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  1. #!/usr/bin/env python
  2. # -*- coding: utf-8 -*-
  3. """
  4. Term based tool to view **colored**, **incremental** diff in Git/Mercurial/Svn
  5. workspace, given patch or two files, or from stdin, with **side by side** and
  6. **auto pager** support. Requires python (>= 2.5.0) and ``less``.
  7. """
  8. META_INFO = {
  9. 'version' : '0.6',
  10. 'license' : 'BSD-3',
  11. 'author' : 'Matthew Wang',
  12. 'email' : 'mattwyl(@)gmail(.)com',
  13. 'url' : 'https://github.com/ymattw/cdiff',
  14. 'keywords' : 'colored incremental side-by-side diff',
  15. 'description' : ('View colored, incremental diff in workspace, given patch '
  16. 'or two files, or from stdin, with side by side and auto '
  17. 'pager support')
  18. }
  19. import sys
  20. if sys.hexversion < 0x02050000:
  21. raise SystemExit("*** Requires python >= 2.5.0")
  22. IS_PY3 = sys.hexversion >= 0x03000000
  23. import re
  24. import subprocess
  25. import errno
  26. import difflib
  27. COLORS = {
  28. 'reset' : '\x1b[0m',
  29. 'underline' : '\x1b[4m',
  30. 'reverse' : '\x1b[7m',
  31. 'red' : '\x1b[31m',
  32. 'green' : '\x1b[32m',
  33. 'yellow' : '\x1b[33m',
  34. 'blue' : '\x1b[34m',
  35. 'magenta' : '\x1b[35m',
  36. 'cyan' : '\x1b[36m',
  37. 'lightred' : '\x1b[1;31m',
  38. 'lightgreen' : '\x1b[1;32m',
  39. 'lightyellow' : '\x1b[1;33m',
  40. 'lightblue' : '\x1b[1;34m',
  41. 'lightmagenta' : '\x1b[1;35m',
  42. 'lightcyan' : '\x1b[1;36m',
  43. }
  44. # Keys for revision control probe, diff and log with diff
  45. VCS_INFO = {
  46. 'Git': {
  47. 'probe' : ['git', 'rev-parse'],
  48. 'diff' : ['git', 'diff'],
  49. 'log' : ['git', 'log', '--patch'],
  50. },
  51. 'Mercurial': {
  52. 'probe' : ['hg', 'summary'],
  53. 'diff' : ['hg', 'diff'],
  54. 'log' : ['hg', 'log', '--patch'],
  55. },
  56. 'Svn': {
  57. 'probe' : ['svn', 'info'],
  58. 'diff' : ['svn', 'diff'],
  59. 'log' : ['svn', 'log', '--diff', '--use-merge-history'],
  60. },
  61. }
  62. def colorize(text, start_color, end_color='reset'):
  63. return COLORS[start_color] + text + COLORS[end_color]
  64. class Hunk(object):
  65. def __init__(self, hunk_headers, hunk_meta, old_addr, new_addr):
  66. self._hunk_headers = hunk_headers
  67. self._hunk_meta = hunk_meta
  68. self._old_addr = old_addr # tuple (start, offset)
  69. self._new_addr = new_addr # tuple (start, offset)
  70. self._hunk_list = [] # list of tuple (attr, line)
  71. def append(self, hunk_line):
  72. """hunk_line is a 2-element tuple: (attr, text), where attr is:
  73. '-': old, '+': new, ' ': common
  74. """
  75. self._hunk_list.append(hunk_line)
  76. def mdiff(self):
  77. r"""The difflib._mdiff() function returns an interator which returns a
  78. tuple: (from line tuple, to line tuple, boolean flag)
  79. from/to line tuple -- (line num, line text)
  80. line num -- integer or None (to indicate a context separation)
  81. line text -- original line text with following markers inserted:
  82. '\0+' -- marks start of added text
  83. '\0-' -- marks start of deleted text
  84. '\0^' -- marks start of changed text
  85. '\1' -- marks end of added/deleted/changed text
  86. boolean flag -- None indicates context separation, True indicates
  87. either "from" or "to" line contains a change, otherwise False.
