mercurial-scm/hg-stable: mercurial/parser.py annotate

annotate mercurial/parser.py @ 25654:af329a84310c

parser: accept iterator of tokens instead of tokenizer function and program This can simplify the interface of parse() function. Our tokenizer tends to have optional arguments other than the message to be parsed. Before this patch, the "lookup" argument existed only for the revset, and the templater had to pack [program, start, end] to be passed to its tokenizer.

author	Yuya Nishihara <yuya@tcha.org>
date	Sun, 21 Jun 2015 00:49:26 +0900
parents	c87b05925054
children	b8b73652c1c9

rev	line source
11274 77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	1 # parser.py - simple top-down operator precedence parser for mercurial
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	2 #
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	3 # Copyright 2010 Matt Mackall <mpm@selenic.com>
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	4 #
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	5 # This software may be used and distributed according to the terms of the
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	6 # GNU General Public License version 2 or any later version.
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	7
11449 05af334bac05 parser: fix URL to effbot Julian Cowley <julian@lava.net> parents: 11412 diff changeset	8 # see http://effbot.org/zone/simple-top-down-parsing.htm and
11274 77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	9 # http://eli.thegreenplace.net/2010/01/02/top-down-operator-precedence-parsing/
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	10 # for background
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	11
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	12 # takes a tokenizer and elements
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	13 # tokenizer is an iterator that returns type, value pairs
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	14 # elements is a mapping of types to binding strength, prefix and infix actions
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	15 # an action is a tree node name, a tree label, and an optional match
17500 8ac8db8dc346 en-us: labeled timeless@mozdev.org parents: 14701 diff changeset	16 # __call__(program) parses program into a labeled tree
11274 77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	17
11289 4215ce511134 revset: raise ParseError exceptions Matt Mackall <mpm@selenic.com> parents: 11278 diff changeset	18 import error
14701 4b93bd041772 parsers: fix localization markup of parser errors Mads Kiilerich <mads@kiilerich.com> parents: 13665 diff changeset	19 from i18n import _
11289 4215ce511134 revset: raise ParseError exceptions Matt Mackall <mpm@selenic.com> parents: 11278 diff changeset	20
11274 77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	21 class parser(object):
25654 af329a84310c parser: accept iterator of tokens instead of tokenizer function and program Yuya Nishihara <yuya@tcha.org> parents: 25306 diff changeset	22 def __init__(self, elements, methods=None):
11274 77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	23 self._elements = elements
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	24 self._methods = methods
13176 895f54a79c6e templater: use the parser.py parser to extend the templater syntax Matt Mackall <mpm@selenic.com> parents: 11449 diff changeset	25 self.current = None
11274 77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	26 def _advance(self):
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	27 'advance the tokenizer'
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	28 t = self.current
25171 d647f97f88dd parsers: use 'next' instead of try/except Pierre-Yves David <pierre-yves.david@fb.com> parents: 20778 diff changeset	29 self.current = next(self._iter, None)
11274 77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	30 return t
11319 9d1cf337a78d parser: fix missing param in _match Peter Arrenbrecht <peter.arrenbrecht@gmail.com> parents: 11305 diff changeset	31 def _match(self, m, pos):
11274 77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	32 'make sure the tokenizer matches an end condition'
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	33 if self.current[0] != m:
14701 4b93bd041772 parsers: fix localization markup of parser errors Mads Kiilerich <mads@kiilerich.com> parents: 13665 diff changeset	34 raise error.ParseError(_("unexpected token: %s") % self.current[0],
11305 d4cafcb63f77 cleanups: undefined variables Dirkjan Ochtman <dirkjan@ochtman.nl> parents: 11289 diff changeset	35 self.current[2])
11274 77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	36 self._advance()
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	37 def _parse(self, bind=0):
11289 4215ce511134 revset: raise ParseError exceptions Matt Mackall <mpm@selenic.com> parents: 11278 diff changeset	38 token, value, pos = self._advance()
11274 77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	39 # handle prefix rules on current token
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	40 prefix = self._elements[token][1]
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	41 if not prefix:
