SwiftLint/Source/SwiftLintFramework/Rules/Lint/ClassDelegateProtocolRule.s...

92 lines
3.3 KiB
Swift

import Foundation
import SourceKittenFramework
public struct ClassDelegateProtocolRule: ASTRule, ConfigurationProviderRule, AutomaticTestableRule {
public var configuration = SeverityConfiguration(.warning)
public init() {}
public static let description = RuleDescription(
identifier: "class_delegate_protocol",
name: "Class Delegate Protocol",
description: "Delegate protocols should be class-only so they can be weakly referenced.",
kind: .lint,
nonTriggeringExamples: [
"protocol FooDelegate: class {}\n",
"protocol FooDelegate: class, BarDelegate {}\n",
"protocol Foo {}\n",
"class FooDelegate {}\n",
"@objc protocol FooDelegate {}\n",
"@objc(MyFooDelegate)\n protocol FooDelegate {}\n",
"protocol FooDelegate: BarDelegate {}\n",
"protocol FooDelegate: AnyObject {}\n",
"protocol FooDelegate: NSObjectProtocol {}\n"
],
triggeringExamples: [
"↓protocol FooDelegate {}\n",
"↓protocol FooDelegate: Bar {}\n"
]
)
private let referenceTypeProtocols: Set = ["AnyObject", "NSObjectProtocol", "class"]
public func validate(file: SwiftLintFile, kind: SwiftDeclarationKind,
dictionary: SourceKittenDictionary) -> [StyleViolation] {
guard kind == .protocol else {
return []
}
// Check if name contains "Delegate"
guard let name = dictionary.name, isDelegateProtocol(name) else {
return []
}
// Check if @objc
let objcAttributes: Set<SwiftDeclarationAttributeKind> = [.objc, .objcName]
let isObjc = !objcAttributes.isDisjoint(with: dictionary.enclosedSwiftAttributes)
guard !isObjc else {
return []
}
// Check if inherits from another Delegate protocol
guard !dictionary.inheritedTypes.contains(where: isDelegateProtocol) else {
return []
}
// Check if inherits from a known reference type protocol
guard !dictionary.inheritedTypes.contains(where: isReferenceTypeProtocol) else {
return []
}
// Check if : class
guard let offset = dictionary.offset,
let nameOffset = dictionary.nameOffset,
let nameLength = dictionary.nameLength,
let bodyOffset = dictionary.bodyOffset,
case let contents = file.stringView,
case let start = nameOffset + nameLength,
let range = contents.byteRangeToNSRange(start: start, length: bodyOffset - start),
!isClassProtocol(file: file, range: range) else {
return []
}
return [
StyleViolation(ruleDescription: type(of: self).description,
severity: configuration.severity,
location: Location(file: file, byteOffset: offset))
]
}
private func isClassProtocol(file: SwiftLintFile, range: NSRange) -> Bool {
return !file.match(pattern: "\\bclass\\b", with: [.keyword], range: range).isEmpty
}
private func isDelegateProtocol(_ name: String) -> Bool {
return name.hasSuffix("Delegate")
}
private func isReferenceTypeProtocol(_ name: String) -> Bool {
return referenceTypeProtocols.contains(name)
}
}