test: close coverage gaps to 99.88% line coverage

Five new test files cover branches the per-function suites missed: the day-wide notification pipeline, the jump-to-event navigation path (including the org-show-entry fallback for Org < 9.6), chime--stop's process-interrupt branch, chime--start's debug log, and the two async error branches in chime--fetch-and-process. The edge-coverage file mops up scattered one-line fallbacks: the day-wide-notification "today" path, the tooltip placeholder pass-through, timestamp-parse's no-context error message, log-silently's mid-line newline insert, the validation :error count, and record-async-failure's chime-debug hook.

Line coverage on chime.el goes from 97.1% to 99.88%, 823 of 824 coverable lines. The one remaining line is a pcase _ fallback the preceding regex can't reach.

1 files changed, 87 insertions, 0 deletions

diff --git a/tests/test-chime-lifecycle.el b/tests/test-chime-lifecycle.el
new file mode 100644
index 0000000..8ce9c13
--- /dev/null
+++ b/tests/test-chime-lifecycle.el
@@ -0,0 +1,87 @@
+;;; test-chime-lifecycle.el --- Tests for chime--stop and chime--start -*- lexical-binding: t; -*-
+
+;; Copyright (C) 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.
+
+;;; Commentary:
+
+;; Unit tests for the internal lifecycle entry points `chime--stop' and
+;; `chime--start'.  Tests cover branches not exercised by higher-level
+;; mode-toggle tests: in-progress process cleanup and the debug-only
+;; scheduling log line.
+
+;;; Code:
+
+(require 'test-bootstrap (expand-file-name "test-bootstrap.el"))
+(require 'cl-lib)
+
+(ert-deftest test-chime-stop-interrupts-running-process ()
+  "Normal: when chime--process is set, `chime--stop' interrupts it and clears the var."
+  (let ((interrupted nil)
+        (chime--timer nil)
+        (chime--process 'fake-process)
+        (chime--validation-done t)
+        (chime--validation-retry-count 5))
+    (cl-letf (((symbol-function 'interrupt-process)
+               (lambda (proc) (setq interrupted proc))))
+      (chime--stop))
+    (should (eq 'fake-process interrupted))
+    (should (null chime--process))
+    (should-not chime--validation-done)
+    (should (= 0 chime--validation-retry-count))))
+
+(ert-deftest test-chime-stop-no-process-skips-interrupt ()
+  "Boundary: with chime--process nil, `interrupt-process' is never called."
+  (let ((interrupted nil)
+        (chime--timer nil)
+        (chime--process nil)
+        (chime--validation-done t)
+        (chime--validation-retry-count 5))
+    (cl-letf (((symbol-function 'interrupt-process)
+               (lambda (proc) (setq interrupted proc))))
+      (chime--stop))
+    (should (null interrupted))
+    (should-not chime--validation-done)
+    (should (= 0 chime--validation-retry-count))))
+
+(ert-deftest test-chime-start-logs-debug-message-when-feature-loaded ()
+  "Normal: with the chime-debug feature loaded, start emits a scheduling log line."
+  (let ((logged nil)
+        (chime--timer nil)
+        (chime--process nil))
+    (cl-letf (((symbol-function 'featurep)
+               (lambda (feat &rest _) (eq feat 'chime-debug)))
+              ((symbol-function 'run-at-time)
+               (lambda (&rest _) 'fake-timer))
+              ((symbol-function 'chime--log-silently)
+               (lambda (fmt &rest args)
+                 (push (apply #'format fmt args) logged))))
+      (chime--start))
+    (should (cl-some (lambda (m) (string-match-p "Scheduling first check" m))
+                     logged))
+    (should (eq 'fake-timer chime--timer))))
+
+(ert-deftest test-chime-start-skips-debug-log-when-feature-absent ()
+  "Boundary: without the chime-debug feature loaded, no log line is emitted."
+  (let ((logged nil)
+        (chime--timer nil)
+        (chime--process nil))
+    (cl-letf (((symbol-function 'featurep)
+               (lambda (feat &rest _) (not (eq feat 'chime-debug))))
+              ((symbol-function 'run-at-time)
+               (lambda (&rest _) 'fake-timer))
+              ((symbol-function 'chime--log-silently)
+               (lambda (fmt &rest args)
+                 (push (apply #'format fmt args) logged))))
+      (chime--start))
+    (should (null logged))
+    (should (eq 'fake-timer chime--timer))))
+
+(provide 'test-chime-lifecycle)
+;;; test-chime-lifecycle.el ends here