New commands vc-print-change-log & vc-print-root-change-log

* lisp/vc/vc.el (vc--read-branch-to-log): Call
vc-deduce-fileset.  Don't wrap return value in a list.
(vc-print-fileset-branch-log, vc-print-root-branch-log): Adjust
calls to vc--read-branch-to-log.
(vc-print-change-log, vc-print-root-change-log):
New commands (bug#80037).
* etc/NEWS: Announce them.

etc/NEWS

@@ -2716,6 +2716,19 @@ View mode, copies to the kill ring the ID of the revision at point in
 the log entry.  If there are marked revisions, it copies the IDs of
 those, instead.
 
+---
+*** New commands 'vc-print-change-log' and 'vc-print-root-change-log'.
+These are just like 'vc-print-log' and 'vc-print-root-log' except that
+they have a different prefix argument that some users may prefer.
+With a prefix argument, these commands prompt for a branch, tag or other
+reference to a revision to log, and a maximum number of revisions to
+print.  If you find this prefix argument more useful, or more mnemonic,
+than the prefix arguments that 'vc-print-log' and 'vc-print-root-log'
+already have, consider replacing the default global bindings, like this:
+
+    (keymap-global-set "C-x v l" #'vc-print-change-log)
+    (keymap-global-set "C-x v L" #'vc-print-root-change-log)
+
 ---
 *** New command alias 'vc-restore' for 'vc-revert'.
 

lisp/vc/vc.el

@@ -3969,6 +3969,29 @@ shown log style is available via `vc-log-short-style'."
     (vc-print-log-internal (car fileset) (cadr fileset)
                            working-revision nil limit)))
 
+;;;###autoload
+(defun vc-print-change-log ()
+  "Show in another window the VC change history of the current fileset.
+With a \\[universal-argument] prefix argument, prompt for a branch \
+or revision to log
+instead of the working revision, and a number specifying the maximum
+number of revisions to show; the default is `vc-log-show-limit'.
+You can also use a numeric prefix argument to specify this.
+
+This is like `vc-print-log' but with an alternative prefix argument that
+some users might prefer for interactive usage."
+  (declare (interactive-only vc-print-log))
+  (interactive)
+  (if current-prefix-arg
+      (let ((branch
+             (vc--read-branch-to-log t))
+            (vc-log-show-limit
+             (if (equal current-prefix-arg '(4))
+                 (vc--read-limit)
+               (prefix-numeric-value current-prefix-arg))))
+        (vc-print-fileset-branch-log branch))
+    (vc-print-log)))
+
 ;;;###autoload
 (defun vc-print-root-log (&optional limit revision)
   "Show in another window VC change history of the current VC controlled tree.
@@ -4002,13 +4025,39 @@ with its diffs (if the underlying VCS backend supports that)."
       ;; the mode line isn't helpful.
       (setq vc-parent-buffer-name nil))))
 
-(defun vc--read-branch-to-log (&optional files)
+;;;###autoload
+(defun vc-print-root-change-log ()
+  "Show in another window the VC change history of the whole tree.
+With a \\[universal-argument] prefix argument, prompt for a branch \
+or revision to log
+instead of the working revision, and a number specifying the maximum
+number of revisions to show; the default is `vc-log-show-limit'.
+You can also use a numeric prefix argument to specify this.
+
+This is like `vc-root-print-log' but with an alternative prefix argument
+that some users might prefer for interactive usage."
+  (declare (interactive-only vc-print-root-log))
+  (interactive)
+  (if current-prefix-arg
+      (let ((branch
+             (vc--read-branch-to-log t))
+            (vc-log-show-limit
+             (if (equal current-prefix-arg '(4))
+                 (vc--read-limit)
+               (prefix-numeric-value current-prefix-arg))))
+        (vc-print-root-branch-log branch))
+    (vc-print-root-log)))
+
+(defun vc--read-branch-to-log (&optional fileset)
   "Read the name of a branch to log.
-FILES, if supplied, should be a list of file names."
-  (let ((branch (vc-read-revision "Branch to log: " files)))
+FILESET, if non-nil, means to pass the current VC fileset to
+`vc-read-revision'."
+  (let ((branch (vc-read-revision "Branch to log: "
+                                  (and fileset
+                                       (cadr (vc-deduce-fileset t))))))
     (when (string-empty-p branch)
       (user-error "No branch specified"))
-    (list branch)))
+    branch))
 
 ;;;###autoload
 (defun vc-print-fileset-branch-log (branch)
@@ -4021,7 +4070,7 @@ starting at that revision.  Tags and remote references also work."
   ;; used to prompt for a LIMIT argument like \\`C-x v l' has.  Though
   ;; now we have "Show 2X entries" and "Show unlimited entries" that
   ;; might be a waste of the prefix argument to this command.  --spwhitton
-  (interactive (vc--read-branch-to-log (cadr (vc-deduce-fileset t))))
+  (interactive (list (vc--read-branch-to-log t)))
   (let ((fileset (vc-deduce-fileset t)))
     (vc-print-log-internal (car fileset) (cadr fileset) branch t
                            (and (plusp vc-log-show-limit)
@@ -4035,7 +4084,7 @@ In addition to logging branches, for VCS for which it makes sense you
 can specify a revision ID instead of a branch name to produce a log
 starting at that revision.  Tags and remote references also work."
   ;; Prefix argument conserved; see previous command.  --spwhitton
-  (interactive (vc--read-branch-to-log))
+  (interactive (list (vc--read-branch-to-log)))
   (vc--with-backend-in-rootdir "VC branch log"
     (vc-print-log-internal backend (list rootdir) branch t
                            (and (plusp vc-log-show-limit)