[elpa] externals/indent-bars ce7fb0641c 189/431: refactoring treesitter to new file: initial stage

[ELPA Syncer]

branch: externals/indent-bars
commit ce7fb0641cf1e5e170cc3d697b1336454276715b
Author: JD Smith <93749+jdtsmith@users.noreply.github.com>
Commit: JD Smith <93749+jdtsmith@users.noreply.github.com>

    refactoring treesitter to new file: initial stage
---
 indent-bars-ts.el | 163 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 indent-bars.el    | 160 +++++++++--------------------------------------------
 2 files changed, 189 insertions(+), 134 deletions(-)

diff --git a/indent-bars-ts.el b/indent-bars-ts.el
new file mode 100644
index 0000000000..cb20c3eff4
--- /dev/null
+++ b/indent-bars-ts.el
@@ -0,0 +1,163 @@
+;;; indent-bars-ts.el --- treesitter support for indent-bars -*- 
lexical-binding: t; -*-
+;; Copyright (C) 2023  J.D. Smith
+
+;;; Commentary:
+
+;; tree-sitter support for indent-bars:
+
+;;  - Optionally uses tree-sitter to fine-tune indentation depth
+;;    (avoiding "too many bars" in e.g. argument lists)
+;;  - Use treesitter to avoid adding bars to blank lines in strings or
+;;    other types.
+;;  - Enable alternate styling for bars inside and outside the
+;;    treesitter "scope", where scope is defined as the wrapping
+;;    elements configured in `indent-bars-ts`.
+
+(require 'seq)
+(require 'treesit nil t) ; treesit is optional
+(require 'indent-bars)
+
+;;;; Customization
+
+
+
+(defcustom indent-bars-treesit-wrap nil
+    "An alist of language and treesitter node type symbols to wrap.
+Inside such wrapping types, indentation bar depth will not be
+increased more than one beyond that of the containing node's
+depth.  This is typically done for lists, parameters, function
+arguments, etc., to avoid unwanted \"extra bars\".  Types must be
+valid node types for the grammar of the language indicated."
+    :type '(choice (const :tag "No wrap types" nil)
+                  (alist :tag "Alist of node types"
+                         :key-type (symbol :tag "Language")
+                         :value-type (repeat :tag "Types" (symbol :tag 
"Type"))))
+    :group 'indent-bars)
+
+(defcustom indent-bars-treesit-shadow-scope nil
+  "An alist of language and treesitter node types to emphasize.
+Bars on text ouside of the matching treesitter nodes will be
+de-emphasized with alternative \"shadow\" style."
+  :type '(choice (const :tag "Scope types" nil)
+                (alist :tag "Alist of node types"
+                       :key-type (symbol :tag "Language")
+                       :value-type (repeat :tag "Types" (symbol :tag "Type"))))
+  :group 'indent-bars)
+
+(defcustom indent-bars-treesit-ignore-blank-lines-types nil
+  "Do not style blank lines when the type of node at start is in this list.
+Either nil, or a list of node type strings to avoid adding blank
+line styling to.  Typically \"top-level\" node types like
+\"module\", \"program\", and \"translation_unit\" would be used
+here, and they need not be valid types for any particular
+grammar.  Only applicable if `indent-bars-display-on-blank-lines'
+is set."
+  :type '(choice (const :tag "None" nil)
+                (repeat :tag "Node types" string))
+  :group 'indent-bars)
+
+(defcustom indent-bars-no-descend-string 'string
+  "Configure bar behavior inside treesitter-matched strings.
+If non-nil, set to a symbol naming a tree-sitter string node type
+into which bars will go no deeper than their starting line.  If
+this node type is invalid, a message is printed and the feature
+is disabled."
+  :local t
+  :type '(choice (const :tag "Disable" nil) (symbol :tag "Node Type"))
+  :group 'indent-bars)
+
+;;;; Tree-sitter
+(defvar-local indent-bars-ts--parser nil)
+(defvar-local indent-bars-ts--query nil)
+(defvar-local indent-bars-ts--string-query nil)
+
+(defun indent-bars-ts--node-query (node query &optional start-only 
first-spanning)
+  "Capture node(s) spanning NODE matching QUERY.
+QUERY is a compiled treesit query.  If START-ONLY is non-nil, the
+query searches for matching nodes spanning the start of the node
