[elpa] externals/indent-bars 9de7111faf 125/431: Initial tab support

[ELPA Syncer]

branch: externals/indent-bars
commit 9de7111fafd93545aa52865863be6dc0cef3c51f
Author: JD Smith <93749+jdtsmith@users.noreply.github.com>
Commit: JD Smith <93749+jdtsmith@users.noreply.github.com>

    Initial tab support
---
 indent-bars.el | 142 ++++++++++++++++++++++++++++++++++++++++++---------------
 1 file changed, 104 insertions(+), 38 deletions(-)

diff --git a/indent-bars.el b/indent-bars.el
index 907d5c3940..330e5548bd 100644
--- a/indent-bars.el
+++ b/indent-bars.el
@@ -336,6 +336,11 @@ color to use for color blending in that case."
   :type 'color
   :group 'indent-bars)
 
+(defcustom indent-bars-skip-leftmost-column t
+  "Whether to skip displaying a bar at the leftmost column."
+  :type 'boolean
+  :group 'indent-bars)
+
 (defcustom indent-bars-spacing-override nil
   "Override for default, major-mode based indentation spacing.
 Set only if the default guessed spacing is incorrect.  Becomes
@@ -708,20 +713,70 @@ variables, which see)."
                             append (cl-loop repeat n collect row)))))
       (list w (length dlist) (string-join dlist)))))
 
-(defun indent-bars--draw (start end &optional bar-from obj no-stipple)
+(defsubst indent-bars--maybe-finalize-tab (cur-tab start obj initial)
+  "Finalize current tab by inserting as display property.
+CUR-TAB, START, OBJ, and INITIAL as in in draw.  Return t if a
+tab was finalized."
+  (when (>= cur-tab 0)
+    (put-text-property (+ start cur-tab) (+ start cur-tab 1)
+                      'display obj initial)
+    t))
+
+(defun indent-bars--draw (start end &optional bar-from obj no-stipple 
initial-tabs)
   "Set bar face in the appropriate locations from START to END.
 Starts at bar number BAR-FROM, one by default.  If passed,
 properties are set from START to END in OBJ, otherwise in the
 buffer.  If NO-STIPPLE is non-nil, rather than setting the bar
-face, instead apply a display character string.  OBJ is
-returned."
+face, instead apply a display character string.  INITIAL-TABS, if
+provided, is the number of tab characters at the start of the
+line or string.  If needed, these will be replaced with
+space-based display strings with the correct bars properties.  If
+INITIAL-TABS is passed, start must be the line or string
+beginning position.  OBJ is returned."
   (let ((prop (if no-stipple 'display 'face))
        (fun (if no-stipple #'indent-bars--no-stipple-char 
#'indent-bars--face)))
-      (cl-loop for pos = start then (+ pos indent-bars-spacing) while (< pos 
end)
-              for barnum from (or bar-from 1)
-              do (put-text-property pos (1+ pos) prop (funcall fun barnum) 
obj)))
+    (if initial-tabs
+       (cl-loop
+        with tab-spaces = (* initial-tabs tab-width)
+        with end = (+ end (- tab-spaces initial-tabs)) ; expand tabs
+        with initial-obj = obj
+        with cur-tab = -1
+        with true-start = (if (and (not obj)
+                                   indent-bars-skip-leftmost-column)
+                              (+ start indent-bars-spacing)
+                            start)
+        for pos = true-start then (+ pos indent-bars-spacing) while (< pos end)
+        for ind = (- pos start)
+        for barnum from (or bar-from 1) do
+        (if (< ind tab-spaces)         ; still within the tabs
+            (let ((tab-num (/ ind tab-width)))
+              (when (> tab-num cur-tab) ; New tab
+                (indent-bars--maybe-finalize-tab cur-tab start obj initial-obj)
+                (setq obj (make-string tab-width ?\s)
+                      cur-tab tab-num)))
+          ;; beyond the tabs
+          (if (indent-bars--maybe-finalize-tab cur-tab start obj initial-obj)
+              (setq obj initial-obj cur-tab -1)))
+        (if (>= cur-tab 0) (setq pos (mod ind tab-width)))
+        (put-text-property pos (1+ pos) prop (funcall fun barnum) obj)
+        finally (indent-bars--maybe-finalize-tab cur-tab start obj 
initial-obj))
+      ;; Normal space-only indent
+      (if (and (not obj) indent-bars-skip-leftmost-column)
+         (setq start (+ start indent-bars-spacing)))
+      (cl-loop
+       for pos = start then (+ pos indent-bars-spacing) while (< pos end)
+       for barnum from (or bar-from 1) do
+       (put-text-property pos (1+ pos) prop (funcall fun barnum) obj))))
   obj)
 
