vc-tests.el: vc-checkout-model

[Michael Albinus]

Hi,

in vc-tests.el test cases vc-test-<backend>04-checkout-model,
vc-checkout-model is tested. This function returns different results
for different backends. See the comments in vc-test--checkout-model:

;; Create empty repository.  Check repository checkout model.
;; nil: RCS
;; implicit: Bzr CVS Git Hg Mtn SRC SVN
;; locking: SCCS

;; Check checkout model of an empty file.
;; nil: RCS
;; implicit: Bzr CVS Git Hg Mtn SRC SVN
;; locking: SCCS

;; Write a new file.  Check checkout model.
;; nil: RCS
;; implicit: Bzr CVS Git Hg Mtn SRC SVN
;; locking: SCCS

;; Register a file.  Check checkout model.
;; nil: RCS
;; implicit: Bzr CVS Git Hg Mtn SRC SVN
;; locking: SCCS

;; Unregister the file.  Check checkout model.
;; nil: RCS
;; implicit: Bzr Git Hg
;; unsupported: CVS Mtn SCCS SRC SVN

Surprisingly, none of the calls returns `announced'. And the return
value in the RCS case (nil) is obviously wrong. I have no idea what the
correct state shall be, it looks to me strange. And the unsupported
state in the last test does not seem to be right.

Furthermore, there is no documentation about in doc/emacs/maintaining.texi.

Best regards, Michael.