Mercurial > hg
view mercurial/fileset.py @ 35569:964212780daf
rust: implementation of `hg`
This commit provides a mostly-working implementation of the
`hg` script in Rust along with scaffolding to support Rust in
the repository.
If you are familiar with Rust, the contents of the added rust/
directory should be pretty straightforward. We create an "hgcli"
package that implements a binary application to run Mercurial.
The output of this package is an "hg" binary.
Our Rust `hg` (henceforth "rhg") essentially is a port of the existing
`hg` Python script. The main difference is the creation of the embedded
CPython interpreter is handled by the binary itself instead of relying
on the shebang. In that sense, rhg is more similar to the "exe wrapper"
we currently use on Windows. However, unlike the exe wrapper, rhg does
not call the `hg` Python script. Instead, it uses the CPython APIs to
import mercurial modules and call appropriate functions. The amount of
code here is surprisingly small.
It is my intent to replace the existing C-based exe wrapper with rhg.
Preferably in the next Mercurial release. This should be achievable -
at least for some Mercurial distributions. The future/timeline for
rhg on other platforms is less clear. We already ship a hg.exe on
Windows. So if we get the quirks with Rust worked out, shipping a
Rust-based hg.exe should hopefully not be too contentious.
Now onto the implementation.
We're using python27-sys and the cpython crates for talking to the
CPython API. We currently don't use too much functionality of the
cpython crate and could have probably cut it out. However, it does
provide a reasonable abstraction over unsafe {} CPython function
calls. While we still have our fair share of those, at least we're
not dealing with too much refcounting, error checking, etc. So I
think the use of the cpython crate is justified. Plus, there is
not-yet-implemented functionality that could benefit from cpython. I
see our use of this crate only increasing.
The cpython and python27-sys crates are not without their issues.
The cpython crate didn't seem to account for the embedding use case
in its design. Instead, it seems to assume that you are building
a Python extension. It is making some questionable decisions around
certain CPython APIs. For example, it insists that
PyEval_ThreadsInitialized() is called and that the Python code
likely isn't the main thread in the underlying application. It
is also missing some functionality that is important for embedded
use cases (such as exporting the path to the Python interpreter
from its build script). After spending several hours trying to
wrangle python27-sys and cpython, I gave up and forked the project
on GitHub. Our Cargo.toml tracks this fork. I'm optimistic that
the upstream project will accept our contributions and we can
eventually unfork.
There is a non-trivial amount of code in our custom Cargo build
script. Our build.rs (which is called as part of building the hgcli
crate):
* Validates that the Python interpreter that was detected by the
python27-sys crate provides a shared library (we only support
shared library linking at this time - although this restriction
could be loosened).
* Validates that the Python is built with UCS-4 support. This ensures
maximum Unicode compatibility.
* Exports variables to the crate build allowing the built crate to e.g.
find the path to the Python interpreter.
The produced rhg should be considered alpha quality. There are several
known deficiencies. Many of these are documented with inline TODOs.
Probably the biggest limitation of rhg is that it assumes it is
running from the ./rust/target/<target> directory of a source
distribution. So, rhg is currently not very practical for real-world
use. But, if you can `cargo build` it, running the binary *should*
yield a working Mercurial CLI.
In order to support using rhg with the test harness, we needed to hack
up run-tests.py so the path to Mercurial's Python files is set properly.
The change is extremely hacky and is only intended to be a stop-gap
until the test harness gains first-class support for installing rhg.
This will likely occur after we support running rhg outside the
source directory.
Despite its officially alpha quality, rhg copes extremely well with
the test harness (at least on Linux). Using
`run-tests.py --with-hg ../rust/target/debug/hg`, I only encounter
the following failures:
* test-run-tests.t -- Warnings emitted about using an unexpected
Mercurial library. This is due to the hacky nature of setting the
Python directory when run-tests.py detected rhg.
* test-devel-warnings.t -- Expected stack trace missing frame for `hg`
(This is expected since we no longer have an `hg` script!)
* test-convert.t -- Test running `$PYTHON "$BINDIR"/hg`, which obviously
assumes `hg` is a Python script.
