Mercurial > hg
view mercurial/filesetlang.py @ 39604:335ae4d0a552
bundlerepo: dynamically create repository type from base repository
Previously, bundlerepository inherited from localrepo.localrepository.
You simply instantiated a bundlerepository and its __init__ called
localrepo.localrepository.__init__. Things were simple.
Unfortunately, this strategy is limiting because it assumes that
the base repository is a localrepository instance. And it assumes
various properties of localrepository, such as the arguments its
__init__ takes. And it prevents us from changing behavior of
localrepository.__init__ without also having to change derived classes.
Previous and ongoing work to abstract storage revealed these
limitations.
This commit changes the initialization strategy of bundle repositories
to dynamically create a type to represent the repository. Instead of
a static type, we instantiate a new local repo instance via
localrepo.instance(). We then combine its __class__ with
bundlerepository to produce a new type. This ensures that no matter
how localrepo.instance() decides to create a repository object, we
can derive a bundle repo object from it. i.e. localrepo.instance()
could return a type that isn't a localrepository and it would "just
work."
Well, it would "just work" if bundlerepository's custom implementations
only accessed attributes in the documented repository interface. I'm
pretty sure it violates the interface contract in a handful of
places. But we can worry about that another day. This change gets us
closer to doing more clever things around instantiating repository
instances without having to worry about teaching bundlerepository about
them.
.. api::
``bundlerepo.bundlerepository`` is no longer usable on its own.
The class is combined with the class of the base repository it is
associated with at run-time.
New bundlerepository instances can be obtained by calling
``bundlerepo.instance()`` or ``bundlerepo.makebundlerepository()``.
Differential Revision: https://phab.mercurial-scm.org/D4555
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Tue, 11 Sep 2018 19:50:07 -0700 |
parents | e79a69af1593 |
children | 2372284d9457 |
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# filesetlang.py - parser, tokenizer and utility for file set language # # Copyright 2010 Matt Mackall <mpm@selenic.com> # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. from __future__ import absolute_import from .i18n import _ from . import ( error, parser, pycompat, ) # common weight constants for static optimization # (see registrar.filesetpredicate for details) WEIGHT_CHECK_FILENAME = 0.5 WEIGHT_READ_CONTENTS = 30 WEIGHT_STATUS = 10 WEIGHT_STATUS_THOROUGH = 50 elements = { # token-type: binding-strength, primary, prefix, infix, suffix "(": (20, None, ("group", 1, ")"), ("func", 1, ")"), None), ":": (15, None, None, ("kindpat", 15), None), "-": (5, None, ("negate", 19), ("minus", 5), None), "not": (10, None, ("not", 10), None, None), "!": (10, None, ("not", 10), None, None), "and": (5, None, None, ("and", 5), None), "&": (5, None, None, ("and", 5), None), "or": (4, None, None, ("or", 4), None), "|": (4, None, None, ("or", 4), None), "+": (4, None, None, ("or", 4), None), ",": (2, None, None, ("list", 2), None), ")": (0, None, None, None, None), "symbol": (0, "symbol", None, None, None), "string": (0, "string", None, None, None), "end": (0, None, None, None, None), } keywords = {'and', 'or', 'not'} symbols = {} globchars = ".*{}[]?/\\_" def tokenize(program): pos, l = 0, len(program) program = pycompat.bytestr(program) while pos < l: c = program[pos] if c.isspace(): # skip inter-token whitespace pass elif c in "(),-:|&+!": # handle simple operators yield (c, None, pos) elif (c in '"\'' or c == 'r' and program[pos:pos + 2] in ("r'", 'r"')): # handle quoted strings if c == 'r': pos += 1 c = program[pos] decode = lambda x: x else: decode = parser.unescapestr pos += 1 s = pos while pos < l: # find closing quote d = program[pos] if d == '\\': # skip over escaped characters pos += 2 continue if d == c: yield ('string', decode(program[s:pos]), s) break pos += 1 else: raise error.ParseError(_("unterminated string"), s) elif c.isalnum() or c in globchars or ord(c) > 127: # gather up a symbol/keyword s = pos pos += 1 while pos < l: # find end of symbol d = program[pos] if not (d.isalnum() or d in globchars or ord(d) > 127): break pos += 1 sym = program[s:pos] if sym in keywords: # operator keywords yield (sym, None, s) else: yield ('symbol', sym, s) pos -= 1 else: raise error.ParseError(_("syntax error"), pos) pos += 1 yield ('end', None, pos) def parse(expr): p = parser.parser(elements) tree, pos = p.parse(tokenize(expr)) if pos != len(expr): raise error.ParseError(_("invalid token"), pos) return parser.simplifyinfixops(tree, {'list', 'or'}) def getsymbol(x): if x and x[0] == 'symbol': return x[1] raise error.ParseError(_('not a symbol')) def getstring(x, err): if x and (x[0] == 'string' or x[0] == 'symbol'): return x[1] raise error.ParseError(err) def getkindpat(x, y, allkinds, err): kind = getsymbol(x) pat = getstring(y, err) if kind not in allkinds: raise error.ParseError(_("invalid pattern kind: %s") % kind) return '%s:%s' % (kind, pat) def getpattern(x, allkinds, err): if x and x[0] == 'kindpat': return