Address some "unused lexical argument" warnings in eshell

* eshell/em-ls.el (eshell-ls-use-in-dired): Use `symbol' arg.
Fix (f)boundp mix-up.

* eshell/em-smart.el (eshell-smart-scroll-window)
(eshell-disable-after-change):
* eshell/em-term.el (eshell-term-sentinel): Mark unused arg.

3 files changed, 15 insertions, 14 deletions

diff --git a/lisp/eshell/em-ls.el b/lisp/eshell/em-ls.el
index 0e10d984f88..c2334d7bd74 100644
--- a/lisp/eshell/em-ls.el
+++ b/lisp/eshell/em-ls.el
@@ -50,9 +50,7 @@ properties to colorize its output based on the setting of
 
 (defcustom eshell-ls-unload-hook
   (list
-   (function
-    (lambda ()
-      (fset 'insert-directory eshell-ls-orig-insert-directory))))
+   (lambda () (fset 'insert-directory eshell-ls-orig-insert-directory)))
   "When unloading `eshell-ls', restore the definition of `insert-directory'."
   :type 'hook
   :group 'eshell-ls)
@@ -77,17 +75,17 @@ This is useful for enabling human-readable format (-h), for example."
   :type '(repeat :tag "Arguments" string)
   :group 'eshell-ls)
 
+;; FIXME should use advice, like ls-lisp.el does now.
 (defcustom eshell-ls-use-in-dired nil
-  "If non-nil, use `eshell-ls' to read directories in Dired."
+  "If non-nil, use `eshell-ls' to read directories in Dired.
+Changing this without using customize has no effect."
   :set (lambda (symbol value)
 	 (if value
-	     (unless (and (boundp 'eshell-ls-use-in-dired)
-			  eshell-ls-use-in-dired)
-	       (fset 'insert-directory 'eshell-ls-insert-directory))
-	   (when (and (boundp 'eshell-ls-insert-directory)
-		      eshell-ls-use-in-dired)
-	     (fset 'insert-directory eshell-ls-orig-insert-directory)))
-	 (setq eshell-ls-use-in-dired value))
+	     (or (bound-and-true-p eshell-ls-use-in-dired)
+		 (fset 'insert-directory 'eshell-ls-insert-directory))
+	   (and (fboundp 'eshell-ls-insert-directory) eshell-ls-use-in-dired
+		(fset 'insert-directory eshell-ls-orig-insert-directory)))
+	 (set symbol value))
   :type 'boolean
   :require 'em-ls
   :group 'eshell-ls)
diff --git a/lisp/eshell/em-smart.el b/lisp/eshell/em-smart.el
index e6fa463aec3..8d60444a889 100644
--- a/lisp/eshell/em-smart.el
+++ b/lisp/eshell/em-smart.el
@@ -194,7 +194,8 @@ The options are `begin', `after' or `end'."
       (add-hook 'eshell-post-command-hook
 		'eshell-smart-maybe-jump-to-end nil t))))
 
-(defun eshell-smart-scroll-window (wind start)
+;; This is called by window-scroll-functions with two arguments.
+(defun eshell-smart-scroll-window (wind _start)
   "Scroll the given Eshell window accordingly."
   (unless eshell-currently-handling-window
     (let ((inhibit-point-motion-hooks t)
@@ -237,7 +238,8 @@ The options are `begin', `after' or `end'."
   (add-hook 'pre-command-hook 'eshell-smart-display-move nil t)
   (eshell-refresh-windows))
 
-(defun eshell-disable-after-change (b e l)
+;; Called from after-change-functions with 3 arguments.
+(defun eshell-disable-after-change (_b _e _l)
   "Disable smart display mode if the buffer changes in any way."
   (when eshell-smart-command-done
     (remove-hook 'pre-command-hook 'eshell-smart-display-move t)
diff --git a/lisp/eshell/em-term.el b/lisp/eshell/em-term.el
index 71329f083ee..bfc810f2d2a 100644
--- a/lisp/eshell/em-term.el
+++ b/lisp/eshell/em-term.el
@@ -189,7 +189,8 @@ allowed."
 	  (term-set-escape-char ?\C-x))))
   nil)
 
-(defun eshell-term-sentinel (proc string)
+;; Process sentinels receive two arguments.
+(defun eshell-term-sentinel (proc _string)
   "Destroy the buffer visiting PROC."
   (let ((proc-buf (process-buffer proc)))
     (when (and proc-buf (buffer-live-p proc-buf)