tests/test-mactext.t

util: adjust hgcmd() to handle frozen Mercurial on OS X

Previously, 'hg serve -d' was trying to exec the bundled python executable,
which failed with:

    Unknown option: --
    usage: python [option] ...
    Try 'python -h'...
    abort: child process failed to start

See the previous patch for details about the content of the various command
variables.  Note that unlike the previous patch here an application bundling
Mercurial could set $HG in the environment to get the correct result, there
isn't anything that a bundling application could do to get the correct result
here.

'hg serve -d' now launches under TortoiseHg, and there is a process listed in
the background, but a client process cannot connect to it for some reason, so
more investigation is needed.

  $ 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 hello > f
  $ hg add f
  $ hg ci -m 1

  $ 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>