Mercurial > hg
view mercurial/dagparser.py @ 47072:4c041c71ec01
revlog: introduce an explicit tracking of what the revlog is about
Since the dawn of time, people have been forced to rely to lossy introspection
of the index filename to determine what the purpose and role of the revlog they
encounter is. This is hacky, error prone, inflexible, abstraction-leaky,
<insert-your-own-complaints-here>.
In f63299ee7e4d Raphaël introduced a new attribute to track this information:
`revlog_kind`. However it is initialized in an odd place and various instances
end up not having it set. In addition is only tracking some of the information
we end up having to introspect in various pieces of code.
So we add a new attribute that holds more data and is more strictly enforced.
This work is done in collaboration with Raphaël.
The `revlog_kind` one will be removed/adapted in the next changeset. We expect
to be able to clean up various existing piece of code and to simplify coming
work around the newer revlog format.
Differential Revision: https://phab.mercurial-scm.org/D10352
author | Pierre-Yves David <pierre-yves.david@octobus.net> |
---|---|
date | Tue, 06 Apr 2021 05:20:24 +0200 |
parents | 70f8c64812db |
children | 6000f5b25c9b |
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# dagparser.py - parser and generator for concise description of DAGs # # Copyright 2010 Peter Arrenbrecht <peter@arrenbrecht.ch> # # 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 import re import string from .i18n import _ from . import ( error, pycompat, ) from .utils import stringutil def parsedag(desc): '''parses a DAG from a concise textual description; generates events "+n" is a linear run of n nodes based on the current default parent "." is a single node based on the current default parent "$" resets the default parent to -1 (implied at the start); otherwise the default parent is always the last node created "<p" sets the default parent to the backref p "*p" is a fork at parent p, where p is a backref "*p1/p2/.../pn" is a merge of parents p1..pn, where the pi are backrefs "/p2/.../pn" is a merge of the preceding node and p2..pn ":name" defines a label for the preceding node; labels can be redefined "@text" emits an annotation event for text "!command" emits an action event for the current node "!!my command\n" is like "!", but to the end of the line "#...\n" is a comment up to the end of the line Whitespace between the above elements is ignored. A backref is either * a number n, which references the node curr-n, where curr is the current node, or * the name of a label you placed earlier using ":name", or * empty to denote the default parent. All string valued-elements are either strictly alphanumeric, or must be enclosed in double quotes ("..."), with "\" as escape character. Generates sequence of ('n', (id, [parentids])) for node creation ('l', (id, labelname)) for labels on nodes ('a', text) for annotations ('c', command) for actions (!) ('C', command) for line actions (!!) Examples -------- Example of a complex graph (output not shown for brevity): >>> len(list(parsedag(b""" ... ... +3 # 3 nodes in linear run ... :forkhere # a label for the last of the 3 nodes from above ... +5 # 5 more nodes on one branch ... :mergethis # label again ... <forkhere # set default parent to labeled fork node ... +10 # 10 more nodes on a parallel branch ... @stable # following nodes will be annotated as "stable" ... +5 # 5 nodes in stable ... !addfile # custom command; could trigger new file in next node ... +2 # two more nodes ... /mergethis # merge last node with labeled node ... +4 # 4 more nodes descending from merge node ... ... """))) 34 Empty list: >>> list(parsedag(b"")) [] A simple linear run: >>> list(parsedag(b"+3")) [('n', (0, [-1])), ('n', (1, [0])), ('n', (2, [1]))] Some non-standard ways to define such runs: >>> list(parsedag(b"+1+2")) [('n', (0, [-1])), ('n', (1, [0])), ('n', (2, [1]))] >>> list(parsedag(b"+1*1*")) [('n', (0, [-1])), ('n', (1, [0])), ('n', (2, [1]))] >>> list(parsedag(b"*")) [('n', (0, [-1]))] >>> list(parsedag(b"...")) [('n', (0, [-1])), ('n', (1, [0])), ('n', (2, [1]))] A fork and a join, using numeric back references: >>> list(parsedag(b"+2*2*/2")) [('n', (0, [-1])), ('n', (1, [0])), ('n', (2, [0])), ('n', (3, [2, 1]))] >>> list(parsedag(b"+2<2+1/2")) [('n', (0, [-1])), ('n', (1, [0])), ('n', (2, [0])), ('n', (3, [2, 1]))] Placing a label: >>> list(parsedag(b"+1 :mylabel +1")) [('n', (0, [-1])), ('l', (0, 'mylabel')), ('n', (1, [0]))] An empty label (silly, really): >>> list(parsedag(b"+1:+1")) [('n', (0, [-1])), ('l', (0, '')), ('n', (1, [0]))] Fork and join, but with labels instead of numeric back references: >>> list(parsedag(b"+1:f +1:p2 *f */p2")) [('n', (0, [-1])), ('l', (0, 'f')), ('n', (1, [0])), ('l', (1, 'p2')), ('n', (2, [0])), ('n', (3, [2, 1]))] >>> list(parsedag(b"+1:f +1:p2 <f +1 /p2")) [('n', (0, [-1])), ('l', (0, 'f')), ('n', (1, [0])), ('l', (1, 'p2')), ('n', (2, [0])), ('n', (3, [2, 1]))] Restarting from the root: >>> list(parsedag(b"+1 $ +1")) [('n', (0, [-1])), ('n', (1, [-1]))] Annotations, which are meant to introduce sticky state for subsequent nodes: >>> list(parsedag(b"+1 @ann +1")) [('n', (0, [-1])), ('a', 'ann'), ('n', (1, [0]))] >>> list(parsedag(b'+1 @"my annotation" +1')) [('n', (0, [-1])), ('a', 'my annotation'), ('n', (1, [0]))] Commands, which are meant to operate on the most recently created node: >>> list(parsedag(b"+1 !cmd +1")) [('n', (0, [-1])), ('c', 'cmd'), ('n', (1, [0]))] >>> list(parsedag(b'+1 !"my command" +1')) [('n', (0, [-1])), ('c', 'my command'), ('n', (1, [0]))] >>> list(parsedag(b'+1 !!my command line\\n +1')) [('n', (0, [-1])), ('C', 'my command line'), ('n', (1, [0]))] Comments, which extend to the end of the line: >>> list(parsedag(b'+1 # comment\\n+1')) [('n', (0, [-1])), ('n', (1, [0]))] Error: >>> try: list(parsedag(b'+1 bad')) ... except Exception as e: print(pycompat.sysstr(bytes(e))) invalid character in dag description: bad... ''' if not desc: return # pytype: disable=wrong-arg-types wordchars = pycompat.bytestr(string.ascii_letters + string.digits) # pytype: enable=wrong-arg-types labels = {} p1 = -1 r = 0 def resolve(ref): if not ref: return p1 # pytype: disable=wrong-arg-types elif ref[0] in pycompat.bytestr(string.digits): # pytype: enable=wrong-arg-types return r - int(ref) else: return labels[ref] chiter = pycompat.iterbytestr(desc) def nextch(): return next(chiter, b'\0') def nextrun(c, allow): s = b'' while c in allow: s += c c = nextch() return c, s def nextdelimited(c, limit, escape): s = b'' while c != limit: if c == escape: c = nextch() s += c c = nextch() return nextch(), s def nextstring(c): if c == b'"': return nextdelimited(nextch(), b'"', b'\\') else: return nextrun(c, wordchars) c = nextch() while c != b'\0': # pytype: disable=wrong-arg-types while c in pycompat.bytestr(string.whitespace): # pytype: enable=wrong-arg-types c = nextch() if c == b'.': yield b'n', (r, [p1]) p1 = r r += 1 c = nextch() elif c == b'+': # pytype: disable=wrong-arg-types c, digs = nextrun(nextch(), pycompat.bytestr(string.digits)) # pytype: enable=wrong-arg-types n = int(digs) for i in pycompat.xrange(0, n): yield b'n', (r, [p1]) p1 = r r += 1 elif c in b'*/': if c == b'*': c = nextch() c, pref = nextstring(c) prefs = [pref] while c == b'/': c, pref = nextstring(nextch()) prefs.append(pref) ps = [resolve(ref) for ref in prefs] yield b'n', (r, ps) p1 = r r += 1 elif c == b'<': c, ref = nextstring(nextch()) p1 = resolve(ref) elif c == b':': c, name = nextstring(nextch()) labels[name] = p1 yield b'l', (p1, name) elif c == b'@': c, text = nextstring(nextch()) yield b'a', text elif c == b'!': c = nextch() if c == b'!': cmd = b'' c = nextch() while c not in b'\n\r\0': cmd += c c = nextch() yield b'C', cmd else: c, cmd = nextstring(c) yield b'c', cmd elif c == b'#': while c not in b'\n\r\0': c = nextch() elif c == b'$': p1 = -1 c = nextch() elif c == b'\0': return # in case it was preceded