* lisp/textmodes/fill.el (fill-region-as-paragraph-semlf): Add function
to fill a region using semantic linefeeds as if it were a single
paragraph.
(fill-paragraph-semlf): Add function to fill paragraph using semantic
linefeeds.
* test/lisp/textmodes/fill-tests.el
(fill-test-fill-region-as-paragraph-semlf)
(fill-test-fill-paragraph-semlf)
(fill-test-fill-paragraph-semlf-fill-paragraph-function)
(fill-test-fill-paragraph-semlf-justify)
(fill-test-fill-paragraph-semlf-sentence-end-double-space)
(fill-test-fill-paragraph-semlf-fill-column)
(fill-test-fill-paragraph-semlf-punctuation-marks)
(fill-test-fill-paragraph-semlf-twice)
(fill-test-fill-paragraph-semlf-fill-prefix)
(fill-test-fill-paragraph-semlf-indented-block)
(fill-test-fill-paragraph-semlf-revert)
(fill-test-fill-paragraph-semlf-emacs-lisp-mode)
(fill-test-fill-paragraph-semlf-c-mode)
(fill-test-fill-paragraph-semlf-org-mode)
(fill-test-fill-paragraph-semlf-markdown-mode): Add tests.
* test/lisp/textmodes/fill-resources/semlf-c-mode.erts:
* test/lisp/textmodes/fill-resources/semlf-emacs-lisp-mode.erts:
* test/lisp/textmodes/fill-resources/semlf-fill-column.erts:
* test/lisp/textmodes/fill-resources/semlf-fill-paragraph-function.erts:
* test/lisp/textmodes/fill-resources/semlf-fill-prefix.erts:
* test/lisp/textmodes/fill-resources/semlf-fill-region-as-paragraph.erts:
* test/lisp/textmodes/fill-resources/semlf-indented-block.erts:
* test/lisp/textmodes/fill-resources/semlf-justify.erts:
* test/lisp/textmodes/fill-resources/semlf-markdown-mode.erts:
* test/lisp/textmodes/fill-resources/semlf-org-mode.erts:
* test/lisp/textmodes/fill-resources/semlf-punctuation-marks.erts:
* test/lisp/textmodes/fill-resources/semlf-revert.erts:
* test/lisp/textmodes/fill-resources/semlf-sentence-end-double-space.erts:
* test/lisp/textmodes/fill-resources/semlf-twice.erts:
* test/lisp/textmodes/fill-resources/semlf.erts: Add test data. (Bug#78561)