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• Updated SwiftLint to the latest version
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Describe the bug

empty_count violation is triggered on extension over IteratorProtocol

Sample code:

extension IteratorProtocol {
    mutating func skip(_ count: Int) {
        guard count > 0 else { return } // ERROR: Empty Count Violation: Prefer checking `isEmpty` over comparing `count` to zero (empty_count)

        for _ in 0..<count {
            _ = next()
        }
    }
}

Complete output when running SwiftLint, including the stack trace and command used

$ swiftlint lint

Environment

• SwiftLint version (run swiftlint version to be sure)?
• Installation method used (Homebrew, CocoaPods, building from source, etc)?
• Paste your configuration file:

# insert yaml contents here

• Are you using nested configurations?
  If so, paste their relative paths and respective contents.
• Which Xcode version are you using (check xcodebuild -version)?
• Do you have a sample that shows the issue? Run echo "[string here]" | swiftlint lint --no-cache --use-stdin --enable-all-rules
  to quickly test if your example is really demonstrating the issue. If your example is more
  complex, you can use swiftlint lint --path [file here] --no-cache --enable-all-rules.