test: add unit tests for async result helpers

Eight tests in a new file covering Normal and Boundary cases for both new helpers.

chime--record-async-failure increments the consecutive-failure counter, sets chime-modeline-string to the standard error tooltip, triggers the threshold warning when the counter hits chime-max-consecutive-failures, and leaves chime-modeline-string alone when chime-modeline-no-events-text is nil.

chime--handle-async-success resets the counter from non-zero to zero, invokes the callback with the events list, works with an empty events list, and is a no-op on the counter when it already starts at zero.

1 files changed, 147 insertions, 0 deletions

diff --git a/tests/test-chime-async-helpers.el b/tests/test-chime-async-helpers.el
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+++ b/tests/test-chime-async-helpers.el
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+;;; test-chime-async-helpers.el --- Tests for async result helpers -*- 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.
+
+;; 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 the async-result helpers used inside
+;; chime--fetch-and-process:
+;;   - chime--record-async-failure
+;;   - chime--handle-async-success
+
+;;; Code:
+
+(require 'test-bootstrap (expand-file-name "test-bootstrap.el"))
+
+;;; Setup and Teardown
+
+(defun test-chime-async-helpers-setup ()
+  "Reset counters and modeline state before each test."
+  (setq chime--consecutive-async-failures 0)
+  (setq chime-max-consecutive-failures 5)
+  (setq chime-modeline-no-events-text "*")
+  (setq chime-modeline-string nil))
+
+(defun test-chime-async-helpers-teardown ()
+  "Restore default state after each test."
+  (setq chime--consecutive-async-failures 0)
+  (setq chime-max-consecutive-failures 5)
+  (setq chime-modeline-string nil))
+
+;;;; Tests for chime--record-async-failure
+
+(ert-deftest test-chime-record-async-failure-normal-increments-counter ()
+  "Normal: each call increments the consecutive-failure counter by one."
+  (test-chime-async-helpers-setup)
+  (unwind-protect
+      (let ((err '(error "boom")))
+        (chime--record-async-failure err "Async error")
+        (should (= 1 chime--consecutive-async-failures))
+        (chime--record-async-failure err "Async error")
+        (should (= 2 chime--consecutive-async-failures)))
+    (test-chime-async-helpers-teardown)))
+
+(ert-deftest test-chime-record-async-failure-normal-sets-modeline-error-state ()
+  "Normal: sets chime-modeline-string with the standard error tooltip."
+  (test-chime-async-helpers-setup)
+  (unwind-protect
+      (cl-letf (((symbol-function 'force-mode-line-update) (lambda (&optional _))))
+        (chime--record-async-failure '(error "boom") "Async error")
+        (should chime-modeline-string)
+        (should (string-match-p "Event check failed"
+                                (get-text-property 0 'help-echo chime-modeline-string))))
+    (test-chime-async-helpers-teardown)))
+
+(ert-deftest test-chime-record-async-failure-normal-warns-at-threshold ()
+  "Normal: triggers display-warning when the counter reaches the threshold."
+  (test-chime-async-helpers-setup)
+  (unwind-protect
+      (let ((warned nil))
+        (setq chime--consecutive-async-failures 4)
+        (setq chime-max-consecutive-failures 5)
+        (cl-letf (((symbol-function 'display-warning)
+                   (lambda (_type _msg &rest _args) (setq warned t)))
+                  ((symbol-function 'force-mode-line-update) (lambda (&optional _))))
+          (chime--record-async-failure '(error "boom") "Async error")
+          (should warned)
+          (should (= 5 chime--consecutive-async-failures))))
+    (test-chime-async-helpers-teardown)))
+
+(ert-deftest test-chime-record-async-failure-boundary-no-modeline-text-skips-modeline ()
+  "Boundary: when chime-modeline-no-events-text is nil, modeline string stays nil."
+  (test-chime-async-helpers-setup)
+  (unwind-protect
+      (let ((chime-modeline-no-events-text nil))
+        (setq chime-modeline-string nil)
+        (chime--record-async-failure '(error "boom") "Async error")
+        (should (= 1 chime--consecutive-async-failures))
+        (should (null chime-modeline-string)))
+    (test-chime-async-helpers-teardown)))
+
+;;;; Tests for chime--handle-async-success
+
+(ert-deftest test-chime-handle-async-success-normal-resets-counter ()
+  "Normal: resets the consecutive-failure counter from a positive value to zero."
+  (test-chime-async-helpers-setup)
+  (unwind-protect
+      (let ((called-with nil))
+        (setq chime--consecutive-async-failures 3)
+        (chime--handle-async-success
+         (lambda (events) (setq called-with events))
+         '(event1 event2))
+        (should (= 0 chime--consecutive-async-failures)))
+    (test-chime-async-helpers-teardown)))
+
+(ert-deftest test-chime-handle-async-success-normal-invokes-callback-with-events ()
+  "Normal: calls the supplied callback with the events list."
+  (test-chime-async-helpers-setup)
+  (unwind-protect
+      (let ((called-with 'unset))
+        (chime--handle-async-success
+         (lambda (events) (setq called-with events))
+         '(a b c))
+        (should (equal '(a b c) called-with)))
+    (test-chime-async-helpers-teardown)))
+
+(ert-deftest test-chime-handle-async-success-boundary-empty-events ()
+  "Boundary: works with an empty events list."
+  (test-chime-async-helpers-setup)
+  (unwind-protect
+      (let ((called-with 'unset))
+        (chime--handle-async-success
+         (lambda (events) (setq called-with events))
+         '())
+        (should (null called-with))
+        (should (= 0 chime--consecutive-async-failures)))
+    (test-chime-async-helpers-teardown)))
+
+(ert-deftest test-chime-handle-async-success-boundary-counter-already-zero ()
+  "Boundary: counter starts at zero, stays at zero, callback still fires."
+  (test-chime-async-helpers-setup)
+  (unwind-protect
+      (let ((called-with 'unset))
+        (setq chime--consecutive-async-failures 0)
+        (chime--handle-async-success
+         (lambda (events) (setq called-with events))
+         '(x))
+        (should (= 0 chime--consecutive-async-failures))
+        (should (equal '(x) called-with)))
+    (test-chime-async-helpers-teardown)))
+
+(provide 'test-chime-async-helpers)
+;;; test-chime-async-helpers.el ends here