (3, 1), (8, 0)]. Strings and comments are |
| 374 | # treated as brackets, for the matter. |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 375 | # self.lastch |
| 376 | # last non-whitespace character before optional trailing |
| 377 | # comment |
| 378 | # self.lastopenbracketpos |
| 379 | # if continuation is C_BRACKET, index of last open bracket |
| 380 | |
Kurt B. Kaiser | 254eb53 | 2002-09-17 03:55:13 +0000 | [diff] [blame] | 381 | def _study2(self): |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 382 | if self.study_level >= 2: |
| 383 | return |
| 384 | self._study1() |
| 385 | self.study_level = 2 |
| 386 | |
| 387 | # Set p and q to slice indices of last interesting stmt. |
| 388 | str, goodlines = self.str, self.goodlines |
| 389 | i = len(goodlines) - 1 |
| 390 | p = len(str) # index of newest line |
| 391 | while i: |
| 392 | assert p |
| 393 | # p is the index of the stmt at line number goodlines[i]. |
| 394 | # Move p back to the stmt at line number goodlines[i-1]. |
| 395 | q = p |
| 396 | for nothing in range(goodlines[i-1], goodlines[i]): |
| 397 | # tricky: sets p to 0 if no preceding newline |
Kurt B. Kaiser | 254eb53 | 2002-09-17 03:55:13 +0000 | [diff] [blame] | 398 | p = str.rfind('\n', 0, p-1) + 1 |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 399 | # The stmt str[p:q] isn't a continuation, but may be blank |
| 400 | # or a non-indenting comment line. |
| 401 | if _junkre(str, p): |
| 402 | i = i-1 |
| 403 | else: |
| 404 | break |
| 405 | if i == 0: |
| 406 | # nothing but junk! |
| 407 | assert p == 0 |
| 408 | q = p |
| 409 | self.stmt_start, self.stmt_end = p, q |
| 410 | |
| 411 | # Analyze this stmt, to find the last open bracket (if any) |
| 412 | # and last interesting character (if any). |
| 413 | lastch = "" |
| 414 | stack = [] # stack of open bracket indices |
| 415 | push_stack = stack.append |
Kurt B. Kaiser | b175445 | 2005-11-18 22:05:48 +0000 | [diff] [blame] | 416 | bracketing = [(p, 0)] |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 417 | while p < q: |
| 418 | # suck up all except ()[]{}'"#\\ |
| 419 | m = _chew_ordinaryre(str, p, q) |
| 420 | if m: |
| 421 | # we skipped at least one boring char |
Kurt B. Kaiser | 3269cc8 | 2001-07-13 20:33:46 +0000 | [diff] [blame] | 422 | newp = m.end() |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 423 | # back up over totally boring whitespace |
Kurt B. Kaiser | 3269cc8 | 2001-07-13 20:33:46 +0000 | [diff] [blame] | 424 | i = newp - 1 # index of last boring char |
| 425 | while i >= p and str[i] in " \t\n": |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 426 | i = i-1 |
Kurt B. Kaiser | 3269cc8 | 2001-07-13 20:33:46 +0000 | [diff] [blame] | 427 | if i >= p: |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 428 | lastch = str[i] |
Kurt B. Kaiser | 3269cc8 | 2001-07-13 20:33:46 +0000 | [diff] [blame] | 429 | p = newp |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 430 | if p >= q: |
| 431 | break |
| 432 | |
| 433 | ch = str[p] |
| 434 | |
| 435 | if ch in "([{": |
| 436 | push_stack(p) |
Kurt B. Kaiser | b175445 | 2005-11-18 22:05:48 +0000 | [diff] [blame] | 437 | bracketing.append((p, len(stack))) |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 438 | lastch = ch |
| 439 | p = p+1 |
| 440 | continue |
| 441 | |
| 442 | if ch in ")]}": |
| 443 | if stack: |
| 444 | del stack[-1] |
| 445 | lastch = ch |
| 446 | p = p+1 |
Kurt B. Kaiser | b175445 | 2005-11-18 22:05:48 +0000 | [diff] [blame] | 447 | bracketing.append((p, len(stack))) |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 448 | continue |
| 449 | |
| 450 | if ch == '"' or ch == "'": |