getkindpat(x[1], x[2], allkinds, err) return getstring(x, err) def getlist(x): if not x: return [] if x[0] == 'list': return list(x[1:]) return [x] def getargs(x, min, max, err): l = getlist(x) if len(l) < min or len(l) > max: raise error.ParseError(err) return l def _analyze(x): if x is None: return x op = x[0] if op in {'string', 'symbol'}: return x if op == 'kindpat': getsymbol(x[1]) # kind must be a symbol t = _analyze(x[2]) return (op, x[1], t) if op == 'group': return _analyze(x[1]) if op == 'negate': raise error.ParseError(_("can't use negate operator in this context")) if op == 'not': t = _analyze(x[1]) return (op, t) if op == 'and': ta = _analyze(x[1]) tb = _analyze(x[2]) return (op, ta, tb) if op == 'minus': return _analyze(('and', x[1], ('not', x[2]))) if op in {'list', 'or'}: ts = tuple(_analyze(y) for y in x[1:]) return (op,) + ts if op == 'func': getsymbol(x[1]) # function name must be a symbol ta = _analyze(x[2]) return (op, x[1], ta) raise error.ProgrammingError('invalid operator %r' % op) def _insertstatushints(x): """Insert hint nodes where status should be calculated (first path) This works in bottom-up way, summing up status names and inserting hint nodes at 'and' and 'or' as needed. Thus redundant hint nodes may be left. Returns (status-names, new-tree) at the given subtree, where status-names is a sum of status names referenced in the given subtree. """ if x is None: return (), x op = x[0] if op in {'string', 'symbol', 'kindpat'}: return (), x if op == 'not': h, t = _insertstatushints(x[1]) return h, (op, t) if op == 'and': ha, ta = _insertstatushints(x[1]) hb, tb = _insertstatushints(x[2]) hr = ha + hb if ha and hb: return hr, ('withstatus', (op, ta, tb), ('string', ' '.join(hr))) return hr, (op, ta, tb) if op == 'or': hs, ts = zip(*(_insertstatushints(y) for y in x[1:])) hr = sum(hs, ()) if sum(bool(h) for h in hs) > 1: return hr, ('withstatus', (op,) + ts, ('string', ' '.join(hr))) return hr, (op,) + ts if op == 'list': hs, ts = zip(*(_insertstatushints(y) for y in x[1:])) return sum(hs, ()), (op,) + ts if op == 'func': f = getsymbol(x[1]) # don't propagate 'ha' crossing a function boundary ha, ta = _insertstatushints(x[2]) if getattr(symbols.get(f), '_callstatus', False): return (f,), ('withstatus', (op, x[1], ta), ('string', f)) return (), (op, x[1], ta) raise error.ProgrammingError('invalid operator %r' % op) def _mergestatushints(x, instatus): """Remove redundant status hint nodes (second path) This is the top-down path to eliminate inner hint nodes. """ if x is None: return x op = x[0] if op == 'withstatus': if instatus: # drop redundant hint node return _mergestatushints(x[1], instatus) t = _mergestatushints(x[1], instatus=True) return (op, t, x[2]) if op in {'string', 'symbol', 'kindpat'}: return x if op == 'not': t = _mergestatushints(x[1], instatus) return (op, t) if op == 'and': ta = _mergestatushints(x[1], instatus) tb = _mergestatushints(x[2], instatus) return (op, ta, tb) if op in {'list', 'or'}: ts = tuple(_mergestatushints(y, instatus) for y in x[1:]) return (op,) + ts if op == 'func': # don't propagate 'instatus' crossing a function boundary ta = _mergestatushints(x[2], instatus=False) return (op, x[1], ta) raise error.ProgrammingError('invalid operator %r' % op) def analyze(x): """Transform raw parsed tree to evaluatable tree which can be fed to optimize() or getmatch() All pseudo operations should be mapped to real operations or functions defined in methods or symbols table respectively. """ t = _analyze(x) _h, t = _insertstatushints(t) return _mergestatushints(t, instatus=False) def _optimizeandops(op, ta, tb): if tb is not None and tb[0] == 'not': return ('minus', ta, tb[1]) return (op, ta, tb) def _optimizeunion(xs): # collect string patterns so they can be compiled into a single regexp ws, ts, ss = [], [], [] for x in xs: w, t = _optimize(x) if t is not None and t[0] in {'string', 'symbol', 'kindpat'}: ss.append(t) continue ws.append(w) ts.append(t) if ss: ws.append(WEIGHT_CHECK_FILENAME) ts.append(('patterns',) + tuple(ss)) return ws, ts def _optimize(x): if x is None: return 0, x op = x[0] if op == 'withstatus': w, t = _optimize(x[1]) return w, (op, t, x[2]) if op in {'string', 'symbol'}: return WEIGHT_CHECK_FILENAME, x if op == 'kindpat': w, t = _optimize(x[2]) return w, (op, x[1], t) if op == 'not': w, t = _optimize(x[1]) return w, (op, t) if op == 'and': wa, ta = _optimize(x[1]) wb, tb = _optimize(x[2]) if wa <= wb: return wa, _optimizeandops(op, ta, tb) else: return wb, _optimizeandops(op, tb, ta) if op == 'or': ws, ts = _optimizeunion(x[1:]) if len(ts) == 1: return ws[0], ts[0] # 'or' operation is fully optimized out ts = tuple(it[1] for it in sorted(enumerate(ts), key=lambda it: ws[it[0]])) return max(ws), (op,) + ts if op == 'list': ws, ts = zip(*(_optimize(y) for y in x[1:])) return sum(ws), (op,) + ts if op == 'func': f = getsymbol(x[1]) w = getattr(symbols.get(f), '_weight', 1) wa, ta = _optimize(x[2]) return w + wa, (op, x[1], ta) raise error.ProgrammingError('invalid operator %r' % op) def optimize(x): """Reorder/rewrite evaluatable tree for optimization All pseudo operations should be transformed beforehand. """ _w, t = _optimize(x) return t def prettyformat(tree): return parser.prettyformat(tree, ('string', 'symbol'))