use latest Swift snapshot

.gitmodules

@@ -15,7 +15,7 @@
 	url = https://github.com/jpsim/SourceKitten.git
 [submodule "Carthage/Checkouts/SwiftyTextTable"]
 	path = Carthage/Checkouts/SwiftyTextTable
-	url = https://github.com/scottrhoyt/SwiftyTextTable.git
+	url = https://github.com/jpsim/SwiftyTextTable.git
 [submodule "Carthage/Checkouts/Yams"]
 	path = Carthage/Checkouts/Yams
 	url = https://github.com/jpsim/Yams.git

Cartfile

@@ -1,2 +1,2 @@
-github "jpsim/SourceKitten" ~> 0.17
-github "scottrhoyt/SwiftyTextTable" ~> 0.5.0
+github "jpsim/SourceKitten" "jp-swift-4"
+github "jpsim/SwiftyTextTable" "jp-swift-4"

Cartfile.private

@@ -1,3 +1,3 @@
 github "Carthage/Commandant" "master"
 github "jspahrsummers/xcconfigs" "master"
-github "jpsim/Yams" ~> 0.3
+github "jpsim/Yams" "master"

Cartfile.resolved

@@ -1,7 +1,7 @@
 github "Carthage/Commandant" "16bcee12f48564c87bb13830f5320d21257e15b8"
-github "antitypical/Result" "3.2.2"
-github "drmohundro/SWXMLHash" "3.1.0"
-github "jpsim/SourceKitten" "0.17.6"
-github "jpsim/Yams" "0.3.2"
+github "antitypical/Result" "3.2.3"
+github "drmohundro/SWXMLHash" "4cb1b72d406b4309aed6e6b2f11f46aa83dacbf7"
+github "jpsim/SourceKitten" "6e60ee7d6e9885ad6e674d55a5f540b0e52def09"
+github "jpsim/SwiftyTextTable" "15f72002eea8e3b446d104d18225b6a828218d32"
+github "jpsim/Yams" "b53284ba4c8bdece9ec8aad2e0010602dac588e9"
 github "jspahrsummers/xcconfigs" "2055f18efbe18e77408f7f43947f7ad92b2d4ff0"
-github "scottrhoyt/SwiftyTextTable" "0.5.0"

Carthage/Checkouts/Result

@@ -1 +1 @@
-Subproject commit f460dee9c9de710463c91a505c1b4a566de7621c
+Subproject commit c8446185238659a2b27c0261f64ff1254291d07d

Carthage/Checkouts/SWXMLHash

@@ -1 +1 @@
-Subproject commit 10b0b412a39542d19d002d6ff9f00d1a158332d9
+Subproject commit 4cb1b72d406b4309aed6e6b2f11f46aa83dacbf7

Carthage/Checkouts/SourceKitten

@@ -1 +1 @@
-Subproject commit 91d9d5b20876da2afcbf34664bccc0bfd26088c7
+Subproject commit 6e60ee7d6e9885ad6e674d55a5f540b0e52def09

Carthage/Checkouts/SwiftyTextTable

@@ -1 +1 @@
-Subproject commit 13489587b932674addd93fdfca8e627a76e6a6db
+Subproject commit 15f72002eea8e3b446d104d18225b6a828218d32

Carthage/Checkouts/Yams

@@ -1 +1 @@
-Subproject commit acf403cb0d950a2d58ea8c63ce001deac2fde222
+Subproject commit b53284ba4c8bdece9ec8aad2e0010602dac588e9

Makefile

@@ -91,6 +91,9 @@ release: package archive portable_zip
 docker_test:
 	docker run -v `pwd`:`pwd` -w `pwd` --name swiftlint --rm norionomura/sourcekit:311 swift test
 
+docker_test_4:
+	docker run -v `pwd`:`pwd` -w `pwd` --name swiftlint --rm norionomura/swift:4020170524a swift test
+
 docker_htop:
 	docker run -it --rm --pid=container:swiftlint terencewestphal/htop || reset
 

Package.resolved

@@ -0,0 +1,79 @@
+{
+  "object": {
+    "pins": [
+      {
+        "package": "Clang_C",
+        "repositoryURL": "https://github.com/norio-nomura/Clang_C.git",
+        "state": {
+          "branch": null,
+          "revision": "90a9574276f0fd17f02f58979423c3fd4d73b59e",
+          "version": "1.0.2"
+        }
+      },
+      {
+        "package": "Commandant",
+        "repositoryURL": "https://github.com/Carthage/Commandant.git",
+        "state": {
+          "branch": null,
+          "revision": "c281992c31c3f41c48b5036c5a38185eaec32626",
+          "version": "0.12.0"
+        }
+      },
+      {
+        "package": "Result",
+        "repositoryURL": "https://github.com/antitypical/Result.git",
+        "state": {
+          "branch": null,
+          "revision": "c8446185238659a2b27c0261f64ff1254291d07d",
+          "version": "3.2.3"
+        }
+      },
+      {
+        "package": "SourceKit",
+        "repositoryURL": "https://github.com/norio-nomura/SourceKit.git",
+        "state": {
+          "branch": null,
+          "revision": "18eaa67ca44443bbe39646916792b9f0c98dbaa1",
+          "version": "1.0.1"
+        }
+      },
+      {
+        "package": "SourceKitten",
+        "repositoryURL": "https://github.com/jpsim/SourceKitten.git",
+        "state": {
+          "branch": "jp-swift-4",
+          "revision": "6632fb43284436ab77c709fb4c8c5e55de42f6f5",
+          "version": null
+        }
+      },
+      {
+        "package": "SwiftyTextTable",
+        "repositoryURL": "https://github.com/jpsim/SwiftyTextTable.git",
+        "state": {
+          "branch": "jp-swift-4",
+          "revision": "15f72002eea8e3b446d104d18225b6a828218d32",
+          "version": null
+        }
+      },
+      {
+        "package": "SWXMLHash",
+        "repositoryURL": "https://github.com/drmohundro/SWXMLHash.git",
+        "state": {
+          "branch": "version-4.0-changes",
+          "revision": "4cb1b72d406b4309aed6e6b2f11f46aa83dacbf7",
+          "version": null
+        }
+      },
+      {
+        "package": "Yams",
+        "repositoryURL": "https://github.com/jpsim/Yams.git",
+        "state": {
+          "branch": "master",
+          "revision": "b53284ba4c8bdece9ec8aad2e0010602dac588e9",
+          "version": null
+        }
+      }
+    ]
+  },
+  "version": 1
+}

