[semantic][typescript] Constants with function type should be rendered as functions

[IllusionMH]

Issue Type: Bug

If function is declared as const + arrow function it will be hightlighted as variable in editor, but as function in hover.

Is it expected behavior?

/cc @aeschli

VS Code version: Code - Insiders 1.42.0-insider (3c6f6af, 2020-01-27T05:27:06.595Z)
OS version: Windows_NT x64 10.0.18363

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Process Argv
Screen Reader	no
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Extensions: none

[aeschli]

In general, with semantic highlighting there will be difference between code in the editor and code snippets in hovers the's no semantic resultion possible in hovers (lack of context).

The sample that you show is interesting, and not really related to semantic information. The TypeScript TextMate grammar classified fn as a function, but semantic highlighting calls is a variable. So basically the type of the variable is used to figure out that it is a function.
I will fix this in the semantic highlighting code.

[IllusionMH]

So basically the type of the variable is used to figure out that it is a function.

Looks like this is only working with variables, and interesting that TS doesn't highlight properties with arrow functions.

I will fix this in the semantic highlighting code.

So constants with function type will be highlighted as functions (yellow)? That would be awesome!

BTW, TS doesn't highlight unions as function even if all union members are function types 😢

[aeschli]

fixed by aeschli/typescript-vscode-sh-plugin@10f9e7f