tests/test-mactext.t

store: encode first period or space in filenames (issue1713)

- Mac OS X has problems with filenames starting with '._'
  (e.g. '.FOO' -> '._f_o_o' is now encoded as '~2e_f_o_o')

- Explorer of Windows Vista and Windows 7 strip leading spaces of
  path elements of filenames when copying trees

Above problems are avoided by encoding the first space (as '~20') or
period (as '~2e') of all path elements.

This introduces a new entry 'dotencode' in .hg/requires, that is,
a new repository filename layout (inside .hg/store).

Newly created repositories require 'dotencode' by default. Specifying

  [format]
  dotencode = False

in a config file will use the old format instead.

Prior Mercurial versions will abort with the message

   abort: requirement 'dotencode' not supported!

when trying to access a local repository that requires 'dotencode'.

New 'dotencode' repositories can be converted to the previous
repository format with

  hg --config format.dotencode=0 clone --pull repoA repoB

  $ cat > unix2mac.py <<EOF
  > import sys
  > 
  > for path in sys.argv[1:]:
  >     data = file(path, 'rb').read()
  >     data = data.replace('\n', '\r')
  >     file(path, 'wb').write(data)
  > EOF
  $ cat > print.py <<EOF
  > import sys
  > print(sys.stdin.read().replace('\n', '<LF>').replace('\r', '<CR>').replace('\0', '<NUL>'))
  > EOF
  $ hg init
  $ echo '[hooks]' >> .hg/hgrc
  $ echo 'pretxncommit.cr = python:hgext.win32text.forbidcr' >> .hg/hgrc
  $ echo 'pretxnchangegroup.cr = python:hgext.win32text.forbidcr' >> .hg/hgrc
  $ cat .hg/hgrc
  [hooks]
  pretxncommit.cr = python:hgext.win32text.forbidcr
  pretxnchangegroup.cr = python:hgext.win32text.forbidcr
  $ echo
  
  $ echo hello > f
  $ hg add f
  $ hg ci -m 1
  $ echo
  
  $ python unix2mac.py f
  $ hg ci -m 2
  Attempt to commit or push text file(s) using CR line endings
  in dea860dc51ec: f
  transaction abort!
  rollback completed
  abort: pretxncommit.cr hook failed
  [255]
  $ hg cat f | python print.py
  hello<LF>
  $ cat f | python print.py
  hello<CR>