Test: search provider API

[roblourens]

Test for #47058

Complexity: 2

• AnyOS @chrmarti

Steps:

• Write a simple extension that uses the SearchProvider API. See an example at https://github.com/Microsoft/vscode-extension-samples/blob/roblou/searchProviderExample/fsprovider-sample/src/searchProvider.ts
• File issues if you have any issues getting results to show up, or if any part of the API itself is confusing.

[chrmarti]

@roblourens I can't get it to work with todays insiders build and also tried MemFS. The search provider is never called.

[roblourens]

Did you set "search.enableSearchProviders": true? Forgot to mention that in the steps since it's no longer the default.

[chrmarti]

That makes it work. 👍