Package.swift

@@ -1,17 +1,39 @@
+// swift-tools-version:4.0
 import PackageDescription
 
 let package = Package(
   name: "SwiftLint",
-  targets: [
-    Target(name: "SwiftLintFramework"),
-    Target(name: "swiftlint",
-      dependencies: [
-        .Target(name: "SwiftLintFramework")
-      ]),
+  products: [
+    .executable(name: "swiftlint", targets: ["swiftlint"]),
+    .library(name: "SwiftLintFramework", targets: ["SwiftLintFramework"])
   ],
   dependencies: [
-    .Package(url: "https://github.com/jpsim/SourceKitten.git", majorVersion: 0, minor: 17),
-    .Package(url: "https://github.com/jpsim/Yams.git", majorVersion: 0, minor: 3),
-    .Package(url: "https://github.com/scottrhoyt/SwiftyTextTable.git", majorVersion: 0, minor: 5),
-  ]
+    .package(url: "https://github.com/Carthage/Commandant.git", from: "0.12.0"),
+    .package(url: "https://github.com/jpsim/Yams.git", .branch("master")),
+    .package(url: "https://github.com/jpsim/SourceKitten.git", .branch("jp-swift-4")),
+    .package(url: "https://github.com/jpsim/SwiftyTextTable.git", .branch("jp-swift-4")),
+  ],
+  targets: [
+    .target(
+      name: "swiftlint",
+      dependencies: [
+        "Commandant",
+        "SwiftLintFramework",
+        "SwiftyTextTable"
+      ]
+    ),
+    .target(
+      name: "SwiftLintFramework",
+      dependencies: [
+        "SourceKittenFramework"
+      ]
+    ),
+    .testTarget(
+      name: "SwiftLintFrameworkTests",
+      dependencies: [
+        "SwiftLintFramework"
+      ]
+    )
+  ],
+  swiftLanguageVersions: [3, 4]
 )

Source/SwiftLintFramework/Extensions/Array+SwiftLint.swift

@@ -35,7 +35,7 @@ extension Array {
         return nil
     }
 
-    func group<U: Hashable>(by transform: (Element) -> U) -> [U: [Element]] {
+    func group<U>(by transform: (Element) -> U) -> [U: [Element]] {
         return reduce([:]) { dictionary, element in
             var dictionary = dictionary
             let key = transform(element)
@@ -52,11 +52,33 @@ extension Array {
     }
 
     func parallelFlatMap<T>(transform: @escaping ((Element) -> [T])) -> [T] {
-        return parallelMap(transform: transform).flatMap { $0 }
+        var result = [(Int, [T])]()
+        result.reserveCapacity(count)
+
+        let queueLabelPrefix = "io.realm.SwiftLintFramework.map.\(NSUUID().uuidString)"
+        let resultAccumulatorQueue = DispatchQueue(label: "\(queueLabelPrefix).resultAccumulator")
+        DispatchQueue.concurrentPerform(iterations: count) { index in
+            let jobIndexAndResults = (index, transform(self[index]))
+            resultAccumulatorQueue.sync {
+                result.append(jobIndexAndResults)
+            }
+        }
+        return result.sorted { $0.0 < $1.0 }.flatMap { $0.1 }
     }
 
     func parallelFlatMap<T>(transform: @escaping ((Element) -> T?)) -> [T] {
-        return parallelMap(transform: transform).flatMap { $0 }
+        var result = [(Int, T?)]()
+        result.reserveCapacity(count)
+
+        let queueLabelPrefix = "io.realm.SwiftLintFramework.map.\(NSUUID().uuidString)"
+        let resultAccumulatorQueue = DispatchQueue(label: "\(queueLabelPrefix).resultAccumulator")
+        DispatchQueue.concurrentPerform(iterations: count) { index in
+            let jobIndexAndResults = (index, transform(self[index]))
+            resultAccumulatorQueue.sync {
+                result.append(jobIndexAndResults)
+            }
+        }
+        return result.sorted { $0.0 < $1.0 }.flatMap { $0.1 }
     }
 
     func parallelMap<T>(transform: @escaping ((Element) -> T)) -> [T] {

Source/SwiftLintFramework/Extensions/File+SwiftLint.swift

@@ -100,8 +100,9 @@ extension File {
 
     internal func matchesAndSyntaxKinds(matching pattern: String,
                                         range: NSRange? = nil) -> [(NSTextCheckingResult, [SyntaxKind])] {
-        return matchesAndTokens(matching: pattern, range: range).map { textCheckingResult, tokens in
-            (textCheckingResult, tokens.flatMap { SyntaxKind(rawValue: $0.type) })
+        return matchesAndTokens(matching: pattern, range: range).map { textCheckingResultAndTokens in
+            let (textCheckingResult, tokens) = textCheckingResultAndTokens
+            return (textCheckingResult, tokens.flatMap { SyntaxKind(rawValue: $0.type) })
         }
     }
 
@@ -111,8 +112,9 @@ extension File {
     }
 
     internal func match(pattern: String, range: NSRange? = nil) -> [(NSRange, [SyntaxKind])] {
-        return matchesAndSyntaxKinds(matching: pattern, range: range).map { textCheckingResult, syntaxKinds in
-            (textCheckingResult.range, syntaxKinds)
+        return matchesAndSyntaxKinds(matching: pattern, range: range).map { textCheckingResultAndKinds in
+            let (textCheckingResult, syntaxKinds) = textCheckingResultAndKinds
+            return (textCheckingResult.range, syntaxKinds)
         }
     }
 
