tests/test-nested-repo.t

error: make HintException a mix-in class not derived from BaseException (API)

HintException is unrelated to the hierarchy of errors. It is an implementation
detail whether a class inherits from HintException or not, a sort of "private
inheritance" in C++.

New Hint isn't an exception class, which prevents catching error by its type:

    try:
        dosomething()
    except error.Hint:
        pass

Unfortunately, this passes on PyPy 5.3.1, but not on Python 2, and raises more
detailed TypeError on Python 3.

  $ hg init a
  $ cd a
  $ hg init b
  $ echo x > b/x

Should print nothing:

  $ hg add b
  $ hg st

  $ echo y > b/y
  $ hg st

Should fail:

  $ hg st b/x
  abort: path 'b/x' is inside nested repo 'b' (glob)
  [255]
  $ hg add b/x
  abort: path 'b/x' is inside nested repo 'b' (glob)
  [255]

Should fail:

  $ hg add b b/x
  abort: path 'b/x' is inside nested repo 'b' (glob)
  [255]
  $ hg st

Should arguably print nothing:

  $ hg st b

  $ echo a > a
  $ hg ci -Ama a

Should fail:

  $ hg mv a b
  abort: path 'b/a' is inside nested repo 'b' (glob)
  [255]
  $ hg st

  $ cd ..