14701 4b93bd041772 parsers: fix localization markup of parser errors Mads Kiilerich <mads@kiilerich.com> parents: 13665 diff changeset	42 raise error.ParseError(_("not a prefix: %s") % token, pos)
11274 77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	43 if len(prefix) == 1:
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	44 expr = (prefix[0], value)
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	45 else:
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	46 if len(prefix) > 2 and prefix[2] == self.current[0]:
11319 9d1cf337a78d parser: fix missing param in _match Peter Arrenbrecht <peter.arrenbrecht@gmail.com> parents: 11305 diff changeset	47 self._match(prefix[2], pos)
11274 77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	48 expr = (prefix[0], None)
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	49 else:
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	50 expr = (prefix[0], self._parse(prefix[1]))
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	51 if len(prefix) > 2:
11319 9d1cf337a78d parser: fix missing param in _match Peter Arrenbrecht <peter.arrenbrecht@gmail.com> parents: 11305 diff changeset	52 self._match(prefix[2], pos)
11274 77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	53 # gather tokens until we meet a lower binding strength
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	54 while bind < self._elements[self.current[0]][0]:
11289 4215ce511134 revset: raise ParseError exceptions Matt Mackall <mpm@selenic.com> parents: 11278 diff changeset	55 token, value, pos = self._advance()
11278 7df88cdf47fd revset: add support for prefix and suffix versions of : and :: Matt Mackall <mpm@selenic.com> parents: 11274 diff changeset	56 e = self._elements[token]
7df88cdf47fd revset: add support for prefix and suffix versions of : and :: Matt Mackall <mpm@selenic.com> parents: 11274 diff changeset	57 # check for suffix - next token isn't a valid prefix
7df88cdf47fd revset: add support for prefix and suffix versions of : and :: Matt Mackall <mpm@selenic.com> parents: 11274 diff changeset	58 if len(e) == 4 and not self._elements[self.current[0]][1]:
7df88cdf47fd revset: add support for prefix and suffix versions of : and :: Matt Mackall <mpm@selenic.com> parents: 11274 diff changeset	59 suffix = e[3]
7df88cdf47fd revset: add support for prefix and suffix versions of : and :: Matt Mackall <mpm@selenic.com> parents: 11274 diff changeset	60 expr = (suffix[0], expr)
11274 77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	61 else:
11278 7df88cdf47fd revset: add support for prefix and suffix versions of : and :: Matt Mackall <mpm@selenic.com> parents: 11274 diff changeset	62 # handle infix rules
11412 51ceb1571805 parser: improve infix error checking Matt Mackall <mpm@selenic.com> parents: 11319 diff changeset	63 if len(e) < 3 or not e[2]:
14701 4b93bd041772 parsers: fix localization markup of parser errors Mads Kiilerich <mads@kiilerich.com> parents: 13665 diff changeset	64 raise error.ParseError(_("not an infix: %s") % token, pos)
11412 51ceb1571805 parser: improve infix error checking Matt Mackall <mpm@selenic.com> parents: 11319 diff changeset	65 infix = e[2]
11278 7df88cdf47fd revset: add support for prefix and suffix versions of : and :: Matt Mackall <mpm@selenic.com> parents: 11274 diff changeset	66 if len(infix) == 3 and infix[2] == self.current[0]:
11319 9d1cf337a78d parser: fix missing param in _match Peter Arrenbrecht <peter.arrenbrecht@gmail.com> parents: 11305 diff changeset	67 self._match(infix[2], pos)
11278 7df88cdf47fd revset: add support for prefix and suffix versions of : and :: Matt Mackall <mpm@selenic.com> parents: 11274 diff changeset	68 expr = (infix[0], expr, (None))
7df88cdf47fd revset: add support for prefix and suffix versions of : and :: Matt Mackall <mpm@selenic.com> parents: 11274 diff changeset	69 else:
7df88cdf47fd revset: add support for prefix and suffix versions of : and :: Matt Mackall <mpm@selenic.com> parents: 11274 diff changeset	70 expr = (infix[0], expr, self._parse(infix[1]))
7df88cdf47fd revset: add support for prefix and suffix versions of : and :: Matt Mackall <mpm@selenic.com> parents: 11274 diff changeset	71 if len(infix) == 3:
11319 9d1cf337a78d parser: fix missing param in _match Peter Arrenbrecht <peter.arrenbrecht@gmail.com> parents: 11305 diff changeset	72 self._match(infix[2], pos)
11274 77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	73 return expr
25654 af329a84310c parser: accept iterator of tokens instead of tokenizer function and program Yuya Nishihara <yuya@tcha.org> parents: 25306 diff changeset	74 def parse(self, tokeniter):
af329a84310c parser: accept iterator of tokens instead of tokenizer function and program Yuya Nishihara <yuya@tcha.org> parents: 25306 diff changeset	75 'generate a parse tree from tokens'
af329a84310c parser: accept iterator of tokens instead of tokenizer function and program Yuya Nishihara <yuya@tcha.org> parents: 25306 diff changeset	76 self._iter = tokeniter
13176 895f54a79c6e templater: use the parser.py parser to extend the templater syntax Matt Mackall <mpm@selenic.com> parents: 11449 diff changeset	77 self._advance()
13665 e798e430c5e5 revset: report a parse error if a revset is not parsed completely (issue2654) Bernhard Leiner <bleiner@gmail.com> parents: 13176 diff changeset	78 res = self._parse()
