Add a code fix for should-have-been-array#3330
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It's a pretty common mistake to pass a single control qubit to a function or functor that expects an array of them. Add a code fix detecting that this has occurred and offering to add square brackets. To make this possible, attach info about the expected and actual types to the ErrorKind. (Unfortunately, Ty is hard to share, so create a simpler TyInfo that can accompany the ErrorKind.)
amcasey
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amcasey
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Jun 13, 2026
| #[test] | ||
| fn array_to_nested_array() { | ||
| // Qubit[] passed where Qubit[][] expected - wrapping in [...] is valid. | ||
| // Qubit[] isn't a primitive type, but it's actually complaining at the element |
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I don't love this, but I wasn't convinced it was worth "breaking" it for consistency. If we care, I think we can ask the compiler for the type of the expression at the error span and force that to be a primitive too.
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I did it, but I'd just as soon revert the new commit.
amcasey
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Jun 13, 2026
| #[error("expected {0}, found {1}")] | ||
| #[diagnostic(code("Qsc.TypeCk.TyMismatch"))] | ||
| TyMismatch(String, String, #[label] Span), | ||
| TyMismatch( |
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We talked about adding a new ErrorKind, but I thought enriching this one gave us more flexibility when creating future code actions.
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It's a pretty common mistake to pass a single control qubit to a function or functor that expects an array of them. Add a code fix detecting that this has occurred and offering to add square brackets.
To make this possible, attach info about the expected and actual types to the ErrorKind. (Unfortunately, Ty is hard to share, so create a simpler TyInfo that can accompany the ErrorKind.)