@@ -279,8 +281,10 @@ extension File {
     internal func correct<R: Rule>(legacyRule: R, patterns: [String: String]) -> [Correction] {
         typealias RangePatternTemplate = (NSRange, String, String)
         let matches: [RangePatternTemplate]
-        matches = patterns.flatMap({ pattern, template -> [RangePatternTemplate] in
-            return match(pattern: pattern).filter { range, kinds in
+        matches = patterns.flatMap({ arg -> [RangePatternTemplate] in
+            let (pattern, template) = arg
+            return match(pattern: pattern).filter { arg -> Bool in
+                let (range, kinds) = arg
                 return kinds.first == .identifier &&
                     !ruleEnabled(violatingRanges: [range], for: legacyRule).isEmpty
             }.map { ($0.0, pattern, template) }

Source/SwiftLintFramework/Extensions/NSRegularExpression+SwiftLint.swift

@@ -12,8 +12,10 @@ import Foundation
 #if !swift(>=3.1)
 public typealias NSRegularExpression = RegularExpression
 #endif
+#if !swift(>=4.0)
 public typealias NSTextCheckingResult = TextCheckingResult
 #endif
+#endif
 
 private var regexCache = [RegexCacheKey: NSRegularExpression]()
 private let regexCacheLock = NSLock()

Source/SwiftLintFramework/Models/Configuration.swift

@@ -294,12 +294,14 @@ private func warnAboutDeprecations(configurationDictionary dict: [String: Any],
     }
 
     // Deprecation warning for rules
-    let deprecatedRulesIdentifiers = ruleList.list.flatMap { (identifier, rule) -> [(String, String)] in
+    let deprecatedRulesIdentifiers = ruleList.list.flatMap { arg -> [(String, String)] in
+        let (identifier, rule) = arg
         return rule.description.deprecatedAliases.map { ($0, identifier) }
     }
 
     let userProvidedRuleIDs = Set(disabledRules + optInRules + whitelistRules)
-    let deprecatedUsages = deprecatedRulesIdentifiers.filter { deprecatedIdentifier, _ in
+    let deprecatedUsages = deprecatedRulesIdentifiers.filter { arg -> Bool in
+        let (deprecatedIdentifier, _) = arg
         return dict[deprecatedIdentifier] != nil || userProvidedRuleIDs.contains(deprecatedIdentifier)
     }
 

Source/SwiftLintFramework/Models/Linter.swift

@@ -36,12 +36,14 @@ extension Rule {
 
         let (disabledViolationsAndRegions, enabledViolationsAndRegions) = violations.map { violation in
             return (violation, regions.first(where: { $0.contains(violation.location) }))
-        }.partitioned { _, region in
-            return region?.isRuleEnabled(self) ?? true
+        }.partitioned { arg -> Bool in
+                let (_, region) = arg
+                return region?.isRuleEnabled(self) ?? true
         }
 
         let enabledViolations = enabledViolationsAndRegions.map { $0.0 }
-        let deprecatedToValidIDPairs = disabledViolationsAndRegions.flatMap { _, region -> [(String, String)] in
+        let deprecatedToValidIDPairs = disabledViolationsAndRegions.flatMap { arg -> [(String, String)] in
+            let (_, region) = arg
             let identifiers = region?.deprecatedAliasesDisabling(rule: self) ?? []
             return identifiers.map { ($0, type(of: self).description.identifier) }
         }

Source/SwiftLintFramework/Models/MasterRuleList.swift

@@ -67,8 +67,9 @@ public struct RuleList {
     }
 
     internal func allValidIdentifiers() -> [String] {
-        return list.flatMap { (_, rule) -> [String] in
-            rule.description.allIdentifiers
+        return list.flatMap { arg -> [String] in
+            let (_, rule) = arg
+            return rule.description.allIdentifiers
         }
     }
 }

Source/SwiftLintFramework/Models/RuleParameter.swift

@@ -18,6 +18,6 @@ public struct RuleParameter<T: Equatable>: Equatable {
 
 // MARK: - Equatable
 
-public func ==<T: Equatable>(lhs: RuleParameter<T>, rhs: RuleParameter<T>) -> Bool {
+public func ==<T> (lhs: RuleParameter<T>, rhs: RuleParameter<T>) -> Bool {
     return lhs.value == rhs.value && lhs.severity == rhs.severity
 }

Source/SwiftLintFramework/Protocols/Rule.swift

@@ -64,7 +64,7 @@ public extension ConfigurationProviderRule {
 
 public func == (lhs: [Rule], rhs: [Rule]) -> Bool {
     if lhs.count == rhs.count {
-        return zip(lhs, rhs).map { $0.isEqualTo($1) }.reduce(true) { $0 && $1 }
+        return zip(lhs, rhs).map { $0.0.isEqualTo($0.1) }.reduce(true) { $0 && $1 }
     }
 
     return false

Source/SwiftLintFramework/Reporters/CheckstyleReporter.swift

@@ -22,7 +22,7 @@ public struct CheckstyleReporter: Reporter {
             violations
                 .group(by: { ($0.location.file ?? "<nopath>").escapedForXML() })
                 .sorted(by: { $0.key < $1.key })
-                .map(generateForViolationFile).joined(),
+                .map({ generateForViolationFile($0.0, violations: $0.1) }).joined(),
             "\n</checkstyle>"
         ].joined()
     }

Source/SwiftLintFramework/Reporters/EmojiReporter.swift

@@ -20,7 +20,8 @@ public struct EmojiReporter: Reporter {
         return violations
             .group(by: { $0.location.file ?? "Other" })
             .sorted(by: { $0.key < $1.key })
-            .map(report).joined(separator: "\n")
+            .map({ report(for: $0.0, with: $0.1) })
+            .joined(separator: "\n")
     }
 
     private static func report(for file: String, with violations: [StyleViolation]) -> String {

