view tests/test-mv-cp-st-diff.t @ 33289:abd7dedbaa36

sparse: vendor Facebook-developed extension

Facebook has developed an extension to enable "sparse" checkouts -
a working directory with a subset of files. This feature is a critical
component in enabling repositories to scale to infinite number of
files while retaining reasonable performance. It's worth noting
that sparse checkout is only one possible solution to this problem:
another is virtual filesystems that realize files on first access.
But given that virtual filesystems may not be accessible to all
users, sparse checkout is necessary as a fallback.

Per mailing list discussion at
https://www.mercurial-scm.org/pipermail/mercurial-devel/2017-March/095868.html
we want to add sparse checkout to the Mercurial distribution via
roughly the following mechanism:

1. Vendor extension as-is with minimal modifications (this patch)
2. Refactor extension so it is more clearly experimental and inline
   with Mercurial practices
3. Move code from extension into core where possible
4. Drop experimental labeling and/or move feature into core
   after sign-off from narrow clone feature owners

This commit essentially copies the sparse extension and tests
from revision 71e0a2aeca92a4078fe1b8c76e32c88ff1929737 of the
https://bitbucket.org/facebook/hg-experimental repository.

A list of modifications made as part of vendoring is as follows:

* "EXPERIMENTAL" added to module docstring
* Imports were changed to match Mercurial style conventions
* "testedwith" value was updated to core Mercurial special value and
  comment boilerplate was inserted
* A "clone_sparse" function was renamed to "clonesparse" to appease
  the style checker
* Paths to the sparse extension in tests reflect built-in location
* test-sparse-extensions.t was renamed to test-sparse-fsmonitor.t
  and references to "simplecache" were removed. The test always skips
  because it isn't trivial to run it given the way we currently run
  fsmonitor tests
* A double empty line was removed from test-sparse-profiles.t

There are aspects of the added code that are obviously not ideal.
The goal is to make a minimal number of modifications as part of
the vendoring to make it easier to track changes from the original
implementation. Refactoring will occur in subsequent patches.

  $ add()
  > {
  >     echo $2 >> $1
  > }
  $ hg init t
  $ cd t

set up a boring main branch

  $ add a a
  $ hg add a
  $ mkdir x
  $ add x/x x
  $ hg add x/x
  $ hg ci -m0
  $ add a m1
  $ hg ci -m1
  $ add a m2
  $ add x/y y1
  $ hg add x/y
  $ hg ci -m2
  $ cd ..

  $ show()
  > {
  >     echo "# $2:"
  >     echo
  >     echo "% hg st -C $1"
  >     hg st -C $1
  >     echo
  >     echo "% hg diff --git $1"
  >     hg diff --git $1
  >     echo
  > }
  $ count=0

make a new branch and get diff/status output
$1 - first commit
$2 - second commit
$3 - working dir action

  $ tb()
  > {
  >     hg clone -q t t2 ; cd t2
  >     hg co -q -C 0
  > 
  >     echo % add a $count
  >     add a $count
  >     count=`expr $count + 1`
  >     echo % hg ci -m "t0"
  >     hg ci -m "t0"
  >     echo % $1
  >     $1
  >     echo % hg ci -m "t1"
  >     hg ci -m "t1"
  >     echo % $2
  >     $2
  >     echo % hg ci -m "t2"
  >     hg ci -m "t2"
  >     echo % $3
  >     $3
  >     echo
  >     show "" "working to parent"
  >     show "--rev 0" "working to root"
  >     show "--rev 2" "working to branch"
  >     show "--rev 0 --rev ." "root to parent"
  >     show "--rev . --rev 0" "parent to root"
  >     show "--rev 2 --rev ." "branch to parent"
  >     show "--rev . --rev 2" "parent to branch"
  >     echo
  >     cd ..
  >     rm -rf t2
  > }

rename in working dir

  $ tb "add a a1" "add a a2" "hg mv a b"
  % add a 0
  % hg ci -m t0
  created new head
  % add a a1
  % hg ci -m t1
  % add a a2
  % hg ci -m t2
  % hg mv a b
  
