Unit testing code for modules/sonic_command.py added (#219)

* Unit testing code for modules/sonic_command.py added

* Enhanced UT code to validate the output from sonic_command module

* removed unwanted print and debug statements which in turn resolved the sanity errors

tests/unit/modules/network/sonic/fixtures/sonic_command.yaml

@@ -0,0 +1,12 @@
+---
+merged_01:
+  module_args:
+    commands:
+      - show version
+    retries: 5
+    interval: 3
+    wait_for:
+      - result[0] contains Version
+    match: any
+  expected_command_requests:
+    - show version

tests/unit/modules/network/sonic/test_sonic_command.py

@@ -0,0 +1,59 @@
+from __future__ import absolute_import, division, print_function
+
+__metaclass__ = type
+
+from ansible_collections.dellemc.enterprise_sonic.tests.unit.compat.mock import (
+    patch,
+)
+from ansible_collections.dellemc.enterprise_sonic.plugins.modules import (
+    sonic_command,
+)
+from ansible_collections.dellemc.enterprise_sonic.tests.unit.modules.utils import (
+    set_module_args,
+)
+from .sonic_module import TestSonicModule
+
+
+class TestSonicInterfacesModule(TestSonicModule):
+    module = sonic_command
+
+    @classmethod
+    def setUpClass(cls):
+        cls.mock_run_commands = patch(
+            "ansible_collections.dellemc.enterprise_sonic.plugins.modules.sonic_command.run_commands"
+        )
+        cls.fixture_data = cls.load_fixtures('sonic_command.yaml')
+
+    def run_commands_side_effect(self, module, commands):
+        """Side effect function for run commands  mock"""
+
+        for cmd in commands:
+            self.config_commands_sent.append(cmd['command'])
+        # Purpose of the Unit testing for sonic_command is to check whether the passed command goes to device.
+        # Response from device is validated against the expected values.
+        # Simulate a dummy return value for the "show version" command that is being unit tested.
+        return ['Software Version : dell_sonic_4.x_share.770-0beb2c821\n']
+
+    def validate_config_commands(self):
+        """Check if both list of requests sent and expected are same"""
+
+        self.assertEqual(len(self.config_commands_valid), len(self.config_commands_sent))
+        for valid_command, sent_command in zip(self.config_commands_valid, self.config_commands_sent):
+            self.assertEqual(valid_command, sent_command)
+
+    def setUp(self):
+        super(TestSonicInterfacesModule, self).setUp()
+        self.config_commands_sent = []
+        self.config_commands_valid = []
+        self.run_commands = self.mock_run_commands.start()
+        self.run_commands.side_effect = self.run_commands_side_effect
+
+    def tearDown(self):
+        super(TestSonicInterfacesModule, self).tearDown()
+        self.mock_run_commands.stop()
+
+    def test_sonic_commands_merged_01(self):
+        set_module_args(self.fixture_data['merged_01']['module_args'])
+        self.config_commands_valid = self.fixture_data['merged_01']['expected_command_requests']
+        result = self.execute_module(changed=False)
+        self.validate_config_commands()