fix the blocking behavior when tmpdir disappears when the server is stopping

cpanfile

@@ -5,10 +5,10 @@ requires 'Time::HiRes';
 on configure => sub {
     requires 'Module::Build::Tiny', '0.035';
     requires 'perl', '5.008_001';
+    requires 'Redis';
 };
 
 on test => sub {
-    requires 'Redis';
     requires 'Test::More', '0.98';
     requires 'Test::TCP';
 };

lib/Test/RedisServer.pm

@@ -10,6 +10,7 @@ use File::Temp;
 use POSIX qw(SIGTERM WNOHANG);
 use Time::HiRes qw(sleep);
 use Errno ();
+use Redis;
 
 has auto_start => (
     is      => 'rw',
@@ -36,6 +37,11 @@ has tmpdir  => (
     lazy_build => 1,
 );
 
+has _redis => (
+    is  => 'rw',
+    isa => 'Redis',
+);
+
 no Mouse;
 
 sub BUILD {
@@ -133,6 +139,13 @@ sub start {
         };
     }
 
+    # This is sometimes needed to send commands to RedisServer during the stop process.
+    # Generally, we would like to generate it lazily and not have it as a property
+    # of the object. However, if you try to create the object at the stop,
+    # the object generation may fail, such as missing the socket file. Therefore,
+    # we will make the object and store it as property here.
+    $self->_redis( Redis->new($self->connect_info) );
+
     $self->pid($pid);
 }
 
@@ -163,6 +176,18 @@ sub stop {
     local $?; # waitpid may change this value :/
     return unless defined $self->pid;
 
+    # If the tmpdir has disappeared, clear the save config to prevent saving
+    # in the server terminating process. The newer Redis will save on stop
+    # for robustness, but will keep blocking if the directory is missing.
+    #
+    # It is unlikely that tmpdir will disappear first, but if both the RedisServer
+    # object and the tmpdir are defined globally, it may happen because the order
+    # in which they are DESTLOYed is uncertain.
+    if (! -f $self->tmpdir) {
+        $self->_redis->config_set('appendonly', 'no');
+        $self->_redis->config_set('save', '');
+    }
+
     $sig ||= SIGTERM;
 
     kill $sig, $self->pid;

t/no_save.t

@@ -0,0 +1,20 @@
+use strict;
+use warnings;
+use Test::More;
+use File::Path 'remove_tree';
+
+use Test::RedisServer;
+
+eval { Test::RedisServer->new } or plan skip_all => 'redis-server is required in PATH to run this test';
+
+my $tmpdir = File::Temp->newdir;
+my $server = Test::RedisServer->new(tmpdir => $tmpdir);
+ok $server->pid, 'pid ok';
+
+remove_tree($tmpdir);
+ok ! -f $tmpdir;
+
+$server->stop;
+pass 'redis exit ok';
+
+done_testing;