  # working to parent:
  
  % hg st -C 
  A b
    a
  R a
  
  % hg diff --git 
  diff --git a/a b/b
  rename from a
  rename to b
  
  # working to root:
  
  % hg st -C --rev 0
  A b
    a
  R a
  
  % hg diff --git --rev 0
  diff --git a/a b/b
  rename from a
  rename to b
  --- a/a
  +++ b/b
  @@ -1,1 +1,4 @@
   a
  +0
  +a1
  +a2
  
  # working to branch:
  
  % hg st -C --rev 2
  A b
    a
  R a
  R x/y
  
  % hg diff --git --rev 2
  diff --git a/a b/b
  rename from a
  rename to b
  --- a/a
  +++ b/b
  @@ -1,3 +1,4 @@
   a
  -m1
  -m2
  +0
  +a1
  +a2
  diff --git a/x/y b/x/y
  deleted file mode 100644
  --- a/x/y
  +++ /dev/null
  @@ -1,1 +0,0 @@
  -y1
  
  # root to parent:
  
  % hg st -C --rev 0 --rev .
  M a
  
  % hg diff --git --rev 0 --rev .
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,1 +1,4 @@
   a
  +0
  +a1
  +a2
  
  # parent to root:
  
  % hg st -C --rev . --rev 0
  M a
  
  % hg diff --git --rev . --rev 0
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,4 +1,1 @@
   a
  -0
  -a1
  -a2
  
  # branch to parent:
  
  % hg st -C --rev 2 --rev .
  M a
  R x/y
  
  % hg diff --git --rev 2 --rev .
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,3 +1,4 @@
   a
  -m1
  -m2
  +0
  +a1
  +a2
  diff --git a/x/y b/x/y
  deleted file mode 100644
  --- a/x/y
  +++ /dev/null
  @@ -1,1 +0,0 @@
  -y1
  
  # parent to branch:
  
  % hg st -C --rev . --rev 2
  M a
  A x/y
  
  % hg diff --git --rev . --rev 2
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,4 +1,3 @@
   a
  -0
  -a1
  -a2
  +m1
  +m2
  diff --git a/x/y b/x/y
  new file mode 100644
  --- /dev/null
  +++ b/x/y
  @@ -0,0 +1,1 @@
  +y1
  
  
copy in working dir

  $ tb "add a a1" "add a a2" "hg cp a b"
  % add a 1
  % hg ci -m t0
  created new head
  % add a a1
  % hg ci -m t1
  % add a a2
  % hg ci -m t2
  % hg cp a b
  
  # working to parent:
  
  % hg st -C 
  A b
    a
  
  % hg diff --git 
  diff --git a/a b/b
  copy from a
  copy to b
  
  # working to root:
  
  % hg st -C --rev 0
  M a
  A b
    a
  
  % hg diff --git --rev 0
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,1 +1,4 @@
   a
  +1
  +a1
  +a2
  diff --git a/a b/b
  copy from a
  copy to b
  --- a/a
  +++ b/b
  @@ -1,1 +1,4 @@
   a
  +1
  +a1
  +a2
  
  # working to branch:
  
  % hg st -C --rev 2
  M a
  A b
    a
  R x/y
  
  % hg diff --git --rev 2
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,3 +1,4 @@
   a
  -m1
  -m2
  +1
  +a1
  +a2
  diff --git a/a b/b
  copy from a
  copy to b
  --- a/a
  +++ b/b
  @@ -1,3 +1,4 @@
   a
  -m1
  -m2
  +1
  +a1
  +a2
  diff --git a/x/y b/x/y
  deleted file mode 100644
  --- a/x/y
  +++ /dev/null
  @@ -1,1 +0,0 @@
  -y1
  
  # root to parent:
  
  % hg st -C --rev 0 --rev .
  M a
  
  % hg diff --git --rev 0 --rev .
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,1 +1,4 @@
   a
  +1
  +a1
  +a2
  
  # parent to root:
  
  % hg st -C --rev . --rev 0
  M a
  
  % hg diff --git --rev . --rev 0
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,4 +1,1 @@
   a
  -1
  -a1
  -a2
  