+at point, otherwise nodes which intersect anywhere with the node
+will be returned.  If FIRST-SPANNING is non-nil, return the first
+matching node, but only if it fully spans the full start..end
+range of NODE, otherwise return nil."
+  (let* ((start (treesit-node-start node))
+        (end (if start-only start (treesit-node-end node)))
+        (nodes (treesit-query-capture indent-bars-ts--parser query
+                                      start end t)))
+    (when (and first-spanning nodes)
+      (let ((n (car nodes)))
+       (setq nodes
+             (and (<= (treesit-node-start n) start)
+                  (>= (treesit-node-end n) end)
+                  n))))
+    nodes))
+
+(defsubst indent-bars--indent-at-node (node)
+  "Return the current indentation at the start of TS node NODE."
+  (save-excursion
+    (goto-char (treesit-node-start node))
+    (current-indentation)))
+
+(defun indent-bars-ts--update-indentation-depth (d)
+  "Update depth D using tree-sitter-region."
+  (if-let (((not (bobp)))
+          (node (treesit-node-on (1- (point)) (point) indent-bars-ts--parser))
+          (dnew
+           (if (and indent-bars-no-descend-string
+                    (indent-bars-ts--node-query
+                     node indent-bars-ts--string-query t))
+               ;; A string: do not descend
+               (1+ (indent-bars--depth (indent-bars--indent-at-node node)))
+             ;; Check context
+             (when-let ((ctx (indent-bars-ts--node-query
+                              node indent-bars-ts--query nil t)))
+               (1+ (indent-bars--depth
+                    (indent-bars--indent-at-node ctx)))))))
+      (min dnew d)
+    d))
+
+
+(defun indent-bars--ignore-blank (beg)
+  "See if blank lines at BEG should be ignored using tree-sitter.
+Blank lines to ignore are those with types in
+`indent-bars-treesit-ignore-blank-lines-types'."
+  (and indent-bars-ts--parser
+       indent-bars-treesit-ignore-blank-lines-types
+       (when-let ((n (treesit-node-on beg beg)))
+        (seq-contains-p indent-bars-treesit-ignore-blank-lines-types
+                        (treesit-node-type n)))))
+
+
+(defun indent-bars-ts--handle-blank-lines ()
+  "Wrapper for `indent-bars--handle-blank-lines' that works with treesitter.
+
+If `indent-bars-treesit-ignore-blank-lines-types' is configured,
+ignore blank lines whose starting positions are directly spanned
+by nodes of those types (e.g. module)."
+  (unless (indent-bars--ignore-blank (match-beginning 0))
+    (indent-bars--handle-blank-lines)))
+
+;;;###autoload
+(defun indent-bars-ts-setup ()
+  "Setup indent-bars for using with treesiter."
+  (when-let (((fboundp #'treesit-available-p))
+            ((treesit-available-p))
+            (lang (treesit-language-at (point-min)))
+            (types (alist-get lang indent-bars-treesit-wrap)))
+    (setq indent-bars-ts--parser
+         (cl-find lang (treesit-parser-list) :key #'treesit-parser-language)
+         indent-bars-ts--query
+         (treesit-query-compile lang `([,@(mapcar #'list types)] @ctx)))
+    (when indent-bars-no-descend-string
+      (let ((query `([(,indent-bars-no-descend-string)] @s))
+           (pm (point-min)))
+       (setq indent-bars-ts--string-query (treesit-query-compile lang query))
+       ;; Test it to be sure
+       (condition-case err
+           (treesit-query-capture indent-bars-ts--parser
+                                  indent-bars-ts--string-query pm pm t)
+         (treesit-query-error
+          (setq indent-bars-no-descend-string nil)
+          (message "indent-bars: malformed string query; disabling.  See 
indent-bars-no-descend-string.\n%s" err)))))
+    (setq indent-bars--update-depth-function
+         #'indent-bars-ts--update-indentation-depth)
+    ))
diff --git a/indent-bars.el b/indent-bars.el
index 34998dec3a..f16ea493b6 100644
--- a/indent-bars.el
+++ b/indent-bars.el
@@ -43,7 +43,7 @@
 (require 'outline)
 (require 'font-lock)
 (require 'compat)
-(require 'treesit nil t) ; treesit is optional
+
 
