view tests/test-mv-cp-st-diff.t @ 44651:00e0c5c06ed5

pycompat: change argv conversion semantics

Use of os.fsencode() to convert Python's sys.argv back to bytes
was not correct because it isn't the logically inverse operation
from what CPython was doing under the hood.

This commit changes the logic for doing the str -> bytes
conversion. This required a separate implementation for
POSIX and Windows.

The Windows behavior is arguably not ideal. The previous
behavior on Windows was leading to failing tests, such as
test-http-branchmap.t, which defines a utf-8 branch name
via a command argument. Previously, Mercurial's argument
parser looked to be receiving wchar_t bytes in some cases.
After this commit, behavior on Windows is compatible with
Python 2, where CPython did not implement `int wmain()` and
Windows was performing a Unicode to ANSI conversion on the
wchar_t native command line.

Arguably better behavior on Windows would be for Mercurial to
preserve the original Unicode sequence coming from Python and
to wrap this in a bytes-like type so we can round trip safely.
But, this would be new, backwards incompatible behavior. My
goal for this commit was to converge Mercurial behavior on
Python 3 on Windows to fix busted tests. And I believe I was
successful, as this commit fixes 9 tests on my Windows
machine and 14 tests in the AWS CI environment!

Differential Revision: https://phab.mercurial-scm.org/D8337

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

  $ hg mv f renamed
  $ hg ci -m renamed

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 and the rename. As f was untouched, we reuse the same
entry and the linkrev point to the older branch.

  $ hg graft -q 'desc(change)'
  $ hg graft -q 'desc(renamed)'

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

The copy tracking should still reach rev 3 (branch creation).
accessing the parent of 5 (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

Check debug output for copy tracing

  $ hg status --copies --rev 'desc(dev)' --rev . --config devel.debug.copies=yes --debug
  debug.copies: searching copies from a51f36ab1704 to 1f4aa1fd627b
  debug.copies: search mode: forward
  debug.copies:    looking into rename from a51f36ab1704 to 1f4aa1fd627b
  debug.copies:      missing files to search: 1
  debug.copies:        tracing file: renamed
  debug.copies:          rename of: f
  debug.copies:          time: * seconds (glob)
  A renamed
    f
  R f

Check that merging across the rename works

  $ echo modified >> renamed
  $ hg co -m 4
  merging renamed and f to f
  0 files updated, 1 files merged, 0 files removed, 0 files unresolved

  $ cd ..