source file: /System/Library/Frameworks/Python.framework/Versions/2.3/lib/python2.3/tokenize.py
file stats: 168 lines, 67 executed: 39.9% covered
1. """Tokenization help for Python programs. 2. 3. generate_tokens(readline) is a generator that breaks a stream of 4. text into Python tokens. It accepts a readline-like method which is called 5. repeatedly to get the next line of input (or "" for EOF). It generates 6. 5-tuples with these members: 7. 8. the token type (see token.py) 9. the token (a string) 10. the starting (row, column) indices of the token (a 2-tuple of ints) 11. the ending (row, column) indices of the token (a 2-tuple of ints) 12. the original line (string) 13. 14. It is designed to match the working of the Python tokenizer exactly, except 15. that it produces COMMENT tokens for comments and gives type OP for all 16. operators 17. 18. Older entry points 19. tokenize_loop(readline, tokeneater) 20. tokenize(readline, tokeneater=printtoken) 21. are the same, except instead of generating tokens, tokeneater is a callback 22. function to which the 5 fields described above are passed as 5 arguments, 23. each time a new token is found.""" 24. 25. __author__ = 'Ka-Ping Yee <ping@lfw.org>' 26. __credits__ = \ 27. 'GvR, ESR, Tim Peters, Thomas Wouters, Fred Drake, Skip Montanaro' 28. 29. import string, re 30. from token import * 31. 32. import token 33. __all__ = [x for x in dir(token) if x[0] != '_'] + ["COMMENT", "tokenize", 34. "generate_tokens", "NL"] 35. del x 36. del token 37. 38. COMMENT = N_TOKENS 39. tok_name[COMMENT] = 'COMMENT' 40. NL = N_TOKENS + 1 41. tok_name[NL] = 'NL' 42. N_TOKENS += 2 43. 44. def group(*choices): return '(' + '|'.join(choices) + ')' 45. def any(*choices): return group(*choices) + '*' 46. def maybe(*choices): return group(*choices) + '?' 47. 48. Whitespace = r'[ \f\t]*' 49. Comment = r'#[^\r\n]*' 50. Ignore = Whitespace + any(r'\\\r?\n' + Whitespace) + maybe(Comment) 51. Name = r'[a-zA-Z_]\w*' 52. 53. Hexnumber = r'0[xX][\da-fA-F]*[lL]?' 54. Octnumber = r'0[0-7]*[lL]?' 55. Decnumber = r'[1-9]\d*[lL]?' 56. Intnumber = group(Hexnumber, Octnumber, Decnumber) 57. Exponent = r'[eE][-+]?\d+' 58. Pointfloat = group(r'\d+\.\d*', r'\.\d+') + maybe(Exponent) 59. Expfloat = r'\d+' + Exponent 60. Floatnumber = group(Pointfloat, Expfloat) 61. Imagnumber = group(r'\d+[jJ]', Floatnumber + r'[jJ]') 62. Number = group(Imagnumber, Floatnumber, Intnumber) 63. 64. # Tail end of ' string. 65. Single = r"[^'\\]*(?:\\.[^'\\]*)*'" 66. # Tail end of " string. 67. Double = r'[^"\\]*(?:\\.[^"\\]*)*"' 68. # Tail end of ''' string. 69. Single3 = r"[^'\\]*(?:(?:\\.|'(?!''))[^'\\]*)*'''" 70. # Tail end of """ string. 71. Double3 = r'[^"\\]*(?:(?:\\.|"(?!""))[^"\\]*)*"""' 72. Triple = group("[uU]?[rR]?'''", '[uU]?[rR]?"""') 73. # Single-line ' or " string. 74. String = group(r"[uU]?[rR]?'[^\n'\\]*(?:\\.[^\n'\\]*)*'", 75. r'[uU]?[rR]?"[^\n"\\]*(?:\\.[^\n"\\]*)*"') 76. 77. # Because of leftmost-then-longest match semantics, be sure to put the 78. # longest operators first (e.g., if = came before ==, == would get 79. # recognized as two instances of =). 80. Operator = group(r"\*\*=?", r">>=?", r"<<=?", r"<>", r"!=", 81. r"//=?", 82. r"[+\-*/%&|^=<>]=?", 83. r"~") 84. 85. Bracket = '[][(){}]' 86. Special = group(r'\r?\n', r'[:;.,`]') 87. Funny = group(Operator, Bracket, Special) 88. 89. PlainToken = group(Number, Funny, String, Name) 90. Token = Ignore + PlainToken 91. 92. # First (or only) line of ' or " string. 93. ContStr = group(r"[uU]?[rR]?'[^\n'\\]*(?:\\.[^\n'\\]*)*" + 94. group("'", r'\\\r?\n'), 95. r'[uU]?[rR]?"[^\n"\\]*(?:\\.[^\n"\\]*)*' + 96. group('"', r'\\\r?