  88. """
  89. return difflib._mdiff(self._get_old_text(), self._get_new_text())
  90. def _get_old_text(self):
  91. out = []
  92. for (attr, line) in self._hunk_list:
  93. if attr != '+':
  94. out.append(line)
  95. return out
  96. def _get_new_text(self):
  97. out = []
  98. for (attr, line) in self._hunk_list:
  99. if attr != '-':
  100. out.append(line)
  101. return out
  102. def __iter__(self):
  103. for hunk_line in self._hunk_list:
  104. yield hunk_line
  105. class Diff(object):
  106. def __init__(self, headers, old_path, new_path, hunks):
  107. self._headers = headers
  108. self._old_path = old_path
  109. self._new_path = new_path
  110. self._hunks = hunks
  111. # Following detectors, parse_hunk_meta() and parse_hunk_line() are suppose
  112. # to be overwritten by derived class. No is_header() anymore, all
  113. # non-recognized lines are considered as headers
  114. #
  115. def is_old_path(self, line):
  116. return False
  117. def is_new_path(self, line):
  118. return False
  119. def is_hunk_meta(self, line):
  120. return False
  121. def parse_hunk_meta(self, line):
  122. """Returns a 2-element tuple, each is a tuple of (start, offset)"""
  123. return None
  124. def parse_hunk_line(self, line):
  125. """Returns a 2-element tuple: (attr, text), where attr is:
  126. '-': old, '+': new, ' ': common
  127. """
  128. return None
  129. def is_old(self, line):
  130. return False
  131. def is_new(self, line):
  132. return False
  133. def is_common(self, line):
  134. return False
  135. def is_eof(self, line):
  136. return False
  137. def markup_traditional(self):
  138. """Returns a generator"""
  139. for line in self._headers:
  140. yield self._markup_header(line)
  141. yield self._markup_old_path(self._old_path)
  142. yield self._markup_new_path(self._new_path)
  143. for hunk in self._hunks:
  144. for hunk_header in hunk._hunk_headers:
  145. yield self._markup_hunk_header(hunk_header)
  146. yield self._markup_hunk_meta(hunk._hunk_meta)
  147. for old, new, changed in hunk.mdiff():
  148. if changed:
  149. if not old[0]:
  150. # The '+' char after \x00 is kept
  151. # DEBUG: yield 'NEW: %s %s\n' % (old, new)
  152. line = new[1].strip('\x00\x01')
  153. yield self._markup_new(line)
  154. elif not new[0]:
  155. # The '-' char after \x00 is kept
  156. # DEBUG: yield 'OLD: %s %s\n' % (old, new)
  157. line = old[1].strip('\x00\x01')
  158. yield self._markup_old(line)
  159. else:
  160. # DEBUG: yield 'CHG: %s %s\n' % (old, new)
  161. yield self._markup_old('-') + \
  162. self._markup_mix(old[1], 'red')
  163. yield self._markup_new('+') + \
  164. self._markup_mix(new[1], 'green')
  165. else:
  166. yield self._markup_common(' ' + old[1])
  167. def markup_side_by_side(self, width):
  168. """Returns a generator"""
  169. wrap_char = colorize('>', 'lightmagenta')
  170. def _normalize(line):
  171. return line.replace('\t', ' '*8).replace('\n', '').replace('\r', '')
  172. def _fit_with_marker(text, markup_fn, width, pad=False):
  173. """Wrap or pad input pure text, then markup"""
  174. if len(text) > width:
  175. return markup_fn(text[:width-1]) + wrap_char
  176. elif pad:
  177. pad_len = width - len(text)
  178. return '%s%*s' % (markup_fn(text), pad_len, '')
  179. else:
  180. return markup_fn(text)
  181. def _fit_with_marker_mix(text, base_color, width, pad=False):
  182. """Wrap or pad input text which contains mdiff tags, markup at the
  183. meantime, note only left side need to set `pad`
  184. """
  185. out = [COLORS[base_color]]
  186. count = 0
  187. tag_re = re.compile(r'\x00[+^-]|\x01')
  188. while text and count < width:
  189. if text.startswith('\x00-'): # del
  190. out.append(COLORS['reverse'] + COLORS[base_color])
  191. text = text[2:]
  192. elif text.startswith('\x00+'): # add
  193. out.append(COLORS['reverse'] + COLORS[base_color])
  194. text = text[2:]
  195. elif text.startswith('\x00^'): # change
  196. out.append(COLORS['underline'] + COLORS[base_color])
  197. text = text[2:]
  198. elif text.startswith('\x01'): # reset
  199. out.append(COLORS['reset'] + COLORS[base_color])
  200. text = text[1:]
  201. else:
  202. # FIXME: utf-8 wchar might break the rule here, e.g.