by whitespace else: s = b'' i = 0 while c != b'\0' and i < 10: s += c i += 1 c = nextch() raise error.Abort( _(b'invalid character in dag description: %s...') % s ) def dagtextlines( events, addspaces=True, wraplabels=False, wrapannotations=False, wrapcommands=False, wrapnonlinear=False, usedots=False, maxlinewidth=70, ): '''generates single lines for dagtext()''' def wrapstring(text): if re.match(b"^[0-9a-z]*$", text): return text return b'"' + text.replace(b'\\', b'\\\\').replace(b'"', b'\"') + b'"' def gen(): labels = {} run = 0 wantr = 0 needroot = False for kind, data in events: if kind == b'n': r, ps = data # sanity check if r != wantr: raise error.Abort(_(b"expected id %i, got %i") % (wantr, r)) if not ps: ps = [-1] else: for p in ps: if p >= r: raise error.Abort( _( b"parent id %i is larger than " b"current id %i" ) % (p, r) ) wantr += 1 # new root? p1 = r - 1 if len(ps) == 1 and ps[0] == -1: if needroot: if run: yield b'+%d' % run run = 0 if wrapnonlinear: yield b'\n' yield b'$' p1 = -1 else: needroot = True if len(ps) == 1 and ps[0] == p1: if usedots: yield b"." else: run += 1 else: if run: yield b'+%d' % run run = 0 if wrapnonlinear: yield b'\n' prefs = [] for p in ps: if p == p1: prefs.append(b'') elif p in labels: prefs.append(labels[p]) else: prefs.append(b'%d' % (r - p)) yield b'*' + b'/'.join(prefs) else: if run: yield b'+%d' % run run = 0 if kind == b'l': rid, name = data labels[rid] = name yield b':' + name if wraplabels: yield b'\n' elif kind == b'c': yield b'!' + wrapstring(data) if wrapcommands: yield b'\n' elif kind == b'C': yield b'!!' + data yield b'\n' elif kind == b'a': if wrapannotations: yield b'\n' yield b'@' + wrapstring(data) elif kind == b'#': yield b'#' + data yield b'\n' else: raise error.Abort( _(b"invalid event type in dag: ('%s', '%s')") % ( stringutil.escapestr(kind), stringutil.escapestr(data), ) ) if run: yield b'+%d' % run line = b'' for part in gen(): if part == b'\n': if line: yield line line = b'' else: if len(line) + len(part) >= maxlinewidth: yield line line = b'' elif addspaces and line and part != b'.': line += b' ' line += part if line: yield line def dagtext( dag, addspaces=True, wraplabels=False, wrapannotations=False, wrapcommands=False, wrapnonlinear=False, usedots=False, maxlinewidth=70, ): """generates lines of a textual representation for a dag event stream events should generate what parsedag() does, so: ('n', (id, [parentids])) for node creation ('l', (id, labelname)) for labels on nodes ('a', text) for annotations ('c', text) for commands ('C', text) for line commands ('!!') ('#', text) for comment lines Parent nodes must come before child nodes. Examples -------- Linear run: >>> dagtext([(b'n', (0, [-1])), (b'n', (1, [0]))]) '+2' Two roots: >>> dagtext([(b'n', (0, [-1])), (b'n', (1, [-1]))]) '+1 $ +1' Fork and join: >>> dagtext([(b'n', (0, [-1])), (b'n', (1, [0])), (b'n', (2, [0])), ... (b'n', (3, [2, 1]))]) '+2 *2 */2' Fork and join with labels: >>> dagtext([(b'n', (0, [-1])), (b'l', (0, b'f')), (b'n', (1, [0])), ... (b'l', (1, b'p2')), (b'n', (2, [0])), (b'n', (3, [2, 1]))]) '+1 :f +1 :p2 *f */p2' Annotations: >>> dagtext([(b'n', (0, [-1])), (b'a', b'ann'), (b'n', (1, [0]))]) '+1 @ann +1' >>> dagtext([(b'n', (0, [-1])), ... (b'a', b'my annotation'), ... (b'n', (1, [0]))]) '+1 @"my annotation" +1' Commands: >>> dagtext([(b'n', (0, [-1])), (b'c', b'cmd'), (b'n', (1, [0]))]) '+1 !cmd +1' >>> dagtext([(b'n', (0, [-1])), ... (b'c', b'my command'), ... (b'n', (1, [0]))]) '+1 !"my command" +1' >>> dagtext([(b'n', (0, [-1])), ... (b'C', b'my command line'), ... (b'n', (1, [0]))]) '+1 !!my command line\\n+1' Comments: >>> dagtext([(b'n', (0, [-1])), (b'#', b' comment'), (b'n', (1, [0]))]) '+1 # comment\\n+1' >>> dagtext([]) '' Combining parsedag and dagtext: >>> dagtext(parsedag(b'+1 :f +1 :p2 *f */p2')) '+1 :f +1 :p2 *f */p2' """ return b"\n".join( dagtextlines( dag, addspaces, wraplabels, wrapannotations, wrapcommands, wrapnonlinear, usedots, maxlinewidth, ) )