[Storage] az storage fs file list: Support --show-next-marker (Azur…

…e#17408)

* `az storage fs file list`: Support --show-next-marker

src/azure-cli/azure/cli/command_modules/storage/_params.py

@@ -1603,6 +1603,8 @@ def load_arguments(self, _):  # pylint: disable=too-many-locals, too-many-statem
                    help='An opaque continuation token. This value can be retrieved from the next_marker field of a '
                    'previous generator object. If specified, this generator will begin returning results from this '
                    'point.')
+        c.argument('show_next_marker', action='store_true', is_preview=True,
+                   help='Show nextMarker in result when specified.')
 
     for item in ['create', 'show', 'delete', 'exists', 'upload', 'append', 'download', 'show', 'metadata update',
                  'metadata show']:

src/azure-cli/azure/cli/command_modules/storage/operations/fs_file.py

@@ -69,15 +69,20 @@ def get_file_properties(client, timeout=None):
     return result
 
 
-def list_fs_files(client, path=None, recursive=True, num_results=None, timeout=None, exclude_dir=None, marker=None):
+def list_fs_files(client, path=None, recursive=True, num_results=None, timeout=None, exclude_dir=None,
+                  marker=None, show_next_marker=None):
     generator = client.get_paths(path=path, max_results=num_results, recursive=recursive, timeout=timeout)
     pages = generator.by_page(continuation_token=marker)
 
-    result = next(pages)
+    result = list(next(pages))
 
-    if pages.continuation_token:
-        logger.warning('Next Marker:')
-        logger.warning(pages.continuation_token)
+    if show_next_marker:
+        next_marker = {"nextMarker": pages.continuation_token}
+        result.append(next_marker)
+    else:
+        if pages.continuation_token:
+            logger.warning('Next Marker:')
+            logger.warning(pages.continuation_token)
 
     if exclude_dir:
         return list(f for f in result if not f.is_directory)