diff --git a/tests/conftest.py b/tests/conftest.py
new file mode 100644
index 0000000..11a887b
--- /dev/null
+++ b/tests/conftest.py
@@ -0,0 +1,76 @@
+# -*- coding: utf-8 -*-
+
+import pysphere
+
+
+def pytest_sessionstart(session):
+
+    class VMInstanceWrapper(object):
+
+        def __init__(self, status='POWERED OFF'):
+            self.status = status
+
+        def get_status(self, *args, **kwargs):
+            return self.status
+
+        def power_on(self, *args, **kwargs):
+            return 'TEST POWER ON'
+
+        def power_off(self, *args, **kwargs):
+            return 'TEST POWER OFF'
+
+        def wait_for_tools(self, *args, **kwargs):
+            return 'Waiting until OS started...'
+
+        def get_properties(self, *args, **kwargs):
+            return {'ip_address': '0.0.0.0', 'test': 123, 'testSub': {'subName': {'subSubName': 'qqq'}}}
+
+        def get_current_snapshot_name(self, *args, **kwargs):
+            return ''
+
+        def get_snapshots(self, *args, **kwargs):
+            return ['current snapshot', 'another snapshot']
+
+        def revert_to_snapshot(self, *args, **kwargs):
+            return 'reverting to current snapshot...'
+
+        def revert_to_named_snapshot(self, *args, **kwargs):
+            return 'reverting to named snapshot...'
+
+        def delete_named_snapshot(self, *args, **kwargs):
+            return 'deleting named snapshot...'
+
+        def create_snapshot(self, *args, **kwargs):
+            return 'creating new snapshot...'
+
+        def clone(self, *args, **kwargs):
+            return 'cloning vm...'
+
+        def login_in_guest(self, *args, **kwargs):
+            return 'login in guest'
+
+        def send_file(self, *args, **kwargs):
+            return 'sending file...'
+
+        def get_file(self, *args, **kwargs):
+            return 'geting file...'
+
+        def make_directory(self, *args, **kwargs):
+            return 'making directory...'
+
+    class VIServerWrapper(object):
+
+        def connect(self, *args, **kwargs):
+            return 'CONNECTED'
+
+        def get_vm_by_name(self, *args, **kwargs):
+            if 'FAKE' in args:
+                raise Exception('No Name found for CloneVM test')
+
+            else:
+                return VMInstanceWrapper()
+
+        def delete_vm_by_name(self, *args, **kwargs):
+            return True, 'DELETED'
+
+    pysphere.VIServer = VIServerWrapper
diff --git a/tests/test_vspheretools.py b/tests/test_vspheretools.py
index 336a45d..8862652 100644
--- a/tests/test_vspheretools.py
+++ b/tests/test_vspheretools.py
@@ -9,8 +9,139 @@ class TestVSphereTools():
     @pytest.fixture(scope='class', autouse=True)
     def init(self):
         VSphereTools.LOGGER.setLevel(50)  # Disable debug logging while test
-        # sphere = VSphereTools.Sphere()
 
     def test_Version(self):
         assert isinstance(VSphereTools.Version(True), str), 'Input: [ True ] expected output: [ isinstance(True, str) == True]'
         assert isinstance(VSphereTools.Version(False), str), 'Input: [ False ] expected output: [ isinstance(False, str) == True]'
+
+    def test_Constants(self):
+        assert VSphereTools.VC_SERVER == ""  # empty is default
+        assert VSphereTools.VC_LOGIN == ""  # empty is default
+        assert VSphereTools.VC_PASSWORD == ""  # empty is default
+        assert VSphereTools.VM_NAME == ""  # empty is default
+        assert VSphereTools.VM_GUEST_LOGIN == ""  # empty is default
+        assert VSphereTools.VM_GUEST_PASSWORD == ""  # empty is default
+        assert VSphereTools.VM_CLONES_DIR == "Clones"  # "Clones" is default
+        assert VSphereTools.OP_TIMEOUT == 300  # 300 is default
+
+    def test_init(self):
+        sphere = VSphereTools.Sphere()
+        assert sphere.vSphereServerInstance.connect() == 'CONNECTED'
+        assert isinstance(sphere, VSphereTools.Sphere)
+
+    def test_VMStatus(self):
+        sphere = VSphereTools.Sphere()
+        assert sphere.VMStatus() == 'POWERED OFF'
+
+    def test_VMStart(self):
+        sphere = VSphereTools.Sphere()
+        assert sphere.VMStart() == 'POWERED OFF'
+
+    def test_VMStartWait(self):
+        sphere = VSphereTools.Sphere()
+        assert sphere.VMStart() == 'POWERED OFF'
+
+    def test_VMStop(self):
+        sphere = VSphereTools.Sphere()
+        # TODO: How to check this method if status == 'POWERED ON'
+        assert sphere.VMStop() == 'POWERED OFF'
+
+    def test_GetVMProperties(self):
+        sphere = VSphereTools.Sphere()
+        assert sphere.GetVMProperties() == {'ip_address': '0.0.0.0', 'test': 123, 'testSub': {'subName': {'subSubName': 'qqq'}}}
+
+    def test_GetVMSnapshotsList(self):
+        sphere = VSphereTools.Sphere()
+        assert isinstance(sphere.GetVMSnapshotsList(), list)
+        assert sphere.GetVMSnapshotsList() == ['current snapshot', 'another snapshot']
+
+    def test_CreateVMSnapshot(self):
+        sphere = VSphereTools.Sphere()
+        # TODO: check statusCode == 0 and statusCode == 2. How to prevent snap.get_name() call?
