"editor.suggestSelection": "recentlyUsed" frozen?

[jabacchetta]

• VSCode Version: 1.36.1
• OS Version: macOS Mojave 10.14.4
• Does this issue occur when all extensions are disabled?: Yes

In certain files of a project, I'm apparently getting a recently used completion that I can't reset (I've tried all the clear commands).

But more importantly than being able to reset it, it seems like "recently used" could be improved on to take into account more factors (e.g. context and how recently).

See the screenshot below, where a word suggestion continues to be selected regardless of how many times I autocomplete something else (i.e. slice).

[jrieken]

Please provide repro steps

[jabacchetta]

OK, took me some experimenting to figure out how to reproduce this, but think I figured it out.

1. Add the following settings:

{
  // // TODO: See if TypeScript has the same issue
  // "typescript.suggest.completeFunctionCalls": true,

  // `completeFunctionCalls` appears to be the problematic setting
  "javascript.suggest.completeFunctionCalls": true
}

2. Create a JavaScript file with the following code:

const num = 1;
const str = 'foo';

3. Type str.n and then accept/autocomplete the word based, num suggestion.

4. Type str.sl and accept the slice suggestion.

5. Type in str. and notice that num is still being prioritized as the most recent autocompletion (when slice should be prioritized at this point).

6. Remove the completeFunctionCalls setting given above.

7. Repeat steps 3-5 above. But this time, notice that the slice suggestion is properly being prioritized.

[jrieken]

This is an issue with TypeScript as it seems that the insertText differs, sometimes it's just .slice and sometimes it's .slice($1)$0. The LRU suggest memory selects recent item based on language, completion type, and insert text and if that differs an item isn't selected.

[mjbvz]

@jrieken Thanks for the investigation. Here's more detail on why this is happening:

1. In provideCompletionItems, we always return basic completion items with insert text such as .slice.
2. We only create the snippet based completions (such as .slice($1)$0) when the compeletion item is resolved
3. After accepting a completion, the suggestion memory stores the resolved completion item. When the next completion request comes in, it then tries matching the stored resolved completion item against unresolved completion items. This fails for .slice($1)$0

Do you think this is something we could fix in VS Code itself? Any potential workarounds? We can't eagerly resolve the insert text for JS/TS as that can be an expensive operation

[jrieken]

We only create the snippet based completions (such as .slice($1)$0) when the compeletion item is resolved

⬆️ That is the issue, actually the cause of multiple issues. The resolve-call should never change the insert behaviour of a completion. It was a mistake not to enforce that because it's the root of much evil.

We can't eagerly resolve the insert text for JS/TS as that can be an expensive operation

I honestly think we must do that. With #73311 we already realised that items must be resolved asap and that we cannot wait once we show them. The only fix on our side I see is to forcefully call resolve before showing items - defeating the purpose of resolve...

[mjbvz]

Ok, I will look to see what the cost of creating the insert text eagerly and if it is even possible to do with the existing TS api

[mjbvz]

Ok, I investigated this and found we cannot fix this on the JS/TS side without dropping support for completeFunctionCalls.

The reason is that completeFunctionCalls generates the insert text using the displayText that typescript returns when resolving completion items. Doing this eagerly for all completion items would be expensive.

This request against TS may be relevant: microsoft/TypeScript#25207

Moving to backlog since I don't know how to fix it this iteration

[mjbvz]

Closing this due to lack of further user feedback over the past year.

Long term, I feel that we should move completeFunctionCalls to TypeScript with microsoft/TypeScript#25207