[nongnu] elpa/go-mode 8ddf0b3 433/495: Speed up go-goto-opening-parenthesis

[ELPA Syncer]

branch: elpa/go-mode
commit 8ddf0b369cff246d7e14f4592c8c053bda36b2eb
Author: Muir Manders <muir@retailnext.net>
Commit: Peter Sanford <psanford@sanford.io>

    Speed up go-goto-opening-parenthesis
    
    Reimplement to use syntax tables directly rather than
    backward-up-list. It is much faster now, and it seems to work the same
    for our use case. Certain files are affected more than others. For
    example, reindenting golang/src/cmd/internal/obj/x86/avx_optabs.go
    went from 19.6s to 5.7s after this change.
    
    I think it is faster because syntax-ppss caches the syntax info,
    where backward-up-list calls up-list which calls scan-lists which does
    a lot of work every time.
    
    Closes: #283 [via git-merge-pr]
---
 go-mode.el | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/go-mode.el b/go-mode.el
index 6ccddde..b5575d2 100644
--- a/go-mode.el
+++ b/go-mode.el
@@ -66,11 +66,9 @@ Return non-nil if there was a paren to move up to."
   ;; function's outcome.
 
   ;; Silently fail if there's no matching opening parenthesis.
-  (condition-case nil
-      (progn
-        (backward-up-list)
-        t)
-    (scan-error nil)))
+  (let ((open-char (nth 1 (syntax-ppss))))
+    (when open-char
+      (goto-char open-char))))
 
 
 (defconst go-dangling-operators-regexp "[^-]-\\|[^+]\\+\\|[/*&><.=|^]")