  # branch to parent:
  
  % hg st -C --rev 2 --rev .
  M a
  R x/y
  
  % hg diff --git --rev 2 --rev .
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,3 +1,4 @@
   a
  -m1
  -m2
  +1
  +a1
  +a2
  diff --git a/x/y b/x/y
  deleted file mode 100644
  --- a/x/y
  +++ /dev/null
  @@ -1,1 +0,0 @@
  -y1
  
  # parent to branch:
  
  % hg st -C --rev . --rev 2
  M a
  A x/y
  
  % hg diff --git --rev . --rev 2
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,4 +1,3 @@
   a
  -1
  -a1
  -a2
  +m1
  +m2
  diff --git a/x/y b/x/y
  new file mode 100644
  --- /dev/null
  +++ b/x/y
  @@ -0,0 +1,1 @@
  +y1
  
  
single rename

  $ tb "hg mv a b" "add b b1" "add b w"
  % add a 2
  % hg ci -m t0
  created new head
  % hg mv a b
  % hg ci -m t1
  % add b b1
  % hg ci -m t2
  % add b w
  
  # working to parent:
  
  % hg st -C 
  M b
  
  % hg diff --git 
  diff --git a/b b/b
  --- a/b
  +++ b/b
  @@ -1,3 +1,4 @@
   a
   2
   b1
  +w
  
  # working to root:
  
  % hg st -C --rev 0
  A b
    a
  R a
  
  % hg diff --git --rev 0
  diff --git a/a b/b
  rename from a
  rename to b
  --- a/a
  +++ b/b
  @@ -1,1 +1,4 @@
   a
  +2
  +b1
  +w
  
  # working to branch:
  
  % hg st -C --rev 2
  A b
    a
  R a
  R x/y
  
  % hg diff --git --rev 2
  diff --git a/a b/b
  rename from a
  rename to b
  --- a/a
  +++ b/b
  @@ -1,3 +1,4 @@
   a
  -m1
  -m2
  +2
  +b1
  +w
  diff --git a/x/y b/x/y
  deleted file mode 100644
  --- a/x/y
  +++ /dev/null
  @@ -1,1 +0,0 @@
  -y1
  
  # root to parent:
  
  % hg st -C --rev 0 --rev .
  A b
    a
  R a
  
  % hg diff --git --rev 0 --rev .
  diff --git a/a b/b
  rename from a
  rename to b
  --- a/a
  +++ b/b
  @@ -1,1 +1,3 @@
   a
  +2
  +b1
  
  # parent to root:
  
  % hg st -C --rev . --rev 0
  A a
    b
  R b
  
  % hg diff --git --rev . --rev 0
  diff --git a/b b/a
  rename from b
  rename to a
  --- a/b
  +++ b/a
  @@ -1,3 +1,1 @@
   a
  -2
  -b1
  
  # branch to parent:
  
  % hg st -C --rev 2 --rev .
  A b
    a
  R a
  R x/y
  
  % hg diff --git --rev 2 --rev .
  diff --git a/a b/b
  rename from a
  rename to b
  --- a/a
  +++ b/b
  @@ -1,3 +1,3 @@
   a
  -m1
  -m2
  +2
  +b1
  diff --git a/x/y b/x/y
  deleted file mode 100644
  --- a/x/y
  +++ /dev/null
  @@ -1,1 +0,0 @@
  -y1
  
  # parent to branch:
  
  % hg st -C --rev . --rev 2
  A a
    b
  A x/y
  R b
  
  % hg diff --git --rev . --rev 2
  diff --git a/b b/a
  rename from b
  rename to a
  --- a/b
  +++ b/a
  @@ -1,3 +1,3 @@
   a
  -2
  -b1
  +m1
  +m2
  diff --git a/x/y b/x/y
  new file mode 100644
  --- /dev/null
  +++ b/x/y
  @@ -0,0 +1,1 @@
  +y1
  
  
single copy

  $ tb "hg cp a b" "add b b1" "add a w"
  % add a 3
  % hg ci -m t0
  created new head
  % hg cp a b
  % hg ci -m t1
  % add b b1
  % hg ci -m t2
  % add a w
  
