Mercurial > hg
view tests/test-verify-repo-operations.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 | 8b90367c4cf3 |
children | 2372284d9457 |
line wrap: on
line source
from __future__ import print_function, absolute_import """Fuzz testing for operations against a Mercurial repository This uses Hypothesis's stateful testing to generate random repository operations and test Mercurial using them, both to see if there are any unexpected errors and to compare different versions of it.""" import os import subprocess import sys # Only run if slow tests are allowed if subprocess.call(['python', '%s/hghave' % os.environ['TESTDIR'], 'slow']): sys.exit(80) # These tests require Hypothesis and pytz to be installed. # Running 'pip install hypothesis pytz' will achieve that. # Note: This won't work if you're running Python < 2.7. try: from hypothesis.extra.datetime import datetimes except ImportError: sys.stderr.write("skipped: hypothesis or pytz not installed" + os.linesep) sys.exit(80) # If you are running an old version of pip you may find that the enum34 # backport is not installed automatically. If so 'pip install enum34' will # fix this problem. try: import enum assert enum # Silence pyflakes except ImportError: sys.stderr.write("skipped: enum34 not installed" + os.linesep) sys.exit(80) import binascii from contextlib import contextmanager import errno import pipes import shutil import silenttestrunner import subprocess from hypothesis.errors import HypothesisException from hypothesis.stateful import ( rule, RuleBasedStateMachine, Bundle, precondition) from hypothesis import settings, note, strategies as st from hypothesis.configuration import set_hypothesis_home_dir from hypothesis.database import ExampleDatabase testdir = os.path.abspath(os.environ["TESTDIR"]) # We store Hypothesis examples here rather in the temporary test directory # so that when rerunning a failing test this always results in refinding the # previous failure. This directory is in .hgignore and should not be checked in # but is useful to have for development. set_hypothesis_home_dir(os.path.join(testdir, ".hypothesis")) runtests = os.path.join(os.environ["RUNTESTDIR"], "run-tests.py") testtmp = os.environ["TESTTMP"] assert os.path.isdir(testtmp) generatedtests = os.path.join(testdir, "hypothesis-generated") try: os.makedirs(generatedtests) except OSError: pass # We write out generated .t files to a file in order to ease debugging and to # give a starting point for turning failures Hypothesis finds into normal # tests. In order to ensure that multiple copies of this test can be run in # parallel we use atomic file create to ensure that we always get a unique # name. file_index = 0 while True: file_index += 1 savefile = os.path.join(generatedtests, "test-generated-%d.t" % ( file_index, )) try: os.close(os.open(savefile, os.O_CREAT | os.O_EXCL | os.O_WRONLY)) break except OSError as e: if e.errno != errno.EEXIST: raise assert os.path.exists(savefile) hgrc = os.path.join(".hg", "hgrc") filecharacters = ( "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789" "[]^_`;=@{}~ !#$%&'()+,-" ) files = st.text(filecharacters, min_size=1).map(lambda x: x.strip()).filter( bool).map(lambda s: s.encode('ascii')) safetext = st.text(st.characters( min_codepoint=1, max_codepoint=127, blacklist_categories=('Cc', 'Cs')), min_size=1).map( lambda s: s.encode('utf-8') ) extensions = st.sampled_from(('shelve', 'mq', 'blackbox',)) @contextmanager def acceptableerrors(*args): """Sometimes we know an operation we're about to perform might fail, and we're OK with some of the failures. In those cases this may be used as a context manager and will swallow expected failures, as identified by substrings of the error message Mercurial emits.""" try: yield except subprocess.CalledProcessError as e: if not any(a in e.output for a in args): note(e.output) raise reponames = st.text("abcdefghijklmnopqrstuvwxyz01234556789", min_size=1).map( lambda s: s.encode('ascii') ) class verifyingstatemachine(RuleBasedStateMachine): """This defines the set of acceptable operations on a Mercurial repository using Hypothesis's RuleBasedStateMachine. The general concept is that we manage multiple repositories inside a repos/ directory in our temporary test location. Some of these are freshly inited, some are clones of the others. Our current working directory is always inside one of these repositories while the tests are running. Hypothesis then performs a series of operations against these repositories, including hg commands, generating contents and editing the .hgrc file. If these operations fail in unexpected ways or behave differently in different configurations of Mercurial, the test will fail and a minimized .t test file will be written to the hypothesis-generated directory to exhibit that failure. Operations are defined as methods with @rule() decorators. See the Hypothesis documentation at http://hypothesis.readthedocs.org/en/release/stateful.html for more details.""" # A bundle is a reusable collection of previously generated data which may # be provided as arguments to future operations. repos = Bundle('repos') paths = Bundle('paths') contents = Bundle('contents') branches = Bundle('branches') committimes = Bundle('committimes') def __init__(self): super(verifyingstatemachine, self).