view tests/test-narrow-exchange.t @ 38486:4c0683655599

namespaces: let namespaces override singlenode() definition

Some namespaces have multiple nodes per name (meaning that their
namemap() returns multiple nodes). One such namespace is the "topics"
namespace (from the evolve repo). We also have our own internal
namespace at Google (for review units) that has multiple nodes per
name. These namespaces may not want to use the default "pick highest
revnum" resolution that we currently use when resolving a name to a
single node. As an example, they may decide that `hg co <name>` should
check out a commit that's last in some sense even if an earlier commit
had just been amended and thus had a higher revnum [1]. This patch
gives the namespace the option to continue to return multiple nodes
and to override how the best node is picked. Allowing namespaces to
override that may also be useful as an optimization (it may be cheaper
for the namespace to find just that node).

I have been arguing (in D3715) for using all the nodes returned from
namemap() when resolving the symbol to a revset, so e.g. `hg log -r
stable` would resolve to *all* nodes on stable, not just the one with
the highest revnum (except that I don't actually think we should
change it for the branch namespace because of BC). Most people seem
opposed to that. If we decide not to do it, I think we can deprecate
the namemap() function in favor of the new singlenode() (I find it
weird to have namespaces, like the branch namespace, where namemap()
isn't nodemap()'s inverse). I therefore think this patch makes sense
regardless of what we decide on that issue.


 [1] Actually, even the branch namespace would have wanted to override
     singlenode() if it had supported multiple nodes. That's because
     closes branch heads are mostly ignored, so "hg co default" will
     not check out the highest-revnum node if that's a closed head.

Differential Revision: https://phab.mercurial-scm.org/D3852

  $ . "$TESTDIR/narrow-library.sh"

create full repo

  $ hg init master
  $ cd master
  $ cat >> .hg/hgrc <<EOF
  > [narrow]
  > serveellipses=True
  > EOF

  $ mkdir inside
  $ echo 1 > inside/f
  $ mkdir inside2
  $ echo 1 > inside2/f
  $ mkdir outside
  $ echo 1 > outside/f
  $ hg ci -Aqm 'initial'

  $ echo 2 > inside/f
  $ hg ci -qm 'inside 2'

  $ echo 2 > inside2/f
  $ hg ci -qm 'inside2 2'

  $ echo 2 > outside/f
  $ hg ci -qm 'outside 2'

  $ cd ..

  $ hg clone --narrow ssh://user@dummy/master narrow --include inside
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 3 changesets with 2 changes to 1 files
  new changesets *:* (glob)
  updating to branch default
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved

  $ hg clone --narrow ssh://user@dummy/master narrow2 --include inside --include inside2
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 4 changesets with 4 changes to 2 files
  new changesets *:* (glob)
  updating to branch default
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved

Can push to wider repo if change does not affect paths in wider repo that are
not also in narrower repo

  $ cd narrow
  $ echo 3 > inside/f
  $ hg ci -m 'inside 3'
  $ hg push ssh://user@dummy/narrow2
  pushing to ssh://user@dummy/narrow2
  searching for changes
  remote: adding changesets
  remote: adding manifests
  remote: adding file changes
  remote: added 1 changesets with 1 changes to 1 files

Can push to narrower repo if change affects only paths within remote's
narrow spec

  $ cd ../narrow2
  $ cat >> .hg/hgrc <<EOF
  > [narrow]
  > serveellipses=True
  > EOF
  $ hg co -r 'desc("inside 3")'
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ echo 4 > inside/f
  $ hg ci -m 'inside 4'
  $ hg push ssh://user@dummy/narrow
  pushing to ssh://user@dummy/narrow
  searching for changes
  remote: adding changesets
  remote: adding manifests
  remote: adding file changes
  remote: added 1 changesets with 1 changes to 1 files

Can push to narrow repo if change affects only paths outside remote's
narrow spec