  # working to parent:
  
  % hg st -C 
  M a
  
  % hg diff --git 
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,2 +1,3 @@
   a
   3
  +w
  
  # working to root:
  
  % hg st -C --rev 0
  M a
  A b
    a
  
  % hg diff --git --rev 0
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,1 +1,3 @@
   a
  +3
  +w
  diff --git a/a b/b
  copy from a
  copy to b
  --- a/a
  +++ b/b
  @@ -1,1 +1,3 @@
   a
  +3
  +b1
  
  # working to branch:
  
  % hg st -C --rev 2
  M a
  A b
    a
  R x/y
  
  % hg diff --git --rev 2
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,3 +1,3 @@
   a
  -m1
  -m2
  +3
  +w
  diff --git a/a b/b
  copy from a
  copy to b
  --- a/a
  +++ b/b
  @@ -1,3 +1,3 @@
   a
  -m1
  -m2
  +3
  +b1
  diff --git a/x/y b/x/y
  deleted file mode 100644
  --- a/x/y
  +++ /dev/null
  @@ -1,1 +0,0 @@
  -y1
  
  # root to parent:
  
  % hg st -C --rev 0 --rev .
  M a
  A b
    a
  
  % hg diff --git --rev 0 --rev .
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,1 +1,2 @@
   a
  +3
  diff --git a/a b/b
  copy from a
  copy to b
  --- a/a
  +++ b/b
  @@ -1,1 +1,3 @@
   a
  +3
  +b1
  
  # parent to root:
  
  % hg st -C --rev . --rev 0
  M a
  R b
  
  % hg diff --git --rev . --rev 0
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,2 +1,1 @@
   a
  -3
  diff --git a/b b/b
  deleted file mode 100644
  --- a/b
  +++ /dev/null
  @@ -1,3 +0,0 @@
  -a
  -3
  -b1
  
  # branch to parent:
  
  % hg st -C --rev 2 --rev .
  M a
  A b
    a
  R x/y
  
  % hg diff --git --rev 2 --rev .
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,3 +1,2 @@
   a
  -m1
  -m2
  +3
  diff --git a/a b/b
  copy from a
  copy to b
  --- a/a
  +++ b/b
  @@ -1,3 +1,3 @@
   a
  -m1
  -m2
  +3
  +b1
  diff --git a/x/y b/x/y
  deleted file mode 100644
  --- a/x/y
  +++ /dev/null
  @@ -1,1 +0,0 @@
  -y1
  
  # parent to branch:
  
  % hg st -C --rev . --rev 2
  M a
  A x/y
  R b
  
  % hg diff --git --rev . --rev 2
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,2 +1,3 @@
   a
  -3
  +m1
  +m2
  diff --git a/b b/b
  deleted file mode 100644
  --- a/b
  +++ /dev/null
  @@ -1,3 +0,0 @@
  -a
  -3
  -b1
  diff --git a/x/y b/x/y
  new file mode 100644
  --- /dev/null
  +++ b/x/y
  @@ -0,0 +1,1 @@
  +y1
  
  
rename chain

  $ tb "hg mv a b" "hg mv b c" "hg mv c d"
  % add a 4
  % hg ci -m t0
  created new head
  % hg mv a b
  % hg ci -m t1
  % hg mv b c
  % hg ci -m t2
  % hg mv c d
  
  # working to parent:
  
  % hg st -C 
  A d
    c
  R c
  
  % hg diff --git 
  diff --git a/c b/d
  rename from c
  rename to d
  
  # working to root:
  
  % hg st -C --rev 0
  A d
    a
  R a
  
  % hg diff --git --rev 0
  diff --git a/a b/d
  rename from a
  rename to d
  --- a/a
  +++ b/d
  @@ -1,1 +1,2 @@
   a
  +4
  
