[PATCH 1 of 2 V2] lfs: add a local store method for opening a blob

[Matt Harbison]

On Fri, 05 Jan 2018 08:20:44 -0500, Yuya Nishihara <yuya at tcha.org> wrote:

> On Fri, 5 Jan 2018 08:04:54 -0500, Matt Harbison wrote:
>>
>> > On Jan 5, 2018, at 1:10 AM, Yuya Nishihara <yuya at tcha.org> wrote:
>> >
>> >> On Thu, 04 Jan 2018 21:59:09 -0500, Matt Harbison wrote:
>> >> # HG changeset patch
>> >> # User Matt Harbison <matt_harbison at yahoo.com>
>> >> # Date 1514945910 18000
>> >> #      Tue Jan 02 21:18:30 2018 -0500
>> >> # Node ID b8a794103bbb0506069f2b0ad101ba6b0455dc26
>> >> # Parent  31fe397f2bdab5fea4752947e70549e7a7d04f75
>> >> lfs: add a local store method for opening a blob
>> >>
>> >> The has() and read() methods already dynamically switch between the  
>> usercache
>> >> and local store.  This should generally be preferred to directly  
>> accessing the
>> >> vfs instances outside of the store.
>> >>
>> >> The file is now explicitly opened in binary mode for clarity.  (It  
>> was also
>> >> being opened in binary mode before, but only because vfs.__call__()  
>> appends 'b'
>> >> if needed when not opening with 'text=True'.)
>> >>
>> >> diff --git a/hgext/lfs/blobstore.py b/hgext/lfs/blobstore.py
>> >> --- a/hgext/lfs/blobstore.py
>> >> +++ b/hgext/lfs/blobstore.py
>> >> @@ -100,6 +100,14 @@
>> >>         self.cachevfs = lfsvfs(usercache)
>> >>         self.ui = repo.ui
>> >>
>> >> +    def open(self, oid):
>> >> +        """Open a read-only file descriptor to the named blob, in  
>> either the
>> >> +        usercache or the local store."""
>> >> +        if self.cachevfs.exists(oid):
>> >> +            return self.cachevfs(oid, 'rb')
>> >> +
>> >> +        return self.vfs(oid, 'rb')
>> >
>> > Oops, one more nit. cachevfs vs vfs, which should precede the other?  
>> I think
>> > vfs is more "near" as it must belong to the same filesystem.
>>
>> The only reason I ordered it like that was so if the file doesn’t exist  
>> in either place, the “abort: no such file” message points to the local  
>> repo, not somewhere in ~/ or some other place.
>>
>> It’s hard to say what’s more likely to be populated. I’ve been hitting  
>> a lot of cases lately where it is only in vfscache, but that’s because  
>> I’m working with multiple clones. However, the blob will also be in  
>> vfscache because of commits if there’s only one clone, so that seems  
>> like the most likely place to be populated?
>
> Can you add inline comments? I'm already getting confused with lfs, but  
> we're
> responsible for making lfs less bad than largefiles. :)

Lol.  Will do.

Which parts are confusing?  (I've been a little confused by some things  
too, but I'm wondering how much overlap there is, what can be clarified,  
and how much is me juggling too many projects at once.)