Source/SwiftLintFramework/Rules/AttributesRule.swift

@@ -61,7 +61,8 @@ public struct AttributesRule: ASTRule, OptInRule, ConfigurationProviderRule {
 
     private func validateTestableImport(file: File) -> [StyleViolation] {
         let pattern = "@testable[\n]+\\s*import"
-        return file.match(pattern: pattern).flatMap { range, kinds -> StyleViolation? in
+        return file.match(pattern: pattern).flatMap { arg -> StyleViolation? in
+            let (range, kinds) = arg
             guard kinds == [.attributeBuiltin, .keyword] else {
                 return nil
             }
@@ -149,18 +150,20 @@ public struct AttributesRule: ASTRule, OptInRule, ConfigurationProviderRule {
                                                  attributesTokens: [(String, NSRange)],
                                                  line: Line, file: File) -> Set<String> {
         let attributesTokensWithParameters: [(String, Bool)] = attributesTokens.map {
-            let hasParameter = attributeContainsParameter(attributeRange: $1,
+            let hasParameter = attributeContainsParameter(attributeRange: $0.1,
                                                           line: line, file: file)
-            return ($0, hasParameter)
+            return ($0.0, hasParameter)
         }
         let allAttributes = previousAttributes + attributesTokensWithParameters
 
-        return Set(allAttributes.flatMap { (token, hasParameter) -> String? in
+        return Set(allAttributes.flatMap { arg -> String? in
             // an attribute should be on a new line if one of these is true:
             // 1. it's a parameterized attribute
             //      a. the parameter is on the token (i.e. warn_unused_result)
             //      b. the parameter was parsed in the `hasParameter` variable (most attributes)
             // 2. it's a whitelisted attribute, according to the current configuration
+
+            let (token, hasParameter) = arg
             let isParameterized = hasParameter || token.bridge().contains("(")
             if isParameterized || configuration.alwaysOnNewLine.contains(token) {
                 return token

Source/SwiftLintFramework/Rules/ColonRule.swift

@@ -195,14 +195,16 @@ extension ColonRule {
     fileprivate func typeColonViolationRanges(in file: File, matching pattern: String) -> [NSRange] {
         let nsstring = file.contents.bridge()
         let commentAndStringKindsSet = Set(SyntaxKind.commentAndStringKinds())
-        return file.rangesAndTokens(matching: pattern).filter { _, syntaxTokens in
+        return file.rangesAndTokens(matching: pattern).filter { arg in
+            let (_, syntaxTokens) = arg
             let syntaxKinds = syntaxTokens.flatMap { SyntaxKind(rawValue: $0.type) }
             if !syntaxKinds.starts(with: [.identifier, .typeidentifier]) {
                 return false
             }
             return Set(syntaxKinds).intersection(commentAndStringKindsSet).isEmpty
-        }.flatMap { range, syntaxTokens in
-            let identifierRange = nsstring
+        }.flatMap { arg in
+                let (range, syntaxTokens) = arg
+                let identifierRange = nsstring
                 .byteRangeToNSRange(start: syntaxTokens[0].offset, length: 0)
             return identifierRange.map { NSUnionRange($0, range) }
         }
@@ -281,10 +283,11 @@ extension ColonRule {
             return NSRange(location: offset, length: length)
         }
 
-        let even = ranges.enumerated().flatMap { $0 % 2 == 0 ? $1 : nil }
-        let odd = ranges.enumerated().flatMap { $0 % 2 != 0 ? $1 : nil }
+        let even = ranges.enumerated().flatMap { $0.0 % 2 == 0 ? $0.1 : nil }
+        let odd = ranges.enumerated().flatMap { $0.0 % 2 != 0 ? $0.1 : nil }
 
-        return zip(even, odd).map { evenRange, oddRange -> NSRange in
+        return zip(even, odd).map { evenOdd -> NSRange in
+            let (evenRange, oddRange) = evenOdd
             let location = NSMaxRange(evenRange)
             let length = oddRange.location - location
 

Source/SwiftLintFramework/Rules/ConditionalReturnsOnNewlineRule.swift

@@ -38,7 +38,8 @@ public struct ConditionalReturnsOnNewlineRule: ConfigurationProviderRule, Rule,
 
     public func validate(file: File) -> [StyleViolation] {
         let pattern = "(guard|if)[^\n]*return"
-        return file.rangesAndTokens(matching: pattern).filter { _, tokens in
+        return file.rangesAndTokens(matching: pattern).filter { arg in
+            let (_, tokens) = arg
             guard let firstToken = tokens.first, let lastToken = tokens.last,
                 SyntaxKind(rawValue: firstToken.type) == .keyword &&
                     SyntaxKind(rawValue: lastToken.type) == .keyword else {

Source/SwiftLintFramework/Rules/ControlStatementRule.swift

@@ -61,7 +61,8 @@ public struct ControlStatementRule: ConfigurationProviderRule {
             let pattern = statementKind == "guard"
                 ? "\(statementKind)\\s*\\([^,{]*\\)\\s*else\\s*\\{"
                 : "\(statementKind)\\s*\\([^,{]*\\)\\s*\\{"
-            return file.match(pattern: pattern).flatMap { match, syntaxKinds in
+            return file.match(pattern: pattern).flatMap { arg in
+                let (match, syntaxKinds) = arg
                 let matchString = file.contents.substring(from: match.location, length: match.length)
                 if isFalsePositive(matchString, syntaxKind: syntaxKinds.first) {
                     return nil

Source/SwiftLintFramework/Rules/EmptyEnumArgumentsRule.swift

@@ -67,7 +67,8 @@ public struct EmptyEnumArgumentsRule: ASTRule, ConfigurationProviderRule, Correc
                     return []
             }
 
-            return file.match(pattern: "\\([,\\s_]*\\)", range: caseRange).flatMap { range, kinds in
+            return file.match(pattern: "\\([,\\s_]*\\)", range: caseRange).flatMap { arg in
+                let (range, kinds) = arg
                 guard Set(kinds).isSubset(of: [.keyword]),
                     case let byteRange = NSRange(location: offset, length: length),
                     Set(file.syntaxMap.kinds(inByteRange: byteRange)) != [.keyword] else {

