curjob in sub-shells?

i was writing some job tests and i noticed this:

  % zsh -fc '( sleep 3 &; disown; jobs ); :'
  zsh:disown:1: no current job
  [2]    running    sleep 3

this is because disown without an argument operates on curjob, and
spawnjob() doesn't update curjob in sub-shells. (for the same reason,
you can't use `kill %%` etc. but `disown %2` or `kill %2` would work)

i tried changing that and it seemed mostly ok, but it caused a test in
W03 to fail. it has this comment:

  # $jobstates refers to a job started in the main shell unless
  # one has been started in the subshell.  In the latter case,
  # the subshell has no job control so the job is not marked as current.

i don't understand. what would be the negative consequences of marking
the job as current in a sub-shell?

fwiw: dash, bash, and ksh93 all show the job as current. disown and
`kill %%` work as expected in bash, with or without monitor. `kill %%`
works in ksh93; i'm not sure if disown does because ksh93 disown doesn't
actually remove jobs from the job table. neither works in dash

below is the change i made

dana


diff --git a/Src/jobs.c b/Src/jobs.c
index 2ce5f8254..10ce965a3 100644
--- a/Src/jobs.c
+++ b/Src/jobs.c
@@ -1896,21 +1896,19 @@ spawnjob(void)
     Process pn;
 
     DPUTS(thisjob == -1, "No valid job in spawnjob.");
-    /* if we are not in a subshell */
-    if (!subsh) {
-	if (curjob == -1 || !(jobtab[curjob].stat & STAT_STOPPED)) {
-	    curjob = thisjob;
-	    setprevjob();
-	} else if (prevjob == -1 || !(jobtab[prevjob].stat & STAT_STOPPED))
-	    prevjob = thisjob;
-	if (jobbing && jobtab[thisjob].procs) {
-	    FILE *fout = shout ? shout : stdout;
-	    fprintf(fout, "[%d]", thisjob);
-	    for (pn = jobtab[thisjob].procs; pn; pn = pn->next)
-		fprintf(fout, " %ld", (long) pn->pid);
-	    fprintf(fout, "\n");
-	    fflush(fout);
-	}
+    if (curjob == -1 || !(jobtab[curjob].stat & STAT_STOPPED)) {
+	curjob = thisjob;
+	setprevjob();
+    } else if (prevjob == -1 || !(jobtab[prevjob].stat & STAT_STOPPED))
+	prevjob = thisjob;
+
+    if (!subsh && jobbing && jobtab[thisjob].procs) {
+	FILE *fout = shout ? shout : stdout;
+	fprintf(fout, "[%d]", thisjob);
+	for (pn = jobtab[thisjob].procs; pn; pn = pn->next)
+	    fprintf(fout, " %ld", (long) pn->pid);
+	fprintf(fout, "\n");
+	fflush(fout);
     }
     if (!hasprocs(thisjob))
 	deletejob(jobtab + thisjob, 0);