public func rewritePacket(packet: IPMutablePacket) -> IPMutablePacket? {
        // Support only TCP as for now
        guard packet.proto == .TCP else {
            return nil
        }

Close

Cognitive Complexity

Cognitive Complexity is a measure of how difficult a unit of code is to intuitively understand. Unlike Cyclomatic Complexity, which determines how difficult your code will be to test, Cognitive Complexity tells you how difficult your code will be to read and comprehend.

A method's cognitive complexity is based on a few simple rules:

• Code is not considered more complex when it uses shorthand that the language provides for collapsing multiple statements into one
• Code is considered more complex for each "break in the linear flow of the code"
• Code is considered more complex when "flow breaking structures are nested"

Further reading

• Cognitive Complexity docs
• Cognitive Complexity: A new way of measuring understandability

    func readAndProcessPackets() {
        NetworkInterface.TunnelProvider.packetFlow.readPacketsWithCompletionHandler() {
            var outputPackets = [IPMutablePacket]()
            let packets = $0.0.map { data in
                IPMutablePacket(payload: data)

Close

Cognitive Complexity

Cognitive Complexity is a measure of how difficult a unit of code is to intuitively understand. Unlike Cyclomatic Complexity, which determines how difficult your code will be to test, Cognitive Complexity tells you how difficult your code will be to read and comprehend.

A method's cognitive complexity is based on a few simple rules:

• Code is not considered more complex when it uses shorthand that the language provides for collapsing multiple statements into one
• Code is considered more complex for each "break in the linear flow of the code"
• Code is considered more complex when "flow breaking structures are nested"

Further reading

• Cognitive Complexity docs
• Cognitive Complexity: A new way of measuring understandability

    }

Close

function-whitespace

Every function and method declaration should have one blank line before and after itself. An exception to this rule are functions that are declared at the start of a file (only need one blank line after their declaration) or at the end of a file (only need one blank line before their declaration). Comments immediately before a function declaration (no blank lines between them and the function) are considered to be part of the declaration.

Preferred

func function1() {
  var text = 1
  var text = 2
}

function1()

// a comment
func function2() {
  // something goes here
}

struct SomeStruct {

  func function3() {
    // something goes here
  }

  func function4() {
    // something else goes here
  };

}

func function5() {
  // something goes here
}

Not Preferred

func function1() {
  var text = 1
  var text = 2
}
function1()
// a comment
func function2() {
  // something goes here
}

struct SomeStruct {
  func function3() {
    // something goes here
  }

  func function4() {
    // something else goes here
  };
}
func function5() {
  // something goes here
}

        NetworkInterface.TunnelProvider.packetFlow.readPacketsWithCompletionHandler() {

Close

redundant-parentheses

Control flow constructs (if, else if, switch, for, while, repeat-while, and guard statements), Exception handling constructs (throw, and do/catch statements), and Initializers (array, dictionary, initializer patterns) should not be enclosed in parentheses.

Additionally, method calls with no parameters and a trailing closure should not have empty parentheses following the method name.

Control flow constructs

• if, else if statement

Preferred

if SomeCondition {

} else if SomeOtherCondition {
}

Not Preferred

if (SomeCondition) {

} else if (SomeOtherCondition) {
}

• switch statement

Preferred

switch SomeData {
    default:
        break
}

Not Preferred

switch (SomeData) {
    default:
        break
}

• for loop

Preferred

for var i = 0; i < 10; i+=1 {

}

Not Preferred

for (var i = 0; i < 10; i+=1) {

}

• while loop

Preferred

while SomeCondition {

}

Not Preferred

while (SomeCondition) {

}

• repeat-while loop

Preferred

repeat {

} while SomeCondition

Not Preferred

repeat {

} while (SomeCondition)

• guard clause

Preferred

guard true else {   }

Not Preferred

guard (true) else {   }

Exception handling constructs

• do/catch statement

Preferred

do  {

} catch SomeException {

}

Not Preferred

do  {

} catch (SomeException) {

}

• throw statement

Preferred

throw SomeException

Not Preferred

throw (SomeException)

Initializers

• array items

Preferred

var shoppingList: [String] = ["Eggs", "Milk"]

Not Preferred

var shoppingList: [String] = [("Eggs"), ("Milk")]

• dictionary items

Preferred

var airports: [String: String] = ["YYZ": "Toronto Pearson", "DUB": "Dublin"]

Not Preferred

var airports: [String: String] = [("YYZ"): ("Toronto Pearson"), ("DUB"): ("Dublin")]

• initializer patterns

Preferred

var x: Int = 2
var y: String = "Sleekbyte"
var x = 2

Not Preferred

var x: Int = (2)
var y: String = ("Sleekbyte")
var x = (2)

Method calls

Preferred

items.map {
  item in item.transform()
}

Not Preferred

items.map() {
  item in item.transform()
}