feat: add indent settings

Author: damienbutt

netlinx-mode-indent.el

@@ -0,0 +1,59 @@
+;;; netlinx-mode-indent.el --- Indent settings for NetLinx mode -*- lexical-binding: t; no-byte-compile: t; -*-
+
+;; Copyright (C) 2024 Norgate AV
+
+;; Author: Norgate AV
+;; Maintainer: Norgate AV
+
+;;; Commentary:
+
+;; This file provides indent settings for NetLinx mode.
+;; This is an internal library for netlinx-mode.el and is not a standalone package.
+
+;;; Code:
+
+;; Indentation rules for tree-sitter
+(defvar netlinx-mode--indent-rules
+  `((netlinx
+     ;; Closing delimiters align with their opening construct
+     ((node-is "}") parent-bol 0)
+     ((node-is ")") parent-bol 0)
+     ((node-is "]") parent-bol 0)
+
+     ;; Control flow keywords align with their parent
+     ((node-is "else_clause") parent-bol 0)
+     ((node-is "case_statement") parent-bol netlinx-mode-indent-offset)
+     ((node-is "default_label") parent-bol netlinx-mode-indent-offset)
+
+     ;; Statement blocks are indented
+     ((parent-is "if_statement") parent-bol netlinx-mode-indent-offset)
+     ((parent-is "for_statement") parent-bol netlinx-mode-indent-offset)
+     ((parent-is "while_statement") parent-bol netlinx-mode-indent-offset)
+     ((parent-is "switch_statement") parent-bol netlinx-mode-indent-offset)
+     ((parent-is "case_statement") parent-bol netlinx-mode-indent-offset)
+     ((parent-is "else_clause") parent-bol netlinx-mode-indent-offset)
+     ((parent-is "select_statement") parent-bol netlinx-mode-indent-offset)
+     ((parent-is "active_statement") parent-bol netlinx-mode-indent-offset)
+
+     ;; Function and event definitions
+     ((parent-is "define_function") parent-bol netlinx-mode-indent-offset)
+     ((parent-is "function_definition") parent-bol netlinx-mode-indent-offset)
+     ((parent-is "event_handler") parent-bol netlinx-mode-indent-offset)
+
+     ;; Compound statements
+     ((parent-is "compound_statement") parent-bol netlinx-mode-indent-offset)
+
+     ;; Array and struct initializers
+     ((parent-is "initializer_list") parent-bol netlinx-mode-indent-offset)
+
+     ;; Parameter lists
+     ((parent-is "parameter_list") parent-bol netlinx-mode-indent-offset)
+     ((parent-is "argument_list") parent-bol netlinx-mode-indent-offset)
+
+     ;; Default: maintain current indentation for other nodes
+     (no-node parent-bol 0)))
+  "Tree-sitter indentation rules for `netlinx-mode'.")
+
+(provide 'netlinx-mode-indent)
+
+;;; netlinx-mode-indent.el ends here

netlinx-mode.el

@@ -39,13 +39,23 @@
 ;; Load font-lock (syntax highlighting) settings
 (require 'netlinx-mode-font-lock)
 
+;; Load indentation settings
+(require 'netlinx-mode-indent)
+
 ;; Configuration for tree-sitter grammar
 (defcustom netlinx-mode-grammar-location
   "https://github.com/Norgate-AV/tree-sitter-netlinx"
   "Repository URL for the tree-sitter NetLinx grammar."
   :type 'string
   :group 'netlinx)
 
+;; Indentation configuration
+(defcustom netlinx-mode-indent-offset 4
+  "Number of spaces for each indentation step in `netlinx-mode'."
+  :type 'integer
+  :safe 'integerp
+  :group 'netlinx)
+
 ;; Specify the version/tag of the grammar to use
 (defcustom netlinx-mode-grammar-version
   "v1.0.4"
@@ -106,6 +116,18 @@ The file path is configured via `netlinx-mode-help-file'."
         ;; Create parser
         (treesit-parser-create 'netlinx)
 
