Fix a failing test on Python 3.6

.travis.yml

@@ -1,6 +1,8 @@
 language: python
 python:
+    - '3.4'
     - '3.5'
+    - '3.6'
 sudo: false
 cache: pip
 install:

gns3server/compute/vpcs/vpcs_vm.py

@@ -104,7 +104,7 @@ class VPCSVM(BaseNode):
         Check if VPCS is available with the correct version.
         """
 
-        path = self.vpcs_path
+        path = self._vpcs_path()
         if not path:
             raise VPCSError("No path to a VPCS executable has been set")
 
@@ -146,8 +146,7 @@ class VPCSVM(BaseNode):
         else:
             return None
 
-    @property
+    def _vpcs_path(self):
-    def vpcs_path(self):
         """
         Returns the VPCS executable path.
 
@@ -217,7 +216,7 @@ class VPCSVM(BaseNode):
         Checks if the VPCS executable version is >= 0.8b or == 0.6.1.
         """
         try:
-            output = yield from subprocess_check_output(self.vpcs_path, "-v", cwd=self.working_dir)
+            output = yield from subprocess_check_output(self._vpcs_path(), "-v", cwd=self.working_dir)
             match = re.search("Welcome to Virtual PC Simulator, version ([0-9a-z\.]+)", output)
             if match:
                 version = match.group(1)
@@ -225,7 +224,7 @@ class VPCSVM(BaseNode):
                 if self._vpcs_version < parse_version("0.6.1"):
                     raise VPCSError("VPCS executable version must be >= 0.6.1 but not a 0.8")
             else:
-                raise VPCSError("Could not determine the VPCS version for {}".format(self.vpcs_path))
+                raise VPCSError("Could not determine the VPCS version for {}".format(self._vpcs_path()))
         except (OSError, subprocess.SubprocessError) as e:
             raise VPCSError("Error while looking for the VPCS version: {}".format(e))
 
@@ -270,8 +269,8 @@ class VPCSVM(BaseNode):
                 self.status = "started"
             except (OSError, subprocess.SubprocessError) as e:
                 vpcs_stdout = self.read_vpcs_stdout()
-                log.error("Could not start VPCS {}: {}\n{}".format(self.vpcs_path, e, vpcs_stdout))
+                log.error("Could not start VPCS {}: {}\n{}".format(self._vpcs_path(), e, vpcs_stdout))
-                raise VPCSError("Could not start VPCS {}: {}\n{}".format(self.vpcs_path, e, vpcs_stdout))
+                raise VPCSError("Could not start VPCS {}: {}\n{}".format(self._vpcs_path(), e, vpcs_stdout))
 
     def _termination_callback(self, returncode):
         """
@@ -514,7 +513,7 @@ class VPCSVM(BaseNode):
 
         """
 
-        command = [self.vpcs_path]
+        command = [self._vpcs_path()]
         command.extend(["-p", str(self._internal_console_port)])  # listen to console port
         command.extend(["-m", str(self._manager.get_mac_id(self.id))])   # the unique ID is used to set the MAC address offset
         command.extend(["-i", "1"])  # option to start only one VPC instance

tests/compute/vpcs/test_vpcs_vm.py

@@ -75,7 +75,7 @@ def test_vm_invalid_vpcs_version(loop, manager, vm):
 
 
 def test_vm_invalid_vpcs_path(vm, manager, loop):
-    with asyncio_patch("gns3server.compute.vpcs.vpcs_vm.VPCSVM.vpcs_path", return_value="/tmp/fake/path/vpcs"):
+    with patch("gns3server.compute.vpcs.vpcs_vm.VPCSVM._vpcs_path", return_value="/tmp/fake/path/vpcs"):
         with pytest.raises(VPCSError):
             nio = manager.create_nio({"type": "nio_udp", "lport": 4242, "rport": 4243, "rhost": "127.0.0.1"})
             vm.port_add_nio_binding(0, nio)
@@ -97,7 +97,7 @@ def test_start(loop, vm, async_run):
                     nio = VPCS.instance().create_nio({"type": "nio_udp", "lport": 4242, "rport": 4243, "rhost": "127.0.0.1"})
                     async_run(vm.port_add_nio_binding(0, nio))
                     loop.run_until_complete(asyncio.async(vm.start()))
-                    assert mock_exec.call_args[0] == (vm.vpcs_path,
+                    assert mock_exec.call_args[0] == (vm._vpcs_path(),
                                                       '-p',
                                                       str(vm._internal_console_port),
                                                       '-m', '1',
@@ -133,7 +133,7 @@ def test_start_0_6_1(loop, vm, async_run):
                 nio = VPCS.instance().create_nio({"type": "nio_udp", "lport": 4242, "rport": 4243, "rhost": "127.0.0.1"})
                 async_run(vm.port_add_nio_binding(0, nio))
                 async_run(vm.start())
-                assert mock_exec.call_args[0] == (vm.vpcs_path,
+                assert mock_exec.call_args[0] == (vm._vpcs_path(),
                                                   '-p',
                                                   str(vm._internal_console_port),
                                                   '-m', '1',