tests/test-subrepo-missing.t

tests: add helper script for processing doctests read from stdin

Writes stdin to a temp file and doctests it.

In the future we might want to spare the temp file and directly call into
doctest.

Also, with some tweaking it seems possible to adjust the line numbers reported
in an error report so they match the ones in the original file.

  $ 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
  committing subrepository subrepo
  $ echo b > subrepo/b
  $ hg -R subrepo ci -Am addb
  adding b
  $ hg ci -m updatedsub
  committing subrepository subrepo

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