fix the using issue in dotnet examples (#8664)

Author: ArcturusZhang

tools/azure-rest-api-specs-examples-automation/ci.yml

@@ -38,6 +38,11 @@ stages:
     - task: GoTool@0
       inputs:
         version: $(GoVersion)
+    
+    - script: |
+        pip install parameterized
+      displayName: 'Install python unittest dependencies'
+      workingDirectory: ./tools/azure-rest-api-specs-examples-automation
 
     - script: |
         python -m unittest discover .

tools/azure-rest-api-specs-examples-automation/dotnet/main.py

@@ -81,15 +81,32 @@ def get_dotnet_example_method(lines: List[str], start: int) -> DotNetExampleMeth
 
 
 def get_dotnet_using_statements(lines: List[str]) -> List[str]:
-    lines_using_statements = []
+    lines_using_statements = [
+        # these are some using statements that every sample program should use.
+        "using Azure;\n",
+        "using Azure.ResourceManager;\n"
+    ]
     for line in lines:
         if line.startswith('using '):
             lines_using_statements.append(line)
-        elif line.startswith('namespace ') and not line.rstrip().endswith(".Samples"):
+        elif line.startswith('namespace '):
+            # remove the prefix first
             namespace = line[len('namespace '):].strip()
+            # remove the '.Samples' suffix if any
+            if namespace.endswith('.Samples'):
+                namespace = namespace[:-len('.Samples')]
             lines_using_statements.append(f'using {namespace};\n')
             break
-    return lines_using_statements
+    return deduplicate_list(lines_using_statements)
+
+def deduplicate_list(list: List[str]) -> List[str]:
+    seen = set()
+    result: List[str] = []
+    for item in list:
+        if item not in seen:
+            seen.add(item)
+            result.append(item)
+    return result
 
 
 def break_down_aggregated_dotnet_example(lines: List[str]) -> AggregatedDotNetExample:

tools/azure-rest-api-specs-examples-automation/dotnet/test_main.py

@@ -1,6 +1,6 @@
 import unittest
-from main import break_down_aggregated_dotnet_example, format_dotnet
-
+import parameterized
+from main import break_down_aggregated_dotnet_example, format_dotnet, get_dotnet_using_statements
 
 file_content = '''// Copyright (c) Microsoft Corporation. All rights reserved.
 // Licensed under the MIT License.
@@ -338,3 +338,34 @@ def test_break_down_aggregated_dotnet_example(self):
             example_lines = examples.class_opening + format_dotnet(dotnet_example_method.content)
             example_content = ''.join(example_lines)
             self.assertIsNotNone(example_content)
+
+    @parameterized.parameterized.expand(
+        [
+            ('''// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+// <auto-generated/>
+
+#nullable disable
+
+using System;
+using System.Threading.Tasks;
+using Azure.Core;
+using Azure.Identity;
+using Azure.ResourceManager.Compute.Models;
+using Azure.ResourceManager.Resources;
+using Azure.ResourceManager.Resources.Models;
+
+namespace Azure.ResourceManager.Compute.Samples
+{
+}''')
+        ]
+    )
+    def test_example_usings(self, content: str):
+        lines = content.splitlines(keepends=True)
+        usings = get_dotnet_using_statements(lines)
+
+        self.assertIn('using Azure;\n', usings)
+        self.assertIn('using Azure.Core;\n', usings)
+        self.assertIn('using Azure.ResourceManager;\n', usings)
+        self.assertIn('using Azure.ResourceManager.Compute;\n', usings)