refactor(eshell): move SSH-jump hosts into a defcustom

The eshell SSH-jump aliases (gocj, gosb, gowolf) were hardcoded inline in the alias setup, which tied the module to my machines. I moved them into a cj/eshell-ssh-hosts defcustom (an alias→remote-path alist, defaulting to my current hosts) and build the aliases by iterating it. A different machine can override the variable or set it to nil instead of editing the module. Extracted a pure cj/--eshell-ssh-alias-commands helper so the alias construction is testable without a live eshell.

2 files changed, 82 insertions, 3 deletions

diff --git a/modules/eshell-config.el b/modules/eshell-config.el
index 64bc88c6..0439a467 100644
--- a/modules/eshell-config.el
+++ b/modules/eshell-config.el
@@ -26,6 +26,37 @@
 
 (require 'system-utils)
 
+(defgroup cj/eshell nil
+  "Personal Eshell configuration."
+  :group 'eshell)
+
+(defcustom cj/eshell-ssh-hosts
+  '(("gocj"   . "/sshx:cjennings@cjennings.net:/var/cjennings/")
+    ("gosb"   . "/sshx:cjennings@wolf.usbx.me:/home/cjennings/")
+    ("gowolf" . "/sshx:cjennings@wolf.usbx.me:/home/cjennings/"))
+  "Alist of Eshell SSH-jump aliases.
+Each entry is a cons cell (ALIAS-NAME . REMOTE-PATH).  At Eshell
+startup an alias named ALIAS-NAME is defined that runs `cd' to the
+given TRAMP REMOTE-PATH.  Override on a different machine to point at
+your own hosts, or set to nil to define no SSH aliases."
+  :type '(alist :key-type (string :tag "Alias")
+                :value-type (string :tag "Remote path"))
+  :group 'cj/eshell)
+
+(defun cj/--eshell-ssh-alias-commands (hosts)
+  "Return the SSH alias definitions for HOSTS.
+HOSTS is an alist of (ALIAS-NAME . REMOTE-PATH) as in
+`cj/eshell-ssh-hosts'.  The result is a list of (ALIAS-NAME . COMMAND)
+pairs where COMMAND is the `cd' string `eshell/alias' should run."
+  (mapcar (lambda (entry)
+            (cons (car entry) (concat "cd " (cdr entry))))
+          hosts))
+
+(defun cj/--eshell-define-ssh-aliases (hosts)
+  "Define the Eshell SSH-jump aliases for HOSTS via `eshell/alias'."
+  (dolist (pair (cj/--eshell-ssh-alias-commands hosts))
+    (eshell/alias (car pair) (cdr pair))))
+
 (use-package eshell
   :ensure nil ;; built-in
   :commands (eshell)
@@ -79,9 +110,7 @@
 			  (eshell/alias "em"     "find-file $1")
 			  (eshell/alias "emacs"  "find-file $1")
 			  (eshell/alias "open"   "cj/xdg-open $1")
-			  (eshell/alias "gocj"   "cd /sshx:cjennings@cjennings.net:/var/cjennings/")
-			  (eshell/alias "gosb"   "cd /sshx:cjennings@wolf.usbx.me:/home/cjennings/")
-			  (eshell/alias "gowolf" "cd /sshx:cjennings@wolf.usbx.me:/home/cjennings/")
+			  (cj/--eshell-define-ssh-aliases cj/eshell-ssh-hosts)
 			  (eshell/alias "v"      "eshell-exec-visual $*")
 			  (eshell/alias "ff"     "find-file-other-window $1")
 			  (eshell/alias "f"      "find-using-dired $1")
diff --git a/tests/test-eshell-config-ssh-aliases.el b/tests/test-eshell-config-ssh-aliases.el
new file mode 100644
index 00000000..8d30801f
--- /dev/null
+++ b/tests/test-eshell-config-ssh-aliases.el
@@ -0,0 +1,50 @@
+;;; test-eshell-config-ssh-aliases.el --- Tests for eshell SSH alias building -*- lexical-binding: t; -*-
+
+;;; Commentary:
+;; Tests for cj/--eshell-ssh-alias-commands from eshell-config.el.
+;;
+;; The helper takes the `cj/eshell-ssh-hosts' alist of (ALIAS-NAME . REMOTE-PATH)
+;; and returns (ALIAS-NAME . COMMAND) pairs where COMMAND is the `cd' string
+;; `eshell/alias' runs.  Testing the pure helper avoids needing a live Eshell.
+
+;;; Code:
+
+(require 'ert)
+(require 'cl-lib)
+(require 'package)
+
+(setq package-user-dir (expand-file-name "elpa" user-emacs-directory))
+(package-initialize)
+(add-to-list 'load-path (expand-file-name "modules" user-emacs-directory))
+(require 'eshell-config)
+
+(declare-function cj/--eshell-ssh-alias-commands "eshell-config" (hosts))
+
+;;; Normal Cases
+
+(ert-deftest test-eshell-config-ssh-alias-commands-normal-two-hosts ()
+  "Normal: two hosts produce two cd-command alias pairs."
+  (let* ((hosts '(("gosb"   . "/sshx:cjennings@wolf.usbx.me:/home/cjennings/")
+                  ("gowolf" . "/sshx:cjennings@wolf.usbx.me:/home/cjennings/")))
+         (result (cj/--eshell-ssh-alias-commands hosts)))
+    (should (= 2 (length result)))
+    (should (equal (assoc "gosb" result)
+                   '("gosb" . "cd /sshx:cjennings@wolf.usbx.me:/home/cjennings/")))
+    (should (equal (assoc "gowolf" result)
+                   '("gowolf" . "cd /sshx:cjennings@wolf.usbx.me:/home/cjennings/")))))
+
+(ert-deftest test-eshell-config-ssh-alias-commands-normal-single-host ()
+  "Normal: a single host produces one pair, order preserved."
+  (let ((result (cj/--eshell-ssh-alias-commands
+                 '(("gocj" . "/sshx:cjennings@cjennings.net:/var/cjennings/")))))
+    (should (equal result
+                   '(("gocj" . "cd /sshx:cjennings@cjennings.net:/var/cjennings/"))))))
+
+;;; Boundary Cases
+
+(ert-deftest test-eshell-config-ssh-alias-commands-boundary-empty ()
+  "Boundary: an empty host list produces no SSH aliases."
+  (should (null (cj/--eshell-ssh-alias-commands '()))))
+
+(provide 'test-eshell-config-ssh-aliases)
+;;; test-eshell-config-ssh-aliases.el ends here.