feature/tree-sitter 6fde1fcd0f: Separate tree-sitter and non-tree-sitter variant of sh-mode

[Yuan Fu]

branch: feature/tree-sitter
commit 6fde1fcd0fb5111f3262e5ff829b19ec9f136d90
Author: Yuan Fu <casouri@gmail.com>
Commit: Yuan Fu <casouri@gmail.com>

    Separate tree-sitter and non-tree-sitter variant of sh-mode
    
    Now there are three modes, sh-base-mode, sh-mode, bash-ts-mode.
    
    The change I made: change sh-mode to sh-base-mode, remove docstring.
    Below the new sh-base-mode, create a new definition for sh-mode, paste
    the dostring, add setup for font-lock-defaults.  Below sh-mode, add
    bash-ts-mode.
    
    * lisp/progmodes/sh-script.el (sh-mode): Moves all setup into
    sh-base-mode, except for the setup for font-lock-defaults and the
    docstring.
    (sh-base-mode): New mode.
    (bash-ts-mode): New mode.
---
 lisp/progmodes/sh-script.el | 142 +++++++++++++++++++++++---------------------
 1 file changed, 74 insertions(+), 68 deletions(-)

diff --git a/lisp/progmodes/sh-script.el b/lisp/progmodes/sh-script.el
index 54f005508c..7fe31802c4 100644
--- a/lisp/progmodes/sh-script.el
+++ b/lisp/progmodes/sh-script.el
@@ -1469,57 +1469,12 @@ When the region is active, send the region instead."
 (defvar sh-mode--treesit-settings)
 
 ;;;###autoload
-(define-derived-mode sh-mode prog-mode "Shell-script"
-  "Major mode for editing shell scripts.
-This mode works for many shells, since they all have roughly the same syntax,
-as far as commands, arguments, variables, pipes, comments etc. are concerned.
-Unless the file's magic number indicates the shell, your usual shell is
-assumed.  Since filenames rarely give a clue, they are not further analyzed.
-
-This mode adapts to the variations between shells (see `sh-set-shell') by
-means of an inheritance based feature lookup (see `sh-feature').  This
-mechanism applies to all variables (including skeletons) that pertain to
-shell-specific features.  Shell script files can use the `sh-shell' local
-variable to indicate the shell variant to be used for the file.
-
-The default style of this mode is that of Rosenblatt's Korn shell book.
-The syntax of the statements varies with the shell being used.  The
-following commands are available, based on the current shell's syntax:
-\\<sh-mode-map>
-\\[sh-case]     case statement
-\\[sh-for]      for loop
-\\[sh-function]         function definition
-\\[sh-if]       if statement
-\\[sh-indexed-loop]     indexed loop from 1 to n
-\\[sh-while-getopts]    while getopts loop
-\\[sh-repeat]   repeat loop
-\\[sh-select]   select loop
-\\[sh-until]    until loop
-\\[sh-while]    while loop
-
-For sh and rc shells indentation commands are:
-\\[smie-config-show-indent]    Show the rules controlling this line's 
indentation.
-\\[smie-config-set-indent]     Change the rules controlling this line's 
indentation.
-\\[smie-config-guess]  Try to tweak the indentation rules so the
-buffer indents as it currently is indented.
-
-
-\\[backward-delete-char-untabify]       Delete backward one position, even if 
it was a tab.
-\\[sh-end-of-command]   Go to end of successive commands.
-\\[sh-beginning-of-command]     Go to beginning of successive commands.
-\\[sh-set-shell]        Set this buffer's shell, and maybe its magic number.
-\\[sh-execute-region]   Have optional header and region be executed in a 
subshell.
-
-`sh-electric-here-document-mode' controls whether insertion of two
-unquoted < insert a here document.  You can control this behavior by
-modifying `sh-mode-hook'.
+(define-derived-mode sh-base-mode prog-mode "Shell-script"
+  "Generic major mode for editing shell scripts.
 
-If you generally program a shell different from your login shell you can
-set `sh-shell-file' accordingly.  If your shell's file name doesn't correctly
-indicate what shell it is use `sh-alias-alist' to translate.
-
-If your shell gives error messages with line numbers, you can use 
\\[executable-interpret]
-with your script for an edit-interpret-debug cycle."
+This is a generic major mode intended to be inherited by concrete
+implementations.  Currently there are two: `sh-mode' and
+`bash-ts-mode'."
   (make-local-variable 'sh-shell-file)
   (make-local-variable 'sh-shell)
 
