Intellisense does not work for properties that are added after declaration

[mjbvz]

From @saravanaj on December 30, 2016 3:8

• VSCode Version: 1.8.1
• OS Version: Windows 8.1 Home

I am running code with --disable-extensions flag.

Steps to Reproduce:

1. Write some code where properties are added to objects added after declaration. Intellisense does not work:
   

2. If the properties are defined during declaration it works:
   

Copied from original issue: microsoft/vscode#17923

[mjbvz]

From @Spown on December 31, 2016 4:13

I think it is a proper behavior. If you had something like this:

var obj = {};
if (someGlobalVariable===true) {
  obj.test = {
    one: 1
  }
} else if (someGlobalVariable===false) {
  obj.test = "I'm a string now!"
}

obj

then Intellisense wouldn't really know whether the obj variable always has this test property and what type it is. Intellisense doesn't evaluate your code - it only makes assumptions where it can. Thats why you still have word suggestions:

as a compromise.

[mjbvz]

From @saravanaj on December 31, 2016 6:26

@Spown I agree it is impossible to autocomplete properties that are added conditionally, but the example I posted does not add any properties conditionally. The same code gives intellisense in Visual Studio.

The major use case where this type of intellisense is needed is when I namespace methods and properties like below:

In VS Code:

In Visual Studio: (which handles this perfectly)

[mjbvz]

I verified this intellisense limitation for JS using both TS 2.1.5 and typescript@next.

I believe it may be a duplicate of an existing issue but wasn't able to find a proper parent, so feel free to mark it as such if that is the case. We already handle property assignment to the prototype for classes, so this may be similar.

[unional]

Please note that obj = {}; // without var doesn't work either. This prevent JavaScript namespacing across multiple files.

microsoft/vscode#18196 (comment)

[mhegazy]

This is a duplicate of #7632