  # working to branch:
  
  % hg st -C --rev 2
  A d
    a
  R a
  R x/y
  
  % hg diff --git --rev 2
  diff --git a/a b/d
  rename from a
  rename to d
  --- a/a
  +++ b/d
  @@ -1,3 +1,2 @@
   a
  -m1
  -m2
  +4
  diff --git a/x/y b/x/y
  deleted file mode 100644
  --- a/x/y
  +++ /dev/null
  @@ -1,1 +0,0 @@
  -y1
  
  # root to parent:
  
  % hg st -C --rev 0 --rev .
  A c
    a
  R a
  
  % hg diff --git --rev 0 --rev .
  diff --git a/a b/c
  rename from a
  rename to c
  --- a/a
  +++ b/c
  @@ -1,1 +1,2 @@
   a
  +4
  
  # parent to root:
  
  % hg st -C --rev . --rev 0
  A a
    c
  R c
  
  % hg diff --git --rev . --rev 0
  diff --git a/c b/a
  rename from c
  rename to a
  --- a/c
  +++ b/a
  @@ -1,2 +1,1 @@
   a
  -4
  
  # branch to parent:
  
  % hg st -C --rev 2 --rev .
  A c
    a
  R a
  R x/y
  
  % hg diff --git --rev 2 --rev .
  diff --git a/a b/c
  rename from a
  rename to c
  --- a/a
  +++ b/c
  @@ -1,3 +1,2 @@
   a
  -m1
  -m2
  +4
  diff --git a/x/y b/x/y
  deleted file mode 100644
  --- a/x/y
  +++ /dev/null
  @@ -1,1 +0,0 @@
  -y1
  
  # parent to branch:
  
  % hg st -C --rev . --rev 2
  A a
    c
  A x/y
  R c
  
  % hg diff --git --rev . --rev 2
  diff --git a/c b/a
  rename from c
  rename to a
  --- a/c
  +++ b/a
  @@ -1,2 +1,3 @@
   a
  -4
  +m1
  +m2
  diff --git a/x/y b/x/y
  new file mode 100644
  --- /dev/null
  +++ b/x/y
  @@ -0,0 +1,1 @@
  +y1
  
  
copy chain

  $ tb "hg cp a b" "hg cp b c" "hg cp c d"
  % add a 5
  % hg ci -m t0
  created new head
  % hg cp a b
  % hg ci -m t1
  % hg cp b c
  % hg ci -m t2
  % hg cp c d
  
  # working to parent:
  
  % hg st -C 
  A d
    c
  
  % hg diff --git 
  diff --git a/c b/d
  copy from c
  copy to d
  
  # working to root:
  
  % hg st -C --rev 0
  M a
  A b
    a
  A c
    a
  A d
    a
  
  % hg diff --git --rev 0
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,1 +1,2 @@
   a
  +5
  diff --git a/a b/b
  copy from a
  copy to b
  --- a/a
  +++ b/b
  @@ -1,1 +1,2 @@
   a
  +5
  diff --git a/a b/c
  copy from a
  copy to c
  --- a/a
  +++ b/c
  @@ -1,1 +1,2 @@
   a
  +5
  diff --git a/a b/d
  copy from a
  copy to d
  --- a/a
  +++ b/d
  @@ -1,1 +1,2 @@
   a
  +5
  
  # working to branch:
  
  % hg st -C --rev 2
  M a
  A b
    a
  A c
    a
  A d
    a
  R x/y
  
  % hg diff --git --rev 2
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,3 +1,2 @@
   a
  -m1
  -m2
  +5
  diff --git a/a b/b
  copy from a
  copy to b
  --- a/a
  +++ b/b
  @@ -1,3 +1,2 @@
   a
  -m1
  -m2
  +5
  diff --git a/a b/c
  copy from a
  copy to c
  --- a/a
  +++ b/c
  @@ -1,3 +1,2 @@
   a
  -m1
  -m2
  +5
  diff --git a/a b/d
  copy from a
  copy to d
  --- a/a
  +++ b/d
  @@ -1,3 +1,2 @@
   a
  -m1
  -m2
  +5
  diff --git a/x/y b/x/y
  deleted file mode 100644
  --- a/x/y
  +++ /dev/null
  @@ -1,1 +0,0 @@
  -y1
  