  203. # u'\u554a' takes double width of a single letter, also this
  204. # depends on your terminal font. I guess audience of this
  205. # tool never put that kind of symbol in their code :-)
  206. #
  207. out.append(text[0])
  208. count += 1
  209. text = text[1:]
  210. if count == width and tag_re.sub('', text):
  211. # Was stripped: output fulfil and still has normal char in text
  212. out[-1] = COLORS['reset'] + wrap_char
  213. elif count < width and pad:
  214. pad_len = width - count
  215. out.append('%s%*s' % (COLORS['reset'], pad_len, ''))
  216. else:
  217. out.append(COLORS['reset'])
  218. return ''.join(out)
  219. # Setup line width and number width
  220. if width <= 0:
  221. width = 80
  222. (start, offset) = self._hunks[-1]._old_addr
  223. max1 = start + offset - 1
  224. (start, offset) = self._hunks[-1]._new_addr
  225. max2 = start + offset - 1
  226. num_width = max(len(str(max1)), len(str(max2)))
  227. left_num_fmt = colorize('%%(left_num)%ds' % num_width, 'yellow')
  228. right_num_fmt = colorize('%%(right_num)%ds' % num_width, 'yellow')
  229. line_fmt = left_num_fmt + ' %(left)s ' + COLORS['reset'] + \
  230. right_num_fmt + ' %(right)s\n'
  231. # yield header, old path and new path
  232. for line in self._headers:
  233. yield self._markup_header(line)
  234. yield self._markup_old_path(self._old_path)
  235. yield self._markup_new_path(self._new_path)
  236. # yield hunks
  237. for hunk in self._hunks:
  238. for hunk_header in hunk._hunk_headers:
  239. yield self._markup_hunk_header(hunk_header)
  240. yield self._markup_hunk_meta(hunk._hunk_meta)
  241. for old, new, changed in hunk.mdiff():
  242. if old[0]:
  243. left_num = str(hunk._old_addr[0] + int(old[0]) - 1)
  244. else:
  245. left_num = ' '
  246. if new[0]:
  247. right_num = str(hunk._new_addr[0] + int(new[0]) - 1)
  248. else:
  249. right_num = ' '
  250. left = _normalize(old[1])
  251. right = _normalize(new[1])
  252. if changed:
  253. if not old[0]:
  254. left = '%*s' % (width, ' ')
  255. right = right.lstrip('\x00+').rstrip('\x01')
  256. right = _fit_with_marker(right, self._markup_new, width)
  257. elif not new[0]:
  258. left = left.lstrip('\x00-').rstrip('\x01')
  259. left = _fit_with_marker(left, self._markup_old, width)
  260. right = ''
  261. else:
  262. left = _fit_with_marker_mix(left, 'red', width, 1)
  263. right = _fit_with_marker_mix(right, 'green', width)
  264. else:
  265. left = _fit_with_marker(left, self._markup_common, width, 1)
  266. right = _fit_with_marker(right, self._markup_common, width)
  267. yield line_fmt % {
  268. 'left_num': left_num,
  269. 'left': left,
  270. 'right_num': right_num,
  271. 'right': right
  272. }
  273. def _markup_header(self, line):
  274. return colorize(line, 'cyan')
  275. def _markup_old_path(self, line):
  276. return colorize(line, 'yellow')
  277. def _markup_new_path(self, line):
  278. return colorize(line, 'yellow')
  279. def _markup_hunk_header(self, line):
  280. return colorize(line, 'lightcyan')
  281. def _markup_hunk_meta(self, line):
  282. return colorize(line, 'lightblue')
  283. def _markup_common(self, line):
  284. return colorize(line, 'reset')
  285. def _markup_old(self, line):
  286. return colorize(line, 'lightred')
  287. def _markup_new(self, line):
  288. return colorize(line, 'lightgreen')
  289. def _markup_mix(self, line, base_color):
