view tests/test-debugrename.t @ 44838:c802ec4f7196

rust-status: collect traversed directories if required

Some commands (`hg purge` notably) register the `traversedir` callback on their
matcher to run said callback every time a directory is traversed.

This is the first of three patches, further broadening Rust support for status.

Unfortunately, there is no way around collecting a full `Vec` (or any other
owned datastructure, like a radix tree) and pushing it back up the Python layer
since keeping the Python callback in a closure would mean giving up
multithreading because of the GIL, which is obviously unacceptable.

Performance is still a lot better than the Python+C path.

Running `hg clean/purge` on Netbeans' repo (100k files):

```
     | No-op | 30% unknown
--------------------------
Rust | 1.0s  | 1.67s
C    | 2.0s  | 2.87s
```

Differential Revision: https://phab.mercurial-scm.org/D8518

  $ hg init
  $ echo a > a
  $ hg ci -Am t
  adding a

  $ hg mv a b
  $ hg ci -Am t1
  $ hg debugrename b
  b renamed from a:b789fdd96dc2f3bd229c1dd8eedf0fc60e2b68e3

  $ hg mv b a
  $ hg ci -Am t2
  $ hg debugrename a
  a renamed from b:37d9b5d994eab34eda9c16b195ace52c7b129980

  $ hg debugrename --rev 1 b
  b renamed from a:b789fdd96dc2f3bd229c1dd8eedf0fc60e2b68e3