tests/test-revset-outgoing.t

posix, windows: introduce cachestat

This class contains a stat result, and possibly other file info to reliably
determine between two points in time whether a file has changed.

Uniquely identifying a file gives us that reliability because we either
atomic rename or append. So one of two will happen: the file 'id' will change,
or the size of the file will change.

posix implements it simply by calling os.stat() and checking if the result
has st_ino.

For now on Windows we always assume the path is uncacheable. This can be
improved on NTFS due to file IDs: http://msdn.microsoft.com/en-us/library/aa363788(v=vs.85).aspx

So we need to find out if a file path is on an NTFS drive, for that we have:

- GetVolumeInformation, which unfortunately only works with a root path (but is available on XP)
- GetVolumeInformationByHandleW, works on a full file path but requires Vista or higher

  $ cat >> $HGRCPATH <<EOF
  > [extensions]
  > graphlog=
  > 
  > [alias]
  > tlog = log --template "{rev}:{node|short}: '{desc}' {branches}\n"
  > tglog = tlog -G
  > tout = out --template "{rev}:{node|short}: '{desc}' {branches}\n"
  > EOF

  $ hg init a
  $ cd a

  $ echo a > a
  $ hg ci -Aqm0

  $ echo foo >> a
  $ hg ci -Aqm1

  $ hg up -q 0

  $ hg branch stable
  marked working directory as branch stable
  $ echo bar >> a
  $ hg ci -qm2

  $ hg tglog
  @  2:7bee6c3bea3a: '2' stable
  |
  | o  1:3560197d8331: '1'
  |/
  o  0:f7b1eb17ad24: '0'
  

  $ cd ..

  $ hg clone -q a#stable b

  $ cd b
  $ cat .hg/hgrc
  [paths]
  default = $TESTTMP/a#stable

  $ echo red >> a
  $ hg ci -qm3

  $ hg up -q default

  $ echo blue >> a
  $ hg ci -qm4

  $ hg tglog
  @  3:f0461977a3db: '4'
  |
  | o  2:1d4099801a4e: '3' stable
  | |
  | o  1:7bee6c3bea3a: '2' stable
  |/
  o  0:f7b1eb17ad24: '0'
  

  $ hg tout
  comparing with $TESTTMP/a
  searching for changes
  2:1d4099801a4e: '3' stable

  $ hg tlog -r 'outgoing()'
  2:1d4099801a4e: '3' stable

  $ hg tout ../a#default
  comparing with ../a
  searching for changes
  3:f0461977a3db: '4' 

  $ hg tlog -r 'outgoing("../a#default")'
  3:f0461977a3db: '4' 

  $ echo "green = ../a#default" >> .hg/hgrc

  $ cat .hg/hgrc
  [paths]
  default = $TESTTMP/a#stable
  green = ../a#default

  $ hg tout green
  comparing with $TESTTMP/a
  searching for changes
  3:f0461977a3db: '4' 

  $ hg tlog -r 'outgoing("green")'
  3:f0461977a3db: '4'