@allevato I'm wondering if you have any thoughts on this; I want to make sure I'm understanding everything correctly and that there aren't any other logic bugs. We insert aprinterControl token on an ImportDecl node that disables breaking, which seems to disableall breaking other than.hard (is this correct?). Since we can have an#if clause at the beginning of an ImportDecl statement, that would imply we need a.hard line break at the end of each condition, as well as the#endif. However, I believe a hard line break may give us too many newlines in other contexts where breaking is enabled. But the newlines are absolutely required, so maybe this is the best approach anyway? Or maybe the pretty print features aren't interacting the way they're intended to...

I think we want to keep theoverall stylistic idea that "imports look better all on one line", and so we only need to fix that logic specifically for imports that have#if-surrounded attributes. (There's value to having one-line imports in the general case; other than just having them look better when they're a block at the top of the file, naïve regex-based tools can scan imports without having to do a full parse or require swift-syntax.)

So, I think we can address this a different way. What if, inTokenStreamCreator.visit(ImportDeclSyntax), we just check to see if the decl'sattributes contain anyIfConfigDecls? If it does, move the printer control token to precede theimportKeyword token instead of the attribute list. Then, it will allow the attributes to span multiple lines (fixing the#if case) without causing unwanted wrapping for simpler imports.

Sure, that breaks the promise we're making to simpler tools that might want to quickly scan for those imports, but they were never going to handle something that complicated anyway without a full parse (and#if config evaluation).

That sounds like a more promising approach than what I'd considered so far, so I'll give that a try. Thanks for your thoughts!