Further vcs-cvs/rcs-responsible-p updates from master

* lisp/vc/vc-bzr.el (vc-bzr-responsible-p):
* lisp/vc/vc-sccs.el (vc-sccs-responsible-p):
* lisp/vc/vc-dav.el (vc-dav-responsible-p): Update doc string.

* lisp/vc/vc-rcs.el (vc-rcs-responsible-p):
* lisp/vc/vc-cvs.el (vc-cvs-responsible-p): Further fixes from
master.

* lisp/vc/vc-src.el (vc-src-responsible-p): Return the directory.

* lisp/vc/vc.el: Update comments.

7 files changed, 16 insertions, 14 deletions

diff --git a/lisp/vc/vc-bzr.el b/lisp/vc/vc-bzr.el
index 836630acb5d..ee394a93af4 100644
--- a/lisp/vc/vc-bzr.el
+++ b/lisp/vc/vc-bzr.el
@@ -640,7 +640,7 @@ Returns nil if unable to find this information."
 ;; Could run `bzr status' in the directory and see if it succeeds, but
 ;; that's relatively expensive.
 (defalias 'vc-bzr-responsible-p #'vc-bzr-root
-  "Return non-nil if FILE is (potentially) controlled by bzr.
+  "Return the directory if FILE is (potentially) controlled by bzr.
 The criterion is that there is a `.bzr' directory in the same
 or a superior directory.")
 
diff --git a/lisp/vc/vc-cvs.el b/lisp/vc/vc-cvs.el
index e4524db951b..8f06d5a847a 100644
--- a/lisp/vc/vc-cvs.el
+++ b/lisp/vc/vc-cvs.el
@@ -308,12 +308,12 @@ to the CVS command."
          (vc-switches 'CVS 'register)))
 
 (defun vc-cvs-responsible-p (file)
-  "Return non-nil if CVS thinks it is responsible for FILE."
+  "Return the directory if CVS thinks it is responsible for FILE."
   (let ((dir (if (file-directory-p file)
 	         file
 	       (file-name-directory file))))
     (and (file-directory-p (expand-file-name "CVS" dir))
-         dir)))
+         (file-name-directory (expand-file-name "CVS" dir)))))
 
 (defun vc-cvs-could-register (file)
   "Return non-nil if FILE could be registered in CVS.
diff --git a/lisp/vc/vc-dav.el b/lisp/vc/vc-dav.el
index 61e2cd23900..94621599e4a 100644
--- a/lisp/vc/vc-dav.el
+++ b/lisp/vc/vc-dav.el
@@ -137,9 +137,9 @@ It should return a status of either 0 (no differences found), or
   )
 
 (defun vc-dav-responsible-p (url)
-  "Return non-nil if DAV considers itself `responsible' for URL."
+  "Return the URL if DAV considers itself `responsible' for URL."
   ;; Check for DAV support on the web server.
-  (and t url))
+  url)
 
 ;;; Unimplemented functions
 ;;
diff --git a/lisp/vc/vc-rcs.el b/lisp/vc/vc-rcs.el
index dc6f3c89159..fb57b2bbc6e 100644
--- a/lisp/vc/vc-rcs.el
+++ b/lisp/vc/vc-rcs.el
@@ -288,13 +288,13 @@ to the RCS command."
 			   (match-string 1))))))
 
 (defun vc-rcs-responsible-p (file)
-  "Return non-nil if RCS thinks it would be responsible for registering FILE."
+  "Return the directory if RCS thinks it would be responsible for FILE."
   ;; TODO: check for all the patterns in vc-rcs-master-templates
   (let ((dir (if (file-directory-p file)
 	         file
 	       (file-name-directory file))))
     (and (file-directory-p (expand-file-name "RCS" dir))
-         dir)))
+         (file-name-directory (expand-file-name "RCS" dir)))))
 
 (defun vc-rcs-receive-file (file rev)
   "Implementation of receive-file for RCS."
diff --git a/lisp/vc/vc-sccs.el b/lisp/vc/vc-sccs.el
index ef64cd9d580..0df70c8f232 100644
--- a/lisp/vc/vc-sccs.el
+++ b/lisp/vc/vc-sccs.el
@@ -212,7 +212,7 @@ to the SCCS command."
       (vc-sccs-do-command nil 0 "get" (vc-master-name file)))))
 
 (defun vc-sccs-responsible-p (file)
-  "Return non-nil if SCCS thinks it would be responsible for registering FILE."
+  "Return the directory if SCCS thinks it would be responsible for FILE."
   ;; TODO: check for all the patterns in vc-sccs-master-templates
   (or (and (file-directory-p
             (expand-file-name "SCCS" (file-name-directory file)))
diff --git a/lisp/vc/vc-src.el b/lisp/vc/vc-src.el
index 1c1a7b5d139..5a252c55cb2 100644
--- a/lisp/vc/vc-src.el
+++ b/lisp/vc/vc-src.el
@@ -242,11 +242,13 @@ This function differs from vc-do-command in that it invokes `vc-src-program'."
   (vc-src-command nil files "add"))
 
 (defun vc-src-responsible-p (file)
-  "Return non-nil if SRC thinks it would be responsible for registering FILE."
-  (file-directory-p (expand-file-name ".src"
-                                      (if (file-directory-p file)
-                                          file
-                                        (file-name-directory file)))))
+  "Return the directory if SRC thinks it would be responsible for FILE."
+  (let ((dir (expand-file-name ".src"
+                               (if (file-directory-p file)
+                                   file
+                                 (file-name-directory file)))))
+    (and (file-directory-p dir)
+         dir)))
 
 (defun vc-src-checkin (files comment &optional _rev)
   "SRC-specific version of `vc-backend-checkin'.
diff --git a/lisp/vc/vc.el b/lisp/vc/vc.el
index 45c09ae1c6a..bebd0946dee 100644
--- a/lisp/vc/vc.el
+++ b/lisp/vc/vc.el
@@ -220,7 +220,7 @@
 ;;
 ;; - responsible-p (file)
 ;;
-;;   Return non-nil if this backend considers itself "responsible" for
+;;   Return the directory if this backend considers itself "responsible" for
 ;;   FILE, which can also be a directory.  This function is used to find
 ;;   out what backend to use for registration of new files and for things
 ;;   like change log generation.  The default implementation always