SwiftLint 0.16.1 incorrectly converting legacy constant for Swift 2.3

[raid5]

I have a project using Swift 2.3 and have installed version 0.16.1 of SwiftLint. When I run swiftlint autocorrect, it's incorrectly replacing CGFloat(M_PI) with CGFloat.pi. In the logs I see the output of Corrected Legacy Constant where it made the change to my code and the project won't compile due to this error.

[marcelofabri]

I've tried to reproduce it and couldn't. The implementation seems correct too.

The only reason that could make this happen seems to be the wrong toolchain being used (see https://github.com/jpsim/SourceKitten#how-is-sourcekit-resolved).

Using TOOLCHAINS=com.apple.dt.toolchain.Swift_2_3 swiftlint autocorrect should work. Can you test this?

[jpsim]

I think the issue might be that since CGFloat(M_PI) is valid in both Swift 2 and 3, that it doesn't need to be fenced in a version compile-guard (#if swift(>=3.0)), so if you're running SwiftLint in Swift 3 mode, it'll gladly "correct" it to something that doesn't compile in Swift 2.x.

It's not a great experience, but I'd still consider it a "user error".

[raid5]

@marcelofabri, yes specifying the TOOLCHAINS works and does not make the adjustment to CGFloat(M_PI). I wasn't aware this needed to be done as I figured SwiftLint would know what version of Swift to target.

[marcelofabri]

In general this shouldn't be needed. Do you have more than one Xcode installed?

[jpsim]

I wasn't aware this needed to be done as I figured SwiftLint would know what version of Swift to target.

SwiftLint doesn't check the version specified in your Xcode project, or a .swift-version file at the root of your repo. It does leave code alone if it wouldn't compile under its current Swift version (determined via https://github.com/jpsim/SourceKitten#how-is-sourcekit-resolved).

In general this shouldn't be needed. Do you have more than one Xcode installed?

This can happen even with just a single version of Xcode installed, since Xcode 8.x ships with both Swift 3 and Swift 3 toolchains

[raid5]

@marcelofabri, yes I have 7.3.1 and 8.2.1 as I need both for client work.

[raid5]

@jpsim, that makes sense. I may suggest adding something about that to the README.

[jpsim]

See #1239.