Do not treat replaceable TypeVariableNode instances as noops - #1722
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| // if in a type alias, this node will be replaced by another TypeNode that may not be a noop | ||
| // so we return false so that containing TypeNodes don't skip checks erroneously | ||
| // this is slightly less efficient if the replacement _is_ a noop, but only inside typealiases | ||
| return !isInTypeAlias; |
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We should never hit the case where isNoopTypeCheck() is called when this is inside a typealias, because these nodes should be replaced before the alias can ever run.
Also: I feel that we should replace the usage of TypeVariableNode in other positions (e.g. function <T>(foo: T)) with TypeNode.Unknown, at least until we have support for type arguments there. Probably would be better if TypeVariableNode never gets fired.
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This also fixes
TypeAliasTypeNodealways performing lazy type checks even when they should be eager.Resolves #1710
Resolves #1716
Supersedes #1717