test(org-noter-config): cover preferred-split, slug, template, predicates

Four new test files for the pure-and-near-pure helpers in
org-noter-config.el. The interactive heavyweights (cj/org-noter-start,
cj/org-noter-insert-note-dwim, cj/org-noter--toggle-notes-window,
cj/org-noter--find-notes-file, cj/org-noter--create-notes-file) are
out of scope for this pass — they need org-noter loaded and a real
session, or a substantial internal/wrapper split before they can be
tested without spinning up real PDFs and EPUBs.

- preferred-split: 5 tests walking the 1.4 width-to-height threshold
  from both sides plus a square-frame boundary.
- title-to-slug: 7 tests covering multi-word, single-word, mixed
  punctuation, leading/trailing junk, collapsed runs, digits, and
  empty input.
- generate-notes-template: 5 tests with org-id-uuid mocked, asserting
  the rendered template carries the UUID, the dual ROAM_REFS /
  NOTER_DOCUMENT pointers, the title-and-category lines, the
  ReadingNotes filetag, and the trailing Notes heading.
- predicates: 13 tests covering cj/org-noter--in-document-p,
  cj/org-noter--in-notes-file-p, cj/org-noter--session-active-p,
  cj/org-noter--get-document-path, and cj/org-noter--extract-document-title.
  Mocks derived-mode-p, org-entry-get, and buffer-file-name at the
  boundary so the suite doesn't require pdf-tools or nov.

The require chain in each test file is user-constants → keybindings →
org-noter-config because cj/org-noter-notes-directory captures
roam-dir from user-constants and the prefix-map binding at the bottom
of org-noter-config references cj/custom-keymap.

30 new tests, all passing. Full suite green.

