feat(ai-vterm): add Claude launcher with vertical-split vterm

The new module picks a Claude-template project from a filtered completing-read list. It scans the same roots the `ai` shell launcher uses, then opens or reuses a vterm buffer named `claude [<repo>]` on the right. F9 launches it. The prior `cj/toggle-gptel` binding moves from F9 to C-F9 so both AI tools share the same physical key.

The display rule chains reuse-window -> use-some-window -> in-direction (right). The resulting window isn't dedicated. That matters because side-window dedication was breaking `buffer-move` (C-M-arrows) and `switch-to-buffer` replacement on the claude buffer. I also narrowed `vterm-toggle`'s display rule to skip `claude [` buffers. Otherwise it claimed them first with its bottom-split + dedicated treatment.

I added 23 tests across 5 files: the buffer-name transform, candidate walker, show-or-create dispatch, picker, and display rule. Design lives at docs/design/ai-vterm.org.

1 files changed, 139 insertions, 0 deletions

diff --git a/tests/test-ai-vterm--candidates.el b/tests/test-ai-vterm--candidates.el
new file mode 100644
index 000000000..b45888cc7
--- /dev/null
+++ b/tests/test-ai-vterm--candidates.el
@@ -0,0 +1,139 @@
+;;; test-ai-vterm--candidates.el --- Tests for cj/--ai-vterm-candidates -*- lexical-binding: t; -*-
+
+;;; Commentary:
+;; Tests for the project-candidate walker.  Two kinds of search root:
+;;
+;; - project root  (a single project dir, e.g. ~/.emacs.d) -- include if it
+;;   itself contains .ai/protocols.org
+;; - container root (e.g. ~/code, ~/projects) -- scan immediate children;
+;;   include each child that contains .ai/protocols.org
+;;
+;; Tests build a temp directory tree with fake .ai/protocols.org markers
+;; and let-bind the search-root customs at it.
+
+;;; Code:
+
+(require 'ert)
+
+(add-to-list 'load-path (expand-file-name "modules" user-emacs-directory))
+(require 'ai-vterm)
+
+(defun test-ai-vterm--make-marker (dir)
+  "Create DIR/.ai/protocols.org so DIR registers as a Claude project."
+  (let ((ai-dir (expand-file-name ".ai" dir)))
+    (make-directory ai-dir t)
+    (write-region "" nil (expand-file-name "protocols.org" ai-dir))))
+
+(defmacro test-ai-vterm--with-fixture (root &rest body)
+  "Bind ROOT to a fresh temp directory; remove on exit; run BODY."
+  (declare (indent 1) (debug t))
+  `(let ((,root (make-temp-file "ai-vterm-test-" t)))
+     (unwind-protect
+         (progn ,@body)
+       (delete-directory ,root t))))
+
+(ert-deftest test-ai-vterm--candidates-project-root-with-marker ()
+  "Normal: a project root containing .ai/protocols.org is included."
+  (test-ai-vterm--with-fixture root
+    (let ((proj (expand-file-name "emacs-d-fake" root)))
+      (make-directory proj)
+      (test-ai-vterm--make-marker proj)
+      (let ((cj/ai-vterm-project-roots (list proj))
+            (cj/ai-vterm-container-roots nil))
+        (should (equal (cj/--ai-vterm-candidates)
+                       (list (expand-file-name proj))))))))
+
+(ert-deftest test-ai-vterm--candidates-project-root-without-marker ()
+  "Boundary: a project root without .ai/protocols.org is excluded."
+  (test-ai-vterm--with-fixture root
+    (let ((proj (expand-file-name "no-ai" root)))
+      (make-directory proj)
+      (let ((cj/ai-vterm-project-roots (list proj))
+            (cj/ai-vterm-container-roots nil))
+        (should (null (cj/--ai-vterm-candidates)))))))
+
+(ert-deftest test-ai-vterm--candidates-container-includes-children-with-marker ()
+  "Normal: a container's children with .ai/protocols.org are included."
+  (test-ai-vterm--with-fixture root
+    (let ((container (expand-file-name "code" root))