+        assert sphere.CreateVMSnapshot(name=None) == 1  # Fail because snapshot name not define
+        assert sphere.CreateVMSnapshot(name='FAKE') == -1  # Fail because an error occured while creating snapshots
+
+    def test_GetVMIPaddress(self):
+        sphere = VSphereTools.Sphere()
+        assert sphere.GetVMIPaddress() == '0.0.0.0'
+
+    def test_SetVMIPaddressIntoTeamCityParameter(self):
+        sphere = VSphereTools.Sphere()
+        assert sphere.SetVMIPaddressIntoTeamCityParameter(paramName=None) is None  # return None by default
+
+    def test_VMRevertToCurrentSnapshot(self):
+        sphere = VSphereTools.Sphere()
+        assert sphere.VMRevertToCurrentSnapshot() == 0  # Success operation
+
+    def test_VMRevertToSnapshot(self):
+        sphere = VSphereTools.Sphere()
+        # TODO: How to raise exception for check statusCode == -2
+        assert sphere.VMRevertToSnapshot(snapshotName=None) == 0  # Success operation if current snapshot
+        assert sphere.VMRevertToSnapshot(snapshotName='FAKE') == 0  # Success operation if named snapshot
+
+    def test_CloneVM(self):
+        sphere = VSphereTools.Sphere()
+        # TODO: How to check with 'POWERED ON' status?
+        assert sphere.CloneVM(cloneName='FAKE') is None  # return None by default
+
+    def test_DeleteVM(self):
+        sphere = VSphereTools.Sphere()
+        assert sphere.DeleteVM() is None  # Success delete operation return None by default
+
+    def test_CopyFileIntoVM(self):
+        sphere = VSphereTools.Sphere()
+        # TODO: How to check this method if status == 'POWERED ON'?
+        with pytest.raises(Exception):
+            sphere.CopyFileIntoVM(srcFile=None, dstFile=None, overwrite=False)
+        with pytest.raises(Exception):
+            sphere.CopyFileIntoVM(srcFile=None, dstFile=None, overwrite=True)
+        with pytest.raises(Exception):
+            sphere.CopyFileIntoVM(srcFile='SOMEPATH', dstFile='SOMEPATH', overwrite=False)
+        with pytest.raises(Exception):
+            sphere.CopyFileIntoVM(srcFile='SOMEPATH', dstFile='SOMEPATH', overwrite=True)
+
+    def test_CopyFileFromVM(self):
+        sphere = VSphereTools.Sphere()
+        # TODO: How to check this method if status == 'POWERED ON'?
+        with pytest.raises(Exception):
+            sphere.CopyFileFromVM(srcFile=None, dstFile=None, overwrite=False)
+        with pytest.raises(Exception):
+            sphere.CopyFileFromVM(srcFile=None, dstFile=None, overwrite=True)
+        with pytest.raises(Exception):
+            sphere.CopyFileFromVM(srcFile='SOMEPATH', dstFile='SOMEPATH', overwrite=False)
+        with pytest.raises(Exception):
+            sphere.CopyFileFromVM(srcFile='SOMEPATH', dstFile='SOMEPATH', overwrite=True)
+
+    def test_MakeDirectoryOnVM(self):
+        sphere = VSphereTools.Sphere()
+        # TODO: How to check this method if status == 'POWERED ON'?
+        with pytest.raises(Exception):
+            sphere.MakeDirectoryOnVM(dirPath=None, createSubDirs=True)
+        with pytest.raises(Exception):
+            sphere.MakeDirectoryOnVM(dirPath=None, createSubDirs=False)
+        with pytest.raises(Exception):
+            sphere.MakeDirectoryOnVM(dirPath='SOMEDIR', createSubDirs=True)
+        with pytest.raises(Exception):
+            sphere.MakeDirectoryOnVM(dirPath='SOMEDIR', createSubDirs=True)
+
+    def test_MonitoringProcessOnVM(self):
+        sphere = VSphereTools.Sphere()
+        assert sphere.MonitoringProcessOnVM(pID=None, remoteLogFile=None) == -1  # -1 because state is 'POWERED OFF'
+        assert sphere.MonitoringProcessOnVM(pID=None, remoteLogFile='SOMEFILE') == -1
+        assert sphere.MonitoringProcessOnVM(pID=123, remoteLogFile=None) == -1
+        assert sphere.MonitoringProcessOnVM(pID=123, remoteLogFile='SOMEFILE') == -1
+
+    def test_ExecuteProgramOnVM(self):
+        sphere = VSphereTools.Sphere()
+        # TODO: How to check this method if status == 'POWERED ON'? How to check if program and if wait code blocks?
+        with pytest.raises(Exception):
+            sphere.ExecuteProgramOnVM()
+        with pytest.raises(Exception):
+            sphere.ExecuteProgramOnVM(
+                program=r"C:\Windows\System32\cmd.exe",
+                args=r"/T:Green /C echo %aaa% & echo %bbb%",
+                env=r"aaa:10, bbb:20",
+                cwd=r"C:\Windows\System32\\",
+                pythonbin=r"/python32/python",
+                wait=True,
+            )