refactor(epub): clean up calibredb-epub-config.el

Dropped the 1-second `:defer' from the calibredb use-package and the redundant explicit `nov-render-document' call in `cj/nov-apply-preferences'. Nov / visual-fill-column text width now recalculates on `window-configuration-change-hook'. `cj/nov--text-width-for-window' computes the (clamped, minimum-readable) width and `cj/nov-update-layout' installs it buffer-locally. Lowered `calibredb-search-page-max-rows' from 20000 to 500 (pagination was effectively disabled). Replaced the anonymous zathura keybinding with `cj/nov-open-external'. Tests cover the width computation and the external-open binding.

1 files changed, 52 insertions, 0 deletions

diff --git a/tests/test-calibredb-epub-config.el b/tests/test-calibredb-epub-config.el
new file mode 100644
index 00000000..5b578b7d
--- /dev/null
+++ b/tests/test-calibredb-epub-config.el
@@ -0,0 +1,52 @@
+;;; test-calibredb-epub-config.el --- Tests for ebook config helpers -*- lexical-binding: t; -*-
+
+;;; Commentary:
+;; Focuses on project-owned helpers in calibredb-epub-config rather than
+;; CalibreDB/Nov internals.
+
+;;; Code:
+
+(require 'ert)
+(require 'cl-lib)
+
+(add-to-list 'load-path (expand-file-name "modules" user-emacs-directory))
+(require 'calibredb-epub-config)
+
+(ert-deftest test-calibredb-epub-nov-text-width-default-window ()
+  "Normal: text width uses the configured margins against the current window."
+  (let ((cj/nov-margin-percent 25)
+        (cj/nov-min-text-width 40))
+    (cl-letf (((symbol-function 'get-buffer-window)
+               (lambda (&rest _) 'window))
+              ((symbol-function 'window-body-width)
+               (lambda (_) 120)))
+      (should (= 60 (cj/nov--text-width-for-window))))))
+
+(ert-deftest test-calibredb-epub-nov-text-width-clamps-large-margin ()
+  "Boundary: excessive margins are clamped to keep a readable text column."
+  (let ((cj/nov-margin-percent 80)
+        (cj/nov-min-text-width 40))
+    (cl-letf (((symbol-function 'get-buffer-window)
+               (lambda (&rest _) 'window))
+              ((symbol-function 'window-body-width)
+               (lambda (_) 120)))
+      (should (= 40 (cj/nov--text-width-for-window))))))
+
+(ert-deftest test-calibredb-epub-nov-text-width-fallback-without-window ()
+  "Boundary: a buffer without a visible window still gets a usable width."
+  (let ((cj/nov-margin-percent 25)
+        (cj/nov-min-text-width 40))
+    (cl-letf (((symbol-function 'get-buffer-window)
+               (lambda (&rest _) nil)))
+      (should (= 40 (cj/nov--text-width-for-window))))))
+
+(ert-deftest test-calibredb-epub-open-external-uses-zathura ()
+  "Normal: named Nov external-open command delegates to zathura."
+  (let (command)
+    (cl-letf (((symbol-function 'cj/open-file-with-command)
+               (lambda (cmd) (setq command cmd))))
+      (cj/nov-open-external)
+      (should (equal command "zathura")))))
+
+(provide 'test-calibredb-epub-config)
+;;; test-calibredb-epub-config.el ends here