Re: [PATCH v4 13/35] ls-refs: introduce ls-refs server command

On 03/02, Junio C Hamano wrote:

Brandon Williams [off-list ref] writes:

quoted

+ ls-refs
+---------
+
+`ls-refs` is the command used to request a reference advertisement in v2.
+Unlike the current reference advertisement, ls-refs takes in arguments
+which can be used to limit the refs sent from the server.

OK.

quoted

+Additional features not supported in the base command will be advertised
+as the value of the command in the capability advertisement in the form
+of a space separated list of features, e.g.  "<command>=<feature 1>
+<feature 2>".

Doesn't this explain the general convention that applies to any
command, not just ls-refs command?  As a part of ls-refs section,
<command> in the above explanation is always a constant "ls-refs",
right?

It is a bit unclear how <feature N> in the above description are
related to "arguments" in the following paragraph.  Do the server
that can show symref and peeled tags and that can limit the output
with ref-pattern advertise these three as supported features, i.e.

	ls-refs=symrefs peel ref-pattern

or something?  Would there a case where a "feature" does not
correspond 1:1 to an argument to the command, and if so how would
the server and the client negotiate use of such a feature?

I mention earlier in the document that the values of each capability are
to be defined by the capability itself, so I'm just documenting what the
value advertised means.  And a feature could mean a couple things and
doesn't necessarily mean it affects the arguments which can be provided,
and it definitely doesn't mean that each argument that can be provided
must be advertised as a feature.  If you look at the patch that
introduces shallow, the shallow feature adds lots of arguments that a
client can that use in its request.

quoted

+    ref-pattern <pattern>
+	When specified, only references matching one of the provided
+	patterns are displayed.  A pattern is either a valid refname
+	(e.g.  refs/heads/master), in which a ref must match the pattern
+	exactly, or a prefix of a ref followed by a single '*' wildcard
+	character (e.g. refs/heads/*), in which a ref must have a prefix
+	equal to the pattern up to the wildcard character.

I thought the recent concensus was left-anchored prefix match that
honors /-directory boundary, i.e. no explicit asterisk and just
saying "refs/heads" is enough to match "refs/heads" itself and
"refs/heads/master" but not "refs/headscarf"?

I don't think there was a consensus at the time, but in the next
revision I'll have them be prefixes instead of containing wildcards.

-- 
Brandon Williams