2 files changed, 42 insertions, 0 deletions

diff --git a/test/src/callproc-tests.el b/test/src/callproc-tests.el
index 7b30a251cce..f351b6e2148 100644
--- a/test/src/callproc-tests.el
+++ b/test/src/callproc-tests.el
@@ -37,3 +37,25 @@
         (split-string-and-unquote (buffer-string)))
     (should (equal initial-shell "nil"))
     (should-not (equal initial-shell shell))))
+
+(ert-deftest call-process-w32-debug-spawn-error ()
+  "Check that debugger runs on `call-process' failure (Bug#33016)."
+  (skip-unless (eq system-type 'windows-nt))
+  (let* ((debug-on-error t)
+         (have-called-debugger nil)
+         (debugger (lambda (&rest _)
+                     (setq have-called-debugger t)
+                     ;; Allow entering the debugger later in the same
+                     ;; test run, before going back to the command
+                     ;; loop.
+                     (setq internal-when-entered-debugger -1))))
+    (should (eq :got-error ;; NOTE: `should-error' would inhibit debugger.
+                (condition-case-unless-debug ()
+                    ;; On Windows, "nul.FOO" act like an always-empty
+                    ;; file for any FOO, in any directory.  So this
+                    ;; passes Emacs' test for the file's existence,
+                    ;; and ensures we hit an error in the w32 process
+                    ;; spawn code.
+                    (call-process "c:/nul.exe")
+                  (error :got-error))))
+    (should have-called-debugger)))
diff --git a/test/src/process-tests.el b/test/src/process-tests.el
index 5dbf441e8c2..0bb7ebe50a8 100644
--- a/test/src/process-tests.el
+++ b/test/src/process-tests.el
@@ -215,6 +215,26 @@
                                       (string-to-list "stdout\n")
                                       (string-to-list "stderr\n"))))))
 
+(ert-deftest make-process-w32-debug-spawn-error ()
+  "Check that debugger runs on `make-process' failure (Bug#33016)."
+  (skip-unless (eq system-type 'windows-nt))
+  (let* ((debug-on-error t)
+         (have-called-debugger nil)
+         (debugger (lambda (&rest _)
+                     (setq have-called-debugger t)
+                     ;; Allow entering the debugger later in the same
+                     ;; test run, before going back to the command
+                     ;; loop.
+                     (setq internal-when-entered-debugger -1))))
+    (should (eq :got-error ;; NOTE: `should-error' would inhibit debugger.
+                (condition-case-unless-debug ()
+                    ;; Emacs doesn't search for absolute filenames, so
+                    ;; the error will be hit in the w32 process spawn
+                    ;; code.
+                    (make-process :name "test" :command '("c:/No-Such-Command"))
+                  (error :got-error))))
+    (should have-called-debugger)))
+
 (ert-deftest make-process/file-handler/found ()
   "Check that the ‘:file-handler’ argument of ‘make-process’
 works as expected if a file name handler is found."