Source/SwiftLintFramework/Rules/FunctionParameterCountRule.swift

@@ -102,8 +102,14 @@ public struct FunctionParameterCountRule: ASTRule, ConfigurationProviderRule {
     }
 
     fileprivate func defaultFunctionParameterCount(file: File, byteOffset: Int, byteLength: Int) -> Int {
-        return file.contents.bridge().substringWithByteRange(start: byteOffset, length: byteLength)?
-            .characters.filter { $0 == "=" }.count ?? 0
+        guard let characters = file.contents.bridge().substringWithByteRange(start: byteOffset, length: byteLength)?
+            .characters else {
+                return 0
+        }
+        let equals: [Character] = characters.filter { char -> Bool in
+            return char == "="
+        }
+        return equals.count
     }
 
     fileprivate func functionIsInitializer(file: File, byteOffset: Int, byteLength: Int) -> Bool {

Source/SwiftLintFramework/Rules/GenericTypeNameRule.swift

@@ -77,7 +77,8 @@ public struct GenericTypeNameRule: ASTRule, ConfigurationProviderRule {
 
     private func validateGenericTypeAliases(in file: File) -> [StyleViolation] {
         let pattern = "typealias\\s+\\w+?\\s*" + genericTypePattern + "\\s*="
-        return file.match(pattern: pattern).flatMap { (range, tokens) -> [(String, Int)] in
+        return file.match(pattern: pattern).flatMap { arg -> [(String, Int)] in
+            let (range, tokens) = arg
             guard tokens.first == .keyword,
                 Set(tokens.dropFirst()) == [.identifier],
                 let match = genericTypeRegex.firstMatch(in: file.contents, options: [],
@@ -139,16 +140,19 @@ public struct GenericTypeNameRule: ASTRule, ConfigurationProviderRule {
             return []
         }
 
-        let namesAndRanges: [(String, NSRange)] = beforeWhere.split(separator: ",").flatMap { string, range in
-            return string.split(separator: ":").first.map {
-                let (trimmed, trimmedRange) = $0.0.trimmingWhitespaces()
-                return (trimmed, NSRange(location: range.location + trimmedRange.location,
-                                         length: trimmedRange.length))
+        let namesAndRanges: [(String, NSRange)] = beforeWhere.split(separator: ",")
+            .flatMap { arg -> (String, NSRange)? in
+                let (string, range) = arg
+                return string.split(separator: ":").first.map {
+                    let (trimmed, trimmedRange) = $0.0.trimmingWhitespaces()
+                    return (trimmed, NSRange(location: range.location + trimmedRange.location,
+                                             length: trimmedRange.length))
+                }
             }
-        }
 
         let contents = file.contents.bridge()
-        return namesAndRanges.flatMap { (name, range) -> (String, Int)? in
+        return namesAndRanges.flatMap { arg -> (String, Int)? in
+            let (name, range) = arg
             guard let byteRange = contents.NSRangeToByteRange(start: range.location + offset,
                                                               length: range.length),
                 file.syntaxMap.kinds(inByteRange: byteRange) == [.identifier] else {

Source/SwiftLintFramework/Rules/IdentifierNameRule.swift

@@ -37,13 +37,14 @@ public struct IdentifierNameRule: ASTRule, ConfigurationProviderRule {
             return []
         }
 
-        return validateName(dictionary: dictionary, kind: kind).map { name, offset in
+        return validateName(dictionary: dictionary, kind: kind).map { nameAndOffset in
+            let (name, offset) = nameAndOffset
             guard !configuration.excluded.contains(name) else {
                 return []
             }
 
             let isFunction = SwiftDeclarationKind.functionKinds().contains(kind)
-            let description = type(of: self).description
+            let description = Swift.type(of: self).description
 
             let type = self.type(for: kind)
             if !isFunction {
@@ -64,7 +65,7 @@ public struct IdentifierNameRule: ASTRule, ConfigurationProviderRule {
                         "\(configuration.minLengthThreshold) and " +
                         "\(configuration.maxLengthThreshold) characters long: '\(name)'"
                     return [
-                        StyleViolation(ruleDescription: type(of: self).description,
+                        StyleViolation(ruleDescription: Swift.type(of: self).description,
                                        severity: severity,
                                        location: Location(file: file, byteOffset: offset),
                                        reason: reason)

Source/SwiftLintFramework/Rules/ImplicitGetterRule.swift

@@ -54,7 +54,8 @@ public struct ImplicitGetterRule: ConfigurationProviderRule {
 
     public func validate(file: File) -> [StyleViolation] {
         let pattern = "\\bget\\b"
-        let getTokens: [SyntaxToken] = file.rangesAndTokens(matching: pattern).flatMap { _, tokens in
+        let getTokens: [SyntaxToken] = file.rangesAndTokens(matching: pattern).flatMap { arg in
+            let (_, tokens) = arg
             guard tokens.count == 1, let token = tokens.first,
                 SyntaxKind(rawValue: token.type) == .keyword else {
                 return nil

Source/SwiftLintFramework/Rules/ImplicitReturnRule.swift

@@ -68,7 +68,8 @@ public struct ImplicitReturnRule: ConfigurationProviderRule, CorrectableRule, Op
         let pattern = "(?:\\bin|\\{)\\s+(return\\s+)"
         let contents = file.contents.bridge()
 
-        return file.matchesAndSyntaxKinds(matching: pattern).flatMap { result, kinds in
+        return file.matchesAndSyntaxKinds(matching: pattern).flatMap { arg in
+            let (result, kinds) = arg
             let range = result.range
             guard kinds == [.keyword, .keyword] || kinds == [.keyword],
                 let byteRange = contents.NSRangeToByteRange(start: range.location,

Source/SwiftLintFramework/Rules/LargeTupleRule.swift

@@ -64,7 +64,8 @@ public struct LargeTupleRule: ASTRule, ConfigurationProviderRule {
         let offsets = violationOffsetsForTypes(in: file, dictionary: dictionary, kind: kind) +
             violationOffsetsForFunctions(in: file, dictionary: dictionary, kind: kind)
 
-        return offsets.flatMap { location, size in
+        return offsets.flatMap { arg in
+            let (location, size) = arg
             for parameter in configuration.params where size > parameter.value {
                 let reason = "Tuples should have at most \(configuration.warning) members."
                 return StyleViolation(ruleDescription: type(of: self).description,