+(defsubst indent-bars--initial-tabs (g)
+  "The number of initial tabs in the most recent match's substring G.
+Returns nil if `indent-tabs-mode' is not set.  BEG and END are
+the match corresponding match string G."
+  (when (and indent-tabs-mode
+            (string-match "^\t+" (match-string g)))
+    (- (match-end 0) (match-beginning 0))))
+
 (defun indent-bars--display ()
   "Display indentation bars based on line contents."
   (save-excursion
@@ -731,7 +786,8 @@ returned."
       (if (> d 0)
          (indent-bars--draw (+ b indent-bars-spacing)
                             (+ b (* d indent-bars-spacing)) nil nil
-                            (or (not (display-graphic-p)) 
indent-bars-prefer-character)))))
+                            (or (not (display-graphic-p)) 
indent-bars-prefer-character)
+                            (indent-bars--initial-tabs 1)))))
   nil)
 
 ;;;; Tree-sitter
@@ -808,9 +864,8 @@ number of bars to add, and BAR-FROM is the starting index 
of the
 first bar (>=1)"
   (concat (make-string off ?\s)
          (cl-loop with sps = (make-string (1- indent-bars-spacing) ?\s)
-                  concat (indent-bars--no-stipple-char depth)
                   for depth from bar-from to (+ bar-from nbars -2)
-                  concat sps)
+                  concat (indent-bars--no-stipple-char depth) sps)
          "\n"))
 
 
@@ -819,23 +874,6 @@ first bar (>=1)"
 (defvar indent-bars--font-lock-blank-line-keywords nil)
 
 (defvar font-lock-beg) (defvar font-lock-end) ; Dynamic font-lock variables!
-(defun indent-bars--extend-blank-line-regions ()
-  "Extend the region about to be font-locked to include stretches of blank 
lines."
-  ;; (message "request to extend: %d->%d" font-lock-beg font-lock-end)
-  (let ((changed nil) (chars " \n"))
-    (goto-char font-lock-beg)
-    (when (< (skip-chars-backward chars) 0)
-      (unless (bolp) (beginning-of-line 2)) ; spaces at end don't count
-      (when (< (point) font-lock-beg)
-       (setq changed t font-lock-beg (point))))
-    (goto-char font-lock-end)
-    (when (> (skip-chars-forward chars) 0)
-      (unless (bolp) (beginning-of-line 1))
-      (when (> (point) font-lock-end)
-       (setq changed t font-lock-end (point))))
-    ;; (if changed (message "expanded to %d->%d" font-lock-beg font-lock-end))
-    changed))
-
 (defun indent-bars--handle-blank-lines ()
   "Display the appropriate bars on regions of one or more blank-only lines.
 Only called by font-lock if `indent-bars-display-on-blank-lines'
@@ -874,13 +912,20 @@ of those types (e.g. module)."
            (let* ((bp (line-beginning-position))
                   (ep (line-end-position))
                   (len (- ep bp))
-                  (nbars (/ (max 0 (1- len)) indent-bars-spacing)))
-             ;; Draw "real" bars in existing blank text
-             (if (> nbars 0) (indent-bars--draw (+ bp indent-bars-spacing)
-                                                ep nil nil no-stipple))
-             ;; Add fake bars, via display
-             (when (> ctxbars nbars)
-               (let* ((off (- (* (1+ nbars) indent-bars-spacing) len))
+                  (nbars (cond ; including (possible) bar at bol!
+                          ((> len indent-bars-spacing)
+                           (1+ (/ (1- len) indent-bars-spacing)))
+                          ((> len 0) 1)
+                          (t 0))))
+             ;; Draw "real" bars on existing blanks
+             (if (> nbars 0)
+                 (indent-bars--draw bp ep nil nil no-stipple
+                                    (indent-bars--initial-tabs  0)))
+             ;; Add fake bars via display property on the line's terminating 
newline
+             (when (>= ctxbars nbars)
+               (let* ((off (- (* nbars indent-bars-spacing) len))
+                      (off (if (and indent-bars-skip-leftmost-column (= nbars 
0))
+                               (+ off indent-bars-spacing) off))
                       (s (if no-stipple
                              (indent-bars--no-stipple-blank-string
                               off (- ctxbars nbars) (1+ nbars))
@@ -891,6 +936,23 @@ of those types (e.g. module)."
              (beginning-of-line 2)))))
       nil)))
 
