subrepo: add test for Windows relative-ish path with drive letter
Matt Harbison pointed out that Windows had some weird path syntax.
Fortunately it's rejected appropriately by pathauditor, so we're safe.
Let's test the behavior as we have a special handling for Windows drive
letters.
This patch includes a basic example. Maybe we'll need to extend the test
case further, but writing such tests on Linux isn't easy.
$ rm -rf a
$ hg init a
$ cd a
$ echo a > a
$ hg ci -Am0
adding a
$ hg tag t1 # 1
$ hg tag --remove t1 # 2
$ hg co 1
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg tag -f -r0 t1
$ hg tags
tip 3:a49829c4fc11
t1 0:f7b1eb17ad24
$ cd ..