Source/SwiftLintFramework/Rules/LegacyConstantRule.swift

@@ -45,7 +45,8 @@ public struct LegacyConstantRule: CorrectableRule, ConfigurationProviderRule {
 
     public func correct(file: File) -> [Correction] {
         var wordBoundPatterns: [String: String] = [:]
-        LegacyConstantRule.legacyPatterns.forEach { key, value in
+        LegacyConstantRule.legacyPatterns.forEach { arg in
+            let (key, value) = arg
             wordBoundPatterns["\\b" + key] = value
         }
 

Source/SwiftLintFramework/Rules/MarkRule.swift

@@ -150,10 +150,12 @@ public struct MarkRule: CorrectableRule, ConfigurationProviderRule {
 
     private func violationRanges(in file: File, matching pattern: String) -> [NSRange] {
         let nsstring = file.contents.bridge()
-        return file.rangesAndTokens(matching: pattern).filter { _, syntaxTokens in
+        return file.rangesAndTokens(matching: pattern).filter { arg -> Bool in
+            let (_, syntaxTokens) = arg
             return !syntaxTokens.isEmpty && SyntaxKind(rawValue: syntaxTokens[0].type) == .comment
-        }.flatMap { range, syntaxTokens in
-            let identifierRange = nsstring
+        }.flatMap { arg in
+                let (range, syntaxTokens) = arg
+                let identifierRange = nsstring
                 .byteRangeToNSRange(start: syntaxTokens[0].offset, length: 0)
             return identifierRange.map { NSUnionRange($0, range) }
         }

Source/SwiftLintFramework/Rules/NestingRule.swift

@@ -57,14 +57,17 @@ public struct NestingRule: ASTRule, ConfigurationProviderRule {
                     reason: "\(targetName) should be nested at most \(threshold) level\(pluralSuffix) deep"))
             }
         }
-        violations.append(contentsOf: dictionary.substructure.flatMap { subDict in
-            if let kind = (subDict.kind).flatMap(SwiftDeclarationKind.init) {
-                return (kind, subDict)
+        violations.append(contentsOf: dictionary.substructure
+            .flatMap { subDict -> [(SwiftDeclarationKind, [String: SourceKitRepresentable])] in
+                if let kind = (subDict.kind).flatMap(SwiftDeclarationKind.init) {
+                    return [(kind, subDict)]
+                }
+                return []
+            }.flatMap { kindAndSubdict -> [StyleViolation] in
+                let (kind, subDict) = kindAndSubdict
+                return validate(file: file, kind: kind, dictionary: subDict, level: level + 1)
             }
-            return nil
-        }.flatMap { kind, subDict in
-            return validate(file: file, kind: kind, dictionary: subDict, level: level + 1)
-        })
+        )
         return violations
     }
 }

Source/SwiftLintFramework/Rules/NimbleOperatorRule.swift

@@ -88,8 +88,9 @@ public struct NimbleOperatorRule: ConfigurationProviderRule, OptInRule, Correcta
         let excludingKinds = SyntaxKind.commentKinds()
 
         return file.match(pattern: pattern)
-            .filter { _, kinds in
-                kinds.filter(excludingKinds.contains).isEmpty && kinds.first == .identifier
+            .filter { arg -> Bool in
+                let (_, kinds) = arg
+                return kinds.filter(excludingKinds.contains).isEmpty && kinds.first == .identifier
             }.map { $0.0 }
     }
 

Source/SwiftLintFramework/Rules/NumberSeparatorRule.swift

@@ -24,7 +24,8 @@ public struct NumberSeparatorRule: OptInRule, CorrectableRule, ConfigurationProv
     )
 
     public func validate(file: File) -> [StyleViolation] {
-        return violatingRanges(in: file).map { range, _ in
+        return violatingRanges(in: file).map { rangeAndThing in
+            let (range, _) = rangeAndThing
             return StyleViolation(ruleDescription: type(of: self).description,
                                   severity: configuration.severityConfiguration.severity,
                                   location: Location(file: file, characterOffset: range.location))
@@ -86,7 +87,8 @@ public struct NumberSeparatorRule: OptInRule, CorrectableRule, ConfigurationProv
     }
 
     public func correct(file: File) -> [Correction] {
-        let violatingRanges = self.violatingRanges(in: file).filter { range, _ in
+        let violatingRanges = self.violatingRanges(in: file).filter { arg -> Bool in
+            let (range, _) = arg
             return !file.ruleEnabled(violatingRanges: [range], for: self).isEmpty
         }
 

Source/SwiftLintFramework/Rules/OpeningBraceRule.swift

@@ -101,7 +101,7 @@ public struct OpeningBraceRule: CorrectableRule, ConfigurationProviderRule {
         guard let indexRange = contents.nsrangeToIndexRange(violatingRange) else {
             return (contents, nil)
         }
-        let capturedString = contents[indexRange]
+        let capturedString = String(contents[indexRange])
         var adjustedRange = violatingRange
         var correctString = " {"
 

Source/SwiftLintFramework/Rules/OperatorFunctionWhitespaceRule.swift

@@ -40,9 +40,11 @@ public struct OperatorFunctionWhitespaceRule: ConfigurationProviderRule {
         let zeroOrManySpaces = "(\\s{0}|\\s{2,})"
         let pattern1 = "func\\s+[\(operators)]+\(zeroOrManySpaces)(<[A-Z]+>)?\\("
         let pattern2 = "func\(zeroOrManySpaces)[\(operators)]+\\s+(<[A-Z]+>)?\\("
-        return file.match(pattern: "(\(pattern1)|\(pattern2))").filter { _, syntaxKinds in
+        return file.match(pattern: "(\(pattern1)|\(pattern2))").filter { arg -> Bool in
+            let (_, syntaxKinds) = arg
             return syntaxKinds.first == .keyword
-        }.map { range, _ in
+        }.map { arg in
+            let (range, _) = arg
             return StyleViolation(ruleDescription: type(of: self).description,
                 severity: configuration.severity,
                 location: Location(file: file, characterOffset: range.location))

