tests/test-strict.t

clfilter: introduce `filteredrevs` attribute on changelog

This changeset allows changelog object to be "filtered". You can assign a set of
revision numbers to the `changelog.filteredrevs` attributes. The changelog will
then pretends these revision does not exists in this repo.

A few methods need to be altered to achieve this behavior:

- tip
- __iter_
- irevs
- hasnode
- headrevs

For consistency and to help debugging, the following methods are altered too.
Tests tend to show it's not necessary to alter them but have them raise proper
exception helps to detect bad acces to filtered revisions.

- rev
- node
- linkrev
- parentrevs
- flags

The following methods would also need alteration for consistency purpose but
this is non-trivial and not done yet.

- nodemap
- strip

The C version of headrevs is not run if there is any revision to filter. It'll
need a proper rewrite later to restore performance.

  $ hg init

  $ echo a > a
  $ hg ci -Ama
  adding a

  $ hg an a
  0: a

  $ hg --config ui.strict=False an a
  0: a

  $ echo "[ui]" >> $HGRCPATH
  $ echo "strict=True" >> $HGRCPATH

  $ hg an a
  hg: unknown command 'an'
  Mercurial Distributed SCM
  
  basic commands:
  
   add           add the specified files on the next commit
   annotate      show changeset information by line for each file
   clone         make a copy of an existing repository
   commit        commit the specified files or all outstanding changes
   diff          diff repository (or selected files)
   export        dump the header and diffs for one or more changesets
   forget        forget the specified files on the next commit
   init          create a new repository in the given directory
   log           show revision history of entire repository or files
   merge         merge working directory with another revision
   phase         set or show the current phase name
   pull          pull changes from the specified source
   push          push changes to the specified destination
   remove        remove the specified files on the next commit
   serve         start stand-alone webserver
   status        show changed files in the working directory
   summary       summarize working directory state
   update        update working directory (or switch revisions)
  
  use "hg help" for the full list of commands or "hg -v" for details
  [255]
  $ hg annotate a
  0: a

should succeed - up is an alias, not an abbreviation

  $ hg up
  0 files updated, 0 files merged, 0 files removed, 0 files unresolved