  # root to parent:
  
  % hg st -C --rev 0 --rev .
  M a
  A b
    a
  A c
    a
  
  % hg diff --git --rev 0 --rev .
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,1 +1,2 @@
   a
  +5
  diff --git a/a b/b
  copy from a
  copy to b
  --- a/a
  +++ b/b
  @@ -1,1 +1,2 @@
   a
  +5
  diff --git a/a b/c
  copy from a
  copy to c
  --- a/a
  +++ b/c
  @@ -1,1 +1,2 @@
   a
  +5
  
  # parent to root:
  
  % hg st -C --rev . --rev 0
  M a
  R b
  R c
  
  % hg diff --git --rev . --rev 0
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,2 +1,1 @@
   a
  -5
  diff --git a/b b/b
  deleted file mode 100644
  --- a/b
  +++ /dev/null
  @@ -1,2 +0,0 @@
  -a
  -5
  diff --git a/c b/c
  deleted file mode 100644
  --- a/c
  +++ /dev/null
  @@ -1,2 +0,0 @@
  -a
  -5
  
  # branch to parent:
  
  % hg st -C --rev 2 --rev .
  M a
  A b
    a
  A c
    a
  R x/y
  
  % hg diff --git --rev 2 --rev .
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,3 +1,2 @@
   a
  -m1
  -m2
  +5
  diff --git a/a b/b
  copy from a
  copy to b
  --- a/a
  +++ b/b
  @@ -1,3 +1,2 @@
   a
  -m1
  -m2
  +5
  diff --git a/a b/c
  copy from a
  copy to c
  --- a/a
  +++ b/c
  @@ -1,3 +1,2 @@
   a
  -m1
  -m2
  +5
  diff --git a/x/y b/x/y
  deleted file mode 100644
  --- a/x/y
  +++ /dev/null
  @@ -1,1 +0,0 @@
  -y1
  
  # parent to branch:
  
  % hg st -C --rev . --rev 2
  M a
  A x/y
  R b
  R c
  
  % hg diff --git --rev . --rev 2
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,2 +1,3 @@
   a
  -5
  +m1
  +m2
  diff --git a/b b/b
  deleted file mode 100644
  --- a/b
  +++ /dev/null
  @@ -1,2 +0,0 @@
  -a
  -5
  diff --git a/c b/c
  deleted file mode 100644
  --- a/c
  +++ /dev/null
  @@ -1,2 +0,0 @@
  -a
  -5
  diff --git a/x/y b/x/y
  new file mode 100644
  --- /dev/null
  +++ b/x/y
  @@ -0,0 +1,1 @@
  +y1
  
  
circular rename

  $ tb "add a a1" "hg mv a b" "hg mv b a"
  % add a 6
  % hg ci -m t0
  created new head
  % add a a1
  % hg ci -m t1
  % hg mv a b
  % hg ci -m t2
  % hg mv b a
  
  # working to parent:
  
  % hg st -C 
  A a
    b
  R b
  
  % hg diff --git 
  diff --git a/b b/a
  rename from b
  rename to a
  
  # working to root:
  
  % hg st -C --rev 0
  M a
  
  % hg diff --git --rev 0
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,1 +1,3 @@
   a
  +6
  +a1
  
  # working to branch:
  
  % hg st -C --rev 2
  M a
  R x/y
  
  % hg diff --git --rev 2
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,3 +1,3 @@
   a
  -m1
  -m2
  +6
  +a1
  diff --git a/x/y b/x/y
  deleted file mode 100644
  --- a/x/y
  +++ /dev/null
  @@ -1,1 +0,0 @@
  -y1
  
  # root to parent:
  
  % hg st -C --rev 0 --rev .
  A b
    a
  R a
  
  % hg diff --git --rev 0 --rev .
  diff --git a/a b/b
  rename from a
  rename to b
  --- a/a
  +++ b/b
  @@ -1,1 +1,3 @@
   a
  +6
  +a1
  
  # parent to root:
  
  % hg st -C --rev . --rev 0
  A a
    b
  R b
  
  % hg diff --git --rev . --rev 0
  diff --git a/b b/a
  rename from b
  rename to a
  --- a/b
  +++ b/a
  @@ -1,3 +1,1 @@
   a
  -6
  -a1
  
