* lisp/subr.el: (string-common-prefix): New function.

* etc/NEWS:
* doc/lispref/strings.texi:
* doc/lispref/minibuf.texi:
* lisp/emacs-lisp/shortdoc.el:
Documentation.

Previously, 'quit' could cause remote endpoints to never get a
reply and thus sometimes hang.  Ensure we always reply.  Also,
give the application a chance to signal jsonrpc-error with the
served code=32000, meaning "no error".

* doc/lispref/text.texi (JSONRPC Overview): Rework section on
request dispatchers.

* lisp/jsonrpc.el (jsonrpc-connection-receive): Rework.

The info returned from `garbage-collect` is really handy to
track the evolution of the heap size, but sadly it's available only
at the cost of running a full GC, which has two big downsides:
it's slow, it affects what we're measuring, and it can't be used
in `post-gc-hook`.
So, this patch makes it available without running the GC.

* src/alloc.c (Fgarbage_collect_heapsize): New function, extracted from
`Fgarbage_collect`.
(Fgarbage_collect): Use it.
(syms_of_alloc): defsubr it.

* doc/lispref/internals.texi (Garbage Collection): Extract
documentation for it from that of `garbage-collect`.

* doc/lispref/internals.texi (Module Values, C Integer Types):
Mention that the example assumes Emacs was built with the
GMP library, not with mini-gmp.  Mention stdckdint.h for
integer overflow checking, and mention Emacs integers
for values outside machine range.

* lisp/vc/vc-git.el (vc-git--current-branch): Rename to ...
(vc-git-working-branch): ... this.  All uses changed.
(vc-git-trunk-or-topic-p, vc-git-topic-outgoing-base):
* lisp/vc/vc-hg.el (vc-hg--working-branch, vc-hg-working-branch)
(vc-hg-trunk-or-topic-p, vc-hg-topic-outgoing-base):
* lisp/vc/vc-hooks.el (vc--safe-branch-regexps-p):
* lisp/vc/vc.el (vc-default-working-branch)
(vc-default-trunk-or-topic-p, vc--match-branch-name-regexps)
(vc--outgoing-base, vc--outgoing-base-mergebase)
(vc--maybe-read-outgoing-base): New functions.
(vc-diff-outgoing-base): Call vc--outgoing-base-mergebase.
(vc-root-diff-outgoing-base, vc-diff-outgoing-base): Use
vc--maybe-read-outgoing-base in interactive specification.
(working-branch, trunk-or-topic-p, topic-outgoing-base): New
specifications for backend functions.
(vc-trunk-branch-regexps, vc-topic-branch-regexps): New
variables.
* .dir-locals.el: Commented entries for the new variables.
* test/lisp/vc/vc-tests/vc-test-misc.el
(vc-test-match-branch-name-regexps): New test.
* doc/emacs/vc1-xtra.texi (Outstanding Changes): Document the
new functionality.

Previously, if 'calc-string-maximum-character' wasn't a valid
character 'math-vector-is-string' would throw an error in the
comparison, leading to an incomplete display of the stack and a
cryptic error message.  Instead, have 'math-vector-is-string'
return nil, which effectively disables the display of strings.
Refines feature introduced in bug#78528.
* doc/misc/calc.texi (Customizing Calc): Update description of
behavior for invalid 'calc-string-maximum-character'.
* lisp/calc/calccomp.el (math-vector-is-string): Return nil when
'calc-string-maximum-character' doesn't represent a character.
* test/lisp/calc/calc-tests.el (calc-math-vector-is-string): Correct
and simplify tests.

* doc/misc/dbus.texi (Top): Add "Inhibitor Locks" submenu.
Remove trailing period from chapter and section titles.
(Inhibitor Locks): New node.

* etc/NEWS: New D-Bus functions to support systemd inhibitor locks.
Presentational fixes and improvements.

* src/dbusbind.c (xd_registered_inhibitor_locks): New variable.
(Fdbus_make_inhibitor_lock, Fdbus_close_inhibitor_lock)
(Fdbus_registered_inhibitor_locks): New DEFUNs.  (Bug#79963)
(syms_of_dbusbind_for_pdumper): Initialize
`xd_registered_inhibitor_locks'.
(syms_of_dbusbind): Declare subroutines
`Sdbus_make_inhibitor_lock', `Sdbus_close_inhibitor_lock' and
`Sdbus_registered_inhibitor_locks'.  Declare symbol `Qdbus_call_method'.
staticpro `xd_registered_inhibitor_locks'.

* test/lisp/net/dbus-tests.el (dbus--test-systemd-service)
(dbus--test-systemd-path, dbus--test-systemd-manager-interface):
New defconsts.
(dbus-test10-inhibitor-locks): New test.