[Resource] Cover generated snapshot deployment names

Co-authored-by: a0x1ab <59631311+a0x1ab@users.noreply.github.com>

Author: Copilot

src/azure-cli/azure/cli/command_modules/resource/custom.py

@@ -62,6 +62,8 @@
 
 logger = get_logger(__name__)
 
+_CLI_GENERATED_DEPLOYMENT_NAME_PATTERN = re.compile(r'azurecli\d+\.\d+')
+
 RPAAS_APIS = {'microsoft.datadog': '/subscriptions/{subscriptionId}/providers/Microsoft.Datadog/agreements/default?api-version=2020-02-01-preview',
               'microsoft.confluent': '/subscriptions/{subscriptionId}/providers/Microsoft.Confluent/agreements/default?api-version=2020-03-01-preview'}
 
@@ -4651,7 +4653,7 @@ def snapshot_bicep_file(cmd, file, mode=None, tenant_id=None, subscription_id=No
             args += ["--location", location]
         if resource_group:
             args += ["--resource-group", resource_group]
-        if deployment_name and not re.fullmatch(r'azurecli\d+\.\d+', deployment_name):
+        if deployment_name and not _CLI_GENERATED_DEPLOYMENT_NAME_PATTERN.fullmatch(deployment_name):
             args += ["--deployment-name", deployment_name]
 
         output = run_bicep_command(cmd.cli_ctx, args)

src/azure-cli/azure/cli/command_modules/resource/tests/latest/test_resource_bicep.py

@@ -343,6 +343,21 @@ def test_snapshot_bicep_file_ignores_generated_deployment_name(
 
         run_bicep_command_mock.assert_called_once_with(self.cli_ctx, ["snapshot", "main.bicepparam"])
 
+    @mock.patch("azure.cli.command_modules.resource.custom.run_bicep_command")
+    @mock.patch("azure.cli.command_modules.resource.custom.bicep_version_greater_than_or_equal_to")
+    @mock.patch("azure.cli.command_modules.resource.custom.ensure_bicep_installation")
+    def test_snapshot_bicep_file_passes_similarly_named_deployment_name(
+        self, ensure_bicep_installation_mock, bicep_version_check_mock, run_bicep_command_mock
+    ):
+        bicep_version_check_mock.return_value = True
+        run_bicep_command_mock.return_value = ""
+
+        snapshot_bicep_file(self.cmd, "main.bicepparam", deployment_name="azurecli123")
+
+        run_bicep_command_mock.assert_called_once_with(
+            self.cli_ctx, ["snapshot", "main.bicepparam", "--deployment-name", "azurecli123"]
+        )
+
     @mock.patch("azure.cli.command_modules.resource.custom.run_bicep_command")
     @mock.patch("azure.cli.command_modules.resource.custom.bicep_version_greater_than_or_equal_to")
     @mock.patch("azure.cli.command_modules.resource.custom.ensure_bicep_installation")