tests/test-url-download.t

revisions: allow "x123" to refer to nodeid prefix "123"

When resolving "123" to a revision, we try to interpret it as revnum
before we try to interpret it as a nodeid hex prefix. This can lead to
the shortest valid prefix being longer than necessary. This patch lets
us write such nodeids in a shorter form by prefixing them with "x"
instead of adding more hex digits until they're longer than the
longest decimal revnum.

On my hg repo with almost 69k revisions, turning this feature on saves
on average 0.4% on the average nodeid length. That clearly doesn't
justify this patch. However, it becomes more usefule when combined
with the earlier patches in this series that let you disambiguate
nodeid prefixes within a configured revset.

Note that we attempt to resolve symbols as nodeid prefixes after we've
exhausted all other posibilities, so this is a backwards compatible
change (only queries that would previously fail may now succeed).

I've still hidden this feature behind an experiemntal config option so
we can roll it back if needed.

Differential Revision: https://phab.mercurial-scm.org/D4041

#require serve

  $ hg init server
  $ hg serve -R server -p $HGPORT -d --pid-file=hg1.pid -E ../error.log
  $ cat hg1.pid >> $DAEMON_PIDS

Check basic fetching

  $ hg debugdownload "http://localhost:$HGPORT/?cmd=lookup&key=tip"
  1 0000000000000000000000000000000000000000
  $ hg debugdownload  -o null.txt "http://localhost:$HGPORT/?cmd=lookup&key=null"
  $ cat null.txt
  1 0000000000000000000000000000000000000000

Check the request is made from the usual Mercurial logic
(rev details, give different content if the request has a Mercurial user agent)

  $ get-with-headers.py --headeronly "localhost:$HGPORT" "rev/tip" content-type
  200 Script output follows
  content-type: text/html; charset=ascii
  $ hg debugdownload "http://localhost:$HGPORT/rev/tip"
  
  # HG changeset patch
  # User 
  # Date 0 0
  # Node ID 0000000000000000000000000000000000000000
  
  
  
  

Check other kind of compatible url

  $ hg debugdownload ./null.txt
  1 0000000000000000000000000000000000000000

Test largefile URL
------------------

  $ cat << EOF >> $HGRCPATH
  > [extensions]
  > largefiles=
  > EOF

  $ killdaemons.py
  $ rm -f error.log hg1.pid
  $ hg serve -R server -p $HGPORT -d --pid-file=hg1.pid -E error.log
  $ cat hg1.pid >> $DAEMON_PIDS

  $ hg -R server debuglfput null.txt
  a57b57b39ee4dc3da1e03526596007f480ecdbe8

  $ hg --traceback debugdownload "largefile://a57b57b39ee4dc3da1e03526596007f480ecdbe8" --config paths.default=http://localhost:$HGPORT/
  1 0000000000000000000000000000000000000000

from within a repository

  $ hg clone http://localhost:$HGPORT/ client
  no changes found
  updating to branch default
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ cd client
  $ hg path
  default = http://localhost:$HGPORT/
  $ hg debugdownload "largefile://a57b57b39ee4dc3da1e03526596007f480ecdbe8"
  1 0000000000000000000000000000000000000000
  $ cd ..