From: Alan Mackenzie Date: Sat, 9 Nov 2019 12:09:30 +0000 (+0000) Subject: CC Mode. Allow fontification of "wrong" style comments with warning face. X-Git-Tag: emacs-27.0.90~689 X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=b293aa91bcc7f553ffbc6c67027f3c86d06ffbd7;p=emacs.git CC Mode. Allow fontification of "wrong" style comments with warning face. This fixes bug #4192. * etc/NEWS: Add a new entry. * lisp/progmodes/cc-defs.el (c-font-lock-flush): New macro. * lisp/progmodes/cc-cmds.el (c-toggle-comment-style): On toggling the comment style, invoke c-font-lock-flush when c-mark-wrong-style-of-comment is non-nil, to cause that marking to be done instead on the other style of comment. * lisp/progmodes/cc-fonts.el (c-maybe-font-lock-wrong-style-comments): New function. (c-cpp-matchers): Call c-maybe-font-lock-wrong-style-comments when appropriate. * lisp/progmodes/cc-vars.el (c-mark-wrong-style-of-comment): New customizable option. * doc/misc/cc-mode.texi (top level, Indentation Commands, Guessing the Style, Custom Macros): For some opening quote marks, correct '' to ``. (Minor Modes): Add an xref to the new page "Wrong Comment Style" in a footnote. (Wrong Comment Style): New page. --- diff --git a/doc/misc/cc-mode.texi b/doc/misc/cc-mode.texi index 217261090bf..a802ca9886f 100644 --- a/doc/misc/cc-mode.texi +++ b/doc/misc/cc-mode.texi @@ -669,7 +669,7 @@ expression, to some statements, or perhaps to whole functions, the syntactic recognition can be wrong. @ccmode{} manages to figure it out correctly most of the time, though. -Some macros, when invoked, ''have their own semicolon''. To get the +Some macros, when invoked, ``have their own semicolon''. To get the next line indented correctly, rather than as a continuation line, @xref{Macros with ;}. @@ -1149,7 +1149,9 @@ find useful while writing new code or editing old code: @table @asis @item comment style This specifies whether comment commands (such as @kbd{M-;}) insert -block comments or line comments. +block comments or line comments@footnote{You can emphasize +non-default style comments in your code by giving their delimiters +@code{font-lock-warning-face}. @xref{Wrong Comment Style}.}. @item electric mode When this is enabled, certain visible characters cause reformatting as they are typed. This is normally helpful, but can be a nuisance when @@ -1866,6 +1868,7 @@ sections apply to the other languages. * Font Locking Preliminaries:: * Faces:: * Doc Comments:: +* Wrong Comment Style:: * Misc Font Locking:: * AWK Mode Font Locking:: @end menu @@ -2069,7 +2072,7 @@ since those aren't syntactic errors in themselves. @comment !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! -@node Doc Comments, Misc Font Locking, Faces, Font Locking +@node Doc Comments, Wrong Comment Style, Faces, Font Locking @comment node-name, next, previous, up @section Documentation Comments @cindex documentation comments @@ -2149,7 +2152,29 @@ If you add support for another doc comment style, please consider contributing it: send a note to @email{bug-cc-mode@@gnu.org}. @comment !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! -@node Misc Font Locking, AWK Mode Font Locking, Doc Comments, Font Locking +@node Wrong Comment Style, Misc Font Locking, Doc Comments, Font Locking +@comment node-name, next, previous, up +@section Marking ``Wrong'' style comments +@comment !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! + +Most languages supported by @ccmode{} have two styles of comments, +namely block comments and line comments. Your project may have such a +strong preference for one of them, that you wish ``wrong'' style +comments to be clearly marked. + +You can get @ccmode{} to do this by setting the default comment style, +if necessary, (@pxref{Minor Modes}) and setting the customizable +option @code{c-mark-wrong-style-of-comment} to non-@code{nil}. + +@defvar c-mark-wrong-style-of-comment +@vindex mark-wrong-style-of-comment (c-) +When this customizable option is non-@code{nil}, comment delimiters +which aren't of the default style will be fontified with +@code{font-lock-warning-face}. +@end defvar + +@comment !