Allowed trailing commas in type argument lists for type references

[brainkim]

TypeScript Version: 3.1.0-dev.201xxxxx

Search Terms:
Trailing Comma Nested Types Parameters Generic

Code:

interface Pizza<T> {
  pizza: T;
}

type PizzaBox = Partial<Pizza<string,>>;

Expected behavior:
An error should not be thrown
Actual behavior:

pizza.ts:5:37 - error TS1009: Trailing comma not allowed.

5 type PizzaBox = Partial<Pizza<string,>>;

Playground Link:
http://www.typescriptlang.org/play/index.html#src=interface%20Pizza%3CT%3E%20%7B%0D%0A%20%20pizza%3A%20T%3B%0D%0A%7D%0D%0A%0D%0Atype%20PizzaBox%20%3D%20Partial%3CPizza%3Cstring%2C%3E%3E%3B
Related Issues:
#16152
#21984
#20599

[mhegazy]

Do not think nesting has any thing to do with this. it is the type reference that is not allowed. related to #21984

[mhegazy]

Actually, i would just call this a duplicate of #21984

[brainkim]

@mhegazy You would know better!

[typescript-bot]

Automatically closing this issue for housekeeping purposes. The issue labels indicate that it is unactionable at the moment or has already been addressed.