CC Mode: Fontify declarators properly when, e.g., a jit-lock chunk begins

inside a declaration.  Changed cc-engine.el, cc-langs.el, cc-fonts.el.

4 files changed, 69 insertions, 4 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index f320398975c..0ea3d94a01f 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,3 +1,19 @@
+2011-07-18  Alan Mackenzie  <acm@muc.de>
+
+        Fontify declarators properly when, e.g., a jit-lock chunk begins
+        inside a declaration.
+
+        * progmodes/cc-langs.el (c-symbol-chars): Correct a typo.
+
+        * progmodes/cc-fonts.el (c-font-lock-enclosing-decls): New
+        function.
+        (c-complex-decl-matchers): Insert reference to
+        c-font-lock-enclosing-decls.
+
+        * progmodes/cc-engine.el (c-backward-single-comment):
+        (c-backward-comments): Bind open-paren-in-column-0-is-defun-start
+        to nil around calls to (forward-comment -1).
+
 2011-07-17  Lars Magne Ingebrigtsen  <larsi@gnus.org>
 
         * image.el (put-image): Doc typo fix.
diff --git a/lisp/progmodes/cc-engine.el b/lisp/progmodes/cc-engine.el
index 38f66b4504e..a6fd28be21d 100644
--- a/lisp/progmodes/cc-engine.el
+++ b/lisp/progmodes/cc-engine.el
@@ -1301,12 +1301,13 @@ This function does not do any hidden buffer changes."
       ;; same line.
       (re-search-forward "\\=\\s *[\n\r]" start t)
 
-      (if (if (forward-comment -1)
+      (if (if (let (open-paren-in-column-0-is-defun-start) (forward-comment -1))
               (if (eolp)
                   ;; If forward-comment above succeeded and we're at eol
                   ;; then the newline we moved over above didn't end a
                   ;; line comment, so we give it another go.
-                  (forward-comment -1)
+                  (let (open-paren-in-column-0-is-defun-start)
+                    (forward-comment -1))
                 t))
 
           ;; Emacs <= 20 and XEmacs move back over the closer of a
@@ -1333,7 +1334,8 @@ comment at the start of cc-engine.el for more info."
             ;; return t when moving backwards at bob.
             (not (bobp))
 
-            (if (forward-comment -1)
+            (if (let (open-paren-in-column-0-is-defun-start)
+                  (forward-comment -1))
                 (if (looking-at "\\*/")
                     ;; Emacs <= 20 and XEmacs move back over the
                     ;; closer of a block comment that lacks an opener.
diff --git a/lisp/progmodes/cc-fonts.el b/lisp/progmodes/cc-fonts.el
index 600bbc76e9a..0500d48ddbc 100644
--- a/lisp/progmodes/cc-fonts.el
+++ b/lisp/progmodes/cc-fonts.el
@@ -1346,6 +1346,50 @@ casts and declarations are fontified.  Used on level 2 and higher."
       (c-font-lock-declarators limit t nil)))
   nil)
 
+(defun c-font-lock-enclosing-decls (limit)
+  ;; Fontify the declarators of (nested) declarations we're in the middle of.
+  ;; This is mainly for when a jit-lock etc. chunk starts inside the brace
+  ;; block of a struct/union/class, etc.
+  ;; 
+  ;; 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".
+  (let* ((paren-state (c-parse-state))
+         (start (point))
+         decl-context bo-decl in-typedef type-type ps-elt)
+
+    ;; First, are we actually in a "local" declaration?
+    (setq decl-context (c-beginning-of-decl-1)
+          bo-decl (point)
+          in-typedef (looking-at c-typedef-key))
+    (if in-typedef (c-forward-token-2))
+    (when (and (eq (car decl-context) 'same)
+               (< bo-decl start))
+      ;; Are we genuinely at a type?
+      (setq type-type (c-forward-type t))
+      (if (and type-type
+               (or (not (eq type-type 'maybe))
+                   (looking-at c-symbol-key)))
+          (c-font-lock-declarators limit t in-typedef)))
+
+    ;; Secondly, are we in any nested struct/union/class/etc. braces?
+    (while paren-state
+      (setq ps-elt (car paren-state)
+            paren-state (cdr paren-state))
+      (when (and (atom ps-elt)
+                 (eq (char-after ps-elt) ?\{))
+        (goto-char ps-elt)
+        (setq decl-context (c-beginning-of-decl-1)
+              in-typedef (looking-at c-typedef-key))
+        (if in-typedef (c-forward-token-2))
+        (when (looking-at c-opt-block-decls-with-vars-key)
+          (goto-char ps-elt)
+          (when (c-safe (c-forward-sexp))
+            (c-forward-syntactic-ws)
+            (c-font-lock-declarators limit t in-typedef)))))))
+        
 (c-lang-defconst c-simple-decl-matchers
   "Simple font lock matchers for types and declarations.  These are used
 on level 2 only and so aren't combined with `c-complex-decl-matchers'."
@@ -1452,6 +1496,9 @@ on level 2 only and so aren't combined with `c-complex-decl-matchers'."
       ;; Fontify all declarations, casts and normal labels.
       c-font-lock-declarations
 
+      ;; Fontify declarators when POINT is within their declaration.
+      c-font-lock-enclosing-decls
+
       ;; Fontify angle bracket arglists like templates in C++.
       ,@(when (c-lang-const c-recognize-<>-arglists)
           `(c-font-lock-<>-arglists))
diff --git a/lisp/progmodes/cc-langs.el b/lisp/progmodes/cc-langs.el
index a6459e1724f..9ce23a080d6 100644
--- a/lisp/progmodes/cc-langs.el
+++ b/lisp/progmodes/cc-langs.el
@@ -523,7 +523,7 @@ operator at the top level."
 
 (c-lang-defconst c-symbol-chars
   "Set of characters that can be part of a symbol.
-This is on the form that fits inside [ ] in a regexp."
+This is of the form that fits inside [ ] in a regexp."
   ;; Pike note: With the backquote identifiers this would include most
   ;; operator chars too, but they are handled with other means instead.
   t    (concat c-alnum "_$")