\n')) 97. PseudoExtras = group(r'\\\r?\n', Comment, Triple) 98. PseudoToken = Whitespace + group(PseudoExtras, Number, Funny, ContStr, Name) 99. 100. tokenprog, pseudoprog, single3prog, double3prog = map( 101. re.compile, (Token, PseudoToken, Single3, Double3)) 102. endprogs = {"'": re.compile(Single), '"': re.compile(Double), 103. "'''": single3prog, '"""': double3prog, 104. "r'''": single3prog, 'r"""': double3prog, 105. "u'''": single3prog, 'u"""': double3prog, 106. "ur'''": single3prog, 'ur"""': double3prog, 107. "R'''": single3prog, 'R"""': double3prog, 108. "U'''": single3prog, 'U"""': double3prog, 109. "uR'''": single3prog, 'uR"""': double3prog, 110. "Ur'''": single3prog, 'Ur"""': double3prog, 111. "UR'''": single3prog, 'UR"""': double3prog, 112. 'r': None, 'R': None, 'u': None, 'U': None} 113. 114. triple_quoted = {} 115. for t in ("'''", '"""', 116. "r'''", 'r"""', "R'''", 'R"""', 117. "u'''", 'u"""', "U'''", 'U"""', 118. "ur'''", 'ur"""', "Ur'''", 'Ur"""', 119. "uR'''", 'uR"""', "UR'''", 'UR"""'): 120. triple_quoted[t] = t 121. single_quoted = {} 122. for t in ("'", '"', 123. "r'", 'r"', "R'", 'R"', 124. "u'", 'u"', "U'", 'U"', 125. "ur'", 'ur"', "Ur'", 'Ur"', 126. "uR'", 'uR"', "UR'", 'UR"' ): 127. single_quoted[t] = t 128. 129. tabsize = 8 130. 131. class TokenError(Exception): pass 132. 133. class StopTokenizing(Exception): pass 134. 135. def printtoken(type, token, (srow, scol), (erow, ecol), line): # for testing 136. print "%d,%d-%d,%d:\t%s\t%s" % \ 137. (srow, scol, erow, ecol, tok_name[type], repr(token)) 138. 139. def tokenize(readline, tokeneater=printtoken): 140. """ 141. The tokenize() function accepts two parameters: one representing the 142. input stream, and one providing an output mechanism for tokenize(). 143. 144. The first parameter, readline, must be a callable object which provides 145. the same interface as the readline() method of built-in file objects. 146. Each call to the function should return one line of input as a string. 147. 148. The second parameter, tokeneater, must also be a callable object. It is 149. called once for each token, with five arguments, corresponding to the 150. tuples generated by generate_tokens(). 151. """ 152. try: 153. tokenize_loop(readline, tokeneater) 154. except StopTokenizing: 155. pass 156. 157. # backwards compatible interface 158. def tokenize_loop(readline, tokeneater): 159. for token_info in generate_tokens(readline): 160. tokeneater(*token_info) 161. 162. def generate_tokens(readline): 163. """ 164. The generate_tokens() generator requires one argment, readline, which 165. must be a callable object which provides the same interface as the 166. readline() method of built-in file objects. Each call to the function 167. should return one line of input as a string. 168. 169. The generator produces 5-tuples with these members: the token type; the 170. token string; a 2-tuple (srow, scol) of ints specifying the row and 171. column where the token begins in the source; a 2-tuple (erow, ecol) of 172. ints specifying the row and column where the token ends in the source; 173. and the line on which the token was found. The line passed is the 174. logical line; continuation lines are included. 175. """ 176. lnum = parenlev = continued = 0 177. namechars, numchars = string.ascii_letters + '_', '0123456789' 178. contstr, needcont = '', 0 179. contline = None 180. indents = [0] 181. 182. while 1: # loop over lines in stream 183. line = readline() 184. lnum = lnum + 1 185. pos, max = 0, len(line) 186. 