[PATCH 3/4] tests: note kevent+tmpfs failures on DragonFly <= 6.4

[Eric Wong <e@80x24.org>]

I forgot to set TMPDIR=/path/to/non-tmpfs again.
---
 lib/PublicInbox/TestCommon.pm | 23 ++++++++++++++++++++++-
 t/dir_idle.t                  |  7 +++++--
 t/kqnotify.t                  |  2 +-
 3 files changed, 28 insertions(+), 4 deletions(-)

diff --git a/lib/PublicInbox/TestCommon.pm b/lib/PublicInbox/TestCommon.pm
index 8e7eb950..f2914d09 100644
--- a/lib/PublicInbox/TestCommon.pm
+++ b/lib/PublicInbox/TestCommon.pm
@@ -24,7 +24,7 @@ BEGIN {
 	@EXPORT = qw(tmpdir tcp_server tcp_connect require_git require_mods
 		run_script start_script key2sub xsys xsys_e xqx eml_load tick
 		have_xapian_compact json_utf8 setup_public_inboxes create_inbox
-		create_coderepo require_bsd
+		create_coderepo require_bsd kernel_version check_broken_tmpfs
 		quit_waiter_pipe wait_for_eof
 		tcp_host_port test_lei lei lei_ok $lei_out $lei_err $lei_opt
 		test_httpd xbail require_cmd is_xdeeply tail_f
@@ -37,6 +37,27 @@ BEGIN {
 	push @EXPORT, @methods;
 }
 
+sub kernel_version () {
+	state $version = do {
+		require POSIX;
+		my @u = POSIX::uname();
+		if ($u[2] =~ /\A([0-9]+(?:\.[0-9]+)+)/) {
+			eval "v$1";
+		} else {
+			local $" = "', `";
+			diag "Unable to get kernel version from: `@u'";
+			undef;
+		}
+	};
+}
+
+sub check_broken_tmpfs () {
+	return if $^O ne 'dragonfly' || kernel_version ge v6.5;
+	diag 'EVFILT_VNODE + tmpfs is broken on dragonfly <= 6.4 (have: '.
+		sprintf('%vd', kernel_version).')';
+	1;
+}
+
 sub require_bsd (;$) {
 	state $ok = ($^O =~ m!\A(?:free|net|open)bsd\z! ||
 			$^O eq 'dragonfly');
diff --git a/t/dir_idle.t b/t/dir_idle.t
index 14aad7a1..8d085d6e 100644
--- a/t/dir_idle.t
+++ b/t/dir_idle.t
@@ -16,10 +16,12 @@ my $end = 3 + now;
 local @PublicInbox::DS::post_loop_do = (sub { scalar(@x) == 0 && now < $end });
 rmdir("$tmpdir/a/b") or xbail "rmdir $!";
 PublicInbox::DS::event_loop();
-is(scalar(@x), 1, 'got an rmdir event') or xbail explain(\@x);
-if (@x) {
+if (is(scalar(@x), 1, 'got an rmdir event')) {
 	is($x[0]->[0]->fullname, "$tmpdir/a/b", 'got expected fullname') and
 	ok($x[0]->[0]->IN_DELETE, 'IN_DELETE set');
+} else {
+	check_broken_tmpfs;
+	xbail explain(\@x);
 }
 
 rmdir("$tmpdir/a") or xbail "rmdir $!";
@@ -30,6 +32,7 @@ if (is(scalar(@x), 1, 'got an event after rmdir')) {
 	is($x[0]->[0]->fullname, "$tmpdir/a", 'got expected fullname') and
 	ok($x[0]->[0]->IN_DELETE_SELF, 'IN_DELETE_SELF set');
 } else {
+	check_broken_tmpfs;
 	diag explain(\@x);
 }
 rename("$tmpdir/c", "$tmpdir/j") or xbail "rmdir $!";
diff --git a/t/kqnotify.t b/t/kqnotify.t
index cf32b633..add477a4 100644
--- a/t/kqnotify.t
+++ b/t/kqnotify.t
@@ -62,6 +62,6 @@ is_xdeeply($hit, \@unlink, 'unlinked files match');
 # this is unreliable on Dragonfly tmpfs (fixed post-6.4)
 rmdir "$tmpdir/new";
 $hit = [ sort(map { $_->fullname } $kqn->read) ];
-is(scalar(@$hit), 1, 'detected self removal');
+is(scalar(@$hit), 1, 'detected self removal') or check_broken_tmpfs;
 
 done_testing;