diff options
| -rw-r--r-- | tests/test-integration-watchdog-signal.el | 151 |
1 files changed, 151 insertions, 0 deletions
diff --git a/tests/test-integration-watchdog-signal.el b/tests/test-integration-watchdog-signal.el new file mode 100644 index 0000000..f786ff9 --- /dev/null +++ b/tests/test-integration-watchdog-signal.el @@ -0,0 +1,151 @@ +;;; test-integration-watchdog-signal.el --- Real-signal watchdog tests -*- 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: + +;; Integration tests for the watchdog against a genuinely stuck child. +;; +;; The unit suite (test-chime-async-watchdog.el, test-chime-async-lifecycle.el) +;; stubs the whole process layer, so the signal semantics the watchdog rests +;; on were unverified anywhere. These tests spawn real processes and let the +;; real kernel deliver the real signals. +;; +;; Components integrated: +;; - chime--kill-async-process (real) +;; - chime--interrupt-stale-process (real) +;; - Emacs process primitives: start-process, delete-process, process-live-p (real) +;; - chime--record-async-failure (MOCKED — the failure machinery has its own tests) +;; +;; Validates: +;; - A child that ignores SIGINT is still killed +;; - The child's process buffer is reaped, which async.el would leak +;; - The watchdog abandons the stuck child and lets the next tick spawn +;; +;; Tagged :slow: each test spawns processes and waits on the kernel. Run +;; with `make test-all'. + +;;; Code: + +(require 'test-bootstrap (expand-file-name "test-bootstrap.el")) + +;;; Helpers + +(defun test-chime-signal--spawn-sigint-immune-child () + "Spawn a real child that traps SIGINT and refuses to die from it. +This is the shape of the bug: a batch Emacs blocked on an interactive +prompt ignores the interrupt and lives on as a zombie." + (let ((process (start-process + "chime-sigint-immune" (generate-new-buffer " *chime-sig*") + "sh" "-c" "trap '' INT; sleep 60"))) + (set-process-query-on-exit-flag process nil) + ;; Give the shell a moment to install the trap. + (sleep-for 0.3) + process)) + +(defun test-chime-signal--wait-for-death (process seconds) + "Wait up to SECONDS for PROCESS to die. Return non-nil if it did." + (let ((deadline (time-add (current-time) (seconds-to-time seconds)))) + (while (and (process-live-p process) + (time-less-p (current-time) deadline)) + (accept-process-output process 0 50)) + (not (process-live-p process)))) + +;;; Integration: the kill path against a real signal-immune child + +(ert-deftest test-integration-watchdog-sigint-immune-child-is-still-killed () + "A child that traps SIGINT survives an interrupt but not `chime--kill-async-process'. +This is the whole reason the watchdog escalates: `interrupt-process' is a +request, and a stuck child is entitled to ignore it." + :tags '(:slow) + (let ((process (test-chime-signal--spawn-sigint-immune-child))) + (unwind-protect + (progn + (should (process-live-p process)) + ;; SIGINT: politely ignored. + (interrupt-process process) + (should-not (test-chime-signal--wait-for-death process 1.5)) + (should (process-live-p process)) + ;; The kill path does not ask. + (chime--kill-async-process process) + (should-not (process-live-p process))) + (when (process-live-p process) (delete-process process))))) + +(ert-deftest test-integration-watchdog-killed-child-leaves-no-buffer () + "The killed child's process buffer is reaped rather than leaked. +async.el kills a child's buffer only on a zero exit, so every signalled +child would otherwise leak one, once per `chime-async-timeout' for as long +as the hang persists." + :tags '(:slow) + (let* ((process (test-chime-signal--spawn-sigint-immune-child)) + (buffer (process-buffer process))) + (unwind-protect + (progn + (should (buffer-live-p buffer)) + (chime--kill-async-process process) + (should-not (process-live-p process)) + (should-not (buffer-live-p buffer))) + (when (process-live-p process) (delete-process process)) + (when (buffer-live-p buffer) (kill-buffer buffer))))) + +(ert-deftest test-integration-watchdog-abandons-a-real-stuck-child () + "The watchdog kills a real over-age child, records the failure, and clears state. +Only `chime--record-async-failure' is mocked; the process, the signal, and +the age check are all real." + :tags '(:slow) + (let* ((process (test-chime-signal--spawn-sigint-immune-child)) + (recorded nil) + (chime-async-timeout 1) + (chime--process process) + (chime--process-generation 0) + ;; Backdate the spawn so the child is over-age immediately. + (chime--process-start-time (time-subtract (current-time) + (seconds-to-time 30)))) + (unwind-protect + (progn + (cl-letf (((symbol-function 'chime--record-async-failure) + (lambda (err prefix) (setq recorded (cons prefix err))))) + (chime--interrupt-stale-process)) + (should-not (process-live-p process)) + (should-not chime--process) + (should-not chime--process-start-time) + ;; The straggler's callback is orphaned. + (should (= chime--process-generation 1)) + (should (equal "Async watchdog" (car recorded)))) + (when (process-live-p process) (delete-process process))))) + +(ert-deftest test-integration-watchdog-leaves-a-young-real-child-alone () + "A child inside its timeout is not killed, even though it is real and stuck." + :tags '(:slow) + (let* ((process (test-chime-signal--spawn-sigint-immune-child)) + (chime-async-timeout 60) + (chime--process process) + (chime--process-generation 0) + (chime--process-start-time (current-time))) + (unwind-protect + (progn + (chime--interrupt-stale-process) + (should (process-live-p process)) + (should (eq chime--process process)) + (should (= chime--process-generation 0))) + (when (process-live-p process) (delete-process process)) + (let ((buffer (process-buffer process))) + (when (buffer-live-p buffer) (kill-buffer buffer)))))) + +(provide 'test-integration-watchdog-signal) +;;; test-integration-watchdog-signal.el ends here |