store: replace invocation of "getsize()" by "vfs.stat()"
This patch replaces invocation of "getsize()", which calls "os.stat()"
internally, by "vfs.stat()".
The object referred by "self.rawvfs" is used internally by
"_fncachevfs" and doesn't encode filename for each file API invocation.
This patch invokes "os.stat()" via "self.rawvfs" to avoid redundant
filename encoding: invocation of "os.stat()" via "self.vfs" hides
filename encoding and encoding result from caller, so it is not
appropriate, when both encoded and non-encoded filenames should be
yield.
Even though changeset b42b0729744d improved stream_out performance by
"self.pathsep + path", this patch replaces it by
"os.path.join(self.base, path)" of vfs. So, this may increase cost to
join path components.
But this shouldn't have large impact, because:
- such cost is much less than cost of "os.stat()" which causes
system call invocation
- "datafiles()" of store object is invoked only for "hg manifest
--all" or "hg verify" which are both heavy functions
$ echo "[extensions]" >> $HGRCPATH
$ echo "mq=" >> $HGRCPATH
$ hg init
$ echo 'base' > base
$ hg ci -Ambase
adding base
$ hg qnew -mmqbase mqbase
$ hg qsave
$ hg qrestore 2
restoring status: hg patches saved state