__init__() self.repodir = os.path.join(testtmp, "repos") if os.path.exists(self.repodir): shutil.rmtree(self.repodir) os.chdir(testtmp) self.log = [] self.failed = False self.configperrepo = {} self.all_extensions = set() self.non_skippable_extensions = set() self.mkdirp("repos") self.cd("repos") self.mkdirp("repo1") self.cd("repo1") self.hg("init") def teardown(self): """On teardown we clean up after ourselves as usual, but we also do some additional testing: We generate a .t file based on our test run using run-test.py -i to get the correct output. We then test it in a number of other configurations, verifying that each passes the same test.""" super(verifyingstatemachine, self).teardown() try: shutil.rmtree(self.repodir) except OSError: pass ttest = os.linesep.join(" " + l for l in self.log) os.chdir(testtmp) path = os.path.join(testtmp, "test-generated.t") with open(path, 'w') as o: o.write(ttest + os.linesep) with open(os.devnull, "w") as devnull: rewriter = subprocess.Popen( [runtests, "--local", "-i", path], stdin=subprocess.PIPE, stdout=devnull, stderr=devnull, ) rewriter.communicate("yes") with open(path, 'r') as i: ttest = i.read() e = None if not self.failed: try: output = subprocess.check_output([ runtests, path, "--local", "--pure" ], stderr=subprocess.STDOUT) assert "Ran 1 test" in output, output for ext in ( self.all_extensions - self.non_skippable_extensions ): tf = os.path.join(testtmp, "test-generated-no-%s.t" % ( ext, )) with open(tf, 'w') as o: for l in ttest.splitlines(): if l.startswith(" $ hg"): l = l.replace( "--config %s=" % ( extensionconfigkey(ext),), "") o.write(l + os.linesep) with open(tf, 'r') as r: t = r.read() assert ext not in t, t output = subprocess.check_output([ runtests, tf, "--local", ], stderr=subprocess.STDOUT) assert "Ran 1 test" in output, output except subprocess.CalledProcessError as e: note(e.output) if self.failed or e is not None: with open(savefile, "wb") as o: o.write(ttest) if e is not None: raise e def execute_step(self, step): try: return super(verifyingstatemachine, self).execute_step(step) except (HypothesisException, KeyboardInterrupt): raise except Exception: self.failed = True raise # Section: Basic commands. def mkdirp(self, path): if os.path.exists(path): return self.log.append( "$ mkdir -p -- %s" % (pipes.quote(os.path.relpath(path)),)) os.makedirs(path) def cd(self, path): path = os.path.relpath(path) if path == ".": return os.chdir(path) self.log.append("$ cd -- %s" % (pipes.quote(path),)) def hg(self, *args): extra_flags = [] for key, value in self.config.items(): extra_flags.append("--config") extra_flags.append("%s=%s" % (key, value)) self.command("hg", *(tuple(extra_flags) + args)) def command(self, *args): self.log.append("$ " + ' '.join(map(pipes.quote, args))) subprocess.check_output(args, stderr=subprocess.STDOUT) # Section: Set up basic data # This section has no side effects but generates data that we will want # to use later. @rule( target=paths, source=st.lists(files, min_size=1).map(lambda l: os.path.join(*l))) def genpath(self, source): return source @rule( target=committimes, when=datetimes(min_year=1970, max_year=2038) | st.none()) def gentime(self, when): return when @rule( target=contents, content=st.one_of( st.binary(), st.text().map(lambda x: x.encode('utf-8')) )) def gencontent(self, content): return content @rule( target=branches, name=safetext, ) def genbranch(self, name): return name @rule(target=paths, source=paths) def lowerpath(self, source): return source.lower() @rule(target=paths, source=paths) def upperpath(self, source): return source.upper() # Section: Basic path operations @rule(path=paths, content=contents) def writecontent(self, path, content): self.unadded_changes = True if os.path.isdir(path): return parent = os.path.dirname(path) if parent: try: self.mkdirp(parent) except OSError: # It may be the case that there is a regular file that has # previously been created that has the same name as an ancestor # of the current path. This will cause mkdirp to fail with this # error. We just turn this into a no-op in that case. return with open(path, 'wb') as o: o.write(content) self.log.append(( "$ python -c 'import binascii; " "print(binascii.unhexlify(\"%s\"))' > %s") % ( binascii.hexlify(content), pipes.quote(path), )) @rule(path=paths) def addpath(self, path): if os.path.exists(path): self.hg("add", "--", path) @rule(path=paths) def forgetpath(self, path): if os.path.exists(path): with acceptableerrors( "file is already untracked", ): self.hg("forget", "--", path) @rule(s=st.none() | st.integers(0, 100)) def addremove(self, s): args = ["addremove"] if s is not None: args.extend(["-s", str(s)]) self.hg(*args) @rule(path=paths) def removepath(self, path): if os.path.exists(path): with acceptableerrors( 'file is untracked', 'file has been marked for add', 'file is