Announce recent changes in NEWS.org and bump version to 0.27.3

; Update copyright for 2024

; * sweep.texi (General Improvements): Fix typo

; Remove two unused local variables

* sweeprolog.el (sweeprolog--diagnostics-changes-beg)
(sweeprolog--diagnostics-changes-end): Unused, remove.
* sweeprolog.el (sweeprolog-diagnostic-function): Adapt.

; Fix error with documentation at point for atom non-terminals

* sweep.pl (explicit_args_/3): Check whether G0 is an atom.
* sweeprolog-tests.el (eldoc-dcg-atom): Test it.

Indentation fixups

Fix fullstop detection in presence of dot character literal

This fixes an issue where the character "0'." in a clause body would
confuse clause boundaries calculation.

* sweeprolog.el (sweeprolog-end-of-top-term): Make sure fullstop have
punctuation syntax class (otherwise it's part of a character literal).
* sweeprolog-tests.el (end-of-top-term-with-dot-char-literal): Test it

Fix top-level buffer to thread id association

* sweeprolog.el (sweeprolog-top-level-buffer): Fix thinko.
* sweeprolog-tests.el (backward-sexp-over-char-literal): New test.

Provide documentation for predicate at point in top-levels

; Fix error with documentation at point for nullary compounds

Announce recent changes in NEWS.org and bump version to 0.27.2

Improve hole highlighting in the Sweep top-level

* sweeprolog.el (sweeprolog-analyze-end-font-lock): Extract hole
highlighting code to...
(sweeprolog--highlight-holes): New function.
(sweeprolog-colourise-query): Use it.
(sweeprolog-fill-holes): New command.
(sweeprolog--fill-query-holes): New function.
(sweeprolog-top-level-mode): Use it to fill holes in query when
posting it.

* sweep.texi (Filling Holes): Document 'sweeprolog-fill-holes'.

; Add test for 'forward/backward-sexp' in strings

Adapt 'derived-mode-p' calls to Emacs 30.1 calling convention

Use a few more hook functions also in top-level buffers

* sweeprolog.el (sweeprolog-top-level-mode): Set
'forward-sexp-function', 'beginning-of-defun-function',
'end-of-defun-function' and 'syntax-propertize-function' hooks to
their Prolog-specific value that we already use in 'sweeprolog-mode'.

Respect 'syntax-table' text properties

Replace all usages of (char-syntax (char-before/after ...)) with
'syntax-after' calls, since the former doesn't take into account the
'syntax-table' text property that 'syntax-propertize-function' adds.
In particular, this fixes an issue with 'forward-sexp' over character
literals such as "0'c".

* sweeprolog.el (sweeprolog-syntax-propertize): Replace with...
(sweeprolog-syntax-propertize-function): New 'defconst'.
(sweeprolog-mode): Use it.
(sweeprolog--op-p, sweeprolog-syntax-class-at): New 'defsubst'.
(sweeprolog--parse-context, sweeprolog--completion-at-point)
(sweeprolog-next-token-boundaries, sweeprolog-last-token-boundaries)
(sweeprolog--forward-term, sweeprolog--backward-term)
(sweeprolog--precedence-at-point,sweeprolog-align-spaces)
(sweeprolog-indent-line): Respect 'syntax-table' text properties.

* sweeprolog-tests.el (backward-sexp-over-char-literal): Test it.

Fix docs for predicate at point in DCG bodies

* sweep.pl (sweep_short_documentation_body/9): Add special handling
for control constructs in DCG bodies.
* sweeprolog-tests.el (eldoc-dcg): New test.

Add a few missing CHR-specific faces and help messages

* sweeprolog.el (sweeprolog-deprecated):
(sweeprolog-delimiter):
(sweeprolog-pragma):
(sweeprolog-chr-type): New faces.
(sweeprolog-analyze-fragment-to-faces): Use them.
(sweeprolog-analyze-fragment-help-echo): Add 'help-echo' text for
CHR-specific term kinds.
(sweeprolog--help-echo-for-goal-functor): Shorten messages.

Announce recent changes in NEWS.org and bump version to 0.27.1

* sweeprolog.el (sweeprolog-read-predicate): Require match.