Source/SwiftLintFramework/Rules/OperatorUsageWhitespaceRule.swift

@@ -74,10 +74,11 @@ public struct OperatorUsageWhitespaceRule: OptInRule, CorrectableRule, Configura
     )
 
     public func validate(file: File) -> [StyleViolation] {
-        return violationRanges(file: file).map { range, _ in
-            StyleViolation(ruleDescription: type(of: self).description,
-                           severity: configuration.severity,
-                           location: Location(file: file, characterOffset: range.location))
+        return violationRanges(file: file).map { rangeAndString in
+            let (range, _) = rangeAndString
+            return StyleViolation(ruleDescription: type(of: self).description,
+                                  severity: configuration.severity,
+                                  location: Location(file: file, characterOffset: range.location))
         }
     }
 
@@ -98,8 +99,9 @@ public struct OperatorUsageWhitespaceRule: OptInRule, CorrectableRule, Configura
 
         let spaces = [(zeroSpaces, zeroSpaces), (oneSpace, manySpaces),
                       (manySpaces, oneSpace), (manySpaces, manySpaces)]
-        let patterns = spaces.map { first, second in
-            leadingVariableOrNumber + first + operators + second + trailingVariableOrNumber
+        let patterns = spaces.map { arg -> String in
+            let (first, second) = arg
+            return leadingVariableOrNumber + first + operators + second + trailingVariableOrNumber
         }
         let pattern = "(?:\(patterns.joined(separator: "|")))"
 
@@ -156,7 +158,8 @@ public struct OperatorUsageWhitespaceRule: OptInRule, CorrectableRule, Configura
     }
 
     public func correct(file: File) -> [Correction] {
-        let violatingRanges = violationRanges(file: file).filter { range, _ in
+        let violatingRanges = violationRanges(file: file).filter { arg -> Bool in
+            let (range, _) = arg
             return !file.ruleEnabled(violatingRanges: [range], for: self).isEmpty
         }
 

Source/SwiftLintFramework/Rules/SortedImportsRule.swift

@@ -43,7 +43,8 @@ public struct SortedImportsRule: ConfigurationProviderRule, OptInRule {
         }
 
         let modulePairs = zip(modulesAndOffsets, modulesAndOffsets.dropFirst())
-        let violatingOffsets = modulePairs.flatMap { previous, current in
+        let violatingOffsets = modulePairs.flatMap { arg -> Int? in
+            let (previous, current) = arg
             return current < previous ? current.1 : nil
         }
 

Source/SwiftLintFramework/Rules/StatementPositionRule.swift

@@ -107,7 +107,8 @@ private extension StatementPositionRule {
     }
 
     func defaultViolationRanges(in file: File, matching pattern: String) -> [NSRange] {
-        return file.match(pattern: pattern).filter { _, syntaxKinds in
+        return file.match(pattern: pattern).filter { arg -> Bool in
+            let (_, syntaxKinds) = arg
             return syntaxKinds.starts(with: [.keyword])
         }.flatMap { $0.0 }
     }

Source/SwiftLintFramework/Rules/TodoRule.swift

@@ -86,7 +86,8 @@ public struct TodoRule: ConfigurationProviderRule {
     }
 
     public func validate(file: File) -> [StyleViolation] {
-        return file.match(pattern: "\\b(?:TODO|FIXME)(?::|\\b)").flatMap { range, syntaxKinds in
+        return file.match(pattern: "\\b(?:TODO|FIXME)(?::|\\b)").flatMap { rangeAndKinds in
+            let (range, syntaxKinds) = rangeAndKinds
             if !syntaxKinds.filter({ !$0.isCommentLike }).isEmpty {
                 return nil
             }

Source/SwiftLintFramework/Rules/TypeNameRule.swift

@@ -48,7 +48,8 @@ public struct TypeNameRule: ASTRule, ConfigurationProviderRule {
 
     private func validateTypeAliasesAndAssociatedTypes(in file: File) -> [StyleViolation] {
         let rangesAndTokens = file.rangesAndTokens(matching: "(typealias|associatedtype)\\s+.+?\\b")
-        return rangesAndTokens.flatMap { _, tokens -> [StyleViolation] in
+        return rangesAndTokens.flatMap { arg -> [StyleViolation] in
+            let (_, tokens) = arg
             guard tokens.count == 2,
                 let keywordToken = tokens.first,
                 let nameToken = tokens.last,

Source/SwiftLintFramework/Rules/UnusedClosureParameterRule.swift

@@ -80,7 +80,8 @@ public struct UnusedClosureParameterRule: ASTRule, ConfigurationProviderRule, Co
 
     public func validate(file: File, kind: SwiftExpressionKind,
                          dictionary: [String: SourceKitRepresentable]) -> [StyleViolation] {
-        return violationRanges(in: file, dictionary: dictionary, kind: kind).map { range, name in
+        return violationRanges(in: file, dictionary: dictionary, kind: kind).map { rangeName in
+            let (range, name) = rangeName
             let reason = "Unused parameter \"\(name)\" in a closure should be replaced with _."
             return StyleViolation(ruleDescription: type(of: self).description,
                                   severity: configuration.severity,

Source/SwiftLintFramework/Rules/ValidIBInspectableRule.swift

@@ -115,7 +115,7 @@ public struct ValidIBInspectableRule: ASTRule, ConfigurationProviderRule {
             "NSRect"
         ]
 
-        let intTypes = ["", "8", "16", "32", "64"].flatMap { size in
+        let intTypes: [String] = ["", "8", "16", "32", "64"].flatMap { size in
             ["U", ""].flatMap { (sign: String) -> String in
                 "\(sign)Int\(size)"
             }

Source/swiftlint/Commands/AutoCorrectCommand.swift

@@ -37,7 +37,7 @@ struct AutoCorrectCommand: CommandProtocol {
             if !options.quiet {
                 queuedPrintError("Done correcting \(files.count) files!")
             }
-            return .success()
+            return .success(())
         }
     }
 }