* test-merge-tools.t -- Same assumption about `hg` being executable with
Python.
* test-http-bad-server.t -- Seeing exit code 255 instead of 1 around
line 358.
* test-blackbox.t -- Exit code 255 instead of 1.
* test-basic.t -- Exit code 255 instead of 1.
It certainly looks like we have a bug around exit code handling. I
don't think it is severe enough to hold up review and landing of this
initial implementation. Perfect is the enemy of good.
Differential Revision: https://phab.mercurial-scm.org/D1581
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Wed, 10 Jan 2018 08:53:22 -0800 |
parents | 1fb0a85fb20e |
children | 0e369eca888f |
line wrap: on
line source
# fileset.py - file set queries for mercurial # # 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 import re from .i18n import _ from . import ( error, merge, parser, pycompat, registrar, scmutil, util, ) elements = { # token-type: binding-strength, primary, prefix, infix, suffix "(": (20, None, ("group", 1, ")"), ("func", 1, ")"), 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'} 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 tree def getstring(x, err): if x and (x[0] == 'string' or x[0] == 'symbol'): return x[1] raise error.ParseError(err) def getset(mctx, x): if not x: raise error.ParseError(_("missing argument")) return methods[x[0]](mctx, *x[1:]) def stringset(mctx, x): m = mctx.matcher([x]) return [f for f in mctx.subset if m(f)] def andset(mctx, x, y): return getset(mctx.narrow(getset(mctx, x)), y) def orset(mctx, x, y): # needs optimizing xl = getset(mctx, x) yl = getset(mctx, y) return xl + [f for f in yl if f not in xl] def notset(mctx, x): s = set(getset(mctx, x)) return [r for r in mctx.subset if r not in s] def minusset(mctx, x, y): xl = getset(mctx, x) yl = set(getset(mctx, y)) return [f for f in xl if f not in yl] def listset(mctx, a, b): raise error.ParseError(_("can't use a list in this context"), hint=_('see hg help "filesets.x or y"')) # symbols are callable like: # fun(mctx, x) # with: # mctx - current matchctx instance # x - argument in tree form symbols = {} # filesets using matchctx.status() _statuscallers = set() # filesets using matchctx.existing() _existingcallers = set() predicate = registrar.filesetpredicate() @predicate('modified()', callstatus=True) def modified(mctx, x): """File that is modified according to :hg:`status`. """ # i18n: "modified" is a keyword getargs(x, 0, 0, _("modified takes no arguments")) s = set(mctx.status().modified) return [f for f in mctx.subset if f in s] @predicate('added()', callstatus=True) def added(mctx, x): """File that is added according to :hg:`status`. """ # i18n: "added" is a keyword getargs(x, 0, 0, _("added takes no arguments")) s = set(mctx.status().added) return [f for f in mctx.subset if f in s] @predicate('removed()', callstatus=True) def removed(mctx, x): """File that is removed according to :hg:`status`. """ # i18n: "removed" is a keyword getargs(x, 0, 0, _("removed takes no arguments")) s = set(mctx.status().removed) return [f for f in mctx.subset if f in s] @predicate('deleted()', callstatus=True) def deleted(mctx, x): """Alias for ``missing()``. """ # i18n: "deleted" is a keyword getargs(x, 0, 0, _("deleted takes no arguments")) s = set(mctx.status().deleted) return [f for f in mctx.subset if f in s] @predicate('missing()', callstatus=True) def missing(mctx, x): """File that is missing according to :hg:`status`. """ # i18n: "missing" is a keyword getargs(x, 0, 0, _("missing takes no arguments")) s = set(mctx.status().deleted) return [f for f in mctx.subset if f in s] @predicate('unknown()', callstatus=True) def unknown(mctx, x): """File that is unknown according to :hg:`status`. These files will only be considered if this predicate is used. """ # i18n: "unknown" is a keyword getargs(x, 0, 0, _("unknown takes no arguments")) s = set(mctx.status().unknown) return [f for f in mctx.subset if f in s] @predicate('ignored()', callstatus=True) def ignored(mctx, x): """File that is ignored according to :hg:`status`. These files will only be considered if this predicate is used. """ # i18n: "ignored" is a keyword getargs(x, 0, 0, _("ignored takes no arguments")) s = set(mctx.status().ignored) return [f for f in mctx.subset if f in s] @predicate('clean()', callstatus=True) def clean(mctx, x): """File that is clean according to :hg:`status`. """ # i18n: "clean" is a keyword getargs(x, 0, 0, _("clean takes no arguments")) s = set(mctx.status().clean) return [f for f in mctx.subset if f in s] def func(mctx, a, b): if a[0] == 'symbol' and a[1] in symbols: funcname = a[1] enabled = mctx._existingenabled mctx._existingenabled = funcname in _existingcallers try: return symbols[funcname](mctx, b) finally: mctx._existingenabled = enabled keep = lambda fn: getattr(fn, '__doc__', None) is not None syms = [s for (s, fn) in symbols.items() if keep(fn)] raise error.UnknownIdentifier(a[1], syms) def getlist(x): if not x: return [] if x[0] == 'list': return getlist(x[1]) + [x[2]] 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 @predicate('binary()', callexisting=True) def binary(mctx, x): """File that appears to be binary (contains NUL bytes). """ # i18n: "binary" is a keyword getargs(x, 0, 0, _("binary takes no arguments")) return [f for f in mctx.existing() if mctx.ctx[f].isbinary()] @predicate('exec()', callexisting=True) def exec_(mctx, x): """File that is marked as executable. """ # i18n: "exec" is a keyword getargs(x, 0, 0, _("exec takes no arguments")) return [f for f in mctx.existing() if mctx.ctx.flags(f) == 'x'] @predicate('symlink()', callexisting=True) def symlink(mctx, x): """File that is marked as a symlink. """ # i18n: "symlink" is a keyword getargs(x, 0, 0, _("symlink takes no arguments")) return [f for f in mctx.existing() if mctx.ctx.flags(f) == 'l'] @predicate('resolved()') def resolved(mctx, x): """File that is marked resolved according to :hg:`resolve -l`. """ # i18n: "resolved" is a keyword getargs(x, 0, 0, _("resolved takes no arguments")) if mctx.ctx.rev() is not None: return [] ms = merge.mergestate.read(mctx.ctx.repo()) return [f for f in mctx.subset if f in ms and ms[f] == 'r'] @predicate('unresolved()') def unresolved(mctx, x): """File that is marked unresolved according to :hg:`resolve -l`. """ # i18n: "unresolved" is a keyword getargs(x, 0, 0, _("unresolved takes no arguments")) if mctx.ctx.rev() is not None: return [] ms = merge.mergestate.read(mctx.ctx.repo()) return [f for f in mctx.subset if f in ms and ms[f] == 'u'] @predicate('hgignore()') def hgignore(mctx, x): """File that matches the active .hgignore pattern. """ # i18n: "hgignore" is a keyword getargs(x, 0, 0, _("hgignore takes no arguments")) ignore = mctx.ctx.repo().dirstate._ignore return [f for f in mctx.subset if ignore(f)] @predicate('portable()') def portable(mctx, x): """File that has a portable name. (This doesn't include filenames with case collisions.) """ # i18n: "portable" is a keyword getargs(x, 0, 0, _("portable takes no arguments")) checkwinfilename = util.checkwinfilename return [f for f in mctx.subset if checkwinfilename(f) is None] @predicate('grep(regex)', callexisting=True) def grep(mctx, x): """File contains the given regular expression. """ try: # i18n: "grep" is a keyword r = re.compile(getstring(x, _("grep requires a pattern"))) except re.error as e: raise error.ParseError(_('invalid match pattern: %s') % e) return [f for f in mctx.existing() if r.search(mctx.ctx[f].data())] def _sizetomax(s): try: s = s.strip().lower() for k, v in util._sizeunits: if s.endswith(k): # max(4k) = 5k - 1, max(4.5k) = 4.6k - 1 n = s[:-len(k)] inc = 1.0 if "." in n: inc /= 10 ** len(n.split(".")