ADDED: in-buffer completions for Prolog flags

* sweep.pl (sweep_context_callable_arg/4): Report "flag" context.
(sweep_flags_collection/2): New predicate.
* sweeprolog.el (sweeprolog--flag-completion-at-point): New function.
(sweeprolog--atom-or-functor-completion-at-point): Use it.
* sweeprolog-tests.el (cap-flag-name): New test.
* sweep.texi (Code Completion): Update.

; Further optimize predicate completion at point

; * sweeprolog.el (-predicate-completion-candidates): Fix typo

Narrow to current query for top-level completion at point

* sweeprolog.el (sweeprolog-top-level-completion-at-point): New function.
(sweeprolog-top-level-mode): Use it.

Optimize predicate completion at point

* sweep.pl (sweep_heads_collection/2): Optimize for speed.  Also
report functor length and arity for each candidate to facilitate
faster sorting.
* sweeprolog.el (sweeprolog-init-args): Add '-O'.
(sweeprolog-predicate-completion-candidates): Improve sorting.

; Fix fresh variable naming in term replacement

; Exclude grammar rules from regular goal completion

* sweep.pl (sweep_heads_collection/2): Exclude DCG non-terminals when
completing a regular goal.

; Fix naming of implicit DCG arguments in completion candidates

* sweep.pl (predicate_argument_names/3): Make implicit arguments
appear as anonymous variables.

Announce recent changes in NEWS.org and bump version to 0.27.0

; Inhibit ElDoc messages for common Prolog control constructs

; * sweep.texi (Showing Prolog Docs): Reword.

; Silence syntax errors when rereading predicate modes term

Highlight current argument in ElDoc documentation messages

* sweep.pl (sweep_short_documentation/2): New predicate.
* sweeprolog.el (sweeprolog-predicate-modes-doc): Use it.

Use bespoke face for the ElDoc callback ':face' argument

* sweeprolog.el (sweeprolog-predicate-modes-doc): Use
'sweeprolog-predicate-indicator' face instead of
'font-lock-function-name-face'.

Announce recent changes in NEWS.org and bump version to 0.26.2

Handle SIGHUP in daemon mode when killing a tty top-level

When Emacs is running as a daemon, and deletes the process of a
top-level that uses a tty, the top-level receives SIGHUP.  But since
the top-level is a thread is the same process as Emacs itself, this
results in 'kill-emacs'.  To prevent this unfortunate outcome, set a
no-op handler for SIGHUP before deleting the top-level process and
restore the original handler afterwards.

* sweep.pl (sweep_nohup/2): New predicate.
* sweeprolog.el (sweeprolog-top-level-filter): New function.
(sweeprolog-top-level-buffer): Use it.

; * sweep.texi: Fix chapter description

Announce recent changes in NEWS.org and bump version to 0.26.1

Avoid possible race condition with tty top-level creation

* sweeprolog.el (sweeprolog-top-level-buffer): Create the top-level
thread before calling stty.

Setup Xref in 'sweeprolog-top-level-mode'

* sweeprolog.el (sweeprolog-top-level-mode): Add
'sweeprolog--xref-backend' to 'xref-backend-functions'.

; * sweep.texi (Code Completion): Fix typo.

Announce recent changes in NEWS.org and bump version to 0.26.0

ADDED: in-buffer completions for arithmetic functions

* sweep.pl (sweep_function_functors_collection/2)
(sweep_functions_collection/2): New predicates.
(sweep_context_callable_arg/4): Recognize arithmetic functions.

* sweeprolog.el (sweeprolog-arith-functor-completion-candidates)
(sweeprolog-arith-completion-candidates): New functions, used in...
(sweeprolog--atom-or-functor-completion-at-point): ...here.

* sweep.texi (Code Completion): Document arithmetic function completion.
* sweeprolog-tests.el: Test it.

ADDED: in-buffer completions for predicate options

* sweep.pl (sweep_option_functors_collection/2)
(sweep_options_collection/2)
(sweep_option_arguments_collection/2): New predicates.
(sweep_context_callable_arg/4): Recognize predicate options.

* sweeprolog.el (sweeprolog-option-functor-completion-candidates)
(sweeprolog-option-completion-candidates)
(sweeprolog-option-arg-completion-candidates): New functions, used in...
(sweeprolog--atom-or-functor-completion-at-point): ...here.