+        ;; Comments
+        (setq-local comment-start "// ")
+        (setq-local comment-end "")
+        (setq-local comment-start-skip "//+\\s-*")
+        (setq-local comment-multi-line t)
+
+        ;; Indentation
+        (setq-local treesit-simple-indent-rules netlinx-mode--indent-rules)
+        (setq-local indent-line-function #'treesit-indent)
+        (setq-local electric-indent-chars
+                    (append "{}():;," electric-indent-chars))
+
         ;; Setup font-lock
         (setq-local treesit-font-lock-settings netlinx-mode--font-lock-settings)
         (setq-local treesit-font-lock-level 4)

test/netlinx-mode-test.el

@@ -22,8 +22,11 @@
   (should (custom-variable-p 'netlinx-mode-grammar-location))
   (should (custom-variable-p 'netlinx-mode-grammar-version))
   (should (custom-variable-p 'netlinx-mode-help-file))
+  (should (custom-variable-p 'netlinx-mode-indent-offset))
   (should (stringp netlinx-mode-grammar-location))
-  (should (stringp netlinx-mode-grammar-version)))
+  (should (stringp netlinx-mode-grammar-version))
+  (should (integerp netlinx-mode-indent-offset))
+  (should (= netlinx-mode-indent-offset 4)))
 
 ;;; Face Tests
 
@@ -122,6 +125,67 @@
   "Test that the package provides the netlinx-mode feature."
   (should (featurep 'netlinx-mode)))
 
+;;; Indentation Tests
+
+(ert-deftest netlinx-mode-test-indent-rules-defined ()
+  "Test that indentation rules are defined."
+  (should (boundp 'netlinx-mode--indent-rules))
+  (should (listp netlinx-mode--indent-rules))
+  (should (assq 'netlinx netlinx-mode--indent-rules)))
+
+(ert-deftest netlinx-mode-test-indent-offset-safe ()
+  "Test that indent-offset has a safety predicate."
+  (should (get 'netlinx-mode-indent-offset 'safe-local-variable))
+  (should (funcall (get 'netlinx-mode-indent-offset 'safe-local-variable) 4))
+  (should (funcall (get 'netlinx-mode-indent-offset 'safe-local-variable) 2))
+  (should-not (funcall (get 'netlinx-mode-indent-offset 'safe-local-variable) "not-a-number")))
+
+(ert-deftest netlinx-mode-test-indent-configuration ()
+  "Test that indentation is configured when mode is activated."
+  (with-temp-buffer
+    (cl-letf (((symbol-function 'netlinx-mode--ensure-grammar) #'ignore)
+              ((symbol-function 'treesit-ready-p) (lambda (&rest _) t))
+              ((symbol-function 'treesit-parser-create) #'ignore)
+              ((symbol-function 'treesit-major-mode-setup) #'ignore))
+      (netlinx-mode)
+      (should (local-variable-p 'treesit-simple-indent-rules))
+      (should (eq treesit-simple-indent-rules netlinx-mode--indent-rules)))))
+
+;;; Comment Configuration Tests
+
+(ert-deftest netlinx-mode-test-comment-start ()
+  "Test that comment-start is configured correctly."
+  (with-temp-buffer
+    (cl-letf (((symbol-function 'netlinx-mode--ensure-grammar) #'ignore)
+              ((symbol-function 'treesit-ready-p) (lambda (&rest _) t))
+              ((symbol-function 'treesit-parser-create) #'ignore)
+              ((symbol-function 'treesit-major-mode-setup) #'ignore))
+      (netlinx-mode)
+      (should (local-variable-p 'comment-start))
+      (should (string= comment-start "// ")))))
+
+(ert-deftest netlinx-mode-test-comment-end ()
+  "Test that comment-end is configured correctly."
+  (with-temp-buffer
+    (cl-letf (((symbol-function 'netlinx-mode--ensure-grammar) #'ignore)
+              ((symbol-function 'treesit-ready-p) (lambda (&rest _) t))
+              ((symbol-function 'treesit-parser-create) #'ignore)
+              ((symbol-function 'treesit-major-mode-setup) #'ignore))
+      (netlinx-mode)
+      (should (local-variable-p 'comment-end))
+      (should (string= comment-end "")))))
+
+(ert-deftest netlinx-mode-test-comment-start-skip ()
+  "Test that comment-start-skip is configured correctly."
+  (with-temp-buffer
+    (cl-letf (((symbol-function 'netlinx-mode--ensure-grammar) #'ignore)
+              ((symbol-function 'treesit-ready-p) (lambda (&rest _) t))
+              ((symbol-function 'treesit-parser-create) #'ignore)
+              ((symbol-function 'treesit-major-mode-setup) #'ignore))
+      (netlinx-mode)
+      (should (local-variable-p 'comment-start-skip))
+      (should (stringp comment-start-skip)))))
+
 (provide 'netlinx-mode-test)
 
 ;;; netlinx-mode-test.el ends here