perf(org-capture): cache file+headline target markers

A task capture took 15-20 seconds: Org resolves a `(file+headline FILE "Headline")' target by opening the file, widening, and regex-scanning from the top for the headline, and the inbox template captures to `(file+headline inbox-file "Inbox")' over and over. An `:around' advice on `org-capture-set-target-location' caches a marker per resolved file/headline. On the next capture it validates the marker (still live, still in an Org buffer, still at a heading, headline text still matches) and jumps straight there. On any mismatch it falls back to the normal scan/create and refreshes the cache. `M-x cj/org-capture-clear-target-cache' resets it. Tests cover the cache hit, marker invalidation after the headline text changes, and creating a missing headline.

1 files changed, 89 insertions, 0 deletions

diff --git a/tests/test-org-capture-config-target-cache.el b/tests/test-org-capture-config-target-cache.el
new file mode 100644
index 00000000..7b88975b
--- /dev/null
+++ b/tests/test-org-capture-config-target-cache.el
@@ -0,0 +1,89 @@
+;;; test-org-capture-config-target-cache.el --- Tests for capture target cache -*- lexical-binding: t; -*-
+
+;;; Commentary:
+;; Tests for cached file+headline org-capture target lookup.
+
+;;; Code:
+
+(require 'ert)
+(require 'cl-lib)
+(require 'org)
+(require 'org-capture)
+
+(add-to-list 'load-path (expand-file-name "modules" user-emacs-directory))
+(require 'org-capture-config)
+
+(defun test-org-capture-target-cache--reset ()
+  "Reset target cache between tests."
+  (clrhash cj/org-capture--file-headline-target-cache))
+
+(defmacro test-org-capture-target-cache--with-temp-org-file (contents &rest body)
+  "Create a temporary Org file with CONTENTS, then run BODY.
+The file-visiting buffer is killed after BODY returns."
+  (declare (indent 1))
+  `(let ((file (make-temp-file "org-capture-target-cache" nil ".org" ,contents)))
+     (unwind-protect
+         (progn ,@body)
+       (when-let ((buffer (find-buffer-visiting file)))
+         (kill-buffer buffer))
+       (when (file-exists-p file)
+         (delete-file file)))))
+
+(ert-deftest test-org-capture-target-cache-second-file-headline-lookup-reuses-marker ()
+  "Normal: repeated file+headline target resolution avoids a second headline scan."
+  (test-org-capture-target-cache--reset)
+  (unwind-protect
+      (test-org-capture-target-cache--with-temp-org-file
+          "* Inbox\n** Existing task\n"
+        (let ((scan-count 0)
+              (original-re-search-forward (symbol-function 're-search-forward)))
+          (cl-letf (((symbol-function 're-search-forward)
+                     (lambda (regexp &optional bound noerror count)
+                       (when (and (stringp regexp)
+                                  (string-match-p "Inbox" regexp))
+                         (cl-incf scan-count))
+                       (funcall original-re-search-forward
+                                regexp bound noerror count))))
+            (let ((org-capture-plist `(:target (file+headline ,file "Inbox"))))
+              (org-capture-set-target-location)
+              (org-capture-set-target-location))
+            (should (= 1 scan-count)))))
+    (test-org-capture-target-cache--reset)))
+
+(ert-deftest test-org-capture-target-cache-validates-marker-headline ()
+  "Boundary: a cached marker is invalid when its heading no longer matches."
+  (test-org-capture-target-cache--reset)
+  (unwind-protect
+      (test-org-capture-target-cache--with-temp-org-file
+          "* Inbox\n"
+        (let ((org-capture-plist `(:target (file+headline ,file "Inbox"))))
+          (org-capture-set-target-location)
+          (let* ((key (cj/org-capture--file-headline-cache-key file "Inbox"))
+                 (marker (gethash key cj/org-capture--file-headline-target-cache)))
+            (should (cj/org-capture--headline-marker-valid-p marker "Inbox"))
+            (with-current-buffer (marker-buffer marker)
+              (save-excursion
+                (goto-char marker)
+                (insert "Renamed ")))
+            (should-not
+             (cj/org-capture--headline-marker-valid-p marker "Inbox")))))
+    (test-org-capture-target-cache--reset)))
+
+(ert-deftest test-org-capture-target-cache-creates-missing-headline-and-caches-it ()
+  "Boundary: missing file+headline targets are created and cached."
+  (test-org-capture-target-cache--reset)
+  (unwind-protect
+      (test-org-capture-target-cache--with-temp-org-file
+          "#+title: Empty\n"
+        (let ((org-capture-plist `(:target (file+headline ,file "Inbox"))))
+          (org-capture-set-target-location)
+          (with-current-buffer (org-capture-get :buffer)
+            (goto-char (org-capture-get :pos))
+            (should (looking-at-p "\\* Inbox")))
+          (let* ((key (cj/org-capture--file-headline-cache-key file "Inbox"))
+                 (marker (gethash key cj/org-capture--file-headline-target-cache)))
+            (should (cj/org-capture--headline-marker-valid-p marker "Inbox")))))
+    (test-org-capture-target-cache--reset)))
+
+(provide 'test-org-capture-config-target-cache)
+;;; test-org-capture-config-target-cache.el ends here