e798e430c5e5 revset: report a parse error if a revset is not parsed completely (issue2654) Bernhard Leiner <bleiner@gmail.com> parents: 13176 diff changeset	79 token, value, pos = self.current
e798e430c5e5 revset: report a parse error if a revset is not parsed completely (issue2654) Bernhard Leiner <bleiner@gmail.com> parents: 13176 diff changeset	80 return res, pos
11274 77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	81 def eval(self, tree):
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	82 'recursively evaluate a parse tree using node methods'
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	83 if not isinstance(tree, tuple):
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	84 return tree
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	85 return self._methods[tree[0]](*[self.eval(t) for t in tree[1:]])
25654 af329a84310c parser: accept iterator of tokens instead of tokenizer function and program Yuya Nishihara <yuya@tcha.org> parents: 25306 diff changeset	86 def __call__(self, tokeniter):
af329a84310c parser: accept iterator of tokens instead of tokenizer function and program Yuya Nishihara <yuya@tcha.org> parents: 25306 diff changeset	87 'parse tokens into a parse tree and evaluate if methods given'
af329a84310c parser: accept iterator of tokens instead of tokenizer function and program Yuya Nishihara <yuya@tcha.org> parents: 25306 diff changeset	88 t = self.parse(tokeniter)
11274 77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	89 if self._methods:
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	90 return self.eval(t)
77272d28b53f revset: introduce basic parser Matt Mackall <mpm@selenic.com> parents: diff changeset	91 return t
25253 3f1a9b44b8c2 parser: move prettyformat() function from revset module Yuya Nishihara <yuya@tcha.org> parents: 25171 diff changeset	92
25254 060bdfef2517 parser: extract closure of prettyformat() to a top-level function Yuya Nishihara <yuya@tcha.org> parents: 25253 diff changeset	93 def _prettyformat(tree, leafnodes, level, lines):
060bdfef2517 parser: extract closure of prettyformat() to a top-level function Yuya Nishihara <yuya@tcha.org> parents: 25253 diff changeset	94 if not isinstance(tree, tuple) or tree[0] in leafnodes:
060bdfef2517 parser: extract closure of prettyformat() to a top-level function Yuya Nishihara <yuya@tcha.org> parents: 25253 diff changeset	95 lines.append((level, str(tree)))
060bdfef2517 parser: extract closure of prettyformat() to a top-level function Yuya Nishihara <yuya@tcha.org> parents: 25253 diff changeset	96 else:
060bdfef2517 parser: extract closure of prettyformat() to a top-level function Yuya Nishihara <yuya@tcha.org> parents: 25253 diff changeset	97 lines.append((level, '(%s' % tree[0]))
060bdfef2517 parser: extract closure of prettyformat() to a top-level function Yuya Nishihara <yuya@tcha.org> parents: 25253 diff changeset	98 for s in tree[1:]:
060bdfef2517 parser: extract closure of prettyformat() to a top-level function Yuya Nishihara <yuya@tcha.org> parents: 25253 diff changeset	99 _prettyformat(s, leafnodes, level + 1, lines)
060bdfef2517 parser: extract closure of prettyformat() to a top-level function Yuya Nishihara <yuya@tcha.org> parents: 25253 diff changeset	100 lines[-1:] = [(lines[-1][0], lines[-1][1] + ')')]
060bdfef2517 parser: extract closure of prettyformat() to a top-level function Yuya Nishihara <yuya@tcha.org> parents: 25253 diff changeset	101
25253 3f1a9b44b8c2 parser: move prettyformat() function from revset module Yuya Nishihara <yuya@tcha.org> parents: 25171 diff changeset	102 def prettyformat(tree, leafnodes):
3f1a9b44b8c2 parser: move prettyformat() function from revset module Yuya Nishihara <yuya@tcha.org> parents: 25171 diff changeset	103 lines = []
25254 060bdfef2517 parser: extract closure of prettyformat() to a top-level function Yuya Nishihara <yuya@tcha.org> parents: 25253 diff changeset	104 _prettyformat(tree, leafnodes, 0, lines)
25253 3f1a9b44b8c2 parser: move prettyformat() function from revset module Yuya Nishihara <yuya@tcha.org> parents: 25171 diff changeset	105 output = '\n'.join((' ' * l + s) for l, s in lines)
3f1a9b44b8c2 parser: move prettyformat() function from revset module Yuya Nishihara <yuya@tcha.org> parents: 25171 diff changeset	106 return output
25306 c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	107
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	108 def simplifyinfixops(tree, targetnodes):
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	109 """Flatten chained infix operations to reduce usage of Python stack
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	110
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	111 >>> def f(tree):
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	112 ... print prettyformat(simplifyinfixops(tree, ('or',)), ('symbol',))
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	113 >>> f(('or',
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	114 ... ('or',
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	115 ... ('symbol', '1'),
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	116 ... ('symbol', '2')),
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	117 ... ('symbol', '3')))