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! +@node Misc Font Locking, AWK Mode Font Locking, Wrong Comment Style, Font Locking @comment node-name, next, previous, up @section Miscellaneous Font Locking @comment !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! @@ -2885,11 +2910,11 @@ should not be changed directly; use @code{c-add-style} instead. Instead of specifying a style, you can get @ccmode{} to @dfn{guess} your style by examining an already formatted code buffer. @ccmode{} -then determines the ''most frequent'' offset (@pxref{c-offsets-alist}) +then determines the ``most frequent'' offset (@pxref{c-offsets-alist}) for each of the syntactic symbols (@pxref{Indentation Engine Basics}) -encountered in the buffer, and the ''most frequent'' value of +encountered in the buffer, and the ``most frequent'' value of c-basic-offset (@pxref{Customizing Indentation}), then merges the -current style with these ''guesses'' to form a new style. This +current style with these ``guesses'' to form a new style. This combined style is known as the @dfn{guessed style}. To do this, call @code{c-guess} (or one of the other 5 guessing @@ -6927,7 +6952,7 @@ is @code{nil}, all lines inside macro definitions are analyzed as Because a macro can expand into anything at all, near where one is invoked @ccmode{} can only indent and fontify code heuristically. Sometimes it gets it wrong. Usually you should try to design your -macros so that they ''look like ordinary code'' when you invoke them. +macros so that they ``look like ordinary code'' when you invoke them. However, two situations are so common that @ccmode{} handles them specially: that is when certain macros needn't (or mustn't) be followed by a @samp{;}, and when certain macros (or compiler diff --git a/etc/NEWS b/etc/NEWS index 95d6b9b5bd4..61b9f933f15 100644 --- a/etc/NEWS +++ b/etc/NEWS @@ -2264,6 +2264,14 @@ file-local variable, you may need to update the value. *** Declare 'define-overload' and 'define-child-mode' as obsolete *** Rename several internal functions to use a ''mode-local-' prefix +** CC Mode + ++++ +*** You can now flag "wrong style" comments with font-lock-warning-face. +To do this, use c-toggle-comment-style, if needed, to set the desired +default comment style (block or line); then set the option +c-mark-wrong-style-of-comment to non-nil. + * New Modes and Packages in Emacs 27.1 diff --git a/lisp/progmodes/cc-cmds.el b/lisp/progmodes/cc-cmds.el index 9aa2019ae60..af2efb63fc3 100644 --- a/lisp/progmodes/cc-cmds.el +++ b/lisp/progmodes/cc-cmds.el @@ -391,6 +391,16 @@ This action does nothing when the mode only has one comment style." (if c-block-comment-flag (concat " " c-block-comment-ender) "")) + ;; If necessary, invert the sense of fontification of wrong style comments. + (when (and c-mark-wrong-style-of-comment + font-lock-mode + c-block-comment-starter + c-block-comment-ender) + (save-excursion + (save-restriction + (widen) + (goto-char (point-min)) + (c-font-lock-flush (point-min) (point-max))))) (c-update-modeline) (c-keep-region-active)) diff --git a/lisp/progmodes/cc-defs.el b/lisp/progmodes/cc-defs.el index e9a3e16db36..6a9371e6f19 100644 --- a/lisp/progmodes/cc-defs.el +++ b/lisp/progmodes/cc-defs.el @@ -219,6 +219,13 @@ This variant works around bugs in `eval-when-compile' in various `(cl-delete-duplicates ,cl-seq ,@cl-keys) `(delete-duplicates ,cl-seq ,@cl-keys)))) +(defmacro c-font-lock-flush (beg end) + "Declare the region BEG...END's fontification as out-of-date. +On XEmacs and older Emacsen, this refontifies that region immediately." + (if (fboundp 'font-lock-flush) + `(font-lock-flush ,beg ,end) + `(font-lock-fontify-region ,beg ,end))) + (defmacro c-point (position &optional point) "Return the value of certain commonly referenced POSITIONs relative to POINT. The current point is used if POINT isn't specified. POSITION can be diff --git a/lisp/progmodes/cc-fonts.el b/lisp/progmodes/cc-fonts.el index c27b70603ed..0daea8c84c9 100644 --- a/lisp/progmodes/cc-fonts.el +++ b/lisp/progmodes/cc-fonts.el @@ -95,6 +95,7 @@ ;; during compilation. (cc-bytecomp-defvar c-preprocessor-face-name) (cc-bytecomp-defvar c-reference-face-name) +(cc-bytecomp-defvar