tests/test-subrepo-missing.t

performance: speedup computation of mutable revisions

In their current state, revset calls can be very costly, as we test
predicates on the entire repository. The "mutable" filter is used
during branch cache loading operation. We need to make it fast.

This change drops revset calls in favor of direct testing of the
phase of a changeset.

Performance test on my Mercurial checkout
- 19857 total changesets,
- 1646 mutable revision

Before:
  ! mutable
  ! wall 0.032405

After:
  ! mutable
  ! wall 0.001469

Performance test on a Mozilla central checkout:
- 117293 total changesets,
- 1 mutable changeset,

Before:
  ! mutable
  ! wall 0.188636

After:
  ! mutable
  ! wall 0.000022

  $ hg init repo
  $ cd repo
  $ hg init subrepo
  $ echo a > subrepo/a
  $ hg -R subrepo ci -Am adda
  adding a
  $ echo 'subrepo = subrepo' > .hgsub
  $ hg ci -Am addsubrepo
  adding .hgsub
  $ echo b > subrepo/b
  $ hg -R subrepo ci -Am addb
  adding b
  $ hg ci -m updatedsub

ignore blanklines in .hgsubstate

  >>> file('.hgsubstate', 'wb').write('\n\n   \t \n   \n')
  $ hg st --subrepos
  M .hgsubstate
  $ hg revert -qC .hgsubstate

abort more gracefully on .hgsubstate parsing error

  $ cp .hgsubstate .hgsubstate.old
  >>> file('.hgsubstate', 'wb').write('\ninvalid')
  $ hg st --subrepos
  abort: invalid subrepository revision specifier in .hgsubstate line 2
  [255]
  $ mv .hgsubstate.old .hgsubstate

delete .hgsub and revert it

  $ rm .hgsub
  $ hg revert .hgsub
  warning: subrepo spec file .hgsub not found
  warning: subrepo spec file .hgsub not found

delete .hgsubstate and revert it

  $ rm .hgsubstate
  $ hg revert .hgsubstate

delete .hgsub and update

  $ rm .hgsub
  $ hg up 0
  warning: subrepo spec file .hgsub not found
  warning: subrepo spec file .hgsub not found
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg st
  warning: subrepo spec file .hgsub not found
  ! .hgsub
  $ ls subrepo
  a

delete .hgsubstate and update

  $ hg up -C
  warning: subrepo spec file .hgsub not found
  warning: subrepo spec file .hgsub not found
  2 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ rm .hgsubstate
  $ hg up 0
  remote changed .hgsubstate which local deleted
  use (c)hanged version or leave (d)eleted? c
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg st
  $ ls subrepo
  a

  $ cd ..