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	118 (or
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	119 ('symbol', '1')
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	120 ('symbol', '2')
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	121 ('symbol', '3'))
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	122 >>> f(('func',
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	123 ... ('symbol', 'p1'),
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	124 ... ('or',
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	125 ... ('or',
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	126 ... ('func',
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	127 ... ('symbol', 'sort'),
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	128 ... ('list',
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	129 ... ('or',
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	130 ... ('or',
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	131 ... ('symbol', '1'),
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	132 ... ('symbol', '2')),
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	133 ... ('symbol', '3')),
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	134 ... ('negate',
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	135 ... ('symbol', 'rev')))),
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	136 ... ('and',
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	137 ... ('symbol', '4'),
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	138 ... ('group',
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	139 ... ('or',
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	140 ... ('or',
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	141 ... ('symbol', '5'),
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	142 ... ('symbol', '6')),
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	143 ... ('symbol', '7'))))),
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	144 ... ('symbol', '8'))))
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	145 (func
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	146 ('symbol', 'p1')
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	147 (or
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	148 (func
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	149 ('symbol', 'sort')
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	150 (list
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	151 (or
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	152 ('symbol', '1')
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	153 ('symbol', '2')
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	154 ('symbol', '3'))
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	155 (negate
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	156 ('symbol', 'rev'))))
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	157 (and
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	158 ('symbol', '4')
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	159 (group
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	160 (or
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	161 ('symbol', '5')
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	162 ('symbol', '6')
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	163 ('symbol', '7'))))
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	164 ('symbol', '8')))
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	165 """
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	166 if not isinstance(tree, tuple):
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	167 return tree
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	168 op = tree[0]
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	169 if op not in targetnodes:
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	170 return (op,) + tuple(simplifyinfixops(x, targetnodes) for x in tree[1:])
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	171
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	172 # walk down left nodes taking each right node. no recursion to left nodes
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	173 # because infix operators are left-associative, i.e. left tree is deep.
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	174 # e.g. '1 + 2 + 3' -> (+ (+ 1 2) 3) -> (+ 1 2 3)
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	175 simplified = []
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	176 x = tree
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	177 while x[0] == op:
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	178 l, r = x[1:]
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	179 simplified.append(simplifyinfixops(r, targetnodes))
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	180 x = l
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	181 simplified.append(simplifyinfixops(x, targetnodes))
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	182 simplified.append(op)
c87b05925054 parser: add helper to reduce nesting of chained infix operations Yuya Nishihara <yuya@tcha.org> parents: 25254 diff changeset	183 return tuple(reversed(simplified))

Mercurial > public > mercurial-scm > hg-stable

annotate mercurial/parser.py @ 25654:af329a84310c