modified', ): self.hg("remove", "--", path) @rule( message=safetext, amend=st.booleans(), when=committimes, addremove=st.booleans(), secret=st.booleans(), close_branch=st.booleans(), ) def maybecommit( self, message, amend, when, addremove, secret, close_branch ): command = ["commit"] errors = ["nothing changed"] if amend: errors.append("cannot amend public changesets") command.append("--amend") command.append("-m" + pipes.quote(message)) if secret: command.append("--secret") if close_branch: command.append("--close-branch") errors.append("can only close branch heads") if addremove: command.append("--addremove") if when is not None: if when.year == 1970: errors.append('negative date value') if when.year == 2038: errors.append('exceeds 32 bits') command.append("--date=%s" % ( when.strftime('%Y-%m-%d %H:%M:%S %z'),)) with acceptableerrors(*errors): self.hg(*command) # Section: Repository management @property def currentrepo(self): return os.path.basename(os.getcwd()) @property def config(self): return self.configperrepo.setdefault(self.currentrepo, {}) @rule( target=repos, source=repos, name=reponames, ) def clone(self, source, name): if not os.path.exists(os.path.join("..", name)): self.cd("..") self.hg("clone", source, name) self.cd(name) return name @rule( target=repos, name=reponames, ) def fresh(self, name): if not os.path.exists(os.path.join("..", name)): self.cd("..") self.mkdirp(name) self.cd(name) self.hg("init") return name @rule(name=repos) def switch(self, name): self.cd(os.path.join("..", name)) assert self.currentrepo == name assert os.path.exists(".hg") @rule(target=repos) def origin(self): return "repo1" @rule() def pull(self, repo=repos): with acceptableerrors( "repository default not found", "repository is unrelated", ): self.hg("pull") @rule(newbranch=st.booleans()) def push(self, newbranch): with acceptableerrors( "default repository not configured", "no changes found", ): if newbranch: self.hg("push", "--new-branch") else: with acceptableerrors( "creates new branches" ): self.hg("push") # Section: Simple side effect free "check" operations @rule() def log(self): self.hg("log") @rule() def verify(self): self.hg("verify") @rule() def diff(self): self.hg("diff", "--nodates") @rule() def status(self): self.hg("status") @rule() def export(self): self.hg("export") # Section: Branch management @rule() def checkbranch(self): self.hg("branch") @rule(branch=branches) def switchbranch(self, branch): with acceptableerrors( 'cannot use an integer as a name', 'cannot be used in a name', 'a branch of the same name already exists', 'is reserved', ): self.hg("branch", "--", branch) @rule(branch=branches, clean=st.booleans()) def update(self, branch, clean): with acceptableerrors( 'unknown revision', 'parse error', ): if clean: self.hg("update", "-C", "--", branch) else: self.hg("update", "--", branch) # Section: Extension management def hasextension(self, extension): return extensionconfigkey(extension) in self.config def commandused(self, extension): assert extension in self.all_extensions self.non_skippable_extensions.add(extension) @rule(extension=extensions) def addextension(self, extension): self.all_extensions.add(extension) self.config[extensionconfigkey(extension)] = "" @rule(extension=extensions) def removeextension(self, extension): self.config.pop(extensionconfigkey(extension), None) # Section: Commands from the shelve extension @rule() @precondition(lambda self: self.hasextension("shelve")) def shelve(self): self.commandused("shelve") with acceptableerrors("nothing changed"): self.hg("shelve") @rule() @precondition(lambda self: self.hasextension("shelve")) def unshelve(self): self.commandused("shelve") with acceptableerrors("no shelved changes to apply"): self.hg("unshelve") class writeonlydatabase(ExampleDatabase): def __init__(self, underlying): super(ExampleDatabase, self).__init__() self.underlying = underlying def fetch(self, key): return () def save(self, key, value): self.underlying.save(key, value) def delete(self, key, value): self.underlying.delete(key, value) def close(self): self.underlying.close() def extensionconfigkey(extension): return "extensions." + extension settings.register_profile( 'default', settings( timeout=300, stateful_step_count=50, max_examples=10, ) ) settings.register_profile( 'fast', settings( timeout=10, stateful_step_count=20, max_examples=5, min_satisfying_examples=1, max_shrinks=0, ) ) settings.register_profile( 'continuous', settings( timeout=-1, stateful_step_count=1000, max_examples=10 ** 8, max_iterations=10 ** 8, database=writeonlydatabase(settings.default.database) ) ) settings.load_profile(os.getenv('HYPOTHESIS_PROFILE', 'default')) verifyingtest = verifyingstatemachine.TestCase verifyingtest.settings = settings.default if __name__ == '__main__': try: silenttestrunner.main(__name__) finally: # So as to prevent proliferation of useless test files, if we never # actually wrote a failing test we clean up after ourselves and delete # the file for doing so that we owned. if os.path.exists(savefile) and os.path.getsize(savefile) == 0: os.unlink(savefile)