fix: reap completed background jobs before reading status

src/infrastructure/acl/signal-acl.lisp

@@ -115,9 +115,14 @@
     (sb-sys:enable-interrupt sb-unix:sigtstp :default)
     (kill-process (current-process-id) sb-unix:sigtstp)))
 
+(defun %refresh-sbcl-process-statuses ()
+  "Let SBCL update process objects before notifying the shell job monitor."
+  (sb-impl::get-processes-status-changes))
+
 (defun shell-sigchld-handler (signal info context)
-  "Record that child process state changed; reaping is done outside the handler."
+  "Refresh SBCL process objects and record that child state changed."
   (declare (ignore signal info context))
+  (%refresh-sbcl-process-statuses)
   (setf *children-changed* t))
 
 (defun shell-sigwinch-handler (signal info context)

src/presentation/repl-process.lisp

@@ -8,6 +8,10 @@
   #'nshell.infrastructure.acl:process-exit-status-code
   "Function used to read the shell-compatible exit code from a completed background process.")
 
+(defparameter *background-proc-wait*
+  #'nshell.infrastructure.acl:process-wait
+  "Function used to collect a completed background process.")
+
 (defun reap-background-jobs ()
   ;; The registry scan remains authoritative; this only acknowledges signal delivery.
   (nshell.infrastructure.acl:consume-children-changed-p)
@@ -27,6 +31,7 @@
                     jid))
                  (statuses
                    (mapcar (lambda (proc)
+                             (funcall *background-proc-wait* proc)
                              (or (funcall *background-proc-exit-code* proc) 0))
                            procs)))
              (nshell.domain.job-control:complete-job

t/integration/test-signal-handling.lisp

@@ -77,8 +77,13 @@
 
   (it "sigchld-notification-is-consumed-once"
     "Child-process notifications are acknowledged once outside the signal handler."
-    (let ((nshell.infrastructure.acl::*children-changed* nil))
-      (nshell.infrastructure.acl::shell-sigchld-handler nil nil nil)
+    (let ((nshell.infrastructure.acl::*children-changed* nil)
+          (refreshed nil))
+      (with-temporary-function
+          ('nshell.infrastructure.acl::%refresh-sbcl-process-statuses
+           (lambda () (setf refreshed t)))
+        (nshell.infrastructure.acl::shell-sigchld-handler nil nil nil))
+      (expect refreshed :to-be-truthy)
       (expect t :to-be
               (nshell.infrastructure.acl:consume-children-changed-p))
       (expect nil :to-be

t/unit/test-repl-background.lisp

@@ -129,6 +129,9 @@
             (let ((nshell.presentation::*background-proc-alive-p*
                     (lambda (proc)
                       (eq proc alive-proc)))
+                  (nshell.presentation::*background-proc-wait*
+                    (lambda (proc)
+                      (declare (ignore proc))))
                   (nshell.presentation::*background-proc-exit-code*
                     (lambda (proc)
                       (declare (ignore proc))
@@ -168,6 +171,9 @@
             (let ((nshell.presentation::*background-proc-alive-p*
                     (lambda (proc)
                       (eq proc alive-proc)))
+                  (nshell.presentation::*background-proc-wait*
+                    (lambda (proc)
+                      (declare (ignore proc))))
                   (nshell.presentation::*background-proc-exit-code*
                     (lambda (proc)
                       (case proc
@@ -181,6 +187,37 @@
             (expect 23 :to-equal (nshell.domain.execution:job-exit-code completed-job))
             (expect :created :to-be (nshell.domain.execution:job-state alive-job))))))
 
+  (it "reap-background-jobs-waits-before-reading-exit-status"
+    "Reaping should collect each completed process before reading its status."
+    (with-repl-test-state
+        (let* ((monitor (nshell.domain.job-control:make-job-monitor))
+               (job (make-test-job 0 "pipeline"))
+               (proc-1 :proc-1)
+               (proc-2 :proc-2)
+               (job-id (nshell.domain.job-control:monitor-add-job monitor job))
+               (events nil))
+          (let ((nshell.application:*job-monitor* monitor))
+            (repl-test-register-process-entry job-id (list proc-1 proc-2))
+            (let ((nshell.presentation::*background-proc-alive-p*
+                    (lambda (proc)
+                      (declare (ignore proc))
+                      nil))
+                  (nshell.presentation::*background-proc-wait*
+                    (lambda (proc)
+                      (push (list :wait proc) events)))
+                  (nshell.presentation::*background-proc-exit-code*
+                    (lambda (proc)
+                      (push (list :status proc) events)
+                      (if (eq proc proc-1) 11 23))))
+              (nshell.presentation::reap-background-jobs))
+            (expect (list (list :wait proc-1)
+                          (list :status proc-1)
+                          (list :wait proc-2)
+                          (list :status proc-2))
+                    :to-equal
+                    (nreverse events))
+            (expect 23 :to-equal (nshell.domain.execution:job-exit-code job))))))
+
   (it "reap-background-jobs-normalizes-signaled-process-status"
     "Completed background jobs should store shell-compatible signal exit statuses."
     (with-repl-test-state
@@ -218,6 +255,9 @@
                   (lambda (proc)
                     (declare (ignore proc))
                     nil))
+                (nshell.presentation::*background-proc-wait*
+                  (lambda (proc)
+                    (declare (ignore proc))))
                 (nshell.presentation::*background-proc-exit-code*
                   (lambda (proc)
                     (case proc