* sweep.texi (Code Completion): Document predicate options completion.
* sweeprolog-tests.el: Test it.

ADDED: in-buffer completions for source file specs

* sweep.pl (sweep_alias_source_file_name_collection/2)
(sweep_alias_source_file_name/4)
(sweep_source_file_name_collection/2)
(sweep_source_file_name/3)
(sweep_path_alias_collection/2)
(sweep_matching_path_alias/3): New predicates.
(sweep_context_callable_/3): Simplify, and recognize predicate
arguments that should be source file specifications.

* sweeprolog.el (sweeprolog-source-functor-completion-candidates)
(sweeprolog-alias-source-completion-candidates)
(sweeprolog-source-completion-candidates): New functions, used in...
(sweeprolog--atom-or-functor-completion-at-point): ...here.
(sweeprolog-electric-layout-post-self-insert-function)
(sweeprolog-context-menu-for-region)
(sweeprolog-maybe-extract-region-to-predicate): Adapt.

* sweep.texi (Code Completion): Document file spec completion.
* sweeprolog-tests.el: Test it.

Stop pty echo with 'stty' instead of 'comint-process-echoes'

* sweeprolog.el (sweeprolog-top-level-buffer): Call 'stty PTY -echo'
on GNU/Linux systems.

Revert "Set Prolog flag 'tty_control' to 'true' when using pty"

This reverts commit d70195ede30df33098f58cc6ba5fd19c26495055.

Announce recent changes in NEWS.org and bump version to 0.25.5

Expand Top-level documentation

* sweep.texi (Top-level Interaction): New section, replaces...
(Top-level Completion): Remove.
(The Prolog Top-level): Update menu and document ANSI
escape sequence handling.

Emit highlighted messages in the top-level

* sweep.pl: Ensure 'library(ansi_term)' gets loaded.
(sweep_top_level_client/4): Set the flag 'verbose' to 'normal' in
order to enable informational messages, and set 'color_term' to 'true'
to enable highlighting when using a pty.

Set Prolog flag 'tty_control' to 'true' when using pty

When 'sweeprolog-top-level-use-pty' is non-nil, let the Prolog
top-level thread know that it controls the tty.  This affects some
aspects of the top-level interaction, namely in the presence of choice
points.  A significant benefit is that Prolog ensures that the tty
does not echo input, so we can stop setting 'comint-process-echoes'
which had the adverse effect of blocking Emacs when output stalls on
non-echoing terminals.

* sweep.pl (sweep_top_level_client/3): Become
'sweep_top_level_client/4'.  New argument says whether the top-level
controls the tty.
(sweep_top_level_pty_client/1,sweep_top_level_server_loop_/2): Adjust.
* sweeprolog.el (sweeprolog-top-level-buffer): Stop setting
'comint-process-echoes'.
(sweeprolog-top-level--post-self-insert-function): When using a tty,
send single character responses directly and assume that the top-level
echoes them back.

; * sweep.texi: Fix typo

* sweep.texi (Things To Do): Add new to-do items

; Adapt tests following last change

Sort predicate completion candidates by functor length

* sweeprolog.el (sweeprolog-predicate-completion-sort): New function.
(sweeprolog-predicate-completion-candidates): Use it as
`display-sort-function`.

Announce recent changes in NEWS.org and bump version to 0.25.4

; Improve detection of unsafe goal extraction

* sweep.pl (sweep_extract_goal_update_safety/4): Adjust.
* sweeprolog-tests.el: Add more tests.

Fix extracting goals in right associative operator chains

* sweep.pl (push_assoc_arg/9): New helper predicate.
(sweep_extract_goal_term/21): Recognize and correctly handle right
associative operator chains.
(sweep_extract_goal_update_clause_string/7): Fix handling of nested
disjunctions.
* sweeprolog-tests.el: Add more goal extraction tests.
* sweeprolog.el (sweeprolog-extract-region-to-predicate): Add missing
call to 'format'.

Announce recent changes in NEWS.org and bump version to 0.25.3

; Fix excluding new predicate body from replacement after extraction

ENHANCED: Improve 'sweeprolog-extract-region-to-predicate'

Teach 'sweeprolog-extract-region-to-predicate' about existentially
quantified goals and lambda terms.

