Maybe I'm searching for the wrong stuff, but grepping for the error message from the linked tweet, "could not find overload for '*' that accepts supplied arguments", doesn't turn up any hits (even subsets like just "overload" or "supplied" don't show anything seemingly related). I tried git log -S to search for whether these diagnostics were removed, but with limited success.

Using Swift 4.0 from Xcode 9, the following code:

enum Foo: Int {
    case bar
}

let result = Foo.bar.rawValue * CGFloat(0)

This yields this error: Binary operator '*' cannot be applied to operands of type 'Int' and 'CGFloat'. Am I correct in understanding that this task suggests a fix-it should be added that suggests adding CGFloat(Foo.bar.rawValue)?

Yeah, if there's an explicit numeric conversion that could make the system type-check, it'd be nice if we suggested it.

Comment by Matthew Cheok (JIRA)

I'd like to start contributing with this task but I've no idea where to start. Can I get some pointers?

Thanks matthewcheok (JIRA User)! I'm not the expert on the type checker (@DougGregor, @xedin, and @rudkx definitely know better than I do), but I think a good place to start might be to look at how we handle the fixits for missing bridging conversions when ObjC interop is enabled:

import Foundation

func foo(x: NSString) {}

func bar(x: String) { foo(x: x) } // the compiler sees the String-NSString mismatch here and suggests `as NSString`

Comment by Takeru Chuganji (JIRA)

PR merged: #13272

Awesome!