| 451 | # consume string |
| 452 | # Note that study1 did this with a Python loop, but |
| 453 | # we use a regexp here; the reason is speed in both |
| 454 | # cases; the string may be huge, but study1 pre-squashed |
| 455 | # strings to a couple of characters per line. study1 |
| 456 | # also needed to keep track of newlines, and we don't |
| 457 | # have to. |
Kurt B. Kaiser | b175445 | 2005-11-18 22:05:48 +0000 | [diff] [blame] | 458 | bracketing.append((p, len(stack)+1)) |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 459 | lastch = ch |
| 460 | p = _match_stringre(str, p, q).end() |
Kurt B. Kaiser | b175445 | 2005-11-18 22:05:48 +0000 | [diff] [blame] | 461 | bracketing.append((p, len(stack))) |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 462 | continue |
| 463 | |
| 464 | if ch == '#': |
| 465 | # consume comment and trailing newline |
Kurt B. Kaiser | b175445 | 2005-11-18 22:05:48 +0000 | [diff] [blame] | 466 | bracketing.append((p, len(stack)+1)) |
Kurt B. Kaiser | 254eb53 | 2002-09-17 03:55:13 +0000 | [diff] [blame] | 467 | p = str.find('\n', p, q) + 1 |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 468 | assert p > 0 |
Kurt B. Kaiser | b175445 | 2005-11-18 22:05:48 +0000 | [diff] [blame] | 469 | bracketing.append((p, len(stack))) |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 470 | continue |
| 471 | |
| 472 | assert ch == '\\' |
| 473 | p = p+1 # beyond backslash |
| 474 | assert p < q |
| 475 | if str[p] != '\n': |
| 476 | # the program is invalid, but can't complain |
| 477 | lastch = ch + str[p] |
| 478 | p = p+1 # beyond escaped char |
| 479 | |
| 480 | # end while p < q: |
| 481 | |
| 482 | self.lastch = lastch |
| 483 | if stack: |
| 484 | self.lastopenbracketpos = stack[-1] |
Kurt B. Kaiser | b175445 | 2005-11-18 22:05:48 +0000 | [diff] [blame] | 485 | self.stmt_bracketing = tuple(bracketing) |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 486 | |
| 487 | # Assuming continuation is C_BRACKET, return the number |
| 488 | # of spaces the next line should be indented. |
| 489 | |
Kurt B. Kaiser | 254eb53 | 2002-09-17 03:55:13 +0000 | [diff] [blame] | 490 | def compute_bracket_indent(self): |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 491 | self._study2() |
| 492 | assert self.continuation == C_BRACKET |
| 493 | j = self.lastopenbracketpos |
| 494 | str = self.str |
| 495 | n = len(str) |
Kurt B. Kaiser | 254eb53 | 2002-09-17 03:55:13 +0000 | [diff] [blame] | 496 | origi = i = str.rfind('\n', 0, j) + 1 |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 497 | j = j+1 # one beyond open bracket |
| 498 | # find first list item; set i to start of its line |
| 499 | while j < n: |
| 500 | m = _itemre(str, j) |
| 501 | if m: |
| 502 | j = m.end() - 1 # index of first interesting char |
| 503 | extra = 0 |
| 504 | break |
| 505 | else: |
| 506 | # this line is junk; advance to next line |
Kurt B. Kaiser | 254eb53 | 2002-09-17 03:55:13 +0000 | [diff] [blame] | 507 | i = j = str.find('\n', j) + 1 |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 508 | else: |
| 509 | # nothing interesting follows the bracket; |
| 510 | # reproduce the bracket line's indentation + a level |
| 511 | j = i = origi |
| 512 | while str[j] in " \t": |
| 513 | j = j+1 |
| 514 | extra = self.indentwidth |
Kurt B. Kaiser | 254eb53 | 2002-09-17 03:55:13 +0000 | [diff] [blame] | 515 | return len(str[i:j].expandtabs(self.tabwidth)) + extra |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 516 | |
| 517 | # Return number of physical lines in last stmt (whether or not |
| 518 | # it's an interesting stmt! this is intended to be called when |
