[nongnu] elpa/go-mode d17d210 489/495: Improve go-fontify-variables logic.

[ELPA Syncer]

branch: elpa/go-mode
commit d17d21060b16a77f9ee28ff453e674225acbf1b1
Author: Muir Manders <muir@mnd.rs>
Commit: Peter Sanford <psanford@sanford.io>

    Improve go-fontify-variables logic.
    
    Previously when go-fontify-variables was nil we would avoid fontifying
    variables by swapping in the "default" face instead of
    "font-lock-variable-name-face". This worked, but recently I've noticed
    it had unintended side effects. Namely it doesn't play well when other
    modes (such as vc diff) add overlay faces. The "default" font lock
    face overrides the overlay background, so your Go variables look bad
    in vc diff buffers.
    
    Fix by instead zeroing out the relevant match data so nothing gets
    font locked at all.
    
    Closes: #368 [via git-merge-pr]
---
 go-mode.el | 17 ++++++++++-------
 1 file changed, 10 insertions(+), 7 deletions(-)

diff --git a/go-mode.el b/go-mode.el
index 6340fa2..1675280 100644
--- a/go-mode.el
+++ b/go-mode.el
@@ -411,9 +411,6 @@ For mode=set, all covered lines will have this weight."
     st)
   "Syntax table for Go mode.")
 
-(defvar go--default-face 'default
-  "A variable to refer to `default' face for use in font lock rules.")
-
 (defun go--fontify-type-switch-case-pre ()
   "Move point to line following the end of case statement.
 
@@ -445,7 +442,7 @@ statements."
        ;; Post-match form that runs after last sub-match.
        (go--fontify-param-post)
        ;; Subexp 1 is the param variable name, if any.
-       (1 ,(if go-fontify-variables 'font-lock-variable-name-face 
'go--default-face))
+       (1 font-lock-variable-name-face nil t)
        ;; Subexp 2 is the param type name, if any. We set the LAXMATCH
        ;; flag to allow optional regex groups.
        (2 font-lock-type-face nil t)))
@@ -467,7 +464,7 @@ statements."
      ;; Match variable names in var decls, constant names in const
      ;; decls, and type names in type decls.
      (go--match-decl
-      (1 ,(if go-fontify-variables 'font-lock-variable-name-face 
'go--default-face) nil t)
+      (1 font-lock-variable-name-face nil t)
       (2 font-lock-constant-face nil t)
       (3 font-lock-type-face nil t))
 
@@ -1439,6 +1436,10 @@ the next comma or to the closing paren."
     (while (and (not found-match) (not done))
       (if go--fontify-param-has-name
           (when (looking-at go--named-param-re)
+            (when (not go-fontify-variables)
+              (let ((md (match-data)))
+                (setf (nth 2 md) nil (nth 3 md) nil)
+                (set-match-data md)))
             (setq found-match t))
         (when (looking-at go--unnamed-param-re)
           (setq found-match t)))
@@ -1546,14 +1547,16 @@ gets highlighted by the font lock keyword."
           (let ((md (match-data)))
             (cond
              ((string= decl "var")
-              (setf (nth 4 md) nil (nth 5 md) nil (nth 6 md) nil (nth 7 md) 
nil))
+              (setf (nth 4 md) nil (nth 5 md) nil (nth 6 md) nil (nth 7 md) 
nil)
+              (when (not go-fontify-variables)
+                (setf (nth 2 md) nil (nth 3 md) nil)))
              ((string= decl "const")
               (setf (nth 2 md) nil (nth 3 md) nil (nth 6 md) nil (nth 7 md) 
nil))
              ((string= decl "type")
               (setf (nth 2 md) nil (nth 3 md) nil (nth 4 md) nil (nth 5 md) 
nil)))
             (set-match-data md)))
 
-         (t
+         (go-fontify-variables
           (save-match-data
             ;; Left side of ":=" assignmnet.
             (when (looking-at ".*:=")