Source/swiftlint/Commands/LintCommand.swift

@@ -33,7 +33,7 @@ struct LintCommand: CommandProtocol {
                 currentViolations = LintCommand.applyLeniency(options: options, violations: _currentViolations)
                 visitorMutationQueue.sync {
                     fileBenchmark.record(file: linter.file, from: start)
-                    currentRuleTimes.forEach { ruleBenchmark.record(id: $0, time: $1) }
+                    currentRuleTimes.forEach { ruleBenchmark.record(id: $0.0, time: $0.1) }
                     violations += currentViolations
                 }
             } else {
@@ -73,7 +73,7 @@ struct LintCommand: CommandProtocol {
         } else if strictWithViolations {
             exit(3)
         }
-        return .success()
+        return .success(())
     }
 
     private static func printStatus(violations: [StyleViolation], files: [File], serious: Int) {

Source/swiftlint/Commands/RulesCommand.swift

@@ -38,14 +38,14 @@ struct RulesCommand: CommandProtocol {
             }
 
             print(ruleDescription: rule.description)
-            return .success()
+            return .success(())
         }
 
         let configuration = Configuration(commandLinePath: options.configurationFile)
         let rules = ruleList(for: options, configuration: configuration)
 
         print(TextTable(ruleList: rules, configuration: configuration).render())
-        return .success()
+        return .success(())
     }
 
     private func ruleList(for options: RulesOptions, configuration: Configuration) -> RuleList {
@@ -53,7 +53,8 @@ struct RulesCommand: CommandProtocol {
             return masterRuleList
         }
 
-        let filtered: [Rule.Type] = masterRuleList.list.flatMap { ruleID, ruleType in
+        let filtered: [Rule.Type] = masterRuleList.list.flatMap { ruleIDAndType in
+            let (ruleID, ruleType) = ruleIDAndType
             let configuredRule = configuration.rules.first { rule in
                 return type(of: rule).description.identifier == ruleID
             }

Source/swiftlint/Commands/VersionCommand.swift

@@ -16,6 +16,6 @@ struct VersionCommand: CommandProtocol {
 
     func run(_ options: NoOptions<CommandantError<()>>) -> Result<(), CommandantError<()>> {
         print(Version.current.value)
-        return .success()
+        return .success(())
     }
 }

Source/swiftlint/Helpers/Benchmark.swift

@@ -38,7 +38,8 @@ struct Benchmark {
             return accu
         }
         let entriesKeyValues: [(String, Double)] = entriesDict.sorted { $0.1 < $1.1 }
-        let lines: [String] = entriesKeyValues.map { id, time -> String in
+        let lines: [String] = entriesKeyValues.map { idAndTime -> String in
+            let (id, time) = idAndTime
             return "\(numberFormatter.string(from: NSNumber(value: time))!): \(id)"
         }
         let string: String = lines.joined(separator: "\n") + "\n"

SwiftLint.xcodeproj/project.pbxproj

@@ -1492,7 +1492,7 @@
 				FRAMEWORK_VERSION = A;
 				INFOPLIST_FILE = "Source/SwiftLintFramework/Supporting Files/Info.plist";
 				LD_RUNPATH_SEARCH_PATHS = "@loader_path/Frameworks";
-				OTHER_SWIFT_FLAGS = "$(inherited) -Xfrontend -warn-long-function-bodies=150";
+				OTHER_SWIFT_FLAGS = "$(inherited)";
 				PRODUCT_BUNDLE_IDENTIFIER = "io.realm.$(PRODUCT_NAME:rfc1034identifier)";
 				PRODUCT_NAME = SwiftLintFramework;
 				SWIFT_VERSION = 3.0;
@@ -1574,7 +1574,7 @@
 				FRAMEWORK_VERSION = A;
 				INFOPLIST_FILE = "Source/SwiftLintFramework/Supporting Files/Info.plist";
 				LD_RUNPATH_SEARCH_PATHS = "@loader_path/Frameworks";
-				OTHER_SWIFT_FLAGS = "$(inherited) -Xfrontend -warn-long-function-bodies=150";
+				OTHER_SWIFT_FLAGS = "$(inherited)";
 				PRODUCT_BUNDLE_IDENTIFIER = "io.realm.$(PRODUCT_NAME:rfc1034identifier)";
 				PRODUCT_NAME = SwiftLintFramework;
 				SWIFT_VERSION = 3.0;
@@ -1620,7 +1620,7 @@
 				FRAMEWORK_VERSION = A;
 				INFOPLIST_FILE = "Source/SwiftLintFramework/Supporting Files/Info.plist";
 				LD_RUNPATH_SEARCH_PATHS = "@loader_path/Frameworks";
-				OTHER_SWIFT_FLAGS = "$(inherited) -Xfrontend -warn-long-function-bodies=150";
+				OTHER_SWIFT_FLAGS = "$(inherited)";
 				PRODUCT_BUNDLE_IDENTIFIER = "io.realm.$(PRODUCT_NAME:rfc1034identifier)";
 				PRODUCT_NAME = SwiftLintFramework;
 				SWIFT_VERSION = 3.0;

Tests/SwiftLintFrameworkTests/CustomRulesTests.swift

@@ -93,7 +93,7 @@ class CustomRulesTests: XCTestCase {
     func getCustomRules(_ extraConfig: [String:String] = [:]) -> (RegexConfiguration, CustomRules) {
         var config = ["regex": "pattern",
                       "match_kinds": "comment"]
-        extraConfig.forEach { config[$0] = $1 }
+        extraConfig.forEach { config[$0.0] = $0.1 }
 
         var regexConfig = RegexConfiguration(identifier: "custom")
         do {

Tests/SwiftLintFrameworkTests/TestHelpers.swift

@@ -191,7 +191,8 @@ extension XCTestCase {
         }
 
         // "disable" commands do not correct
-        ruleDescription.corrections.forEach { before, _ in
+        ruleDescription.corrections.forEach { arg in
+            let (before, _) = arg
             for command in disableCommands {
                 let beforeDisabled = command + before
                 let expectedCleaned = cleanedContentsAndMarkerOffsets(from: beforeDisabled).0