| 519 | # continuation is C_BACKSLASH). |
| 520 | |
| 521 | def get_num_lines_in_stmt(self): |
| 522 | self._study1() |
| 523 | goodlines = self.goodlines |
| 524 | return goodlines[-1] - goodlines[-2] |
| 525 | |
| 526 | # Assuming continuation is C_BACKSLASH, return the number of spaces |
| 527 | # the next line should be indented. Also assuming the new line is |
| 528 | # the first one following the initial line of the stmt. |
| 529 | |
| 530 | def compute_backslash_indent(self): |
| 531 | self._study2() |
| 532 | assert self.continuation == C_BACKSLASH |
| 533 | str = self.str |
| 534 | i = self.stmt_start |
| 535 | while str[i] in " \t": |
| 536 | i = i+1 |
| 537 | startpos = i |
| 538 | |
| 539 | # See whether the initial line starts an assignment stmt; i.e., |
| 540 | # look for an = operator |
Kurt B. Kaiser | 254eb53 | 2002-09-17 03:55:13 +0000 | [diff] [blame] | 541 | endpos = str.find('\n', startpos) + 1 |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 542 | found = level = 0 |
| 543 | while i < endpos: |
| 544 | ch = str[i] |
| 545 | if ch in "([{": |
| 546 | level = level + 1 |
| 547 | i = i+1 |
| 548 | elif ch in ")]}": |
| 549 | if level: |
| 550 | level = level - 1 |
| 551 | i = i+1 |
| 552 | elif ch == '"' or ch == "'": |
| 553 | i = _match_stringre(str, i, endpos).end() |
| 554 | elif ch == '#': |
| 555 | break |
| 556 | elif level == 0 and ch == '=' and \ |
| 557 | (i == 0 or str[i-1] not in "=<>!") and \ |
| 558 | str[i+1] != '=': |
| 559 | found = 1 |
| 560 | break |
| 561 | else: |
| 562 | i = i+1 |
| 563 | |
| 564 | if found: |
| 565 | # found a legit =, but it may be the last interesting |
| 566 | # thing on the line |
| 567 | i = i+1 # move beyond the = |
| 568 | found = re.match(r"\s*\\", str[i:endpos]) is None |
| 569 | |
| 570 | if not found: |
| 571 | # oh well ... settle for moving beyond the first chunk |
| 572 | # of non-whitespace chars |
| 573 | i = startpos |
| 574 | while str[i] not in " \t\n": |
| 575 | i = i+1 |
| 576 | |
Kurt B. Kaiser | 254eb53 | 2002-09-17 03:55:13 +0000 | [diff] [blame] | 577 | return len(str[self.stmt_start:i].expandtabs(\ |
David Scherer | 7aced17 | 2000-08-15 01:13:23 +0000 | [diff] [blame] | 578 | self.tabwidth)) + 1 |
| 579 | |
| 580 | # Return the leading whitespace on the initial line of the last |
| 581 | # interesting stmt. |
| 582 | |
| 583 | def get_base_indent_string(self): |
| 584 | self._study2() |
| 585 | i, n = self.stmt_start, self.stmt_end |
| 586 | j = i |
| 587 | str = self.str |
| 588 | while j < n and str[j] in " \t": |
| 589 | j = j + 1 |
| 590 | return str[i:j] |
| 591 | |
| 592 | # Did the last interesting stmt open a block? |
| 593 | |
| 594 | def is_block_opener(self): |
| 595 | self._study2() |
| 596 | return self.lastch == ':' |
| 597 | |
| 598 | # Did the last interesting stmt close a block? |
| 599 | |
| 600 | def is_block_closer(self): |
| 601 | self._study2() |
| 602 | return _closere(self.str, self.stmt_start) is not None |
| 603 | |
| 604 | # index of last open bracket ({[, or None if none |
| 605 | lastopenbracketpos = None |
| 606 | |
| 607 | def get_last_open_bracket_pos(self): |
| 608 | self._study2() |
| 609 | return self.lastopenbracketpos |
Kurt B. Kaiser | b175445 | 2005-11-18 22:05:48 +0000 | [diff] [blame] | 610 | |
| 611 | # the structure of the bracketing of the last interesting statement, |
| 612 | # in the format defined in _study2, or None if the text didn't contain |
| 613 | # anything |
| 614 | stmt_bracketing = None |
| 615 | |
| 616 | def get_last_stmt_bracketing(self): |
| 617 | self._study2() |
| 618 | return self.stmt_bracketing |