@@ -1583,31 +1538,82 @@ with your script for an edit-interpret-debug cycle."
    nil nil)
   (add-hook 'flymake-diagnostic-functions #'sh-shellcheck-flymake nil t)
   (add-hook 'hack-local-variables-hook
-    #'sh-after-hack-local-variables nil t)
+            #'sh-after-hack-local-variables nil t))
 
-  (cond
-   ;; Tree-sitter.  If the shell is bash, we can enable tree-sitter.
-   ((treesit-ready-p sh-shell)
+;;;###autoload
+(define-derived-mode sh-mode sh-base-mode "Shell-script"
+  "Major mode for editing shell scripts.
+This mode works for many shells, since they all have roughly the same syntax,
+as far as commands, arguments, variables, pipes, comments etc. are concerned.
+Unless the file's magic number indicates the shell, your usual shell is
+assumed.  Since filenames rarely give a clue, they are not further analyzed.
+
+This mode adapts to the variations between shells (see `sh-set-shell') by
+means of an inheritance based feature lookup (see `sh-feature').  This
+mechanism applies to all variables (including skeletons) that pertain to
+shell-specific features.  Shell script files can use the `sh-shell' local
+variable to indicate the shell variant to be used for the file.
+
+The default style of this mode is that of Rosenblatt's Korn shell book.
+The syntax of the statements varies with the shell being used.  The
+following commands are available, based on the current shell's syntax:
+\\<sh-mode-map>
+\\[sh-case]     case statement
+\\[sh-for]      for loop
+\\[sh-function]         function definition
+\\[sh-if]       if statement
+\\[sh-indexed-loop]     indexed loop from 1 to n
+\\[sh-while-getopts]    while getopts loop
+\\[sh-repeat]   repeat loop
+\\[sh-select]   select loop
+\\[sh-until]    until loop
+\\[sh-while]    while loop
+
+For sh and rc shells indentation commands are:
+\\[smie-config-show-indent]    Show the rules controlling this line's 
indentation.
+\\[smie-config-set-indent]     Change the rules controlling this line's 
indentation.
+\\[smie-config-guess]  Try to tweak the indentation rules so the
+buffer indents as it currently is indented.
+
+
+\\[backward-delete-char-untabify]       Delete backward one position, even if 
it was a tab.
+\\[sh-end-of-command]   Go to end of successive commands.
+\\[sh-beginning-of-command]     Go to beginning of successive commands.
+\\[sh-set-shell]        Set this buffer's shell, and maybe its magic number.
+\\[sh-execute-region]   Have optional header and region be executed in a 
subshell.
+
+`sh-electric-here-document-mode' controls whether insertion of two
+unquoted < insert a here document.  You can control this behavior by
+modifying `sh-mode-hook'.
+
+If you generally program a shell different from your login shell you can
+set `sh-shell-file' accordingly.  If your shell's file name doesn't correctly
+indicate what shell it is use `sh-alias-alist' to translate.
+
+If your shell gives error messages with line numbers, you can use 
\\[executable-interpret]
+with your script for an edit-interpret-debug cycle."
+  (setq font-lock-defaults
+        `((sh-font-lock-keywords
+           sh-font-lock-keywords-1 sh-font-lock-keywords-2)
+          nil nil
+          ((?/ . "w") (?~ . "w") (?. . "w") (?- . "w") (?_ . "w")) nil
+          (font-lock-syntactic-face-function
+           . ,#'sh-font-lock-syntactic-face-function))))
+
+;;;###autoload
+(defalias 'shell-script-mode 'sh-mode)
+
+;;;###autoload
+(define-derived-mode bash-ts-mode sh-base-mode "Bash"
+  "Major mode for editing Bash shell scripts."
+  (when (treesit-ready-p 'bash)
     (setq-local treesit-font-lock-feature-list
                 '((comment function string heredoc)
                   (variable keyword command declaration-command)
                   (constant operator builtin-variable)))
     (setq-local treesit-font-lock-settings
                 sh-mode--treesit-settings)
-    (treesit-major-mode-setup))
-   ;; Elisp.
-   (t
-    (setq font-lock-defaults
-          `((sh-font-lock-keywords
-             sh-font-lock-keywords-1 sh-font-lock-keywords-2)
-            nil nil
-            ((?/ . "w") (?~ . "w") (?. . "w") (?- . "w") (?_ . "w")) nil
-            (font-lock-syntactic-face-function
-             . ,#'sh-font-lock-syntactic-face-function))))))
-
-;;;###autoload
-(defalias 'shell-script-mode 'sh-mode)
-
+    (treesit-major-mode-setup)))
 
 (defun sh-font-lock-keywords (&optional keywords)
   "Function to get simple fontification based on `sh-font-lock-keywords'.