  290. del_code = COLORS['reverse'] + COLORS[base_color]
  291. add_code = COLORS['reverse'] + COLORS[base_color]
  292. chg_code = COLORS['underline'] + COLORS[base_color]
  293. rst_code = COLORS['reset'] + COLORS[base_color]
  294. line = line.replace('\x00-', del_code)
  295. line = line.replace('\x00+', add_code)
  296. line = line.replace('\x00^', chg_code)
  297. line = line.replace('\x01', rst_code)
  298. return colorize(line, base_color)
  299. class Udiff(Diff):
  300. def is_old_path(self, line):
  301. return line.startswith('--- ')
  302. def is_new_path(self, line):
  303. return line.startswith('+++ ')
  304. def is_hunk_meta(self, line):
  305. """Minimal valid hunk meta is like '@@ -1 +1 @@', note extra chars might
  306. occur after the ending @@, e.g. in git log
  307. """
  308. return (line.startswith('@@ -') and line.find(' @@') >= 8) or \
  309. (line.startswith('## -') and line.find(' ##') >= 8)
  310. def parse_hunk_meta(self, hunk_meta):
  311. # @@ -3,7 +3,6 @@
  312. a = hunk_meta.split()[1].split(',') # -3 7
  313. if len(a) > 1:
  314. old_addr = (int(a[0][1:]), int(a[1]))
  315. else:
  316. # @@ -1 +1,2 @@
  317. old_addr = (int(a[0][1:]), 0)
  318. b = hunk_meta.split()[2].split(',') # +3 6
  319. if len(b) > 1:
  320. new_addr = (int(b[0][1:]), int(b[1]))
  321. else:
  322. # @@ -0,0 +1 @@
  323. new_addr = (int(b[0][1:]), 0)
  324. return (old_addr, new_addr)
  325. def parse_hunk_line(self, line):
  326. return (line[0], line[1:])
  327. def is_old(self, line):
  328. """Exclude old path and header line from svn log --diff output, allow
  329. '----' likely to see in diff from yaml file
  330. """
  331. return line.startswith('-') and not self.is_old_path(line) and \
  332. not re.match(r'^-{5,}$', line.rstrip())
  333. def is_new(self, line):
  334. return line.startswith('+') and not self.is_new_path(line)
  335. def is_common(self, line):
  336. return line.startswith(' ')
  337. def is_eof(self, line):
  338. # \ No newline at end of file
  339. # \ No newline at end of property
  340. return line.startswith(r'\ No newline at end of')
  341. class PatchStream(object):
  342. def __init__(self, diff_hdl):
  343. self._diff_hdl = diff_hdl
  344. self._stream_header_size = 0
  345. self._stream_header = []
  346. # Test whether stream is empty by read 1 line
  347. line = self._diff_hdl.readline()
  348. if not line:
  349. self._is_empty = True
  350. else:
  351. self._stream_header.append(line)
  352. self._stream_header_size += 1
  353. self._is_empty = False
  354. def is_empty(self):
  355. return self._is_empty
  356. def read_stream_header(self, stream_header_size):
  357. """Returns a small chunk for patch type detect, suppose to call once"""
  358. for i in range(1, stream_header_size):
  359. line = self._diff_hdl.readline()
  360. if not line:
  361. break
  362. self._stream_header.append(line)
  363. self._stream_header_size += 1
  364. return self._stream_header
  365. def __iter__(self):
  366. for line in self._stream_header:
  367. yield line
  368. for line in self._diff_hdl:
  369. yield line
  370. class DiffParser(object):
  371. def __init__(self, stream):
  372. """Detect Udiff with 3 conditions, '## ' uaually indicates svn property
  373. changes in output from `svn log --diff`
  374. """
  375. self._stream = stream
  376. flag = 0
  377. for line in self._stream.read_stream_header(100):
  378. line = decode(line)
