SwiftLint/Source/SwiftLintFramework/Rules/Idiomatic/RedundantNilCoalescingRule....

47 lines
1.8 KiB
Swift

import Foundation
import SourceKittenFramework
public struct RedundantNilCoalescingRule: OptInRule, SubstitutionCorrectableRule, ConfigurationProviderRule,
AutomaticTestableRule {
public var configuration = SeverityConfiguration(.warning)
public init() {}
public static let description = RuleDescription(
identifier: "redundant_nil_coalescing",
name: "Redundant Nil Coalescing",
description: "nil coalescing operator is only evaluated if the lhs is nil" +
", coalescing operator with nil as rhs is redundant",
kind: .idiomatic,
nonTriggeringExamples: [
Example("var myVar: Int?; myVar ?? 0\n")
],
triggeringExamples: [
Example("var myVar: Int? = nil; myVar↓ ?? nil\n"),
Example("var myVar: Int? = nil; myVar↓??nil\n")
],
corrections: [
Example("var myVar: Int? = nil; let foo = myVar↓ ?? nil\n"):
Example("var myVar: Int? = nil; let foo = myVar\n"),
Example("var myVar: Int? = nil; let foo = myVar↓??nil\n"):
Example("var myVar: Int? = nil; let foo = myVar\n")
]
)
public func validate(file: SwiftLintFile) -> [StyleViolation] {
return violationRanges(in: file).map {
StyleViolation(ruleDescription: type(of: self).description,
severity: configuration.severity,
location: Location(file: file, characterOffset: $0.location))
}
}
public func substitution(for violationRange: NSRange, in file: SwiftLintFile) -> (NSRange, String)? {
return (violationRange, "")
}
public func violationRanges(in file: SwiftLintFile) -> [NSRange] {
return file.match(pattern: "\\s?\\?{2}\\s*nil\\b", with: [.keyword])
}
}