fix(elfeed): bound and clean up the synchronous YouTube fetch

cj/youtube-to-elfeed-feed-format called url-retrieve-synchronously with no timeout, so a hung YouTube request would block Emacs indefinitely, and it only killed the temporary URL buffer when an ID was successfully extracted — a page without the expected markers leaked the buffer.

Passed cj/elfeed-url-fetch-timeout (10s) to the synchronous fetch, and moved the fetch+parse into an unwind-protect that always kills the temp buffer (live-p guarded), including the parse-failure path. Tests mock the network boundary and cover a normal channel parse, that a timeout is passed, and that the buffer is not leaked when parsing fails.

Also added tests for the EWW user-agent advice (no code change): it already injects the desktop UA only from eww-mode buffers, so package.el and other non-EWW url callers pass through untouched — the tests pin that scoping and the replace-not-duplicate header behavior.

1 files changed, 56 insertions, 0 deletions

diff --git a/tests/test-eww-config-user-agent-advice.el b/tests/test-eww-config-user-agent-advice.el
new file mode 100644
index 000000000..c045a5034
--- /dev/null
+++ b/tests/test-eww-config-user-agent-advice.el
@@ -0,0 +1,56 @@
+;;; test-eww-config-user-agent-advice.el --- Tests for EWW user-agent advice -*- lexical-binding: t; -*-
+
+;;; Commentary:
+;; my-eww--inject-user-agent is an :around advice on url-retrieve(-synchronously)
+;; that adds a desktop User-Agent only for requests originating in an EWW
+;; buffer.  These tests pin that scoping: package.el and other non-EWW URL
+;; callers must pass through untouched, so the advice can't change how the
+;; rest of Emacs fetches URLs.
+
+;;; Code:
+
+(require 'ert)
+(require 'cl-lib)
+(require 'eww)
+
+(add-to-list 'load-path (expand-file-name "modules" user-emacs-directory))
+(require 'eww-config)
+
+;;; Normal Cases
+
+(ert-deftest test-eww-ua-injected-in-eww-buffer ()
+  "Normal: in an eww-mode buffer the advice adds the configured User-Agent."
+  (with-temp-buffer
+    (setq major-mode 'eww-mode)
+    (let (seen)
+      (my-eww--inject-user-agent
+       (lambda (&rest _) (setq seen (assoc "User-Agent" url-request-extra-headers))))
+      (should seen)
+      (should (equal (cdr seen) my-eww-user-agent)))))
+
+;;; Boundary Cases
+
+(ert-deftest test-eww-ua-not-injected-outside-eww ()
+  "Boundary: outside eww-mode (package.el, normal url fetches) no UA is added."
+  (with-temp-buffer
+    (fundamental-mode)
+    (let ((url-request-extra-headers nil) captured)
+      (my-eww--inject-user-agent
+       (lambda (&rest _) (setq captured url-request-extra-headers)))
+      (should (null (assoc "User-Agent" captured))))))
+
+(ert-deftest test-eww-ua-replaces-existing-and-keeps-other-headers ()
+  "Boundary: an existing User-Agent is replaced (not duplicated) and other
+headers survive, when the request comes from EWW."
+  (with-temp-buffer
+    (setq major-mode 'eww-mode)
+    (let ((url-request-extra-headers '(("User-Agent" . "old") ("Accept" . "x")))
+          seen)
+      (my-eww--inject-user-agent
+       (lambda (&rest _) (setq seen url-request-extra-headers)))
+      (should (= 1 (cl-count "User-Agent" seen :key #'car :test #'string-equal)))
+      (should (equal (cdr (assoc "User-Agent" seen)) my-eww-user-agent))
+      (should (assoc "Accept" seen)))))
+
+(provide 'test-eww-config-user-agent-advice)
+;;; test-eww-config-user-agent-advice.el ends here