tests/test-mq-caches.t

i18n: calculate terminal columns by width information of each characters

neither number of 'bytes' in any encoding nor 'characters' is
appropriate to calculate terminal columns for specified string.

this patch modifies MBTextWrapper for:

  - overriding '_wrap_chunks()' to make it use not built-in 'len()'
    but 'encoding.colwidth()' for columns of string

  - fixing '_cutdown()' to make it use 'encoding.colwidth()' instead
    of local, similar but incorrect implementation

this patch also modifies 'encoding.py':

  - dividing 'colwith()' into 2 pieces: one for calculation columns of
    specified UNICODE string, and another for rest part of original
    one. the former is used from MBTextWrapper in 'util.py'.

  - preventing 'colwidth()' from evaluating HGENCODINGAMBIGUOUS
    configuration per each invocation: 'unicodedata.east_asian_width'
    checking is kept intact for reducing startup cost.

  $ branches=.hg/cache/branchheads
  $ echo '[extensions]' >> $HGRCPATH
  $ echo 'mq =' >> $HGRCPATH

  $ show_branch_cache()
  > {
  >     # force cache (re)generation
  >     hg log -r does-not-exist 2> /dev/null
  >     hg log -r tip --template 'tip: {rev}\n'
  >     if [ -f $branches ]; then
  >       sort $branches
  >     else
  >       echo No branch cache
  >     fi
  >     if [ "$1" = 1 ]; then
  >       for b in foo bar; do
  >         hg log -r $b --template "branch $b: "'{rev}\n'
  >       done
  >     fi
  > }

  $ hg init a
  $ cd a
  $ hg qinit -c


mq patch on an empty repo

  $ hg qnew p1
  $ show_branch_cache
  tip: 0
  No branch cache

  $ echo > pfile
  $ hg add pfile
  $ hg qrefresh -m 'patch 1'
  $ show_branch_cache
  tip: 0
  No branch cache

some regular revisions

  $ hg qpop
  popping p1
  patch queue now empty
  $ echo foo > foo
  $ hg add foo
  $ echo foo > .hg/branch
  $ hg ci -m 'branch foo'

  $ echo bar > bar
  $ hg add bar
  $ echo bar > .hg/branch
  $ hg ci -m 'branch bar'
  $ show_branch_cache
  tip: 1
  c229711f16da3d7591f89b1b8d963b79bda22714 1
  c229711f16da3d7591f89b1b8d963b79bda22714 bar
  dc25e3827021582e979f600811852e36cbe57341 foo

add some mq patches

  $ hg qpush
  applying p1
  now at: p1
  $ show_branch_cache
  tip: 2
  c229711f16da3d7591f89b1b8d963b79bda22714 1
  c229711f16da3d7591f89b1b8d963b79bda22714 bar
  dc25e3827021582e979f600811852e36cbe57341 foo

  $ hg qnew p2
  $ echo foo > .hg/branch
  $ echo foo2 >> foo
  $ hg qrefresh -m 'patch 2'
  $ show_branch_cache 1
  tip: 3
  c229711f16da3d7591f89b1b8d963b79bda22714 1
  c229711f16da3d7591f89b1b8d963b79bda22714 bar
  dc25e3827021582e979f600811852e36cbe57341 foo
  branch foo: 3
  branch bar: 2

removing the cache

  $ rm $branches
  $ show_branch_cache 1
  tip: 3
  c229711f16da3d7591f89b1b8d963b79bda22714 1
  c229711f16da3d7591f89b1b8d963b79bda22714 bar
  dc25e3827021582e979f600811852e36cbe57341 foo
  branch foo: 3
  branch bar: 2

importing rev 1 (the cache now ends in one of the patches)

  $ hg qimport -r 1 -n p0
  $ show_branch_cache 1
  tip: 3
  c229711f16da3d7591f89b1b8d963b79bda22714 1
  c229711f16da3d7591f89b1b8d963b79bda22714 bar
  dc25e3827021582e979f600811852e36cbe57341 foo
  branch foo: 3
  branch bar: 2
  $ hg log -r qbase --template 'qbase: {rev}\n'
  qbase: 1

detect an invalid cache

  $ hg qpop -a
  popping p2
  popping p1
  popping p0
  patch queue now empty
  $ hg qpush -a
  applying p0
  applying p1
  applying p2
  now at: p2
  $ show_branch_cache
  tip: 3
  dc25e3827021582e979f600811852e36cbe57341 0
  dc25e3827021582e979f600811852e36cbe57341 foo