# HG changeset patch # User Gregory Szorc # Date 2018-09-12 02:50:07 # Node ID 335ae4d0a5526e42ce3399158c14c6a4f45aa979 # Parent a8d2faeca49ef6e0485ec52fdd8e657b6137a861 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 diff --git a/mercurial/bundlerepo.py b/mercurial/bundlerepo.py --- a/mercurial/bundlerepo.py +++ b/mercurial/bundlerepo.py @@ -255,7 +255,7 @@ def _getfilestarts(cgunpacker): pass return filespos -class bundlerepository(localrepo.localrepository): +class bundlerepository(object): """A repository instance that is a union of a local repo and a bundle. Instances represent a read-only repository composed of a local repository @@ -263,25 +263,19 @@ class bundlerepository(localrepo.localre conceptually similar to the state of a repository after an ``hg unbundle`` operation. However, the contents of the bundle are never applied to the actual base repository. + + Instances constructed directly are not usable as repository objects. + Use instance() or makebundlerepository() to create instances. """ - def __init__(self, ui, repopath, bundlepath): - self._tempparent = None - try: - localrepo.localrepository.__init__(self, ui, repopath) - except error.RepoError: - self._tempparent = pycompat.mkdtemp() - localrepo.instance(ui, self._tempparent, create=True) - localrepo.localrepository.__init__(self, ui, self._tempparent) + def __init__(self, bundlepath, url, tempparent): + self._tempparent = tempparent + self._url = url + self.ui.setconfig('phases', 'publish', False, 'bundlerepo') - if repopath: - self._url = 'bundle:' + util.expandpath(repopath) + '+' + bundlepath - else: - self._url = 'bundle:' + bundlepath - self.tempfile = None f = util.posixfile(bundlepath, "rb") - bundle = exchange.readbundle(ui, f, bundlepath) + bundle = exchange.readbundle(self.ui, f, bundlepath) if isinstance(bundle, bundle2.unbundle20): self._bundlefile = bundle @@ -311,7 +305,7 @@ class bundlerepository(localrepo.localre if bundle.compressed(): f = self._writetempbundle(bundle.read, '.hg10un', header='HG10UN') - bundle = exchange.readbundle(ui, f, bundlepath, self.vfs) + bundle = exchange.readbundle(self.ui, f, bundlepath, self.vfs) self._bundlefile = bundle self._cgunpacker = bundle @@ -484,7 +478,41 @@ def instance(ui, path, create, intents=N def makebundlerepository(ui, repopath, bundlepath): """Make a bundle repository object based on repo and bundle paths.""" - return bundlerepository(ui, repopath, bundlepath) + if repopath: + url = 'bundle:%s+%s' % (util.expandpath(repopath), bundlepath) + else: + url = 'bundle:%s' % bundlepath + + # Because we can't make any guarantees about the type of the base + # repository, we can't have a static class representing the bundle + # repository. We also can't make any guarantees about how to even + # call the base repository's constructor! + # + # So, our strategy is to go through ``localrepo.instance()`` to construct + # a repo instance. Then, we dynamically create a new type derived from + # both it and our ``bundlerepository`` class which overrides some + # functionality. We then change the type of the constructed repository + # to this new type and initialize the bundle-specific bits of it. + + try: + parentrepo = localrepo.instance(ui, repopath, create=False) + tempparent = None + except error.RepoError: + tempparent = pycompat.mkdtemp() + try: + parentrepo = localrepo.instance(ui, tempparent, create=True) + except Exception: + shutil.rmtree(tempparent) + raise + + class derivedbundlerepository(bundlerepository, parentrepo.__class__): + pass + + repo = parentrepo + repo.__class__ = derivedbundlerepository + bundlerepository.__init__(repo, bundlepath, url, tempparent) + + return repo class bundletransactionmanager(object): def transaction(self):