tests/test-diff-change.t

largefiles: replace invocation of os.path module by vfs in lfutil.py

Replaces invocations os.path functions to methods in vfs. Unfortunately
(in my view) this makes code less readable, because instead of using
clear variable names with path it needs to replace them with vfs(..).
I need guidance how to make such transition look more readable.

For example in this patch there is example with few places with
wvfs.join(standindir), standindir before this patch was absolute
path, in this it is changed to relative because it is used also
in expression wvfs.join(standindir, pat).

Testing diff --change

  $ hg init a
  $ cd a

  $ echo "first" > file.txt
  $ hg add file.txt
  $ hg commit -m 'first commit' # 0

  $ echo "second" > file.txt
  $ hg commit -m 'second commit' # 1

  $ echo "third" > file.txt
  $ hg commit -m 'third commit' # 2

  $ hg diff --nodates --change 1
  diff -r 4bb65dda5db4 -r e9b286083166 file.txt
  --- a/file.txt
  +++ b/file.txt
  @@ -1,1 +1,1 @@
  -first
  +second

  $ hg diff --change e9b286083166
  diff -r 4bb65dda5db4 -r e9b286083166 file.txt
  --- a/file.txt	Thu Jan 01 00:00:00 1970 +0000
  +++ b/file.txt	Thu Jan 01 00:00:00 1970 +0000
  @@ -1,1 +1,1 @@
  -first
  +second

  $ cd ..

Test dumb revspecs: top-level "x:y", "x:", ":y" and ":" ranges should be handled
as pairs even if x == y, but not for "f(x:y)" nor "x::y" (issue3474, issue4774)

  $ hg clone -q a dumbspec
  $ cd dumbspec
  $ echo "wdir" > file.txt

  $ hg diff -r 2:2
  $ hg diff -r 2:.
  $ hg diff -r 2:
  $ hg diff -r :0
  $ hg diff -r '2:first(2:2)'
  $ hg diff -r 'first(2:2)' --nodates
  diff -r bf5ff72eb7e0 file.txt
  --- a/file.txt
  +++ b/file.txt
  @@ -1,1 +1,1 @@
  -third
  +wdir
  $ hg diff -r 2::2 --nodates
  diff -r bf5ff72eb7e0 file.txt
  --- a/file.txt
  +++ b/file.txt
  @@ -1,1 +1,1 @@
  -third
  +wdir
  $ hg diff -r "2 and 1"
  abort: empty revision range
  [255]

  $ cd ..

  $ hg clone -qr0 a dumbspec-rev0
  $ cd dumbspec-rev0
  $ echo "wdir" > file.txt

  $ hg diff -r :
  $ hg diff -r 'first(:)' --nodates
  diff -r 4bb65dda5db4 file.txt
  --- a/file.txt
  +++ b/file.txt
  @@ -1,1 +1,1 @@
  -first
  +wdir

  $ cd ..

Testing diff --change when merge:

  $ cd a

  $ for i in 1 2 3 4 5 6 7 8 9 10; do
  >    echo $i >> file.txt
  > done
  $ hg commit -m "lots of text" # 3

  $ sed -e 's,^2$,x,' file.txt > file.txt.tmp
  $ mv file.txt.tmp file.txt
  $ hg commit -m "change 2 to x" # 4

  $ hg up -r 3
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ sed -e 's,^8$,y,' file.txt > file.txt.tmp
  $ mv file.txt.tmp file.txt
  $ hg commit -m "change 8 to y"
  created new head

  $ hg up -C -r 4
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg merge -r 5
  merging file.txt
  0 files updated, 1 files merged, 0 files removed, 0 files unresolved
  (branch merge, don't forget to commit)
  $ hg commit -m "merge 8 to y" # 6

  $ hg diff --change 5
  diff -r ae119d680c82 -r 9085c5c02e52 file.txt
  --- a/file.txt	Thu Jan 01 00:00:00 1970 +0000
  +++ b/file.txt	Thu Jan 01 00:00:00 1970 +0000
  @@ -6,6 +6,6 @@
   5
   6
   7
  -8
  +y
   9
   10

must be similar to 'hg diff --change 5':

  $ hg diff -c 6
  diff -r 273b50f17c6d -r 979ca961fd2e file.txt
  --- a/file.txt	Thu Jan 01 00:00:00 1970 +0000
  +++ b/file.txt	Thu Jan 01 00:00:00 1970 +0000
  @@ -6,6 +6,6 @@
   5
   6
   7
  -8
  +y
   9
   10

  $ cd ..