bdiff: use Python memory allocator in fixws
Python has its own memory allocation APIs. For allocations
<= 512 bytes, it allocates memory from arenas. This means that
average small allocations don't call the system allocator, which
makes them faster. Also, arena allocations cut down on memory
fragmentation, which can matter for performance in long-running
processes.
Another advantage of using the Python memory allocator is that
allocations are tracked by Python. This is a bigger deal in
Python 3, as modern versions of Python have some decent built-in
tools for examining memory usage, leaks, etc.
This patch converts a trivial malloc() + free() in the bdiff code
to use the Python allocator APIs. Since the object being
operated on is a line, chances are it will use an arena. So,
this could have a net positive impact on performance (although
I didn't measure it).
Test update logic when there are renames or weird same-name cases between dirs
and files
Update with local changes across a file rename
$ hg init r1 && cd r1
$ echo a > a
$ hg add a
$ hg ci -m a
$ hg mv a b
$ hg ci -m rename
$ echo b > b
$ hg ci -m change
$ hg up -q 0
$ echo c > a
$ hg up
merging a and b to b
warning: conflicts while merging b! (edit, then use 'hg resolve --mark')
0 files updated, 0 files merged, 0 files removed, 1 files unresolved
use 'hg resolve' to retry unresolved file merges
[1]
Test update when local untracked directory exists with the same name as a
tracked file in a commit we are updating to
$ hg init r2 && cd r2
$ echo root > root && hg ci -Am root # rev 0
adding root
$ echo text > name && hg ci -Am "name is a file" # rev 1
adding name
$ hg up 0
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ mkdir name
$ hg up 1
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
Test update when local untracked directory exists with some files in it and has
the same name a tracked file in a commit we are updating to. In future this
should be updated to give an friendlier error message, but now we should just
make sure that this does not erase untracked data
$ hg up 0
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ mkdir name
$ echo text > name/file
$ hg st
? name/file
$ hg up 1
abort: *: '$TESTTMP/r1/r2/name' (glob)
[255]
$ cd ..
#if symlink
Test update when two commits have symlinks that point to different folders
$ hg init r3 && cd r3
$ echo root > root && hg ci -Am root
adding root
$ mkdir folder1 && mkdir folder2
$ ln -s folder1 folder
$ hg ci -Am "symlink to folder1"
adding folder
$ rm folder
$ ln -s folder2 folder
$ hg ci -Am "symlink to folder2"
$ hg up 1
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd ..
#endif
#if rmcwd
Test that warning is printed if cwd is deleted during update
$ hg init r4 && cd r4
$ mkdir dir
$ cd dir
$ echo a > a
$ echo b > b
$ hg add a b
$ hg ci -m "file and dir"
$ hg up -q null
current directory was removed
(consider changing to repo root: $TESTTMP/r1/r4)
#endif