Add 94 tests across 10 new test files and fix 2 bugs

New test coverage for previously untested functions:
- filter-day-wide-events, time utilities, day-wide time matching
- make-tooltip, event-is-today, get-tags, done-keywords-predicate
- extract-title, propertize-modeline-string, warn-persistent-failures
- log-silently

Bug fixes discovered by new tests:
- Fix pluralization in no-events tooltip ("1 hours" -> "1 hour", etc.)
- Fix chime--get-tags returning ("") instead of nil for untagged headings

1 files changed, 136 insertions, 0 deletions

diff --git a/tests/test-chime-filter-day-wide-events.el b/tests/test-chime-filter-day-wide-events.el
new file mode 100644
index 0000000..885a10d
--- /dev/null
+++ b/tests/test-chime-filter-day-wide-events.el
@@ -0,0 +1,136 @@
+;;; test-chime-filter-day-wide-events.el --- Tests for chime--filter-day-wide-events -*- lexical-binding: t; -*-
+
+;; Copyright (C) 2024-2026 Craig Jennings
+
+;; Author: Craig Jennings <c@cjennings.net>
+
+;; This program is free software: you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+
+;; This program is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+;;; Commentary:
+
+;; Unit tests for chime--filter-day-wide-events function.
+;; This function filters a times alist to keep only entries that have
+;; a time component in their timestamp string (i.e., timed events),
+;; removing all-day events.
+
+;;; Code:
+
+;; Initialize package system for batch mode
+(when noninteractive
+  (package-initialize))
+
+(require 'ert)
+
+;; Load dependencies required by chime
+(require 'dash)
+(require 'alert)
+(require 'async)
+(require 'org-agenda)
+
+;; Load chime from parent directory
+(load (expand-file-name "../chime.el") nil t)
+
+;; Load test utilities
+(require 'testutil-general (expand-file-name "testutil-general.el"))
+(require 'testutil-time (expand-file-name "testutil-time.el"))
+
+;;; Normal Cases
+
+(ert-deftest test-chime-filter-day-wide-events-keeps-timed-event ()
+  "Timed events (with HH:MM) should be kept."
+  (let* ((time (test-time-tomorrow-at 14 30))
+         (ts (test-timestamp-string time))
+         (times (list (cons ts time)))
+         (result (chime--filter-day-wide-events times)))
+    (should (= 1 (length result)))
+    (should (equal (car (car result)) ts))))
+
+(ert-deftest test-chime-filter-day-wide-events-removes-all-day-event ()
+  "All-day events (no HH:MM) should be removed."
+  (let* ((time (test-time-tomorrow-at 0 0))
+         (ts (test-timestamp-string time t)) ;; all-day = t
+         (times (list (cons ts time)))
+         (result (chime--filter-day-wide-events times)))
+    (should (= 0 (length result)))))
+
+(ert-deftest test-chime-filter-day-wide-events-mixed-keeps-only-timed ()
+  "Mixed list should keep only timed events, removing all-day ones."
+  (let* ((timed-time (test-time-tomorrow-at 14 30))
+         (allday-time (test-time-days-from-now 2))
+         (timed-ts (test-timestamp-string timed-time))
+         (allday-ts (test-timestamp-string allday-time t))
+         (times (list (cons timed-ts timed-time)
+                      (cons allday-ts allday-time)))
+         (result (chime--filter-day-wide-events times)))
+    (should (= 1 (length result)))
+    (should (equal (car (car result)) timed-ts))))
+
+(ert-deftest test-chime-filter-day-wide-events-multiple-timed-all-kept ()
+  "Multiple timed events should all be kept."
+  (let* ((time1 (test-time-tomorrow-at 9 0))
+         (time2 (test-time-tomorrow-at 14 30))
+         (time3 (test-time-tomorrow-at 17 0))
+         (times (list (cons (test-timestamp-string time1) time1)
+                      (cons (test-timestamp-string time2) time2)
+                      (cons (test-timestamp-string time3) time3)))
+         (result (chime--filter-day-wide-events times)))
+    (should (= 3 (length result)))))
+
+;;; Boundary Cases
+
+(ert-deftest test-chime-filter-day-wide-events-empty-list ()
+  "Empty times list should return empty list."
+  (should (null (chime--filter-day-wide-events '()))))
+
+(ert-deftest test-chime-filter-day-wide-events-single-timed ()
+  "Single timed event should return list of one."
+  (let* ((time (test-time-tomorrow-at 10 0))
+         (ts (test-timestamp-string time))
+         (result (chime--filter-day-wide-events (list (cons ts time)))))
+    (should (= 1 (length result)))))
+
+(ert-deftest test-chime-filter-day-wide-events-single-all-day ()
+  "Single all-day event should return empty list."
+  (let* ((time (test-time-tomorrow-at 0 0))
+         (ts (test-timestamp-string time t))
+         (result (chime--filter-day-wide-events (list (cons ts time)))))
+    (should (null result))))
+
+(ert-deftest test-chime-filter-day-wide-events-repeating-timed-kept ()
+  "Repeating timestamp with time component should be kept."
+  (let* ((time (test-time-tomorrow-at 9 0))
+         (ts (test-timestamp-repeating time "+1w"))
+         (result (chime--filter-day-wide-events (list (cons ts time)))))
+    (should (= 1 (length result)))))
+
+(ert-deftest test-chime-filter-day-wide-events-repeating-all-day-removed ()
+  "Repeating timestamp without time component should be removed."
+  (let* ((time (test-time-tomorrow-at 0 0))
+         (ts (test-timestamp-repeating time "+1y" t)) ;; all-day repeating
+         (result (chime--filter-day-wide-events (list (cons ts time)))))
+    (should (null result))))
+
+;;; Error Cases
+
+(ert-deftest test-chime-filter-day-wide-events-all-entries-all-day ()
+  "When all entries are all-day, should return empty list."
+  (let* ((time1 (test-time-tomorrow-at 0 0))
+         (time2 (test-time-days-from-now 2))
+         (times (list (cons (test-timestamp-string time1 t) time1)
+                      (cons (test-timestamp-string time2 t) time2)))
+         (result (chime--filter-day-wide-events times)))
+    (should (null result))))
+
+(provide 'test-chime-filter-day-wide-events)
+;;; test-chime-filter-day-wide-events.el ends here