  # branch to parent:
  
  % hg st -C --rev 2 --rev .
  A b
    a
  R a
  R x/y
  
  % hg diff --git --rev 2 --rev .
  diff --git a/a b/b
  rename from a
  rename to b
  --- a/a
  +++ b/b
  @@ -1,3 +1,3 @@
   a
  -m1
  -m2
  +6
  +a1
  diff --git a/x/y b/x/y
  deleted file mode 100644
  --- a/x/y
  +++ /dev/null
  @@ -1,1 +0,0 @@
  -y1
  
  # parent to branch:
  
  % hg st -C --rev . --rev 2
  A a
    b
  A x/y
  R b
  
  % hg diff --git --rev . --rev 2
  diff --git a/b b/a
  rename from b
  rename to a
  --- a/b
  +++ b/a
  @@ -1,3 +1,3 @@
   a
  -6
  -a1
  +m1
  +m2
  diff --git a/x/y b/x/y
  new file mode 100644
  --- /dev/null
  +++ b/x/y
  @@ -0,0 +1,1 @@
  +y1
  
  
directory move

  $ tb "hg mv x y" "add y/x x1" "add y/x x2"
  % add a 7
  % hg ci -m t0
  created new head
  % hg mv x y
  moving x/x to y/x (glob)
  % hg ci -m t1
  % add y/x x1
  % hg ci -m t2
  % add y/x x2
  
  # working to parent:
  
  % hg st -C 
  M y/x
  
  % hg diff --git 
  diff --git a/y/x b/y/x
  --- a/y/x
  +++ b/y/x
  @@ -1,2 +1,3 @@
   x
   x1
  +x2
  
  # working to root:
  
  % hg st -C --rev 0
  M a
  A y/x
    x/x
  R x/x
  
  % hg diff --git --rev 0
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,1 +1,2 @@
   a
  +7
  diff --git a/x/x b/y/x
  rename from x/x
  rename to y/x
  --- a/x/x
  +++ b/y/x
  @@ -1,1 +1,3 @@
   x
  +x1
  +x2
  
  # working to branch:
  
  % hg st -C --rev 2
  M a
  A y/x
    x/x
  R x/x
  R x/y
  
  % hg diff --git --rev 2
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,3 +1,2 @@
   a
  -m1
  -m2
  +7
  diff --git a/x/y b/x/y
  deleted file mode 100644
  --- a/x/y
  +++ /dev/null
  @@ -1,1 +0,0 @@
  -y1
  diff --git a/x/x b/y/x
  rename from x/x
  rename to y/x
  --- a/x/x
  +++ b/y/x
  @@ -1,1 +1,3 @@
   x
  +x1
  +x2
  
  # root to parent:
  
  % hg st -C --rev 0 --rev .
  M a
  A y/x
    x/x
  R x/x
  
  % hg diff --git --rev 0 --rev .
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,1 +1,2 @@
   a
  +7
  diff --git a/x/x b/y/x
  rename from x/x
  rename to y/x
  --- a/x/x
  +++ b/y/x
  @@ -1,1 +1,2 @@
   x
  +x1
  
  # parent to root:
  
  % hg st -C --rev . --rev 0
  M a
  A x/x
    y/x
  R y/x
  
  % hg diff --git --rev . --rev 0
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,2 +1,1 @@
   a
  -7
  diff --git a/y/x b/x/x
  rename from y/x
  rename to x/x
  --- a/y/x
  +++ b/x/x
  @@ -1,2 +1,1 @@
   x
  -x1
  
  # branch to parent:
  
  % hg st -C --rev 2 --rev .
  M a
  A y/x
    x/x
  R x/x
  R x/y
  
  % hg diff --git --rev 2 --rev .
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,3 +1,2 @@
   a
  -m1
  -m2
  +7
  diff --git a/x/y b/x/y
  deleted file mode 100644
  --- a/x/y
  +++ /dev/null
  @@ -1,1 +0,0 @@
  -y1
  diff --git a/x/x b/y/x
  rename from x/x
  rename to y/x
  --- a/x/x
  +++ b/y/x
  @@ -1,1 +1,2 @@
   x
  +x1
  