  379. if line.startswith('--- '):
  380. flag |= 1
  381. elif line.startswith('+++ '):
  382. flag |= 2
  383. elif line.startswith('@@ ') or line.startswith('## '):
  384. flag |= 4
  385. if (flag & 7) == 7:
  386. self._type = 'udiff'
  387. break
  388. else:
  389. raise RuntimeError('unknown diff type')
  390. def get_diff_generator(self):
  391. try:
  392. return self._parse()
  393. except (AssertionError, IndexError):
  394. raise RuntimeError('invalid patch format')
  395. def _parse(self):
  396. """parse all diff lines, construct a list of Diff objects"""
  397. if self._type == 'udiff':
  398. difflet = Udiff(None, None, None, None)
  399. else:
  400. raise RuntimeError('unsupported diff format')
  401. diff = Diff([], None, None, [])
  402. headers = []
  403. for line in self._stream:
  404. line = decode(line)
  405. if difflet.is_old_path(line):
  406. # FIXME: '--- ' breaks here, need to probe next 3 lines
  407. if diff._old_path and diff._new_path and len(diff._hunks) > 0:
  408. # One diff constructed
  409. yield diff
  410. diff = Diff([], None, None, [])
  411. diff = Diff(headers, line, None, [])
  412. headers = []
  413. elif difflet.is_new_path(line):
  414. diff._new_path = line
  415. elif difflet.is_hunk_meta(line):
  416. hunk_meta = line
  417. old_addr, new_addr = difflet.parse_hunk_meta(hunk_meta)
  418. hunk = Hunk(headers, hunk_meta, old_addr, new_addr)
  419. headers = []
  420. diff._hunks.append(hunk)
  421. elif len(diff._hunks) > 0 and (difflet.is_old(line) or \
  422. difflet.is_new(line) or difflet.is_common(line)):
  423. diff._hunks[-1].append(difflet.parse_hunk_line(line))
  424. elif difflet.is_eof(line):
  425. # ignore
  426. pass
  427. else:
  428. # All other non-recognized lines are considered as headers or
  429. # hunk headers respectively
  430. #
  431. headers.append(line)
  432. if headers:
  433. raise RuntimeError('dangling header(s):\n%s' % ''.join(headers))
  434. # Validate and yield the last patch set
  435. assert diff._old_path is not None
  436. assert diff._new_path is not None
  437. assert len(diff._hunks) > 0
  438. assert len(diff._hunks[-1]._hunk_meta) > 0
  439. yield diff
  440. class DiffMarkup(object):
  441. def __init__(self, stream):
  442. self._diffs = DiffParser(stream).get_diff_generator()
  443. def markup(self, side_by_side=False, width=0):
  444. """Returns a generator"""
  445. if side_by_side:
  446. return self._markup_side_by_side(width)
  447. else:
  448. return self._markup_traditional()
  449. def _markup_traditional(self):
  450. for diff in self._diffs:
  451. for line in diff.markup_traditional():
  452. yield line
  453. def _markup_side_by_side(self, width):
  454. for diff in self._diffs:
  455. for line in diff.markup_side_by_side(width):
  456. yield line
  457. def markup_to_pager(stream, opts):
  458. markup = DiffMarkup(stream)
  459. color_diff = markup.markup(side_by_side=opts.side_by_side,
  460. width=opts.width)
  461. # args stolen fron git source: github.com/git/git/blob/master/pager.c
  462. pager = subprocess.Popen(['less', '-FRSX'],
  463. stdin=subprocess.PIPE, stdout=sys.stdout)
  464. try:
  465. for line in color_diff:
  466. pager.stdin.write(line.encode('utf-8'))
  467. except KeyboardInterrupt:
  468. pass
  469. pager.stdin.close()
  470. pager.wait()
  471. def check_command_status(arguments):
  472. """Return True if command returns 0."""