+          (foo (expand-file-name "code/foo" root))
+          (bar (expand-file-name "code/bar" root)))
+      (make-directory container)
+      (make-directory foo)
+      (make-directory bar)
+      (test-ai-vterm--make-marker foo)
+      (test-ai-vterm--make-marker bar)
+      (let* ((cj/ai-vterm-project-roots nil)
+             (cj/ai-vterm-container-roots (list container))
+             (got (sort (cj/--ai-vterm-candidates) #'string<)))
+        (should (equal got
+                       (sort (list (expand-file-name foo)
+                                   (expand-file-name bar))
+                             #'string<)))))))
+
+(ert-deftest test-ai-vterm--candidates-container-skips-children-without-marker ()
+  "Boundary: a container's children without .ai/protocols.org are skipped."
+  (test-ai-vterm--with-fixture root
+    (let ((container (expand-file-name "code" root))
+          (foo (expand-file-name "code/foo" root))
+          (bare (expand-file-name "code/bare" root)))
+      (make-directory container)
+      (make-directory foo)
+      (make-directory bare)
+      (test-ai-vterm--make-marker foo)
+      (let ((cj/ai-vterm-project-roots nil)
+            (cj/ai-vterm-container-roots (list container)))
+        (should (equal (cj/--ai-vterm-candidates)
+                       (list (expand-file-name foo))))))))
+
+(ert-deftest test-ai-vterm--candidates-container-skips-non-directory-entries ()
+  "Boundary: a container's non-directory entries are ignored."
+  (test-ai-vterm--with-fixture root
+    (let ((container (expand-file-name "code" root))
+          (foo (expand-file-name "code/foo" root))
+          (stray (expand-file-name "code/README.txt" root)))
+      (make-directory container)
+      (make-directory foo)
+      (test-ai-vterm--make-marker foo)
+      (write-region "" nil stray)
+      (let ((cj/ai-vterm-project-roots nil)
+            (cj/ai-vterm-container-roots (list container)))
+        (should (equal (cj/--ai-vterm-candidates)
+                       (list (expand-file-name foo))))))))
+
+(ert-deftest test-ai-vterm--candidates-nonexistent-root-is-skipped ()
+  "Error: a nonexistent search root is skipped silently, no error raised."
+  (test-ai-vterm--with-fixture root
+    (let ((cj/ai-vterm-project-roots
+           (list (expand-file-name "does-not-exist" root)))
+          (cj/ai-vterm-container-roots
+           (list (expand-file-name "also-missing" root))))
+      (should (null (cj/--ai-vterm-candidates))))))
+
+(ert-deftest test-ai-vterm--candidates-empty-roots-yield-empty-list ()
+  "Boundary: nil roots yield nil."
+  (let ((cj/ai-vterm-project-roots nil)
+        (cj/ai-vterm-container-roots nil))
+    (should (null (cj/--ai-vterm-candidates)))))
+
+(ert-deftest test-ai-vterm--candidates-mixed-roots ()
+  "Normal: project + container roots combine in one result list."
+  (test-ai-vterm--with-fixture root
+    (let ((emacs-d (expand-file-name "emacs-d" root))
+          (container (expand-file-name "code" root))
+          (foo (expand-file-name "code/foo" root)))
+      (make-directory emacs-d)
+      (make-directory container)
+      (make-directory foo)
+      (test-ai-vterm--make-marker emacs-d)
+      (test-ai-vterm--make-marker foo)
+      (let* ((cj/ai-vterm-project-roots (list emacs-d))
+             (cj/ai-vterm-container-roots (list container))
+             (got (sort (cj/--ai-vterm-candidates) #'string<)))
+        (should (equal got
+                       (sort (list (expand-file-name emacs-d)
+                                   (expand-file-name foo))
+                             #'string<)))))))
+
+(provide 'test-ai-vterm--candidates)
+;;; test-ai-vterm--candidates.el ends here