[1]) return int((float(n) + inc) * v) - 1 # no extension, this is a precise value return int(s) except ValueError: raise error.ParseError(_("couldn't parse size: %s") % s) @predicate('size(expression)', callexisting=True) def size(mctx, x): """File size matches the given expression. Examples: - size('1k') - files from 1024 to 2047 bytes - size('< 20k') - files less than 20480 bytes - size('>= .5MB') - files at least 524288 bytes - size('4k - 1MB') - files from 4096 bytes to 1048576 bytes """ # i18n: "size" is a keyword expr = getstring(x, _("size requires an expression")).strip() if '-' in expr: # do we have a range? a, b = expr.split('-', 1) a = util.sizetoint(a) b = util.sizetoint(b) m = lambda x: x >= a and x <= b elif expr.startswith("<="): a = util.sizetoint(expr[2:]) m = lambda x: x <= a elif expr.startswith("<"): a = util.sizetoint(expr[1:]) m = lambda x: x < a elif expr.startswith(">="): a = util.sizetoint(expr[2:]) m = lambda x: x >= a elif expr.startswith(">"): a = util.sizetoint(expr[1:]) m = lambda x: x > a elif expr[0].isdigit or expr[0] == '.': a = util.sizetoint(expr) b = _sizetomax(expr) m = lambda x: x >= a and x <= b else: raise error.ParseError(_("couldn't parse size: %s") % expr) return [f for f in mctx.existing() if m(mctx.ctx[f].size())] @predicate('encoding(name)', callexisting=True) def encoding(mctx, x): """File can be successfully decoded with the given character encoding. May not be useful for encodings other than ASCII and UTF-8. """ # i18n: "encoding" is a keyword enc = getstring(x, _("encoding requires an encoding name")) s = [] for f in mctx.existing(): d = mctx.ctx[f].data() try: d.decode(enc) except LookupError: raise error.Abort(_("unknown encoding '%s'") % enc) except UnicodeDecodeError: continue s.append(f) return s @predicate('eol(style)', callexisting=True) def eol(mctx, x): """File contains newlines of the given style (dos, unix, mac). Binary files are excluded, files with mixed line endings match multiple styles. """ # i18n: "eol" is a keyword enc = getstring(x, _("eol requires a style name")) s = [] for f in mctx.existing(): d = mctx.ctx[f].data() if util.binary(d): continue if (enc == 'dos' or enc == 'win') and '\r\n' in d: s.append(f) elif enc == 'unix' and re.search('(?<!\r)\n', d): s.append(f) elif enc == 'mac' and re.search('\r(?!\n)', d): s.append(f) return s @predicate('copied()') def copied(mctx, x): """File that is recorded as being copied. """ # i18n: "copied" is a keyword getargs(x, 0, 0, _("copied takes no arguments")) s = [] for f in mctx.subset: p = mctx.ctx[f].parents() if p and p[0].path() != f: s.append(f) return s @predicate('revs(revs, pattern)') def revs(mctx, x): """Evaluate set in the specified revisions. If the revset match multiple revs, this will return file matching pattern in any of the revision. """ # i18n: "revs" is a keyword r, x = getargs(x, 2, 2, _("revs takes two arguments")) # i18n: "revs" is a keyword revspec = getstring(r, _("first argument to revs must be a revision")) repo = mctx.ctx.repo() revs = scmutil.revrange(repo, [revspec]) found = set() result = [] for r in revs: ctx = repo[r] for f in getset(mctx.switch(ctx, _buildstatus(ctx, x)), x): if f not in found: found.add(f) result.append(f) return result @predicate('status(base, rev, pattern)') def status(mctx, x): """Evaluate predicate using status change between ``base`` and ``rev``. Examples: - ``status(3, 7, added())`` - matches files added from "3" to "7" """ repo = mctx.ctx.repo() # i18n: "status" is a keyword b, r, x = getargs(x, 3, 3, _("status takes three arguments")) # i18n: "status" is a keyword baseerr = _("first argument to status must be a revision") baserevspec = getstring(b, baseerr) if not baserevspec: raise error.ParseError(baseerr) reverr = _("second argument to status must be a revision") revspec = getstring(r, reverr) if not revspec: raise error.ParseError(reverr) basenode, node = scmutil.revpair(repo, [baserevspec, revspec]) basectx = repo[basenode] ctx = repo[node] return getset(mctx.switch(ctx, _buildstatus(ctx, x, basectx=basectx)), x) @predicate('subrepo([pattern])') def subrepo(mctx, x): """Subrepositories whose paths match the given pattern. """ # i18n: "subrepo" is a keyword getargs(x, 0, 1, _("subrepo takes at most one argument")) ctx = mctx.ctx sstate = sorted(ctx.substate) if x: # i18n: "subrepo" is a keyword pat = getstring(x, _("subrepo requires a pattern or no arguments")) from . import match as matchmod # avoid circular import issues fast = not matchmod.patkind(pat) if fast: def m(s): return (s == pat) else: m = matchmod.match(ctx.repo().root, '', [pat], ctx=ctx) return [sub for sub in sstate if m(sub)] else: return [sub for sub in sstate] methods = { 'string': stringset, 'symbol': stringset, 'and': andset, 'or': orset, 'minus': minusset, 'list': listset, 'group': getset, 'not': notset, 'func': func, } class matchctx(object): def __init__(self, ctx, subset, status=None): self.ctx = ctx self.subset = subset self._status = status self._existingenabled = False def status(self): return self._status def matcher(self, patterns): return self.ctx.match(patterns) def filter(self, files): return [f for f in files if f in self.subset] def existing(self): assert self._existingenabled, 'unexpected existing() invocation' if self._status is not None: removed = set(self._status[3]) unknown = set(self._status[4] + self._status[5]) else: removed = set() unknown = set() return (f for f in self.subset if (f in self.ctx and f not in removed) or f in unknown) def narrow(self, files): return matchctx(self.ctx, self.filter(files), self._status) def switch(self, ctx, status=None): subset = self.filter(_buildsubset(ctx, status)) return matchctx(ctx, subset, status) class fullmatchctx(matchctx): """A match context where any files in any revisions should be valid""" def __init__(self, ctx, status=None): subset = _buildsubset(ctx, status) super(fullmatchctx, self).__init__(ctx, subset, status) def switch(self, ctx, status=None): return fullmatchctx(ctx, status) # filesets using matchctx.switch() _switchcallers = [ 'revs', 'status', ] def _intree(funcs, tree): if isinstance(tree, tuple): if tree[0] == 'func' and tree[1][0] == 'symbol': if tree[1][1] in funcs: return True if tree[1][1] in _switchcallers: # arguments won't be evaluated in the current context return False for s in tree[1:]: if _intree(funcs, s): return True return False def _buildsubset(ctx, status): if status: subset = [] for c in status: subset.extend(c) return subset else: return list(ctx.walk(ctx.match([]))) def getfileset(ctx, expr): tree = parse(expr) return getset(fullmatchctx(ctx, _buildstatus(ctx, tree)), tree) def _buildstatus(ctx, tree, basectx=None): # do we need status info? # temporaty boolean to simplify the next conditional purewdir = ctx.rev() is None and basectx is None if (_intree(_statuscallers, tree) or # Using matchctx.existing() on a workingctx requires us to check # for deleted files. (purewdir and _intree(_existingcallers, tree))): unknown = _intree(['unknown'], tree) ignored = _intree(['ignored'], tree) r = ctx.repo() if basectx is None: basectx = ctx.p1() return r.status(basectx, ctx, unknown=unknown, ignored=ignored, clean=True) else: return None def prettyformat(tree): return parser.prettyformat(tree, ('string', 'symbol')) def loadpredicate(ui, extname, registrarobj): """Load fileset predicates from specified registrarobj """ for name, func in registrarobj._table.iteritems(): symbols[name] = func if func._callstatus: _statuscallers.add(name) if func._callexisting: _existingcallers.add(name) # load built-in predicates explicitly to setup _statuscallers/_existingcallers loadpredicate(None, None, predicate) # tell hggettext to extract docstrings from these functions: i18nfunctions = symbols.values()