c-block-comment-flag) (cc-bytecomp-defun c-fontify-recorded-types-and-refs) (cc-bytecomp-defun c-font-lock-declarators) (cc-bytecomp-defun c-font-lock-objc-method) @@ -532,7 +533,12 @@ stuff. Used on level 1 and higher." (sws-depth (c-lang-const c-syntactic-ws-depth)) (nsws-depth (c-lang-const c-nonempty-syntactic-ws-depth))) - `(;; The stuff after #error and #warning is a message, so + `(;; Fontify "invalid" comment delimiters + ,@(when (and (c-lang-const c-block-comment-starter) + (c-lang-const c-line-comment-starter)) + `(c-maybe-font-lock-wrong-style-comments)) + + ;; The stuff after #error and #warning is a message, so ;; fontify it as a string. ,@(when (c-lang-const c-cpp-message-directives) (let* ((re (c-make-keywords-re 'appendable ; nil @@ -715,6 +721,59 @@ stuff. Used on level 1 and higher." (parse-partial-sexp end limit nil nil state 'syntax-table))) nil) +(defun c-maybe-font-lock-wrong-style-comments (limit) + ;; This function will be called from font-lock-for a region bounded by POINT + ;; and LIMIT, as though it were to identify a keyword for + ;; font-lock-keyword-face. It always returns NIL to inhibit this and + ;; prevent a repeat invocation. See elisp/lispref page "Search-based + ;; Fontification". + ;; + ;; This function fontifies "invalid" comment delimiters with + ;; `font-lock-warning-face'. A delimiter is "invalid" when + ;; `c-mark-wrong-style-of-comment' is non-nil, and the delimiter style is + ;; not the default specified by `c-block-comment-flag'. + (when c-mark-wrong-style-of-comment + (let* ((lit (c-semi-pp-to-literal (point))) + (s (car lit)) ; parse-partial-sexp state. + ) + ;; First, deal with and move out of any literal we start in. + (cond + ((null (cadr lit))) ; Not in a literal + ((eq (cadr lit) 'string) + (setq s (parse-partial-sexp (point) limit nil nil s 'syntax-table))) + ((and (not c-block-comment-flag) ; In an "invalid" block comment + (eq (cadr lit) 'c)) + (setq s (parse-partial-sexp (point) limit nil nil s 'syntax-table)) + ;; Font lock the block comment ender with warning face. + (when (not (nth 4 s)) + (c-put-font-lock-face (- (point) (length c-block-comment-ender)) + (point) font-lock-warning-face))) + (t ; In a line comment, or a "valid" block comment + (setq s (parse-partial-sexp (point) limit nil nil s 'syntax-table)))) + + (while (< (point) limit) + (setq s (parse-partial-sexp (point) limit nil nil s 'syntax-table)) + (cond + ((or (nth 3 s) ; In a string + (and (nth 4 s) ; In a comment + (eq (nth 7 s) ; Comment style + (if c-block-comment-flag + nil ; Block comment + 1)))) ; Line comment + ;; Move over a "valid" literal. + (setq s (parse-partial-sexp (point) limit nil nil s 'syntax-table))) + ((nth 4 s) ; In an invalid comment + ;; Fontify the invalid comment opener. + (c-put-font-lock-face (nth 8 s) (point) font-lock-warning-face) + ;; Move to end of comment or LIMIT. + (setq s (parse-partial-sexp (point) limit nil nil s 'syntax-table)) + ;; Fontify an invalid block comment ender, if that's what we have. + (when (and (not c-block-comment-flag) + (not (nth 4 s))) ; We're outside the comment + (c-put-font-lock-face (- (point) (length c-block-comment-ender)) + (point) font-lock-warning-face))))))) + nil) + (c-lang-defconst c-basic-matchers-before "Font lock matchers for basic keywords, labels, references and various other easily recognizable things that should be fontified before generic diff --git a/lisp/progmodes/cc-vars.el b/lisp/progmodes/cc-vars.el index 60ad42f24f4..273174e0413 100644 --- a/lisp/progmodes/cc-vars.el +++ b/lisp/progmodes/cc-vars.el @@ -1751,6 +1751,14 @@ variables.") c-macro-names-with-semicolon: %s" c-macro-names-with-semicolon)))))) +(defcustom c-mark-wrong-style-of-comment nil + "Fontify \"invalid\" comment delims with `font-lock-warning-face' if non-nil. +\"Invalid\" means a line comment when the default comment style (set by +`c-toggle-comment-style') is block, or a block comment otherwise." + :type 'boolean + :group 'c + :version 27.1) + (defvar c-file-style nil "Variable interface for setting style via File Local Variables. In a file's Local Variable section, you can set this variable to a