Code Completions for Object's keys behave differently in different declaration scenarios

I tried these code snippets in monaco editor playground
I'm posting it here, as those were reproducible in VsCode too
VsCode Version: 1.52.0
Commit: 940b5f4bb5fa47866a54529ed759d95d09ee80be
Date: 2020-12-10T22:46:53.673Z
Electron: 9.3.5
Chrome: 83.0.4103.122
Node.js: 12.14.1
V8: 8.3.110.13-electron.0
OS: Darwin x64 17.7.0

1. When an Object in constructed with some keys and manipulated by some other keys then, those manipulated keys wont find its place in the suggestions ( as a property ). It only comes in suggestion as a literal

Here, key3 is not suggested as property of the object

2. When an Object is initialized with an empty object and then if it is reassigned, then only the directly manipulated keys are shown in suggestions

Here, Only key3 is suggested as property of the object and not the other keys

3. When an Object is initialized with an empty object and then if it is only manipulated ( one at a time ) then it works perfectly fine

Originally posted by @Pranomvignesh in https://github.com/microsoft/monaco-editor/issues/2278#issuecomment-749024514

まず、issue で説明されている 3 つのオブジェクト宣言シナリオを Monaco Editor playground と VS Code で再現します。オブジェクトキーに対する TypeScript の completion の動作を追跡し、異なる候補が期待されるものかどうかを判断します。完了の条件は、報告されたシナリオでプロパティ補完が一貫していることです。関連するテスト箇所が見つかった場合は、回帰テストのカバレッジも追加します。