  # parent to branch:
  
  % hg st -C --rev . --rev 2
  M a
  A x/x
    y/x
  A x/y
  R y/x
  
  % hg diff --git --rev . --rev 2
  diff --git a/a b/a
  --- a/a
  +++ b/a
  @@ -1,2 +1,3 @@
   a
  -7
  +m1
  +m2
  diff --git a/y/x b/x/x
  rename from y/x
  rename to x/x
  --- a/y/x
  +++ b/x/x
  @@ -1,2 +1,1 @@
   x
  -x1
  diff --git a/x/y b/x/y
  new file mode 100644
  --- /dev/null
  +++ b/x/y
  @@ -0,0 +1,1 @@
  +y1
  
  

Cannot implement unrelated branch with tb
testing copies with unrelated branch

  $ hg init unrelated
  $ cd unrelated
  $ echo a >> a
  $ hg ci -Am adda
  adding a
  $ hg mv a b
  $ hg ci -m movea
  $ hg up -C null
  0 files updated, 0 files merged, 1 files removed, 0 files unresolved
  $ echo a >> a
  $ hg ci -Am addunrelateda
  adding a
  created new head

unrelated branch diff

  $ hg diff --git -r 2 -r 1
  diff --git a/a b/a
  deleted file mode 100644
  --- a/a
  +++ /dev/null
  @@ -1,1 +0,0 @@
  -a
  diff --git a/b b/b
  new file mode 100644
  --- /dev/null
  +++ b/b
  @@ -0,0 +1,1 @@
  +a
  $ cd ..


test for case where we didn't look sufficiently far back to find rename ancestor

  $ hg init diffstop
  $ cd diffstop
  $ echo > f
  $ hg ci -qAmf
  $ hg mv f g
  $ hg ci -m'f->g'
  $ hg up -qr0
  $ touch x
  $ hg ci -qAmx
  $ echo f > f
  $ hg ci -qmf=f
  $ hg merge -q
  $ hg ci -mmerge
  $ hg log -G --template '{rev}  {desc}'
  @    4  merge
  |\
  | o  3  f=f
  | |
  | o  2  x
  | |
  o |  1  f->g
  |/
  o  0  f
  
  $ hg diff --git -r 2
  diff --git a/f b/g
  rename from f
  rename to g
  --- a/f
  +++ b/g
  @@ -1,1 +1,1 @@
  -
  +f
  $ cd ..

Additional tricky linkrev case
------------------------------

If the first file revision after the diff base has a linkrev pointing to a
changeset on another branch with a revision lower that the diff base, we can
jump past the copy detection limit and fail to detect the rename.

  $ hg init diffstoplinkrev
  $ cd diffstoplinkrev

  $ touch f
  $ hg ci -Aqm 'empty f'

Make a simple change

  $ echo change > f
  $ hg ci -m 'change f'

Make a second branch, we use a named branch to create a simple commit
that does not touch f.

  $ hg up -qr 'desc(empty)'
  $ hg branch -q dev
  $ hg ci -Aqm dev

Graft the initial change, as f was untouched, we reuse the same entry and the
linkrev point to the older branch.

  $ hg graft -q 'desc(change)'

Make a rename because we want to track renames. It is also important that the
faulty linkrev is not the "start" commit to ensure the linkrev will be used.

  $ hg mv f renamed
  $ hg ci -m renamed

  $ hg log -G -T '{rev} {desc}'
  @  4 renamed
  |
  o  3 change f
  |
  o  2 dev
  |
  | o  1 change f
  |/
  o  0 empty f
  

The copy tracking should still reach rev 2 (branch creation).
accessing the parent of 4 (renamed) should not jump use to revision 1.

  $ hg diff --git -r 'desc(dev)' -r .
  diff --git a/f b/renamed
  rename from f
  rename to renamed
  --- a/f
  +++ b/renamed
  @@ -0,0 +1,1 @@
  +change

  $ cd ..