* sweep.pl (sweep_term_variable_names/2): Remove from export list.
* sweep.pl (sweep_extract_goal/2): New public predicate.
* sweeprolog.el (sweeprolog-extract-region-to-predicate): Use it.
* sweeprolog-tests.el: Test it.
* sweep.texi (Extract Goal): Update documentation.

; Improve user option docstring

* sweeprolog.el
(sweeprolog-query-replace-term-include-match-function): Improve docstring.

; * sweeprolog.el (sweeprolog-query-replace-term): Update comment

; Remove unused function 'sweeprolog-token-boundaries'

; New helper predicate 'pos_bounds/3'

; Fix precedence calculation for unary operator arguments

; Recognize ext-quantified goal positions as callable

; Add missing ':type' for 'sweeprolog-top-level-use-pty'

; Silence some byte-complier warnings

; Fix off-by-one in end of next token position for parentheses

* sweeprolog.el (sweeprolog-next-token-boundaries): Return correct end
of token position for parentheses.

* sweeprolog-tests.el (up-list): New test.

; Avoid relying on 'diff-mode' faces

* sweeprolog.el (sweeprolog-query-replace-term-prompt-old)
(sweeprolog-query-replace-term-prompt-new): New faces.
(sweeprolog-query-replace-term): Use them instead of 'diff-mode'
faces.

; Fix filtering of the just created body when extracting goal

* sweeprolog (sweeprolog-extract-region-to-predicate): When searching
and replacing other goals subsumed by the extracted goal, use a more
robust check to filter out the newly created body term from the search
matches.

; (sweep_replace_term_r/12): Fix qualified head classification

; (sweep_replace_update_state/7): Fix SSU guard classification

Announce recent changes in NEWS.org and bump version to 0.25.2

Extract subsumed goals when extracting goal to predicate

Extend 'sweeprolog-extract-region-to-predicate' with the ability to
replace other goals in the current buffer that are subsumed by the
extracted goal with calls to the predicate this command creates.
'sweeprolog-extract-region-to-predicate' now does this when it is
called with a prefix argument.  Also make
'sweeprolog-insert-term-dwim' propagate the prefix argument to
functions in 'sweeprolog-insert-term-functions'.

* sweeprolog.el (sweeprolog-insert-term-dwim): Add ARG argument and
pass it to functions listed...
(sweeprolog-insert-term-functions): ...here.  Adjust docstring.
(sweeprolog-maybe-insert-next-clause)
(sweeprolog-maybe-define-predicate)
(sweeprolog-maybe-extract-region-to-predicate): Adjust accordingly.
(sweeprolog-default-new-predicate-location): Go to end of line in case
there's a comment on the last line of the current predicate
definition.
(sweeprolog-query-replace-term-include-match-function): New variable.
(sweeprolog-query-replace-term): Use it.
(sweeprolog-extract-region-to-predicate): Add ALL argument.  When
non-nil, suggest replacing all goals in the buffer that are subsumbed
by the extracted goal with calls to the newly defined predicate.

; Improve documentation about shutting down Prolog

* sweeprolog.el (sweeprolog-shutdown): Tweak and make interactive.
* sweep.texi (Initialization): Document it, reorganize.

; Documentation fixes

* sweep.texi (Top, Editing Prolog Code): Mention "Term Replace" in
menus.
(Main Features, Architecture, Alternatives): Mark as sections rather
than chapters.

Announce recent changes in NEWS.org and bump version to 0.25.1

ADDED: new command 'sweeprolog-query-replace-term'

This patch extends the Term Search infrastructure to support
search-and-replace operations.  Namely, we replace the predicate
'sweep_term_search/2' with a new predicate 'sweep_term_replace/2' that
subsumes the functionality of the former.  The command
'sweeprolog-term-search' is greatly simplified and adjusted to work
with this new predicate, and we introduce a new command,
'sweeprolog-query-replace-term', that exposes the new
search-and-replace facility of 'sweep_term_replace/2' in an
interactive UI inspired by 'query-replace'.

