From 0e09d00f29e370ecfe2f2b22acff7b98c448bc30 Mon Sep 17 00:00:00 2001
From: Alan Mackenzie <acm@muc.de>
Date: Fri, 12 May 2017 21:11:49 +0000
Subject: [PATCH] Fontify C++ for loop variable as variable, even when followed
 by parentheses

In the following: "for (auto *Friend : Class->friends()) {", "Friend" was
getting fontified as a function, due to insufficient checking of the tokens
between it and "()".

* lisp/progmodes/cc-langs.el (c-:-op-cont-tokens, c-:-op-cont-regexp): New
lang-consts/vars.

* lisp/progmodes/cc-engine.el (c-forward-declarator): After finding a putative
declarator's identifier, check for a ":" token inside a for's parentheses, and
abort the search for "(" if this is found.
---
 lisp/progmodes/cc-engine.el | 25 +++++++++++++++++++++++--
 lisp/progmodes/cc-langs.el  | 15 +++++++++++++++
 2 files changed, 38 insertions(+), 2 deletions(-)

diff --git a/lisp/progmodes/cc-engine.el b/lisp/progmodes/cc-engine.el
index 6d7bab7a65c..9773b1ca85b 100644
--- a/lisp/progmodes/cc-engine.el
+++ b/lisp/progmodes/cc-engine.el
@@ -8092,8 +8092,29 @@ comment at the start of cc-engine.el for more info."
 	 ;; initializing brace lists.
 	 (let (found)
 	   (while
-	       (and (setq found (c-syntactic-re-search-forward
-				 "[;,]\\|\\s)\\|\\'\\|\\(=\\|\\s(\\)" limit t t))
+	       (and (progn
+		      ;; In the next loop, we keep searching forward whilst
+		      ;; we find ":"s which aren't single colons inside C++
+		      ;; "for" statements.
+		      (while
+			  (and
+			   (setq found
+				 (c-syntactic-re-search-forward
+				  "[;:,]\\|\\s)\\|\\'\\|\\(=\\|\\s(\\)"
+				  limit t t))
+			   (eq (char-before) ?:)
+			   (if (looking-at c-:-op-cont-regexp)
+			       (progn (goto-char (match-end 0)) t)
+			     (not
+			      (and (c-major-mode-is 'c++-mode)
+				   (save-excursion
+				     (and
+				      (c-go-up-list-backward)
+				      (eq (char-after) ?\()
+				      (progn (c-backward-syntactic-ws)
+					     (c-simple-skip-symbol-backward))
+				      (looking-at c-paren-stmt-key))))))))
+		      found)
 		    (eq (char-before) ?\[)
 		    (c-go-up-list-forward))
 	     (setq brackets-after-id t))
diff --git a/lisp/progmodes/cc-langs.el b/lisp/progmodes/cc-langs.el
index 3b455fc0908..84d4eab75af 100644
--- a/lisp/progmodes/cc-langs.el
+++ b/lisp/progmodes/cc-langs.el
@@ -1334,6 +1334,21 @@ operators."
 (c-lang-defvar c-multichar->-op-not->>-regexp
   (c-lang-const c-multichar->-op-not->>-regexp))
 
+(c-lang-defconst c-:-op-cont-tokens
+  ;; A list of second and subsequent characters of all multicharacter tokens
+  ;; that begin with ":".
+  t (c-filter-ops (c-lang-const c-all-op-syntax-tokens)
+		  t
+		  "\\`:."
+		  (lambda (op) (substring op 1))))
+
+(c-lang-defconst c-:-op-cont-regexp
+  ;; Regexp matching the second and subsequent characters of all
+  ;; multicharacter tokens that begin with ":".
+  t (c-make-keywords-re nil (c-lang-const c-:-op-cont-tokens)))
+(c-lang-defvar c-:-op-cont-regexp
+  (c-lang-const c-:-op-cont-regexp))
+
 (c-lang-defconst c-stmt-delim-chars
   ;; The characters that should be considered to bound statements.  To
   ;; optimize `c-crosses-statement-barrier-p' somewhat, it's assumed to
-- 
2.39.2