Merge from origin/emacs-26

1e5949642a ; * src/gtkutil.c (xg_create_frame_widgets): Add FIXME re....
e7c8da4d05 bug#28609: simple.el
827db6b559 Use a separate syntax-ppss cache for narrowed buffers
a2244f417a Improve python3-compatibility of fallback completion (Bug#...
79162cb0db Fix subr-x-tests when running from elc
66d35ae49d * lisp/eshell/esh-util.el (eshell-condition-case): Add deb...
f5e72b04d9 Make sh-indentation into an alias for sh-basic-offset (Bug...
a58d0c590a Fix loading of smie-config rules (Bug#24848)
3a68dec327 ; Update NEWS for the change in eldoc-message
5a41dd0a1f Reset default-directory inside *xref-grep* buffer
49cd561dc6 * test/lisp/tramp-tests.el (tramp-test21-file-links): Spec...
b719f6b20b Loosen strict parsing requirement for desktop files
c7a0c13777 * lisp/xdg.el (xdg-thumb-uri): Fix doc string.
dc6b3560e5 Fix documentation of `make-frame' and related variables an...
3d3778d82a Accept new `always' value for option `buffer-offer-save'
638f64c40a Improve new NS scrolling variable names
d93301242f Document 'replace-buffer-contents' in the manual.
00e4e3e9d2 Fix undecorated frame resizing issues on NS (bug#28512)
820739bbb5 ; * doc/emacs/display.texi (Display Custom): Fix wording.
f2b2201594 ; Spelling and URL fixes
0e143b1fc5 Documentation improvements for 'display-line-numbers'
f656ccdb43 ; Fix typo
d64da52d57 Fix last change in bat-mode.el
908af46abd Fix restoring in GUI sessions desktop saved in TTY sessions
51cbd85454 Improve syntax highlighting in bat-mode
0273916618 Document the 'list-FOO' convention
d24ec58540 Expose viewing conditions in CAM02-UCS metric
a81d5a3d3f Revert "Set frame size to actual requested size (bug#18215)"
0bf066d4b2 Add tests for Edebug
68baca3ee1 Catch more messages in ert-with-message-capture
28e0c410c9 ; * lisp/mouse.el (secondary-selection-exist-p): Doc fix.
31e1d9ef2f Support setting region from secondary selection and vice v...
047f02f00f Fix new copy-directory bug with empty dirs
fbd15836af * doc/lispref/strings.texi (Formatting Strings): Improve i...
f16a8d5dbd Fix 2 testsuite tests for MS-Windows
965cffd89c Rename timer-list to list-timers
a5fec62b51 Provide native touchpad scrolling on macOS
7b3d1c6beb Fix MinGW64 build broken by recent MinGW64 import libraries
c83d0c5fdf Fix crashes in 'move-point-visually' in minibuffer windows
7f3d5f929d * src/emacs.c (usage_message): Don't mention 'find-file'.
6845282200 Fix a minor inaccuracy in the Emacs manual
74d7bb9498 Fix errors in flyspell-post-command-hook
40fdbb01d0 Work on Tramp's file-truename
1a01423b3c Fix bug with make-directory on MS-Windows root
066efb8666 Fix log-view-diff-common when point is after last entry
3f006b56cd Adapt fileio-tests--symlink-failure to Cygwin
ee512e9a82 Ignore buffers whose name begins with a space in save-some...
9e1b5bd92c Improve tramp-interrupt-process robustness
8d4223e61b Minor Tramp doc update
331d0e520f Fix gensym
466df76f7d Cleanup in files-tests.el
6359fe630a Remove old cl-assert calls in 'newline'
059184e645 Avoid crash with C-g C-g in GC
541006c536 Fix format-time-string %Z bug with negative tz
679e05eeb9 message-citation-line-format %Z is now tz name
4e8888d438 Use doc-view or pdf-tools on any window-system
5f28f0db73 Fix bug with min and max and NaNs
37b5e661d2 Fix recently-introduced copy-directory bug
6bbbc38b34 Merge from Gnulib
57249fb297 Fix compatibility problem in Tramp
411bec82c4 Avoid GCC 7 compilation warning in eval.c
34a6774daa ; Partially revert c3445aed5194
3003ac0469 Adapt Tramp version.  Do not merge
48d39c39e8 Search for Syntax section when viewing MDN
9d101376b4 Allow smerge-keep-current to work for empty hunks
13aba24add Call vc-setup-buffer in vc-git-log-{in,out}going
1d599df5e0 Fix last change to textmodes/page-ext.el
a726e09a9a * test/src/lcms-tests.el (lcms-cri-cam02-ucs): Skip if lcm...
546413e1ac * test/src/lcms-tests.el (lcms-whitepoint): Skip if lcms2 ...
96aaeaaffa ; * src/lcms.c: Minor stylistic changes in comments.
c3df816585 Fix compilation warning in etags.c

