Improve performance of completions #1750
Description
As well as probably being the cause of #1721, the performance of completions with unimported symbols is generally poor.
Testing on Windows PC with the following test (inside test\flutter_only\providers\completion_item_provider.test.ts):
describe("with SuggestionSet support", () => {
beforeEach("ensure SuggestionSets are supported", function () {
if (!extApi.analyzerCapabilities.supportsAvailableSuggestions)
this.skip();
});
it.only("includes unimported symbols", async () => {
await setTestContent(`
main() {
ProcessInf
}
`);
const count = 50;
const start = Date.now();
for (let i = 0; i < 50; i++) {
const completions = await getCompletionsAt("ProcessInf^");
ensureCompletion(completions, vs.CompletionItemKind.Class, "ProcessInfo", "ProcessInfo");
}
const end = Date.now();
console.log(`Took ${end - start}ms to do ${count} completion requests`);
});
});
Output from a few runs:
Took 56426ms to do 50 completion requests
Took 57034ms to do 50 completion requests
Took 57607ms to do 50 completion requests