* sweep.pl (sweep_term_search/2): Remove in favor of...
(sweep_term_replace/2): New predicate.
* sweeprolog.el: (sweeprolog-term-replace-edits): New function.
(sweeprolog-term-search): Rewrite.
(sweeprolog-term-search-last-search)
(sweeprolog-term-search-overlays)
(sweeprolog-term-search-repeat-count)
(sweeprolog-term-search-repeat-backward)
(sweeprolog-term-search-repeat-forward)
(sweeprolog-term-search-abort)
(sweeprolog-term-search-in-buffer)
(sweeprolog-term-search-next)
(sweeprolog-term-search-map): Remove, unused.
(sweeprolog-query-replace-term): New command.
(sweeprolog-mode-map): Bind it.
* sweeprolog-tests.el (term-search)
* sweep.texi (Term Search): Adjust.
(Term Replace): New section.

Announce recent changes in NEWS.org and bump version to 0.25.0

; * sweeprolog.el: Add docstrings for recently added functions

Set 'comint-process-echoes' for top-levels that use a tty

Improve top-level input fontification

Improve top-level threads management and cleanup

* sweep.pl (sweep_top_level_thread_buffer/2): Remove predicate.
(sweep_top_level_threads/2): Remove in favor of...
(sweep_list_threads/2): New predicate.
(sweep_accept_top_level_client/2)
(sweep_top_level_start_pty/2): Return new thread id.
(sweep_cleanup_threads/0,2)
(sweep_create_thread/2,3)
(sweep_thread_start/0)
(sweep_thread_at_exit/0)
(sweep_supervisor_start/1)
(sweep_supervisor_loop/1)
(sweep_kill_thread/2)
(sweep_cleanup_thread/1): New predicates.

* sweeprolog.el (sweeprolog-init): Arrange for Sweep to shutdown
gracefully when Emacs is killed.
(sweeprolog-maybe-kill-top-levels)
(sweeprolog-maybe-shutdown)
(sweeprolog-shutdown)
(sweeprolog-top-level-maybe-delete-process)
(sweeprolog-top-level-delete-process): New functions.
(sweeprolog-restart)
(sweeprolog-top-level-buffer): Adapt.
(sweeprolog-top-level--populate-thread-id): Remove function.

Check that top-level thread is alive when signaling it

* sweeprolog.el (sweeprolog-top-level-signal-current): Delete stale
pty "process" when trying to signal a top-level thread that has
already exited.

; Don't refuse to kill top-level buffer with deleted process

; Fix error on Emacs 27 with no 'font-lock-keywords'

ENHANCED: Support pty top-level communication instead of TCP

Add the ability for top-level buffers to communicate with their
backing threads via pty instead of a local TCP connection.  This is
controlled by a new user option, enabled by default on systems where
Emacs can creates a pty.

* sweep.pl (sweep_top_level_start_pty/2): New predicate.
* sweeprolog.el (sweeprolog-top-level-use-pty): New user option.
(sweeprolog-top-level-buffer): Use it.
* sweep.texi (The Prolog Top-level): Document it.

Provide basic 'prettify-symbols-alist' in Sweep Prolog mode

* sweeprolog.el (sweeprolog-mode): set a local value for
'prettify-symbols-alist' that renders the neck operator as a unicode
left arrow.

Support Prettify Symbols and similar minor modes

* sweeprolog.el (sweeprolog-analyze-some-terms): Call
'font-lock-fontify-keywords-region' to support minor modes that
rely on 'font-lock-keywords'.

; * sweeprolog.el (sweeprolog-hole): Avoid increasing text size

; * sweep.texi (Extract Goal): Improve indexing

Announce recent changes in NEWS.org and bump version to 0.24.1

Only extract goals to separate predicates, not data terms

* sweeprolog.el (sweeprolog-context-menu-for-region)
(sweeprolog-maybe-extract-region-to-predicate): Check that the region
starts in a callable position.
(sweeprolog-extract-region-to-predicate): Reanalyze the buffer as a
last step.
* sweep.texi: Adjust.

Only enable right-click actions on region when click is in region

* sweeprolog.el (sweeprolog-context-menu-region-beg-at-click)
(sweeprolog-context-menu-region-end-at-click): New variables.
(sweeprolog-context-menu-function): Let-bind them.
(sweeprolog-context-menu-for-region): Use them to reliably check that
click is actually inside the selected region.

; * sweep.texi: Minor improvements

; * sweep.texi (Extract Goal): Fix typos

; * sweep.texi: Update menus

Announce recent changes in NEWS.org and bump version to 0.24.0