[nongnu] elpa/idle-highlight-mode e8f724fec2 35/59: Use a local list of overlays for highlighting

[ELPA Syncer]

branch: elpa/idle-highlight-mode
commit e8f724fec25e04282ab2cb62086b29ab59f24ca4
Author: Campbell Barton <ideasman42@gmail.com>
Commit: Campbell Barton <ideasman42@gmail.com>

    Use a local list of overlays for highlighting
    
    Add idle-highlight-exclude-point option to exclude
    the current word from highlighting.
---
 idle-highlight-mode.el | 64 +++++++++++++++++++++++++++++++++++++++++++++-----
 readme.rst             |  2 ++
 2 files changed, 60 insertions(+), 6 deletions(-)

diff --git a/idle-highlight-mode.el b/idle-highlight-mode.el
index d736ece4dc..e1fa6c86ff 100755
--- a/idle-highlight-mode.el
+++ b/idle-highlight-mode.el
@@ -78,6 +78,11 @@
   :group 'idle-highlight
   :type '(repeat symbol))
 
+(defcustom idle-highlight-exclude-point nil
+  "Exclude the current symbol from highlighting."
+  :group 'idle-highlight
+  :type 'boolean)
+
 (defcustom idle-highlight-idle-time 0.5
   "Time after which to highlight the word at point."
   :group 'idle-highlight
@@ -88,6 +93,9 @@
   :type '(repeat symbol)
   :group 'idle-highlight)
 
+(defvar idle-highlight-use-hi-lock-mode nil
+  "Use `hi-lock-mode' option, otherwise use a local list of overlays.")
+
 (defvar-local global-idle-highlight-ignore-buffer nil
   "When non-nil, the global mode will not be enabled for this buffer.
 This variable can also be a predicate function, in which case
@@ -99,6 +107,7 @@ check this buffer.")
 ;; Internal Variables
 
 (defvar-local idle-highlight--regexp nil "Buffer-local regexp to be 
idle-highlighted.")
+(defvar-local idle-highlight--overlays nil "Buffer-local list of overlays.")
 
 ;; ---------------------------------------------------------------------------
 ;; Internal Functions
@@ -139,9 +148,52 @@ Argument POS return faces at this point."
 
 (defun idle-highlight--unhighlight ()
   "Clear current highlight."
-  (when idle-highlight--regexp
-    (unhighlight-regexp idle-highlight--regexp)
-    (setq idle-highlight--regexp nil)))
+  (cond
+    (idle-highlight-use-hi-lock-mode
+      (when idle-highlight--regexp
+        (unhighlight-regexp idle-highlight--regexp)
+        (setq idle-highlight--regexp nil)))
+    (t
+      (when idle-highlight--overlays
+        (mapc 'delete-overlay idle-highlight--overlays)
+        (setq idle-highlight--overlays nil)))))
+
+(defsubst idle-highlight--highlight (target beg end)
+  "Highlight TARGET found between BEG and END.h."
+  (idle-highlight--unhighlight)
+  (setq idle-highlight--regexp (concat "\\<" (regexp-quote target) "\\>"))
+  (cond
+    (idle-highlight-use-hi-lock-mode
+      (highlight-regexp idle-highlight--regexp 'idle-highlight))
+    (t
+      (save-excursion
+        (let
+          (
+            (range-list nil)
+            (beg-ex
+              (progn
+                (goto-char (max (point-min) (min beg (window-start))))
+                (beginning-of-line)
+                (point)))
+            (end-ex
+              (progn
+                (goto-char (min (point-max) (max end (window-end))))
+                (beginning-of-line)
+                (end-of-line)
+                (point))))
+
+          (cond
+            (idle-highlight-exclude-point
+              (setq range-list (list (cons beg-ex beg) (cons end end-ex))))
+            (t
+              (setq range-list (cons beg-ex end-ex))))
+
+          (dolist (range range-list)
+            (goto-char (car range))
+            (while (re-search-forward idle-highlight--regexp (cdr range) t)
+              (let ((ov (make-overlay (match-beginning 0) (match-end 0))))
+                (overlay-put ov 'face 'idle-highlight)
+                (push ov idle-highlight--overlays)))))))))
 
 (defun idle-highlight--word-at-point ()
   "Highlight the word under the point."
@@ -155,8 +207,7 @@ Argument POS return faces at this point."
       (pcase-let* ((`(,beg . ,end) target-range))
         (let ((target (buffer-substring-no-properties beg end)))
           (when (not (member target idle-highlight-exceptions))
-            (setq idle-highlight--regexp (concat "\\<" (regexp-quote target) 
"\\>"))
-            (highlight-regexp idle-highlight--regexp 'idle-highlight)))))))
+            (idle-highlight--highlight target beg end)))))))
 
 
 ;; ---------------------------------------------------------------------------
@@ -275,7 +326,8 @@ Argument POS return faces at this point."
   "Disable the buffer local minor mode."
   (idle-highlight--time-buffer-local-disable)
   (idle-highlight--unhighlight)
-  (kill-local-variable 'idle-highlight--regexp))
+  (kill-local-variable 'idle-highlight--regexp)
+  (kill-local-variable 'idle-highlight--overlays))
 
 (defun idle-highlight--turn-on ()
   "Enable command `idle-highlight-mode'."
diff --git a/readme.rst b/readme.rst
index 96a3bcae5c..68208b232b 100644
--- a/readme.rst
+++ b/readme.rst
@@ -28,6 +28,8 @@ Global Settings
    Words to exclude from highlighting.
 ``idle-highlight-exceptions-face`` '(font-lock-keyword-face 
font-lock-string-face)
    Faces to exclude from highlighting (defaults to ignore keywords & strings).
+``idle-highlight-exclude-point`` nil
+   When non-nil, don't highlight the symbol under the cursor.
 ``idle-highlight-idle-time``
    Delay before highlighting (in seconds).
 ``global-idle-highlight-ignore-modes`` nil