test: support both Python 2 & 3 in the test runner

Python 2 going to its real EOL and it is often easier to get Python 3 on
a certain system rather than Python 2.

The test runner layer, which is written in Python is quite thin, so it
worth re-write it to support both Python 2 and Python 3.

lib/tarantool_server.py

@@ -95,17 +95,17 @@ def execute_no_reconnect(self, command):
         if not command:
             return
         cmd = command.replace('\n', ' ') + '\n'
-        self.socket.sendall(cmd)
+        self.socket.sendall(cmd.encode())
 
         bufsiz = 4096
-        res = ""
+        res = b""
 
         while True:
             buf = self.socket.recv(bufsiz)
             if not buf:
                 break
             res = res + buf
-            if (res.rfind("\n...\n") >= 0 or res.rfind("\r\n...\r\n") >= 0):
+            if (res.rfind(b"\n...\n") >= 0 or res.rfind(b"\r\n...\r\n") >= 0):
                 break
 
         return yaml.safe_load(res)
@@ -245,7 +245,7 @@ def start(self):
         self.generate_configuration()
         if self.script:
             shutil.copy(self.script, self.script_dst)
-            os.chmod(self.script_dst, 0777)
+            os.chmod(self.script_dst, 0o777)
         args = self.prepare_args()
         self.process = subprocess.Popen(args,
                 cwd = self.vardir,

test-run.py

@@ -1,4 +1,4 @@
-#!/usr/bin/env python2.7
+#!/usr/bin/env python
 
 import os
 import sys
@@ -15,7 +15,7 @@
 def read_popen(cmd):
     path = subprocess.Popen(cmd, shell=True, stdout=subprocess.PIPE)
     path.wait()
-    return path.stdout.read()
+    return path.stdout.read().decode()
 
 def read_popen_config(cmd):
     cmd = os.environ.get('PHP_CONFIG', 'php-config') + ' ' + cmd
@@ -111,9 +111,9 @@ def main():
                 cmd = cmd + 'sudo dtruss ' + find_php_bin()
                 cmd = cmd + ' -c tarantool.ini {0}'.format(test_lib_path)
             else:
-                print find_php_bin()
+                print(find_php_bin())
                 cmd = '{0} -c tarantool.ini {1}'.format(find_php_bin(), test_lib_path)
-                print cmd
+                print(cmd)
 
             print('Running "%s" with "%s"' % (cmd, php_ini))
             proc = subprocess.Popen(cmd, shell=True, cwd=test_cwd)