(jit-lock-function): Extend the fontified range

to the beginning of the line containing the range start and
the beginning of the line following the range end.

1 files changed, 12 insertions, 9 deletions

diff --git a/lisp/jit-lock.el b/lisp/jit-lock.el
index d2e94fd69e4..345e46e5295 100644
--- a/lisp/jit-lock.el
+++ b/lisp/jit-lock.el
@@ -246,7 +246,7 @@ is active."
            (parse-sexp-lookup-properties font-lock-syntactic-keywords)
            (old-syntax-table (syntax-table))
            (font-lock-beginning-of-syntax-function nil)
-           next)
+           next font-lock-start font-lock-end)
        (when font-lock-syntax-table
          (set-syntax-table font-lock-syntax-table))
        (save-excursion
@@ -261,17 +261,20 @@ is active."
                    ;; Determine the end of this chunk.
                    (setq next (or (text-property-any start end 'fontified t)
                                   end))
-                   
-                   ;; Goto to the start of the chunk.  Make sure we
-                   ;; start fontifying at the beginning of the line
-                   ;; containing the chunk start because font-lock
-                   ;; functions seem to expects this, if I believe
-                   ;; lazy-lock.
+
+                   ;; Decide which range of text should be fontified.
+                   ;; The problem is that START and NEXT may be in the
+                   ;; middle of something matched by a font-lock regexp.
+                   ;; Until someone has a better idea, let's start
+                   ;; at the start of the line containing START and
+                   ;; stop at the start of the line following NEXT.
+                   (goto-char next)
+                   (setq font-lock-end (line-beginning-position 2))
                    (goto-char start)
-                   (setq start (line-beginning-position))
+                   (setq font-lock-start (line-beginning-position))
                    
                    ;; Fontify the chunk, and mark it as fontified.
-                   (font-lock-fontify-region start end nil)
+                   (font-lock-fontify-region font-lock-start font-lock-end nil)
                    (add-text-properties start next '(fontified t))
                    
                    ;; Find the start of the next chunk, if any.