An `ng-template` with an inline template (i.e. has a structural
directive) would previously not get an `undefined` `tagName` because the
logic assumed the element would be `t.Element` or `t.Content` and read
the tag name from the `name` property. For a `t.Template`, this exists
instead on the `t.tagName`. The final result would be an `tagName` of `undefined`
for the parent `t.Template`, causing failures in the indexer downstream.
This `undefined` value is actually expected in the renderer code, even
though the type does not specify this possibility. This change updates
the type of `tagName` to be `string|null` and explicitly handles the
case where there is a structural directive on an `ng-template`. You can
see how the two are differentiated in the compliance code that was
modified in this commit.
PR Close#44788
1bce51c0ed