SwiftLint/Source/SwiftLintFramework/Rules/Style/SwitchCaseOnNewlineRule.swift

87 lines
3.8 KiB
Swift

import Foundation
import SourceKittenFramework
private func wrapInSwitch(_ str: String) -> String {
return "switch foo {\n \(str)\n}\n"
}
public struct SwitchCaseOnNewlineRule: ASTRule, ConfigurationProviderRule, OptInRule, AutomaticTestableRule {
public var configuration = SeverityConfiguration(.warning)
public init() {}
public static let description = RuleDescription(
identifier: "switch_case_on_newline",
name: "Switch Case on Newline",
description: "Cases inside a switch should always be on a newline",
kind: .style,
nonTriggeringExamples: [
"/*case 1: */return true",
"//case 1:\n return true",
"let x = [caseKey: value]",
"let x = [key: .default]",
"if case let .someEnum(value) = aFunction([key: 2]) { }",
"guard case let .someEnum(value) = aFunction([key: 2]) { }",
"for case let .someEnum(value) = aFunction([key: 2]) { }",
"enum Environment {\n case development\n}",
"enum Environment {\n case development(url: URL)\n}",
"enum Environment {\n case development(url: URL) // staging\n}"
] + [
"case 1:\n return true",
"default:\n return true",
"case let value:\n return true",
"case .myCase: // error from network\n return true",
"case let .myCase(value) where value > 10:\n return false",
"case let .myCase(value)\n where value > 10:\n return false",
"case let .myCase(code: lhsErrorCode, description: _)\n where lhsErrorCode > 10:\n return false",
"case #selector(aFunction(_:)):\n return false\n"
].map(wrapInSwitch),
triggeringExamples: [
"↓case 1: return true",
"↓case let value: return true",
"↓default: return true",
"↓case \"a string\": return false",
"↓case .myCase: return false // error from network",
"↓case let .myCase(value) where value > 10: return false",
"↓case #selector(aFunction(_:)): return false\n",
"↓case let .myCase(value)\n where value > 10: return false",
"↓case .first,\n .second: return false"
].map(wrapInSwitch)
)
public func validate(file: SwiftLintFile, kind: StatementKind,
dictionary: SourceKittenDictionary) -> [StyleViolation] {
guard kind == .case,
let offset = dictionary.offset,
let length = dictionary.length,
let lastElement = dictionary.elements.last,
let lastElementOffset = lastElement.offset,
let lastElementLength = lastElement.length,
case let start = lastElementOffset + lastElementLength,
case let rangeLength = offset + length - start,
case let byteRange = NSRange(location: start, length: rangeLength),
let firstToken = firstNonCommentToken(inByteRange: byteRange, file: file),
let (tokenLine, _) = file.contents.bridge().lineAndCharacter(forByteOffset: firstToken.offset),
let (caseEndLine, _) = file.contents.bridge().lineAndCharacter(forByteOffset: start),
tokenLine == caseEndLine else {
return []
}
return [
StyleViolation(ruleDescription: type(of: self).description,
severity: configuration.severity,
location: Location(file: file, byteOffset: offset))
]
}
private func firstNonCommentToken(inByteRange byteRange: NSRange, file: SwiftLintFile) -> SwiftLintSyntaxToken? {
return file.syntaxMap.tokens(inByteRange: byteRange).first { token -> Bool in
guard let kind = token.kind else {
return false
}
return !SyntaxKind.commentKinds.contains(kind)
}
}
}