1 files changed, 125 insertions, 0 deletions

diff --git a/tests/test-org-noter-config--predicates.el b/tests/test-org-noter-config--predicates.el
new file mode 100644
index 00000000..09fbe3e8
--- /dev/null
+++ b/tests/test-org-noter-config--predicates.el
@@ -0,0 +1,125 @@
+;;; test-org-noter-config--predicates.el --- Tests for the org-noter-config predicates -*- lexical-binding: t; -*-
+
+;;; Commentary:
+;; Tests for the predicate helpers in org-noter-config.el:
+;; cj/org-noter--in-document-p, cj/org-noter--in-notes-file-p,
+;; cj/org-noter--session-active-p, and cj/org-noter--get-document-path
+;; (mode-dispatch helper).
+;;
+;; Mocks are at the boundary: derived-mode-p for mode dispatch,
+;; org-entry-get for the NOTER_DOCUMENT lookup. The tests don't load
+;; pdf-view or nov; they only need the symbols recognised by
+;; derived-mode-p.
+
+;;; Code:
+
+(require 'ert)
+(require 'cl-lib)
+
+(add-to-list 'load-path (expand-file-name "modules" user-emacs-directory))
+(require 'user-constants)
+(require 'keybindings)
+(require 'org-noter-config)
+
+;; Forward-declare and initialise so cl-letf on symbol-value works.
+(defvar org-noter--session nil)
+(defvar nov-file-name nil)
+
+(defmacro test-org-noter-config--with-mode (mode &rest body)
+  "Run BODY with `derived-mode-p' returning MODE for any matching arg.
+MODE may be a symbol or nil; nil means \"not derived from anything we ask\"."
+  (declare (indent 1) (debug t))
+  `(cl-letf (((symbol-function 'derived-mode-p)
+              (lambda (&rest modes) (and ,mode (memq ,mode modes)))))
+     ,@body))
+
+;;; cj/org-noter--in-document-p
+
+(ert-deftest test-org-noter-config-in-document-p-true-in-pdf-view ()
+  "Normal: pdf-view-mode buffer counts as a document."
+  (test-org-noter-config--with-mode 'pdf-view-mode
+    (should (cj/org-noter--in-document-p))))
+
+(ert-deftest test-org-noter-config-in-document-p-true-in-nov ()
+  "Normal: nov-mode buffer counts as a document."
+  (test-org-noter-config--with-mode 'nov-mode
+    (should (cj/org-noter--in-document-p))))
+
+(ert-deftest test-org-noter-config-in-document-p-false-in-org ()
+  "Boundary: org-mode buffer is not a document."
+  (test-org-noter-config--with-mode 'org-mode
+    (should-not (cj/org-noter--in-document-p))))
+
+(ert-deftest test-org-noter-config-in-document-p-false-in-fundamental ()
+  "Boundary: a fundamental-mode buffer is not a document."
+  (test-org-noter-config--with-mode nil
+    (should-not (cj/org-noter--in-document-p))))
+
+;;; cj/org-noter--in-notes-file-p
+
+(ert-deftest test-org-noter-config-in-notes-file-p-true-when-noter-document-set ()
+  "Normal: org-mode + NOTER_DOCUMENT property → notes file."
+  (test-org-noter-config--with-mode 'org-mode
+    (cl-letf (((symbol-function 'org-entry-get)
+               (lambda (_pos prop)
+                 (when (equal prop "NOTER_DOCUMENT") "/some/doc.pdf"))))
+      (should (cj/org-noter--in-notes-file-p)))))
+
+(ert-deftest test-org-noter-config-in-notes-file-p-false-when-no-property ()
+  "Boundary: org-mode without NOTER_DOCUMENT property → not a notes file."
+  (test-org-noter-config--with-mode 'org-mode
+    (cl-letf (((symbol-function 'org-entry-get) (lambda (&rest _) nil)))
+      (should-not (cj/org-noter--in-notes-file-p)))))
+
+(ert-deftest test-org-noter-config-in-notes-file-p-false-outside-org ()
+  "Boundary: non-org buffers are never notes files even with the property."
+  (test-org-noter-config--with-mode 'pdf-view-mode
+    (cl-letf (((symbol-function 'org-entry-get)
+               (lambda (_pos prop)
+                 (when (equal prop "NOTER_DOCUMENT") "/some/doc.pdf"))))
+      (should-not (cj/org-noter--in-notes-file-p)))))
+
+;;; cj/org-noter--session-active-p
+
+(ert-deftest test-org-noter-config-session-active-p-true-when-session-set ()
+  "Normal: session-active when org-noter--session is non-nil."
+  (cl-letf (((symbol-value 'org-noter--session) 'fake-session))
+    (should (cj/org-noter--session-active-p))))
+
+(ert-deftest test-org-noter-config-session-active-p-false-when-nil ()
+  "Boundary: session-active is nil when org-noter--session is nil."
+  (cl-letf (((symbol-value 'org-noter--session) nil))
+    (should-not (cj/org-noter--session-active-p))))
+
+;;; cj/org-noter--get-document-path
+
+(ert-deftest test-org-noter-config-get-document-path-pdf-uses-buffer-file-name ()
+  "Normal: PDF mode returns `buffer-file-name'."
+  (test-org-noter-config--with-mode 'pdf-view-mode
+    (cl-letf (((symbol-function 'buffer-file-name)
+               (lambda (&optional _) "/books/file.pdf")))
+      (should (equal "/books/file.pdf" (cj/org-noter--get-document-path))))))
+
+(ert-deftest test-org-noter-config-get-document-path-nov-uses-nov-file-name ()
+  "Normal: nov-mode returns `nov-file-name'."
+  (test-org-noter-config--with-mode 'nov-mode
+    (cl-letf (((symbol-value 'nov-file-name) "/books/book.epub"))
+      (should (equal "/books/book.epub" (cj/org-noter--get-document-path))))))
+
+(ert-deftest test-org-noter-config-get-document-path-other-mode-returns-nil ()
+  "Boundary: a non-document mode returns nil."
+  (test-org-noter-config--with-mode 'org-mode
+    (should-not (cj/org-noter--get-document-path))))
+
+;;; cj/org-noter--extract-document-title
+
+(ert-deftest test-org-noter-config-extract-document-title-strips-extension ()
+  "Normal: extract-document-title returns the basename without extension."
+  (test-org-noter-config--with-mode 'pdf-view-mode
+    (cl-letf (((symbol-function 'buffer-file-name)
+               (lambda (&optional _) "/books/the-pragmatic-programmer.pdf")))
+      (should (equal "the-pragmatic-programmer"
+                     (cj/org-noter--extract-document-title))))))
+
+(provide 'test-org-noter-config--predicates)
+;;; test-org-noter-config--predicates.el ends here