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[kimdv]

Description

From #2286 (comment)

Hmm, it’s not easily possible in the current design where we assume all nodes for the Fix-It to already be present in the syntax tree so that we just need to flip the token presence.

I would say that it’s good enough for now but adding support for these kinds of Fix-Its might be useful in general. What we need for that is, IMO, a new Fixit.Change that takes a syntax node, a key path within that node and a replacement node, i.e. something like case replace<NodeType, ChildType>(node: NodeType, path: KeyPath<NodeType, ChildType>, child: ChildType) – and yes I see the irony of declaring a generic enum case here, you would need to come up with some design that actually compiles, I haven’t thought about it too much yet.

I think this kind of Fix-It change might also be useful for macro authors. IIRC it came up once or twice but was never super important.

[ahoppen]

Tracked in Apple’s issue tracker as rdar://117082263

[kimdv]

Close in favour of #2205