From 214507c70f05935aac7cfa811b2e3a47335943fb Mon Sep 17 00:00:00 2001
From: "Richard M. Stallman" <rms@gnu.org>
Date: Thu, 16 Sep 1993 14:56:45 +0000
Subject: [PATCH] (font-lock-fontify-region): Don't add `font-lock' props.
 (font-lock-unfontify-region): Don't remove `font-lock' props.
 (font-lock-hack-keywords): Don't add `font-lock' props. Handle values other
 than t and nil for allow-overlap-p specially. (c-font-lock-keywords-1): Don't
 override how comments in #if... appear. Highlight text after #else or #endif.

---
 lisp/font-lock.el | 48 +++++++++++++++++++++++++++++++-----------------
 1 file changed, 31 insertions(+), 17 deletions(-)

diff --git a/lisp/font-lock.el b/lisp/font-lock.el
index 87a134f1e88..ae8d5764e5d 100644
--- a/lisp/font-lock.el
+++ b/lisp/font-lock.el
@@ -87,13 +87,17 @@
   "*The keywords to highlight.
 If this is a list, then elements may be of the forms:
 
-  \"string\"			  ; a regexp to highlight in the 
+  \"string\"			  ; A regexp to highlight in the 
 				  ;  `font-lock-keyword-face'.
-  (\"string\" . integer)  	  ; match N of the regexp will be highlighted
-  (\"string\" . face-name)	  ; use the named face
-  (\"string\" integer face-name)    ; both of the above
-  (\"string\" integer face-name t)  ; this allows highlighting to overlap
-				  ;  with already-highlighted regions.
+  (\"string\" . N)  	          ; Highlight subexpression N of the regexp.
+  (\"string\" . face-name)	  ; Use the named face
+  (\"string\" N face-name)        ; Both of the above
+  (\"string\" N face-name t)      ; This allows highlighting to override
+				  ;  already-highlighted regions.
+  (\"string\" N face-name keep)   ; This allows highlighting to occur
+				  ; even if some parts of what STRING matches
+				  ; are already highlighted--but does not alter
+				  ; the existing highlighting of those parts.
 
 These regular expressions should not match text which spans lines.
 While \\[font-lock-fontify-buffer] handles multi-line patterns correctly,
@@ -150,7 +154,6 @@ slow things down!")
 			(nth 3 (parse-partial-sexp beg (point)
 						   nil nil state))))
 	    (put-text-property beg (point) 'face font-lock-string-face)
-	    (put-text-property beg (point) 'font-lock t)
 	    (setq state (parse-partial-sexp beg (point) nil nil state))))
       ;; Likewise for a comment.
       (if (or (nth 4 state) (nth 7 state))
@@ -163,7 +166,6 @@ slow things down!")
 			(nth 3 (parse-partial-sexp beg (point)
 						   nil nil state))))
 	    (put-text-property beg (point) 'face font-lock-comment-face)
-	    (put-text-property beg (point) 'font-lock t)
 	    (setq state (parse-partial-sexp beg (point) nil nil state))))
       ;; Find each interesting place between here and END.
       (while (and (< (point) end)
@@ -193,7 +195,6 @@ slow things down!")
 			(skip-chars-backward " \t"))
 		    (error (goto-char end))))
 		(put-text-property beg (point) 'face font-lock-comment-face)
-		(put-text-property beg (point) 'font-lock t)
 		(setq state (parse-partial-sexp here (point) nil nil state)))
 	    (if (nth 3 state)
 		(let ((beg (match-beginning 0)))
@@ -201,7 +202,6 @@ slow things down!")
 			      (nth 3 (parse-partial-sexp here (point)
 							 nil nil state))))
 		  (put-text-property beg (point) 'face font-lock-string-face)
-		  (put-text-property beg (point) 'font-lock t)
 		  (setq state (parse-partial-sexp here (point) nil nil state))))
 	      ))
 	;; Make sure PREV is non-nil after the loop
@@ -265,8 +265,8 @@ slow things down!")
 ;;; Fontifying arbitrary patterns
 
 (defsubst font-lock-any-properties-p (start end)
-  (or (get-text-property start 'font-lock)
-      (let ((next (next-single-property-change start 'font-lock)))
+  (or (get-text-property start 'face)
+      (let ((next (next-single-property-change start 'face)))
 	(and next (< next end)))))
 
 (defun font-lock-hack-keywords (start end &optional loudly)
@@ -303,9 +303,19 @@ slow things down!")
 	(or s (error "expression did not match subexpression %d" match))
 	;; don't fontify this keyword if we're already in some other context.
 	(or (if allow-overlap-p nil (font-lock-any-properties-p s e))
-	    (progn
-	      (put-text-property s e 'face face)
-	      (put-text-property s e 'font-lock t))))
+	    (if (not (memq allow-overlap-p '(t nil)))
+		(save-excursion
+		  (goto-char s)
+		  (save-restriction
+		    (narrow-to-region s e)
+		    (while (not (eobp))
+		      (let ((next (next-single-property-change (point) 'face)))
+			(if (> next (point-max))
+			    (setq next (point-max)))
+			(if (not (get-text-property (point) 'face))
+			    (put-text-property (point) next 'face face))
+			(goto-char next)))))
+	      (put-text-property s e 'face face))))
       (if loudly (message "Fontifying %s... (regexps...%s)"
 			  (buffer-name)
 			  (make-string (setq count (1+ count)) ?.))))
@@ -399,7 +409,7 @@ This can take a while for large buffers."
 ;;; Various mode-specific information.
 
 (defun font-lock-set-defaults ()
-  "sets font-lock-keywords to something appropriate for this mode."
+  "Set `font-lock-keywords' to something appropriate for this mode."
   (setq font-lock-keywords
 	(cond ((eq major-mode 'lisp-mode)	lisp-font-lock-keywords)
 	      ((eq major-mode 'emacs-lisp-mode)	lisp-font-lock-keywords)
@@ -482,7 +492,11 @@ This does a lot more highlighting.")
       font-lock-function-name-face)
     ;;
     ;; fontify other preprocessor lines.
-    '("^#[ \t]*\\(if\\|ifn?def\\)[ \t]+\\([^\n]+\\)"
+    '("^#[ \t]*\\(if\\)[ \t]+\\([^\n]+\\)"
+      2 font-lock-function-name-face keep)
+    '("^#[ \t]*\\(endif\\|else\\)[ \t]+\\([^\n]+\\)"
+      2 font-lock-function-name-face keep)
+    '("^#[ \t]*\\(ifn?def\\)[ \t]+\\([^ \t\n]+\\)"
       2 font-lock-function-name-face t)
     ;;
     ;; fontify the filename in #include <...>
-- 
2.11.4.GIT