38fec86281e ; Improve the documentation of 'slice' display spec (bug#...
3f05b455f7e ; * src/editfns.c (Fmessage): Mention 'inhibit-message' (...

* src/editfns.c (Freplace_region_contents): Redo slightly to
pacify gcc -Wclobbered, by hoisting the eassume out of SCHARS and
into the caller later, where it’ll do more good anyway.

Swap the role of `replace-region-contents` and `replace-buffer-contents`,
so `replace-region-contents` is the main function, implemented in C,
and `replace-buffer-contents` is a mere wrapper (marked as obsolete).
Also remove the need to rely on narrowing and on describing the
new text as a function.
Finally, allow MAX-SECS==0 to require a cheap replacement, and
add an INHERIT argument.

* src/editfns.c: Include `coding.h`.
(Freplace_region_contents): Rename from `Freplace_buffer_contents`.
Change calling convention to that of `replace-region-contents`.
Add more options for the SOURCE argument.  Add INHERIT argument.
Skip the costly algorithm if MAX-SECS is 0.
* src/insdel.c (replace_range): Allow NEW to be a buffer.

* lisp/subr.el (replace-buffer-contents): New implementation.
* lisp/emacs-lisp/subr-x.el (replace-region-contents): Delete.

* doc/lispref/text.texi (Replacing): Document new API for
`replace-region-contents`.  Remove documentation of
`replace-buffer-contents`.

* test/src/editfns-tests.el (replace-buffer-contents-1)
(replace-buffer-contents-2, replace-buffer-contents-bug31837):
Use `replace-region-contents`.
(editfns--replace-region): Delete.
(editfns-tests--replace-region): Use `replace-region-contents`.
Adds tests for new types of SOURCE args.

Use `replace_range` rather than `delete+insert`.

* src/insdel.c (replace_range): Allow NEW to specify a chunk
of buffer text.
* src/editfns.c (Freplace_buffer_contents): Use it.
* test/src/editfns-tests.el (replace-buffer-contents-1): Remove
incorrect check which happened to succeed because point was not
preserved carefully enough.  Make the replacement text share a bit
more content to make the test a bit more strict.
(editfns-tests--replace-region): Doesn't fail any more.

* src/lisp.h (replace_range):
* src/insdel.c (replace_range): Delete argument `markers`, always true.
* src/editfns.c (Ftranslate_region_internal):
* src/cmds.c (internal_self_insert):
* src/search.c (Freplace_match): Adjust callers accordingly.

This test fails, sadly, because `replace-buffer-contents` is not
careful enough to something like `replace_range`.

When `len1_byte == len2_byte`, the code presumed that len1==len2
as well in its handling of text-properties.  Fix that case.
While at it, try and reduce code duplication by hoisting common
code out of `if`s, and throw away the optimization for `len_mid == 0`
which only saved 3 trivial function calls.

* src/editfns.c (Ftranspose_regions): Shuffle the code a bit.

* test/src/editfns-tests.el (editfns-tests--transpose-equal-but-not):
New test.

* src/insdel.c (replace_range): Merge last arg, with `prepare`.
Rename `prepare` to `run-mode-hooks`.
* src/lisp.h (replace_range): Adjust accordingly.
* src/editfns.c (Ftranslate_region_internal):
* src/cmds.c (internal_self_insert):
* src/search.c (Freplace_match): Adjust callers.

This code was missed back in 2000 (commit 1b16afa45bb6).