2 files changed, 74 insertions, 37 deletions

diff --git a/lisp/emacs-lisp/smie.el b/lisp/emacs-lisp/smie.el
index 87c4782e217..da1e12b1408 100644
--- a/lisp/emacs-lisp/smie.el
+++ b/lisp/emacs-lisp/smie.el
@@ -1956,7 +1956,7 @@ E.g. provided via a file-local call to `smie-config-local'.")
 (defvar smie-config--modefuns nil)
 
 (defun smie-config--setter (var value)
-  (setq-default var value)
+  (set-default var value)
   (let ((old-modefuns smie-config--modefuns))
     (setq smie-config--modefuns nil)
     (pcase-dolist (`(,mode . ,rules) value)
@@ -1982,7 +1982,7 @@ value with which to replace it."
   ;; FIXME improve value-type.
   :type '(choice (const nil)
                  (alist :key-type symbol))
-  :initialize 'custom-initialize-default
+  :initialize 'custom-initialize-set
   :set #'smie-config--setter)
 
 (defun smie-config-local (rules)
diff --git a/lisp/emacs-lisp/syntax.el b/lisp/emacs-lisp/syntax.el
index f6137837858..9eb6bde7454 100644
--- a/lisp/emacs-lisp/syntax.el
+++ b/lisp/emacs-lisp/syntax.el
@@ -381,10 +381,26 @@ This function should move the cursor back to some syntactically safe
 point (where the PPSS is equivalent to nil).")
 (make-obsolete-variable 'syntax-begin-function nil "25.1")
 
-(defvar-local syntax-ppss-cache nil
-  "List of (POS . PPSS) pairs, in decreasing POS order.")
-(defvar-local syntax-ppss-last nil
-  "Cache of (LAST-POS . LAST-PPSS).")
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+;; Several caches.
+;;
+;; Because `syntax-ppss' is equivalent to (parse-partial-sexp
+;; (POINT-MIN) x), we need either to empty the cache when we narrow
+;; the buffer, which is suboptimal, or we need to use several caches.
+;; We use two of them, one for widened buffer, and one for narrowing.
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+
+(defvar-local syntax-ppss-wide nil
+  "Cons of two elements (LAST . CACHE).
+Where LAST is a pair (LAST-POS . LAST-PPS) caching the last invocation
+and CACHE is a list of (POS . PPSS) pairs, in decreasing POS order.
+These are valid when the buffer has no restriction.")
+
+(defvar-local syntax-ppss-narrow nil
+  "Same as `syntax-ppss-wide' but for a narrowed buffer.")
+
+(defvar-local syntax-ppss-narrow-start nil
+  "Start position of the narrowing for `syntax-ppss-narrow'.")
 
 (defalias 'syntax-ppss-after-change-function 'syntax-ppss-flush-cache)
 (defun syntax-ppss-flush-cache (beg &rest ignored)
@@ -392,24 +408,29 @@ point (where the PPSS is equivalent to nil).")
   ;; Set syntax-propertize to refontify anything past beg.
   (setq syntax-propertize--done (min beg syntax-propertize--done))
   ;; Flush invalid cache entries.
-  (while (and syntax-ppss-cache (> (caar syntax-ppss-cache) beg))
-    (setq syntax-ppss-cache (cdr syntax-ppss-cache)))
-  ;; Throw away `last' value if made invalid.
-  (when (< beg (or (car syntax-ppss-last) 0))
-    ;; If syntax-begin-function jumped to BEG, then the old state at BEG can
-    ;; depend on the text after BEG (which is presumably changed).  So if
-    ;; BEG=(car (nth 10 syntax-ppss-last)) don't reuse that data because the
-    ;; assumed nil state at BEG may not be valid any more.
-    (if (<= beg (or (syntax-ppss-toplevel-pos (cdr syntax-ppss-last))
-                    (nth 3 syntax-ppss-last)
-                    0))
-	(setq syntax-ppss-last nil)
-      (setcar syntax-ppss-last nil)))
-  ;; Unregister if there's no cache left.  Sadly this doesn't work
-  ;; because `before-change-functions' is temporarily bound to nil here.
-  ;; (unless syntax-ppss-cache
-  ;;   (remove-hook 'before-change-functions 'syntax-ppss-flush-cache t))
-  )
+  (dolist (cell (list syntax-ppss-wide syntax-ppss-narrow))
+    (pcase cell
+      (`(,last . ,cache)
+       (while (and cache (> (caar cache) beg))
+         (setq cache (cdr cache)))
+       ;; Throw away `last' value if made invalid.
+       (when (< beg (or (car last) 0))
+         ;; If syntax-begin-function jumped to BEG, then the old state at BEG can
+         ;; depend on the text after BEG (which is presumably changed).  So if
+         ;; BEG=(car (nth 10 syntax-ppss-last)) don't reuse that data because the
+         ;; assumed nil state at BEG may not be valid any more.
+         (if (<= beg (or (syntax-ppss-toplevel-pos (cdr last))
+                         (nth 3 last)
+                         0))
+	     (setq last nil)
+           (setcar last nil)))
+       ;; Unregister if there's no cache left.  Sadly this doesn't work
+       ;; because `before-change-functions' is temporarily bound to nil here.
+       ;; (unless cache
+       ;;   (remove-hook 'before-change-functions 'syntax-ppss-flush-cache t))
+       (setcar cell last)
+       (setcdr cell cache)))
+    ))
 