 ;;;; Customization
 (defgroup indent-bars nil
@@ -380,47 +380,11 @@ buffer-local automatically."
   :type '(choice integer (const :tag "Discover automatically" :value nil))
   :group 'indent-bars)
 
-;;;;; Treesitter
 (defcustom indent-bars-treesit-support nil
   "Whether to enable tree-sitter support (if available)."
   :type 'boolean
   :group 'indent-bars)
 
-(defcustom indent-bars-treesit-wrap nil
-    "An alist of language and treesitter node type symbols to wrap.
-Inside such wrapping types, indentation bar depth will not be
-increased more than one beyond that of the containing node's
-depth.  This is typically done for lists, parameters, function
-arguments, etc., to avoid unwanted \"extra bars\".  Types must be
-valid node types for the grammar of the language indicated."
-    :type '(choice (const :tag "No wrap types" nil)
-                  (alist :tag "Alist of node types"
-                         :key-type (symbol :tag "Language")
-                         :value-type (repeat :tag "Types" (symbol :tag 
"Type"))))
-    :group 'indent-bars)
-
-(defcustom indent-bars-treesit-ignore-blank-lines-types nil
-  "Do not style blank lines when the type of node at start is in this list.
-Either nil, or a list of node type strings to avoid adding blank
-line styling to.  Typically \"top-level\" node types like
-\"module\", \"program\", and \"translation_unit\" would be used
-here, and they need not be valid types for any particular
-grammar.  Only applicable if `indent-bars-display-on-blank-lines'
-is set."
-  :type '(choice (const :tag "None" nil)
-                (repeat :tag "Node types" string))
-  :group 'indent-bars)
-
-(defcustom indent-bars-no-descend-string 'string
-  "Configure bar behavior inside strings.
-If non-nil, set to a symbol naming a tree-sitter string node type
-into which bars will go no deeper than their starting line.  If
-this node type is invalid, a message is printed and the feature
-is disabled."
-  :local t
-  :type '(choice (const :tag "Disable" nil) (symbol :tag "Node Type"))
-  :group 'indent-bars)
-
 ;;;; Colors
 (defvar indent-bars--main-color nil)
 (defvar indent-bars--depth-palette nil)
@@ -632,6 +596,26 @@ Note that the first bar is expected at 
`indent-bars-starting-column'."
        ((> len 0) 1)
        (t 0)))
 
+(defvar indent-bars--update-depth-function nil)
+(defun indent-bars--current-indentation-depth (&optional on-bar)
+  "Calculate current indentation depth.
+If ON-BAR is non-nil, report a line with content beginning on a
+bar position at that position.  If treesit support is enabled,
+searches for parent nodes with types specified in
+`indent-bars-treesit-wrap' for the current buffer's language,
+and, if found, limits the indentation depth to one more than the
+topmost matching parent node's initial line's indentation depth.
+If `indent-bars-no-descend-string' is non-nil, also look for
+enclosing string and mark indent depth no deeper than one more
+than the starting line's depth."
+  (let* ((c (current-indentation))
+        (d (indent-bars--depth c)))
+    (if indent-bars--update-depth-function
+       (setq d (funcall indent-bars--update-depth-function d)))
+    (if (and on-bar (= c (+ indent-bars--offset (* d indent-bars-spacing))))
+       (1+ d) d)))
+
+
 (defun indent-bars--blank-string (off nbars bar-from &optional width)
   "Return a blank string with bars displayed.
 OFF is character offset for the first bar, NBARS is the desired
@@ -848,75 +832,6 @@ see `indent-bars-prefer-character')."
                        (propertize (string indent-bars-no-stipple-char)
                                    'face (indent-bars--face d))))))))
 
