SwiftLint/Source/SwiftLintFramework/Rules/Idiomatic/ImplicitlyUnwrappedOptional...

70 lines
2.7 KiB
Swift

import Foundation
import SourceKittenFramework
public struct ImplicitlyUnwrappedOptionalRule: ASTRule, ConfigurationProviderRule, OptInRule {
public var configuration = ImplicitlyUnwrappedOptionalConfiguration(mode: .allExceptIBOutlets,
severity: SeverityConfiguration(.warning))
public init() {}
public static let description = RuleDescription(
identifier: "implicitly_unwrapped_optional",
name: "Implicitly Unwrapped Optional",
description: "Implicitly unwrapped optionals should be avoided when possible.",
kind: .idiomatic,
nonTriggeringExamples: [
Example("@IBOutlet private var label: UILabel!"),
Example("@IBOutlet var label: UILabel!"),
Example("@IBOutlet var label: [UILabel!]"),
Example("if !boolean {}"),
Example("let int: Int? = 42"),
Example("let int: Int? = nil")
],
triggeringExamples: [
Example("let label: UILabel!"),
Example("let IBOutlet: UILabel!"),
Example("let labels: [UILabel!]"),
Example("var ints: [Int!] = [42, nil, 42]"),
Example("let label: IBOutlet!"),
Example("let int: Int! = 42"),
Example("let int: Int! = nil"),
Example("var int: Int! = 42"),
Example("let int: ImplicitlyUnwrappedOptional<Int>"),
Example("let collection: AnyCollection<Int!>"),
Example("func foo(int: Int!) {}")
]
)
private func hasImplicitlyUnwrappedOptional(_ typeName: String) -> Bool {
return typeName.contains("!") || typeName.contains("ImplicitlyUnwrappedOptional<")
}
public func validate(file: SwiftLintFile, kind: SwiftDeclarationKind,
dictionary: SourceKittenDictionary) -> [StyleViolation] {
guard SwiftDeclarationKind.variableKinds.contains(kind) else {
return []
}
guard let typeName = dictionary.typeName else { return [] }
guard hasImplicitlyUnwrappedOptional(typeName) else { return [] }
if configuration.mode == .allExceptIBOutlets {
let isOutlet = dictionary.enclosedSwiftAttributes.contains(.iboutlet)
if isOutlet { return [] }
}
let location: Location
if let offset = dictionary.offset {
location = Location(file: file, byteOffset: offset)
} else {
location = Location(file: file.path)
}
return [
StyleViolation(ruleDescription: type(of: self).description,
severity: configuration.severity.severity,
location: location)
]
}
}