view tests/test-mactext.t @ 25881:9de443515f1d stable

help: scripting help topic

There are a lot of non-human consumers of Mercurial. And the challenges
and considerations for machines consuming Mercurial is significantly
different from what humans face.

I think there are enough special considerations around how machines
consume Mercurial that a dedicated help topic is warranted. I concede
the audience for this topic is probably small compared to the general
audience. However, lots of normal Mercurial users do things like create
one-off shell scripts for common workflows that I think this is useful
enough to be in the install (as opposed to, say, a wiki page - which
most users will likely never find).

This text is by no means perfect. But you have to start somewhere. I
think I did cover the important parts, though.

  $ 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>