tests/test-pull-http.t

ui: add special-purpose atexit functionality

In spite of its longstanding use, Python's built-in atexit code is
not suitable for Mercurial's purposes, for several reasons:

* Handlers run after application code has finished.

* Because of this, the code that runs handlers swallows exceptions
  (since there's no possible stacktrace to associate errors with).
  If we're lucky, we'll get something spat out to stderr (if stderr
  still works), which of course isn't any use in a big deployment
  where it's important that exceptions get logged and aggregated.

* Mercurial's current atexit handlers make unfortunate assumptions
  about process state (specifically stdio) that, coupled with the
  above problems, make it impossible to deal with certain categories
  of error (try "hg status > /dev/full" on a Linux box).

* In Python 3, the atexit implementation is completely hidden, so
  we can't hijack the platform's atexit code to run handlers at a
  time of our choosing.

As a result, here's a perfectly cromulent atexit-like implementation
over which we have control.  This lets us decide exactly when the
handlers run (after each request has completed), and control what
the process state is when that occurs (and afterwards).

#require killdaemons

  $ hg init test
  $ cd test
  $ echo a > a
  $ hg ci -Ama
  adding a
  $ cd ..
  $ hg clone test test2
  updating to branch default
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cd test2
  $ echo a >> a
  $ hg ci -mb

Cloning with a password in the URL should not save the password in .hg/hgrc:

  $ hg serve -p $HGPORT -d --pid-file=hg.pid -E errors.log
  $ cat hg.pid >> $DAEMON_PIDS
  $ hg clone http://foo:xyzzy@localhost:$HGPORT/ test3
  requesting all changes
  adding changesets
  adding manifests
  adding file changes
  added 2 changesets with 2 changes to 1 files
  updating to branch default
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ cat test3/.hg/hgrc
  # example repository config (see 'hg help config' for more info)
  [paths]
  default = http://foo@localhost:$HGPORT/
  
  # path aliases to other clones of this repo in URLs or filesystem paths
  # (see 'hg help config.paths' for more info)
  #
  # default:pushurl = ssh://[e-mail]/hg/jdoes-fork
  # my-fork         = ssh://[e-mail]/hg/jdoes-fork
  # my-clone        = /home/jdoe/jdoes-clone
  
  [ui]
  # name and email (local to this repository, optional), e.g.
  # username = Jane Doe <[e-mail]>
  $ killdaemons.py

expect error, cloning not allowed

  $ echo '[web]' > .hg/hgrc
  $ echo 'allowpull = false' >> .hg/hgrc
  $ hg serve -p $HGPORT -d --pid-file=hg.pid -E errors.log
  $ cat hg.pid >> $DAEMON_PIDS
  $ hg clone http://localhost:$HGPORT/ test4 # bundle2+
  requesting all changes
  abort: authorization failed
  [255]
  $ hg clone http://localhost:$HGPORT/ test4 --config devel.legacy.exchange=bundle1
  abort: authorization failed
  [255]
  $ killdaemons.py

serve errors

  $ cat errors.log
  $ req() {
  >     hg serve -p $HGPORT -d --pid-file=hg.pid -E errors.log
  >     cat hg.pid >> $DAEMON_PIDS
  >     hg --cwd ../test pull http://localhost:$HGPORT/
  >     killdaemons.py hg.pid
  >     echo % serve errors
  >     cat errors.log
  > }

expect error, pulling not allowed

  $ req
  pulling from http://localhost:$HGPORT/
  searching for changes
  abort: authorization failed
  % serve errors

  $ cd ..