Backport PR #1714: Fix: Drive issue on rewritting JSON file (#1716)

Co-authored-by: martinRenou <martin.renou@gmail.com>

packages/contents/src/drivecontents.ts

@@ -225,7 +225,7 @@ export class DriveContentsProcessor implements IDriveContentsProcessor {
   async put(request: TDriveRequest<'put'>): Promise<TDriveResponse<'put'>> {
     await this.contentsManager.save(request.path, {
       content:
-        request.data.format === 'json'
+        request.data.format === 'json' && request.data.data
           ? JSON.parse(request.data.data)
           : request.data.data,
       type: 'file',

ui-tests/contents/file-access-3.ipynb

@@ -0,0 +1,46 @@
+{
+ "cells": [
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "e3c4d1de",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "s = R\"\"\"\n",
+    "{\n",
+    "  \"args\": {}\n",
+    "}\n",
+    "\"\"\"\n",
+    "import json\n",
+    "\n",
+    "data = json.loads(s)\n",
+    "with open(\"data.json\", \"w\") as f:\n",
+    "    json.dump(data, f)\n",
+    "with open(\"data.json\", \"w\") as f:\n",
+    "    json.dump(data, f)"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python (Pyodide)",
+   "language": "python",
+   "name": "python"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.9.7"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 5
+}

ui-tests/test/service-worker.spec.ts

@@ -95,4 +95,13 @@ test.describe('Service Worker Tests', () => {
     expect(output).toBeTruthy();
     expect(output![0]).toContain(expectedOutput);
   });
+
+  test('Create a JSON file twice does not crash the kernel', async ({ page }) => {
+    const notebook = 'file-access-3.ipynb';
+
+    await page.menu.clickMenuItem('Settings>Autosave Documents');
+
+    await page.notebook.open(notebook);
+    await page.notebook.runCellByCell();
+  });
 });