  $ echo 3 > inside2/f
  $ hg ci -m 'inside2 3'
TODO: this should be successful
  $ hg push ssh://user@dummy/narrow
  pushing to ssh://user@dummy/narrow
  searching for changes
  remote: adding changesets
  remote: adding manifests
  remote: adding file changes
  remote: transaction abort!
  remote: rollback completed
  remote: abort: data/inside2/f.i@4a1aa07735e6: unknown parent! (reporevlogstore !)
  remote: abort: data/inside2/f/index@4a1aa07735e6: no node! (reposimplestore !)
  abort: stream ended unexpectedly (got 0 bytes, expected 4)
  [255]

Can pull from wider repo if change affects only paths outside remote's
narrow spec
  $ echo 4 > inside2/f
  $ hg ci -m 'inside2 4'
  $ hg log -G -T '{rev} {node|short} {files}\n'
  @  7 d78a96df731d inside2/f
  |
  o  6 8c26f5218962 inside2/f
  |
  o  5 ba3480e2f9de inside/f
  |
  o  4 4e5edd526618 inside/f
  |
  o  3 81e7e07b7ab0 outside/f
  |
  o  2 f3993b8c0c2b inside2/f
  |
  o  1 8cd66ca966b4 inside/f
  |
  o  0 c8057d6f53ab inside/f inside2/f outside/f
  
  $ cd ../narrow
  $ hg log -G -T '{rev} {node|short} {files}\n'
  o  4 ba3480e2f9de inside/f
  |
  @  3 4e5edd526618 inside/f
  |
  o  2 81e7e07b7ab0 outside/f
  |
  o  1 8cd66ca966b4 inside/f
  |
  o  0 c8057d6f53ab inside/f inside2/f outside/f
  
  $ hg pull ssh://user@dummy/narrow2
  pulling from ssh://user@dummy/narrow2
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 0 changes to 0 files
  new changesets d78a96df731d
  (run 'hg update' to get a working copy)

Check that the resulting history is valid in the full repo

  $ cd ../narrow2
  $ hg push ssh://user@dummy/master
  pushing to ssh://user@dummy/master
  searching for changes
  remote: adding changesets
  remote: adding manifests
  remote: adding file changes
  remote: added 4 changesets with 4 changes to 2 files
  $ cd ../master
  $ hg verify
  checking changesets
  checking manifests
  crosschecking files in changesets and manifests
  checking files
  3 files, 8 changesets, 10 total revisions

Can not push to wider repo if change affects paths in wider repo that are
not also in narrower repo
  $ cd ../master
  $ hg co -r 'desc("inside2 4")'
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ echo 5 > inside2/f
  $ hg ci -m 'inside2 5'
  $ hg log -G -T '{rev} {node|short} {files}\n'
  @  8 5970befb64ba inside2/f
  |
  o  7 d78a96df731d inside2/f
  |
  o  6 8c26f5218962 inside2/f
  |
  o  5 ba3480e2f9de inside/f
  |
  o  4 4e5edd526618 inside/f
  |
  o  3 81e7e07b7ab0 outside/f
  |
  o  2 f3993b8c0c2b inside2/f
  |
  o  1 8cd66ca966b4 inside/f
  |
  o  0 c8057d6f53ab inside/f inside2/f outside/f
  
  $ cd ../narrow
  $ hg pull
  pulling from ssh://user@dummy/master
  searching for changes
  adding changesets
  adding manifests
  adding file changes
  added 1 changesets with 0 changes to 0 files
  new changesets * (glob)
  (run 'hg update' to get a working copy)
TODO: this should tell the user that their narrow clone does not have the
necessary content to be able to push to the target
  $ hg push ssh://user@dummy/narrow2
  pushing to ssh://user@dummy/narrow2
  searching for changes
  remote: adding changesets
  remote: adding manifests
  remote: adding file changes
  remote: added 1 changesets with 0 changes to 0 files