view tests/test-revlog-packentry.t @ 30567:73ce055b169a

memctx: allow the metadataonlyctx thats reusing the manifest node

When we have a lot of files writing a new manifest revision can be expensive.
This commit adds a possibility for memctx to reuse a manifest from a different
commit. This can be beneficial for commands that are creating metadata changes
without any actual files changed like "hg metaedit" in evolve extension.

I will send the change for evolve that leverages this once this is accepted.

  $ hg init repo
  $ cd repo

  $ touch foo
  $ hg ci -Am 'add foo'
  adding foo

  $ hg up -C null
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved

this should be stored as a delta against rev 0

  $ echo foo bar baz > foo
  $ hg ci -Am 'add foo again'
  adding foo
  created new head

  $ hg debugindex foo
     rev    offset  length  ..... linkrev nodeid       p1           p2 (re)
       0         0       0  .....       0 b80de5d13875 000000000000 000000000000 (re)
       1         0      13  .....       1 0376abec49b8 000000000000 000000000000 (re)

  $ cd ..