  473. try:
  474. return subprocess.call(
  475. arguments, stdout=subprocess.PIPE, stderr=subprocess.PIPE) == 0
  476. except OSError:
  477. return False
  478. def revision_control_diff():
  479. """Return diff from revision control system."""
  480. for _, ops in VCS_INFO.items():
  481. if check_command_status(ops['probe']):
  482. return subprocess.Popen(ops['diff'], stdout=subprocess.PIPE).stdout
  483. def revision_control_log():
  484. """Return log from revision control system."""
  485. for _, ops in VCS_INFO.items():
  486. if check_command_status(ops['probe']):
  487. return subprocess.Popen(ops['log'], stdout=subprocess.PIPE).stdout
  488. def decode(line):
  489. """Decode UTF-8 if necessary."""
  490. try:
  491. return line.decode('utf-8')
  492. except AttributeError:
  493. return line
  494. def main():
  495. import optparse
  496. supported_vcs = sorted(VCS_INFO.keys())
  497. usage = """
  498. %prog [options]
  499. %prog [options] <patch>
  500. %prog [options] <file1> <file2>"""
  501. parser = optparse.OptionParser(usage=usage,
  502. description=META_INFO['description'],
  503. version='%%prog %s' % META_INFO['version'])
  504. parser.add_option('-s', '--side-by-side', action='store_true',
  505. help='show in side-by-side mode')
  506. parser.add_option('-w', '--width', type='int', default=80, metavar='N',
  507. help='set text width (side-by-side mode only), default is 80')
  508. parser.add_option('-l', '--log', action='store_true',
  509. help='show diff log from revision control')
  510. parser.add_option('-c', '--color', default='auto', metavar='X',
  511. help='colorize mode "auto" (default), "always", or "never"')
  512. opts, args = parser.parse_args()
  513. if opts.log:
  514. diff_hdl = revision_control_log()
  515. if not diff_hdl:
  516. sys.stderr.write(('*** Not in a supported workspace, supported '
  517. 'are: %s\n') % ', '.join(supported_vcs))
  518. return 1
  519. elif len(args) > 2:
  520. parser.print_help()
  521. return 1
  522. elif len(args) == 2:
  523. diff_hdl = subprocess.Popen(['diff', '-u', args[0], args[1]],
  524. stdout=subprocess.PIPE).stdout
  525. elif len(args) == 1:
  526. if IS_PY3:
  527. # Python3 needs the newline='' to keep '\r' (DOS format)
  528. diff_hdl = open(args[0], mode='rt', newline='')
  529. else:
  530. diff_hdl = open(args[0], mode='rt')
  531. elif sys.stdin.isatty():
  532. diff_hdl = revision_control_diff()
  533. if not diff_hdl:
  534. sys.stderr.write(('*** Not in a supported workspace, supported '
  535. 'are: %s\n\n') % ', '.join(supported_vcs))
  536. parser.print_help()
  537. return 1
  538. else:
  539. diff_hdl = sys.stdin
  540. stream = PatchStream(diff_hdl)
  541. # Don't let empty diff pass thru
  542. if stream.is_empty():
  543. return 0
  544. if opts.color == 'always' or (opts.color == 'auto' and sys.stdout.isatty()):
  545. try:
  546. markup_to_pager(stream, opts)
  547. except IOError:
  548. e = sys.exc_info()[1]
  549. if e.errno == errno.EPIPE:
  550. pass
  551. else:
  552. # pipe out stream untouched to make sure it is still a patch
  553. for line in stream:
  554. sys.stdout.write(decode(line))
  555. if diff_hdl is not sys.stdin:
  556. diff_hdl.close()
  557. return 0
  558. if __name__ == '__main__':
  559. sys.exit(main())
  560. # vim:set et sts=4 sw=4 tw=80: