test(gptel): add unit tests for ai-config, remove dead cj/gptel-backends

- Add testutil-ai-config.el with gptel stubs for batch testing
- Add tests for cj/gptel--model-to-string (9 tests)
- Add tests for cj/gptel--fresh-org-prefix (8 tests)
- Add tests for cj/gptel-backend-and-model (8 tests)
- Remove dead cj/gptel-backends defvar (duplicates cj/gptel--available-backends)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

1 files changed, 65 insertions, 0 deletions

diff --git a/tests/test-ai-config-fresh-org-prefix.el b/tests/test-ai-config-fresh-org-prefix.el
new file mode 100644
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+++ b/tests/test-ai-config-fresh-org-prefix.el
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+;;; test-ai-config-fresh-org-prefix.el --- Tests for cj/gptel--fresh-org-prefix -*- lexical-binding: t; -*-
+
+;;; Commentary:
+;; Tests for cj/gptel--fresh-org-prefix from ai-config.el.
+;;
+;; Generates an org-mode level-1 heading containing the user's login
+;; name and a bracketed timestamp, used as the user message prefix in
+;; gptel org-mode conversations.
+
+;;; Code:
+
+(require 'ert)
+
+(add-to-list 'load-path (expand-file-name "tests" user-emacs-directory))
+(add-to-list 'load-path (expand-file-name "modules" user-emacs-directory))
+(require 'testutil-ai-config)
+(require 'ai-config)
+
+;;; Normal Cases
+
+(ert-deftest test-ai-config-fresh-org-prefix-normal-starts-with-org-heading ()
+  "Result should start with '* ' for an org level-1 heading."
+  (should (string-prefix-p "* " (cj/gptel--fresh-org-prefix))))
+
+(ert-deftest test-ai-config-fresh-org-prefix-normal-contains-username ()
+  "Result should contain the current user's login name."
+  (should (string-match-p (regexp-quote user-login-name)
+                          (cj/gptel--fresh-org-prefix))))
+
+(ert-deftest test-ai-config-fresh-org-prefix-normal-contains-timestamp ()
+  "Result should contain a bracketed timestamp in YYYY-MM-DD HH:MM:SS format."
+  (should (string-match-p "\\[[-0-9]+ [0-9]+:[0-9]+:[0-9]+\\]"
+                          (cj/gptel--fresh-org-prefix))))
+
+(ert-deftest test-ai-config-fresh-org-prefix-normal-ends-with-newline ()
+  "Result should end with a newline."
+  (should (string-suffix-p "\n" (cj/gptel--fresh-org-prefix))))
+
+(ert-deftest test-ai-config-fresh-org-prefix-normal-format-order ()
+  "Result should have star, then username, then timestamp in order."
+  (let ((result (cj/gptel--fresh-org-prefix)))
+    (should (string-match
+             (format "^\\* %s \\[" (regexp-quote user-login-name))
+             result))))
+
+;;; Boundary Cases
+
+(ert-deftest test-ai-config-fresh-org-prefix-boundary-timestamp-reflects-today ()
+  "Timestamp should contain today's date."
+  (let ((today (format-time-string "%Y-%m-%d")))
+    (should (string-match-p (regexp-quote today)
+                            (cj/gptel--fresh-org-prefix)))))
+
+(ert-deftest test-ai-config-fresh-org-prefix-boundary-overridden-username ()
+  "Result should reflect a dynamically-bound user-login-name."
+  (let ((user-login-name "testuser"))
+    (should (string-match-p "testuser" (cj/gptel--fresh-org-prefix)))))
+
+(ert-deftest test-ai-config-fresh-org-prefix-boundary-empty-username ()
+  "Empty user-login-name should produce heading with empty name slot."
+  (let ((user-login-name ""))
+    (should (string-match-p "^\\*  \\[" (cj/gptel--fresh-org-prefix)))))
+
+(provide 'test-ai-config-fresh-org-prefix)
+;;; test-ai-config-fresh-org-prefix.el ends here