+(defun indent-bars--extend-blank-line-regions ()
+  "Extend the region about to be font-locked to include stretches of blank 
lines."
+  ;; (message "request to extend: %d->%d" font-lock-beg font-lock-end)
+  (let ((changed nil) (chars " \t\n"))
+    (goto-char font-lock-beg)
+    (when (< (skip-chars-backward chars) 0)
+      (unless (bolp) (beginning-of-line 2)) ; spaces at end don't count
+      (when (< (point) font-lock-beg)
+       (setq changed t font-lock-beg (point))))
+    (goto-char font-lock-end)
+    (when (> (skip-chars-forward chars) 0)
+      (unless (bolp) (beginning-of-line 1))
+      (when (> (point) font-lock-end)
+       (setq changed t font-lock-end (point))))
+    ;; (if changed (message "expanded to %d->%d" font-lock-beg font-lock-end))
+    changed))
+
 ;;;; Current indentation highlight
 (defvar-local indent-bars--current-depth 0)
 (defvar indent-bars--current-bg-color nil)
@@ -1007,6 +1069,8 @@ Adapted from `highlight-indentation-mode'."
     yaml-indent-offset)
    ((and (derived-mode-p 'elixir-mode) (boundp 'elixir-smie-indent-basic))
     elixir-smie-indent-basic)
+   ((and (derived-mode-p 'lisp-data-mode) (boundp 'lisp-body-indent))
+    lisp-body-indent)
    ((and (boundp 'standard-indent) standard-indent))
    (t 4)))                             ; backup
 
@@ -1016,7 +1080,13 @@ Adapted from `highlight-indentation-mode'."
     (setq indent-bars-orig-unfontify-region 
font-lock-unfontify-region-function))
   (setq-local font-lock-unfontify-region-function #'indent-bars--unfontify)
   (setq indent-bars--font-lock-keywords
-       `((,(rx-to-string `(seq bol (group (>= ,(1+ indent-bars-spacing) ?\s)) 
nonl))
+       `((,(rx-to-string `(seq bol
+                               (group
+                                ,(if (and (not indent-tabs-mode)
+                                          indent-bars-skip-leftmost-column)
+                                     `(>= ,(1+ indent-bars-spacing) ?\s)
+                                   '(+ (any ?\t ?\s))))
+                               nonl))
           (1 (indent-bars--display)))))
   (font-lock-add-keywords nil indent-bars--font-lock-keywords t)
   (if indent-bars-display-on-blank-lines
@@ -1030,10 +1100,6 @@ Adapted from `highlight-indentation-mode'."
 (defvar indent-bars-mode)
 (defun indent-bars-setup ()
   "Setup all face, color, bar size, and indentation info for the current 
buffer."
-  (when indent-tabs-mode
-    (setq indent-bars-mode nil)
-    (error "Indent-bars does not support indent-tabs-mode=t; disabling"))
-  
   ;; Spacing
   (setq indent-bars-spacing (indent-bars--guess-spacing))