Test: fixed osx msg passing issue in testing framework.

The Redis test uses a server-clients model in order to parallelize the
execution of different tests. However in recent versions of osx not
setting the channel to a binary encoding caused issues even if AFAIK no
binary data is really sent via this channel. However now the channels
are deliberately set to a binary encoding and this solves the issue.

The exact issue was the test not terminating and giving the impression
of running forever, since test clients or servers were unable to
exchange the messages to continue.

tests/test_helper.tcl

@@ -204,6 +204,7 @@ proc test_server_main {} {
     # Setup global state for the test server
     set ::idle_clients {}
     set ::active_clients {}
+    array set ::active_clients_task {}
     array set ::clients_start_time {}
     set ::clients_time_history {}
     set ::failed_tests {}
@@ -217,9 +218,12 @@ proc test_server_main {} {
 # may be used in the future in order to detect test clients taking too much
 # time to execute the task.
 proc test_server_cron {} {
+    # Do some work here.
+    after 100 test_server_cron
 }
 
 proc accept_test_clients {fd addr port} {
+    fconfigure $fd -encoding binary
     fileevent $fd readable [list read_from_test_client $fd]
 }
 
@@ -253,14 +257,17 @@ proc read_from_test_client fd {
         puts "\[$completed_tests_count/$all_tests_count [colorstr yellow $status]\]: $data ($elapsed seconds)"
         lappend ::clients_time_history $elapsed $data
         signal_idle_client $fd
+        set ::active_clients_task($fd) DONE
     } elseif {$status eq {ok}} {
         if {!$::quiet} {
             puts "\[[colorstr green $status]\]: $data"
         }
+        set ::active_clients_task($fd) "(OK) $data"
     } elseif {$status eq {err}} {
         set err "\[[colorstr red $status]\]: $data"
         puts $err
         lappend ::failed_tests $err
+        set ::active_clients_task($fd) "(ERR) $data"
     } elseif {$status eq {exception}} {
         puts "\[[colorstr red $status]\]: $data"
         foreach p $::clients_pids {
@@ -268,7 +275,7 @@ proc read_from_test_client fd {
         }
         exit 1
     } elseif {$status eq {testing}} {
-        # No op
+        set ::active_clients_task($fd) "(IN PROGRESS) $data"
     } else {
         if {!$::quiet} {
             puts "\[$status\]: $data"
@@ -282,10 +289,24 @@ proc signal_idle_client fd {
     # Remove this fd from the list of active clients.
     set ::active_clients \
         [lsearch -all -inline -not -exact $::active_clients $fd]
+
+    if 0 {
+        # The following loop is only useful for debugging tests that may
+        # enter an infinite loop. Commented out normally.
+        foreach x $::active_clients {
+            if {[info exist ::active_clients_task($x)]} {
+                puts "$x => $::active_clients_task($x)"
+            } else {
+                puts "$x => ???"
+            }
+        }
+    }
+
     # New unit to process?
     if {$::next_test != [llength $::all_tests]} {
         if {!$::quiet} {
             puts [colorstr bold-white "Testing [lindex $::all_tests $::next_test]"]
+            set ::active_clients_task($fd) "ASSIGNED: $fd ([lindex $::all_tests $::next_test])"
         }
         set ::clients_start_time($fd) [clock seconds]
         send_data_packet $fd run [lindex $::all_tests $::next_test]
@@ -326,6 +347,7 @@ proc the_end {} {
 # to read the command, execute, reply... all this in a loop.
 proc test_client_main server_port {
     set ::test_server_fd [socket localhost $server_port]
+    fconfigure $::test_server_fd -encoding binary
     send_data_packet $::test_server_fd ready [pid]
     while 1 {
         set bytes [gets $::test_server_fd]