SwiftLint/Source/SwiftLintFramework/Rules/Idiomatic/StaticOperatorRule.swift

103 lines
3.2 KiB
Swift

import Foundation
import SourceKittenFramework
public struct StaticOperatorRule: ASTRule, ConfigurationProviderRule, AutomaticTestableRule {
public var configuration = SeverityConfiguration(.warning)
public init() {}
public static let description = RuleDescription(
identifier: "static_operator",
name: "Static Operator",
description: "Operators should be declared as static functions, not free functions.",
kind: .idiomatic,
isOptIn: true,
nonTriggeringExamples: [
"""
class A: Equatable {
static func == (lhs: A, rhs: A) -> Bool {
return false
}
""",
"""
class A<T>: Equatable {
static func == <T>(lhs: A<T>, rhs: A<T>) -> Bool {
return false
}
""",
"""
public extension Array where Element == Rule {
static func == (lhs: Array, rhs: Array) -> Bool {
if lhs.count != rhs.count { return false }
return !zip(lhs, rhs).contains { !$0.0.isEqualTo($0.1) }
}
}
""",
"""
private extension Optional where Wrapped: Comparable {
static func < (lhs: Optional, rhs: Optional) -> Bool {
switch (lhs, rhs) {
case let (lhs?, rhs?):
return lhs < rhs
case (nil, _?):
return true
default:
return false
}
}
}
"""
],
triggeringExamples: [
"""
↓func == (lhs: A, rhs: A) -> Bool {
return false
}
""",
"""
↓func == <T>(lhs: A<T>, rhs: A<T>) -> Bool {
return false
}
""",
"""
↓func == (lhs: [Rule], rhs: [Rule]) -> Bool {
if lhs.count != rhs.count { return false }
return !zip(lhs, rhs).contains { !$0.0.isEqualTo($0.1) }
}
""",
"""
private ↓func < <T: Comparable>(lhs: T?, rhs: T?) -> Bool {
switch (lhs, rhs) {
case let (lhs?, rhs?):
return lhs < rhs
case (nil, _?):
return true
default:
return false
}
}
"""
]
)
public func validate(file: File, kind: SwiftDeclarationKind,
dictionary: [String: SourceKitRepresentable]) -> [StyleViolation] {
guard kind == .functionFree,
let offset = dictionary.offset,
let name = dictionary.name?.split(separator: "(").first.flatMap(String.init) else {
return []
}
let characterSet = CharacterSet(charactersIn: name)
guard characterSet.isDisjoint(with: .alphanumerics) else {
return []
}
return [
StyleViolation(ruleDescription: type(of: self).description,
severity: configuration.severity,
location: Location(file: file, byteOffset: offset))
]
}
}