Update file_explorer.py - Fixing error if nothing selected in file_co…

…unt=single mode (return None rather) (#6607)

* Update file_explorer.py

Fixing error if nothing selected in file_count=single mode (return None rather)

* add changeset

* added unit tests

---------

Co-authored-by: Abubakar Abid <abubakar@huggingface.co>
Co-authored-by: gradio-pr-bot <gradio-pr-bot@users.noreply.github.com>

.changeset/early-fans-work.md

@@ -0,0 +1,5 @@
+---
+"gradio": patch
+---
+
+fix:Update file_explorer.py - Fixing error if nothing selected in file_count=single mode (return None rather)

gradio/components/file_explorer.py

@@ -112,7 +112,10 @@ def preprocess(self, payload: FileExplorerData | None) -> list[str] | str | None
                 raise ValueError(
                     f"Expected only one file, but {len(payload.root)} were selected."
                 )
-            return self._safe_join(payload.root[0])
+            elif len(payload.root) == 0:
+                return None
+            else:
+                return self._safe_join(payload.root[0])
 
         return [self._safe_join(file) for file in (payload.root)]
 

test/test_components.py

@@ -31,6 +31,7 @@
 import gradio as gr
 from gradio import processing_utils, utils
 from gradio.components.dataframe import DataframeData
+from gradio.components.file_explorer import FileExplorerData
 from gradio.components.video import VideoData
 from gradio.data_classes import FileData
 
@@ -2647,6 +2648,46 @@ def fn(a):
         }
 
 
+class TestFileExplorer:
+    def test_component_functions(self):
+        """
+        Preprocess, get_config
+        """
+        file_explorer = gr.FileExplorer(file_count="single")
+
+        config = file_explorer.get_config()
+        assert config["glob"] == "**/*.*"
+        assert config["value"] is None
+        assert config["file_count"] == "single"
+        assert config["server_fns"] == ["ls"]
+
+        input_data = FileExplorerData(root=[["test/test_files/bus.png"]])
+        preprocessed_data = file_explorer.preprocess(input_data)
+        assert isinstance(preprocessed_data, str)
+        assert Path(preprocessed_data).name == "bus.png"
+
+        input_data = FileExplorerData(root=[])
+        preprocessed_data = file_explorer.preprocess(input_data)
+        assert preprocessed_data is None
+
+        file_explorer = gr.FileExplorer(file_count="multiple")
+
+        config = file_explorer.get_config()
+        assert config["glob"] == "**/*.*"
+        assert config["value"] is None
+        assert config["file_count"] == "multiple"
+        assert config["server_fns"] == ["ls"]
+
+        input_data = FileExplorerData(root=[["test/test_files/bus.png"]])
+        preprocessed_data = file_explorer.preprocess(input_data)
+        assert isinstance(preprocessed_data, list)
+        assert Path(preprocessed_data[0]).name == "bus.png"
+
+        input_data = FileExplorerData(root=[])
+        preprocessed_data = file_explorer.preprocess(input_data)
+        assert preprocessed_data == []
+
+
 def test_component_class_ids():
     button_id = gr.Button().component_class_id
     textbox_id = gr.Textbox().component_class_id