Fixed aggressive directory creation, added support for some nested libraries

book/cookbook/benchmarks/benchmark_aux_dont_execute.ipynb

@@ -53,6 +53,18 @@
     "\n",
     "my_library.hello()"
    ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "# Local library in a folder\n",
+    "\n",
+    "import nested.nested.nested_library\n",
+    "nested.nested.nested_library.hello()"
+   ]
   }
  ],
  "metadata": {

book/cookbook/benchmarks/nested/__init__.py

+# This can be empty

book/cookbook/benchmarks/nested/nested/__init__.py

+# This can be empty

book/cookbook/benchmarks/nested/nested/nested_library.py

+def hello():
+	print("Hello world!")

thebe_lite/_static/_hook_fetch_module_finder.py

@@ -9,19 +9,28 @@ import os
 class FetchPathFinder(importlib.abc.MetaPathFinder):
 	@classmethod
 	def find_spec(cls, fullname, path, target=None):
-		if path is None:
+		if path is None or len(path) == 0:
 			path = os.getcwd()
-		for suffix in importlib.machinery.SOURCE_SUFFIXES:
-			fullpath = os.path.join(path, fullname + suffix)
-			
+		else:
+			path = path[0]
+	
+		module_name = fullname.split(".")[-1]
+		suffixed = [module_name + suffix for suffix in importlib.machinery.SOURCE_SUFFIXES]
+		# Due to the lack of directory listings, we'll just force nested modules to have an __init__.py
+		for relpath in [*suffixed, os.path.join(module_name, "__init__.py")]:
+			fullpath = os.path.join(path, relpath)
 			try:
 				# This will cause a lazy load from the server
 				open(fullpath, "r").close()
 			except:
 				continue
-
+	
 			loader = importlib.machinery.SourceFileLoader(fullname, fullpath)
 			return importlib.util.spec_from_loader(fullname, loader=loader)
 		return None
+		
+	@classmethod
+	def invalidate_caches(cls):
+		return
 
-sys.meta_path.append(FetchPathFinder)
\ No newline at end of file
+sys.meta_path.append(FetchPathFinder)

thebe_lite/_static/sphinx-thebe.js

@@ -325,8 +325,6 @@ function override_pyodide_lookup(fs, server_path) {
       const name = pathList[pathList.length - 1]; // Name of file
       const parentPathList = pathList.slice(0, -1); // List of all parent directories
 
-      createDirectoryStructure(parentPathList);
-
       let request = new XMLHttpRequest();
       request.open("GET", path, false);
       request.send();
@@ -334,6 +332,7 @@ function override_pyodide_lookup(fs, server_path) {
       if (request.status !== 200) {
         throw exception;
       }
+      createDirectoryStructure(parentPathList);
       createFileFromString(parentPathList.join("/"), name, request.response);
       return old_lookup(fullPath, opts);
     }
@@ -426,11 +425,11 @@ var initThebe = async () => {
   // 3. Eval the string og the override_pyodide_lookup function in JS, this brings it into scope
   // 4. Execute the override_pyodide_lookup function in JS, and bake in the relative path from root in the book (the home)
   // NOTE: All functions used in override_pyodide_lookup should be nested inside it, since the web worker cannot access functions in this script
-  await thebelab.session.kernel.requestExecute({
+  thebelab.session.kernel.requestExecute({
     code: `import js; import pyodide_js; js.fs = pyodide_js.FS; js.eval("""${override_pyodide_lookup.toString()}"""); js.eval(f"override_pyodide_lookup(fs, '${
       location.pathname.split("/").slice(0, -1).join("/") + "/"
     }')")`,
-  }).done;
+  });
 
   const request = new XMLHttpRequest();
   request.open("GET", "/_static/_hook_fetch_module_finder.py", false);
@@ -439,9 +438,9 @@ var initThebe = async () => {
   const fetchImportHookCode = request.response;
 
   // Enable importing of modules on server
-  await thebelab.session.kernel.requestExecute({
+  thebelab.session.kernel.requestExecute({
     code: fetchImportHookCode,
-  }).done;
+  });
 
   // Fix for issues with ipywidgets in Thebe
   await thebelab.session.kernel.requestExecute({