-;;;; Tree-sitter
-(defvar-local indent-bars--ts-parser nil)
-(defvar-local indent-bars--ts-query nil)
-(defvar-local indent-bars--ts-string-query nil)
-
-(defun indent-bars--ts-node-query (node query &optional start-only 
first-spanning)
-  "Capture node(s) spanning NODE matching QUERY.
-QUERY is a compiled treesit query.  If START-ONLY is non-nil, the
-query searches for matching nodes spanning the start of the node
-at point.  If FIRST-SPANNING is non-nil, return the first
-matching node, but only if it fully spans the start and end range
-of NODE."
-  (let* ((start (treesit-node-start node))
-        (end (if start-only start (treesit-node-end node)))
-        (nodes (treesit-query-capture indent-bars--ts-parser query
-                                      start end t)))
-    (when (and first-spanning nodes)
-      (let ((n (car nodes)))
-       (setq nodes
-             (and (<= (treesit-node-start n) start)
-                  (>= (treesit-node-end n) end)
-                  n))))
-    nodes))
-
-(defsubst indent-bars--indent-at-node (node)
-  "Return the current indentation at the start of NODE."
-  (save-excursion
-    (goto-char (treesit-node-start node))
-    (current-indentation)))
-
-(defun indent-bars--current-indentation-depth (&optional on-bar)
-  "Calculate current indentation depth.
-If ON-BAR is non-nil, report a line with content beginning on a
-bar position at that position.  If treesit support is enabled,
-searches for parent nodes with types specified in
-`indent-bars-treesit-wrap' for the current buffer's language,
-and, if found, limits the indentation depth to one more than the
-topmost matching parent node's initial line's indentation depth.
-If `indent-bars-no-descend-string' is non-nil, also look for
-enclosing string and mark indent depth no deeper than one more
-than the starting line's depth."
-  (let* ((c (current-indentation))
-        (d (indent-bars--depth c))
-        (p (point))
-        (dnew (when-let ((indent-bars--ts-query)
-                         ((/= p (point-min)))
-                         (node (treesit-node-on (1- p) p 
indent-bars--ts-parser)))
-                (if (and indent-bars-no-descend-string
-                         (indent-bars--ts-node-query
-                          node indent-bars--ts-string-query t))
-                    (1+ (indent-bars--depth (indent-bars--indent-at-node 
node)))
-                  (when-let ((ctx (indent-bars--ts-node-query
-                                   node indent-bars--ts-query nil t)))
-                    (1+ (indent-bars--depth
-                         (indent-bars--indent-at-node ctx))))))))
-    (if dnew (setq d (min dnew d)))
-    (if (and on-bar (= c (+ indent-bars--offset (* d indent-bars-spacing))))
-       (1+ d) d)))
-
-(defun indent-bars--ignore-blank (beg)
-  "See if blank lines at BEG should be ignored using tree-sitter.
-Blank lines to ignore are those with types in
-`indent-bars-treesit-ignore-blank-lines-types'."
-  (and indent-bars--ts-parser
-       indent-bars-treesit-ignore-blank-lines-types
-       (when-let ((n (treesit-node-on beg beg)))
-        (seq-contains-p indent-bars-treesit-ignore-blank-lines-types
-                        (treesit-node-type n)))))
-
 ;;;; Font Lock
 (defvar-local indent-bars--font-lock-keywords nil)
 (defvar indent-bars--font-lock-blank-line-keywords nil)
@@ -948,18 +863,14 @@ the surrounding line indentation to determine additional 
bars to
 display on each line, using `indent-bars--draw-line'.
 
 Note: blank lines at the very beginning or end of the buffer are
-not indicated, even if otherwise they would be.  If
-`indent-bars-treesit-ignore-blank-lines-types' is configured,
-ignore blank lines whose starting positions are directly spanned
-by nodes of those types (e.g. module)."
+not indicated, even if they otherwise would be."
   (let* ((beg (match-beginning 0))
         (end (match-end 0))
         ctxbars)
     (save-excursion
       (goto-char (1- beg))
       (beginning-of-line 1)
-      (when (and (not (indent-bars--ignore-blank beg))
-                (> (setq ctxbars (indent-bars--context-bars end)) 0))
+      (when (> (setq ctxbars (indent-bars--context-bars end)) 0)
        (goto-char beg)
        (while (< (point) end) ;note: end extends 1 char beyond blank line range
          (let* ((bp (line-beginning-position))
@@ -1176,28 +1087,6 @@ Adapted from `highlight-indentation-mode'."
   ;; Window state: selection/size
   (add-hook 'window-state-change-functions #'indent-bars--window-change nil t)
 
-  ;; Treesitter
-  (when-let (((and indent-bars-treesit-support
-                  (fboundp #'treesit-available-p)
-                  (treesit-available-p)))
-            (lang (treesit-language-at (point-min)))
-            (types (alist-get lang indent-bars-treesit-wrap)))
-    (setq indent-bars--ts-parser
-         (cl-find lang (treesit-parser-list) :key #'treesit-parser-language)
-         indent-bars--ts-query
-         (treesit-query-compile lang `([,@(mapcar #'list types)] @ctx)))
-    (when indent-bars-no-descend-string
-      (let ((query `([(,indent-bars-no-descend-string)] @s))
-           (pm (point-min)))
-       (setq indent-bars--ts-string-query (treesit-query-compile lang query))
-       ;; Test it to be sure
-       (condition-case err
-           (treesit-query-capture indent-bars--ts-parser
-                                  indent-bars--ts-string-query pm pm t)
-         (treesit-query-error
-          (setq indent-bars-no-descend-string nil)
-          (message "indent-bars: malformed string query; disabling.  See 
indent-bars-no-descend-string.\n%s" err))))))
-
   ;; Current depth highlight
   (when indent-bars-highlight-current-depth
     (indent-bars--set-current-bg-color)
@@ -1211,6 +1100,9 @@ Adapted from `highlight-indentation-mode'."
   (add-hook 'text-scale-mode-hook #'indent-bars--resize-stipple nil t)
   (indent-bars--resize-stipple)                ; just in case
 
+  ;; Treesitter
+  (if indent-bars-treesit-support (indent-bars-ts-setup))
+  
   ;; Font-lock
   (indent-bars--setup-font-lock)
   (font-lock-flush))