graphlog: make functions private, fix names

graphlog: remove unused get_revs() function

localrepo: use file API via vfs while ensuring repository directory As a part of migration to vfs, this patch invokes some file API indirectly via vfs, while ensuring repository directory in the constructor of "localrepository" class. New file API are added to "scmutil.abstractopener" class, because they are also used via other derived classes than "scmutil.opener". But "join()" is not yet defined other than "scmutil.opener" class, because it should not be used via other opener classes yet.

localrepo: use "vfs" intead of "opener" while ensuring repository directory As a part of migration to vfs, this patch uses "self.vfs" instead of "self.opener", while ensuring repository directory in the constructor of "localrepository" class.

localrepo: use the path relative to "self.vfs" instead of "path" argument As a part of migration to vfs, this patch uses "self.root", which can be recognized as the path relative to "self.vfs", instead of "path" argument. This fix allows to make invocations of "util.makedirs()" and "os.path.exists()" while ensuring repository directory in "localrepository.__init__()" ones indirectly via vfs. But this fix also raises issue 2528: "hg clone" with empty destination. "path" argument is empty in many cases, so this issue can't be fixed in the view of "localrepository.__init__()". Before this patch, it is fixed by empty-ness check ("not name") of exception handler in "util.makedirs()". try: os.mkdir(name) except OSError, err: if err.errno == errno.EEXIST: return if err.errno != errno.ENOENT or not name: raise This requires "localrepository.__init__()" to invoke "util.makedirs()" with "path" instead of "self.root", because empty "path" is treated as "current directory" and "self.root" becomes valid path. But "hg clone" with empty destination can be detected also in "hg.clone()" before "localrepository.__init__()" invocation, so this patch re-fixes issue2528 by checking it in "hg.clone()".

localrepo: use "self.wvfs.join()" instead of "os.path.join()" As a part of migration to vfs, this patch uses "self.wvfs.join()" instead of "os.path.join()", while initialization of fields in the constructor of "localrepository" class.

localrepo: use path expansion API via vfs As a part of migration to vfs, this patch moves path expansion API invocations in the constructor of "localrepository" to the constructor of "opener", because the root path to the repository is very important to handle paths using non-ASCII characters correctly. This patch also rearrange initialization order of "wvfs" field, because it is required to initialize "self.root".