 (defvar syntax-ppss-stats
   [(0 . 0.0) (0 . 0.0) (0 . 0.0) (0 . 0.0) (0 . 0.0) (1 . 2500.0)])
@@ -423,6 +444,17 @@ point (where the PPSS is equivalent to nil).")
 (defvar-local syntax-ppss-table nil
   "Syntax-table to use during `syntax-ppss', if any.")
 
+(defun syntax-ppss--data ()
+  (if (eq (point-min) 1)
+      (progn
+        (unless syntax-ppss-wide
+          (setq syntax-ppss-wide (cons nil nil)))
+        syntax-ppss-wide)
+    (unless (eq syntax-ppss-narrow-start (point-min))
+      (setq syntax-ppss-narrow-start (point-min))
+      (setq syntax-ppss-narrow (cons nil nil)))
+    syntax-ppss-narrow))
+
 (defun syntax-ppss (&optional pos)
   "Parse-Partial-Sexp State at POS, defaulting to point.
 The returned value is the same as that of `parse-partial-sexp'
@@ -439,10 +471,13 @@ running the hook."
   (syntax-propertize pos)
   ;;
   (with-syntax-table (or syntax-ppss-table (syntax-table))
-  (let ((old-ppss (cdr syntax-ppss-last))
-	(old-pos (car syntax-ppss-last))
-	(ppss nil)
-	(pt-min (point-min)))
+  (let* ((cell (syntax-ppss--data))
+         (ppss-last (car cell))
+         (ppss-cache (cdr cell))
+         (old-ppss (cdr ppss-last))
+         (old-pos (car ppss-last))
+         (ppss nil)
+         (pt-min (point-min)))
     (if (and old-pos (> old-pos pos)) (setq old-pos nil))
     ;; Use the OLD-POS if usable and close.  Don't update the `last' cache.
     (condition-case nil
@@ -475,7 +510,7 @@ running the hook."
 	   ;; The OLD-* data can't be used.  Consult the cache.
 	   (t
 	    (let ((cache-pred nil)
-		  (cache syntax-ppss-cache)
+		  (cache ppss-cache)
 		  (pt-min (point-min))
 		  ;; I differentiate between PT-MIN and PT-BEST because
 		  ;; I feel like it might be important to ensure that the
@@ -491,7 +526,7 @@ running the hook."
 	      (if cache (setq pt-min (caar cache) ppss (cdar cache)))
 
 	      ;; Setup the before-change function if necessary.
-	      (unless (or syntax-ppss-cache syntax-ppss-last)
+	      (unless (or ppss-cache ppss-last)
 		(add-hook 'before-change-functions
 			  'syntax-ppss-flush-cache t t))
 
@@ -541,7 +576,7 @@ running the hook."
 			      pt-min (setq pt-min (/ (+ pt-min pos) 2))
 			      nil nil ppss))
                   (push (cons pt-min ppss)
-                        (if cache-pred (cdr cache-pred) syntax-ppss-cache)))
+                        (if cache-pred (cdr cache-pred) ppss-cache)))
 
 		;; Compute the actual return value.
 		(setq ppss (parse-partial-sexp pt-min pos nil nil ppss))
@@ -562,13 +597,15 @@ running the hook."
 		      (if (> (- (caar cache-pred) pos) syntax-ppss-max-span)
 			  (push pair (cdr cache-pred))
 			(setcar cache-pred pair))
-		    (if (or (null syntax-ppss-cache)
-			    (> (- (caar syntax-ppss-cache) pos)
+		    (if (or (null ppss-cache)
+			    (> (- (caar ppss-cache) pos)
 			       syntax-ppss-max-span))
-			(push pair syntax-ppss-cache)
-		      (setcar syntax-ppss-cache pair)))))))))
+			(push pair ppss-cache)
+		      (setcar ppss-cache pair)))))))))
 
-	  (setq syntax-ppss-last (cons pos ppss))
+	  (setq ppss-last (cons pos ppss))
+          (setcar cell ppss-last)
+          (setcdr cell ppss-cache)
 	  ppss)
       (args-out-of-range
        ;; If the buffer is more narrowed than when we built the cache,
@@ -582,7 +619,7 @@ running the hook."
 (defun syntax-ppss-debug ()
   (let ((pt nil)
 	(min-diffs nil))
-    (dolist (x (append syntax-ppss-cache (list (cons (point-min) nil))))
+    (dolist (x (append (cdr (syntax-ppss--data)) (list (cons (point-min) nil))))
       (when pt (push (- pt (car x)) min-diffs))
       (setq pt (car x)))
     min-diffs))