vscode-extension-samples/fsprovider-sample

MemFS

This extension implements an in-memory file system to show-case a API. It also enables to see how other extensions behave with documents/files that aren't stored on disk.

To get started you need the extension and a workspace with an entry like this:

{
  "uri": "memfs:/",
  "name": "MemFS"
}

Then, select 'F1 > Initialize MemFS' and notice how the file explorer is populated with some files.