Issue with Untrusted to Trusted Workspaces in Jupyter Notebooks

[eleanorjboyd]

Currently the python extension is stalling when attempting to execute functionality following the change from a untrusted to trusted workspace. When a file is originally opened in an untrusted workspace, then switched to trusted, the follow jupyter notebook operations performed by the user will stall and not complete. Dev tools will show the following error about the client not be available.

Steps to reproduce:

1. Open new workspace, click do not trust
2. Make a new Jupyter notebook
3. Attempt to run code in the notebook
4. Check in dev tools, an error should have appeared
5. VS Code will now stall and be stuck on that run command

We have also determined this issue does not happen when you originally check trust when opening a new workspace. If you make it a trusted workspace from the beginning, then try and run code in a jupyter notebook, the code will return and no error will appear in the dev tools windows.

From the code on the python side, we are able to know that the user has switched to a trusted workspace, and doing this action does not cause a problem. The problem arises when attempting to run a notebook and the client error surfaces.

[sbatten]

The error seems to be coming from the python side when trying to talk to the language server client. I wonder if the client is started too close to the transition from workspace trust.

vscode-python/src/client/activation/node/languageServerProxy.ts

Line 102 in 133a8e8

this.workspace.onDidGrantWorkspaceTrust(() => {

[sbatten]

I verified that this is not a regression in either the extension or core, but it seems like the Python extension either tries to access its client too early or our notification of workspace trust to extensions is too early. I'd need to confirm in the extension first.