187. if contstr: # continued string 188. if not line: 189. raise TokenError, ("EOF in multi-line string", strstart) 190. endmatch = endprog.match(line) 191. if endmatch: 192. pos = end = endmatch.end(0) 193. yield (STRING, contstr + line[:end], 194. strstart, (lnum, end), contline + line) 195. contstr, needcont = '', 0 196. contline = None 197. elif needcont and line[-2:] != '\\\n' and line[-3:] != '\\\r\n': 198. yield (ERRORTOKEN, contstr + line, 199. strstart, (lnum, len(line)), contline) 200. contstr = '' 201. contline = None 202. continue 203. else: 204. contstr = contstr + line 205. contline = contline + line 206. continue 207. 208. elif parenlev == 0 and not continued: # new statement 209. if not line: break 210. column = 0 211. while pos < max: # measure leading whitespace 212. if line[pos] == ' ': column = column + 1 213. elif line[pos] == '\t': column = (column/tabsize + 1)*tabsize 214. elif line[pos] == '\f': column = 0 215. else: break 216. pos = pos + 1 217. if pos == max: break 218. 219. if line[pos] in '#\r\n': # skip comments or blank lines 220. yield ((NL, COMMENT)[line[pos] == '#'], line[pos:], 221. (lnum, pos), (lnum, len(line)), line) 222. continue 223. 224. if column > indents[-1]: # count indents or dedents 225. indents.append(column) 226. yield (INDENT, line[:pos], (lnum, 0), (lnum, pos), line) 227. while column < indents[-1]: 228. indents = indents[:-1] 229. yield (DEDENT, '', (lnum, pos), (lnum, pos), line) 230. 231. else: # continued statement 232. if not line: 233. raise TokenError, ("EOF in multi-line statement", (lnum, 0)) 234. continued = 0 235. 236. while pos < max: 237. pseudomatch = pseudoprog.match(line, pos) 238. if pseudomatch: # scan for tokens 239. start, end = pseudomatch.span(1) 240. spos, epos, pos = (lnum, start), (lnum, end), end 241. token, initial = line[start:end], line[start] 242. 243. if initial in numchars or \ 244. (initial == '.' and token != '.'): # ordinary number 245. yield (NUMBER, token, spos, epos, line) 246. elif initial in '\r\n': 247. yield (parenlev > 0 and NL or NEWLINE, 248. token, spos, epos, line) 249. elif initial == '#': 250. yield (COMMENT, token, spos, epos, line) 251. elif token in triple_quoted: 252. endprog = endprogs[token] 253. endmatch = endprog.match(line, pos) 254. if endmatch: # all on one line 255. pos = endmatch.end(0) 256. token = line[start:pos] 257. yield (STRING, token, spos, (lnum, pos), line) 258. else: 259. strstart = (lnum, start) # multiple lines 260. contstr = line[start:] 261. contline = line 262. break 263. elif initial in single_quoted or \ 264. token[:2] in single_quoted or \ 265. token[:3] in single_quoted: 266. if token[-1] == '\n': # continued string 267. strstart = (lnum, start) 268. endprog = (endprogs[initial] or endprogs[token[1]] or 269. endprogs[token[2]]) 270. contstr, needcont = line[start:], 1 271. contline = line 272. break 273. else: # ordinary string 274. yield (STRING, token, spos, epos, line) 275. elif initial in namechars: # ordinary name 276. yield (NAME, token, spos, epos, line) 277. elif initial == '\\': # continued stmt 278. continued = 1 279. else: 280. if initial in '([{': parenlev = parenlev + 1 281. elif initial in ')]}': parenlev = parenlev - 1 282. yield (OP, token, spos, epos, line) 283. else: 284. yield (ERRORTOKEN, line[pos], 285. (lnum, pos), (lnum, pos+1), line) 286. pos = pos + 1 287. 288. for indent in indents[1:]: # pop remaining indent levels 289. yield (DEDENT, '', (lnum, 0), (lnum, 0), '') 290. yield (ENDMARKER, '', (lnum, 0), (lnum, 0), '') 291. 292. if __name__ == '__main__': # testing 293. import sys 294. if len(sys.argv) > 1: tokenize(open(sys.argv[1]).readline) 295. else: tokenize(sys.stdin.readline)