add a mock test

Author: MoChilia

src/azure-cli/azure/cli/command_modules/util/_help.py

@@ -97,8 +97,8 @@
 type: command
 short-summary: Create a sandboxed what-if simulation of Azure CLI scripts to visualize infrastructure changes before execution.
 examples:
-- name: Simulate a what-if scenario for a resource group deletion
+- name: Simulate a what-if scenario for a provided script
   text: az what-if --script-path "/path/to/your/script.sh"
 - name: Simulate a what-if scenario for a specific subscription
-  text: az what-if --script-path "/path/to/your/script.sh" --subscription "MySubscription"
+  text: az what-if --script-path "/path/to/your/script.sh" --subscription 00000000-0000-0000-0000-000000000000
 """

src/azure-cli/azure/cli/command_modules/util/tests/latest/test_whatif.py

@@ -0,0 +1,52 @@
+# --------------------------------------------------------------------------------------------
+# Copyright (c) Microsoft Corporation. All rights reserved.
+# Licensed under the MIT License. See License.txt in the project root for license information.
+# --------------------------------------------------------------------------------------------
+
+import unittest
+import os
+from unittest.mock import patch, Mock
+from azure.cli.testsdk import ScenarioTest
+
+TEST_DIR = os.path.dirname(os.path.realpath(__file__))
+
+
+class WhatIfTest(ScenarioTest):
+
+    def setUp(self):
+        super().setUp()
+        self.test_script_path = os.path.join(TEST_DIR, 'test_whatif_script.sh')
+
+    @patch('azure.cli.core.util.send_raw_request')
+    def test_what_if_command_success(self, mock_send_raw_request):
+        mock_response = Mock()
+        mock_response.json.return_value = {
+            "what_if_result": {
+                "changes": [
+                    {
+                        "changeType": "Create",
+                        "resourceId": "/subscriptions/test/resourceGroups/myrg/providers/Microsoft.Compute/virtualMachines/MyVM_01",
+                        "before": None,
+                        "after": {
+                            "name": "MyVM_01",
+                            "type": "Microsoft.Compute/virtualMachines",
+                            "location": "eastus"
+                        }
+                    }
+                ],
+                "potential_changes": [],
+                "diagnostics": []
+            }
+        }
+        mock_send_raw_request.return_value = mock_response
+        result = self.cmd('az what-if --script-path "{}" --no-pretty-print'.format(self.test_script_path))
+        output = result.get_output_in_json()
+        self.assertIsInstance(output, dict)
+        self.assertIn("changes", output)
+        self.assertEqual(len(output["changes"]), 1)
+        self.assertEqual(output["changes"][0]["changeType"], "Create")
+        mock_send_raw_request.assert_called_once()
+
+
+if __name__ == '__main__':
+    unittest.main()