<reference lib="..." /> directives aren't included in output declaration files

[RikkiGibson]

TypeScript Version: 3.1.0-dev.20180813

Search Terms:
reference lib directive type declarations

Code

/// <reference lib="dom" />

interface ElementHolder {
  elem: HTMLElement;
}

Expected behavior:
When running tsc test.ts --declaration, a declaration file equivalent to the below is emitted.

/// <reference lib="dom" />

interface ElementHolder {
  elem: HTMLElement;
}

Actual behavior:
The following declaration is emitted.

interface ElementHolder {
  elem: HTMLElement;
}

Playground Link:
N/A because Playground does not emit .d.ts files

Related Issues:
Did not find any similar looking bugs

[RyanCavanaugh]

@weswigham can you elaborate on the lib directive emit rules?

[weswigham]

I'd ask @rbuckton actually - I'm not aware of what the lib reference declaration emit rules are, if we even have any.

[rbuckton]

We probably should be emitting these to the declaration file as well.

[RikkiGibson]

Thank you!