Add Bool violation reporting in redundant_type_annotation

CHANGELOG.md

@@ -87,6 +87,10 @@
   `inclusive_language` rule, with a default value of `mastercard`.  
   [Dalton Claybrook](https://github.com/daltonclaybrook)
   [#3415](https://github.com/realm/SwiftLint/issues/3415)
+
+* Add Bool violation reporting in `redundant_type_annotation`.  
+  [Artem Garmash](https://github.com/agarmash)
+  [#3423](https://github.com/realm/SwiftLint/issues/3423)
 
 #### Bug Fixes
 

Source/SwiftLintFramework/Extensions/Configuration+FileGraph.swift

@@ -13,7 +13,7 @@ internal extension Configuration {
         private var vertices: Set<Vertix>
         private var edges: Set<Edge>
 
-        private var isBuilt: Bool = false
+        private var isBuilt = false
 
         // MARK: - Initializers
         internal init(commandLineChildConfigs: [String], rootDirectory: String, ignoreParentAndChildConfigs: Bool) {

Source/SwiftLintFramework/Extensions/Configuration+Remote.swift

@@ -70,7 +70,7 @@ internal extension Configuration.FileGraph.FilePath {
 
             // Load from url
             var taskResult: (Data?, URLResponse?, Error?)
-            var taskDone: Bool = false
+            var taskDone = false
 
             // `.ephemeral` disables caching (which we don't want to be managed by the system)
             let task = URLSession(configuration: .ephemeral).dataTask(with: url) { data, response, error in

Source/SwiftLintFramework/Models/Configuration.swift

@@ -38,7 +38,7 @@ public struct Configuration {
     /// This value is `true` iff the `--config` parameter was used to specify (a) configuration file(s)
     /// In particular, this means that the value is also `true` if the `--config` parameter
     /// was used to explicitly specify the default `.swiftlint.yml` as the configuration file
-    public private(set) var basedOnCustomConfigurationFiles: Bool = false
+    public private(set) var basedOnCustomConfigurationFiles = false
 
     // MARK: Public Computed
     /// All rules enabled in this configuration

Source/SwiftLintFramework/Rules/Idiomatic/RedundantTypeAnnotationRule.swift

@@ -5,8 +5,6 @@ public struct RedundantTypeAnnotationRule: OptInRule, SubstitutionCorrectableRul
                                            ConfigurationProviderRule, AutomaticTestableRule {
     public var configuration = SeverityConfiguration(.warning)
 
-    public init() {}
-
     public static let description = RuleDescription(
         identifier: "redundant_type_annotation",
         name: "Redundant Type Annotation",
@@ -15,7 +13,23 @@ public struct RedundantTypeAnnotationRule: OptInRule, SubstitutionCorrectableRul
         nonTriggeringExamples: [
             Example("var url = URL()"),
             Example("var url: CustomStringConvertible = URL()"),
-            Example("@IBInspectable var color: UIColor = UIColor.white")
+            Example("@IBInspectable var color: UIColor = UIColor.white"),
+            Example("""
+            enum Direction {
+                case up
+                case down
+            }
+
+            var direction: Direction = .up
+            """),
+            Example("""
+            enum Direction {
+                case up
+                case down
+            }
+
+            var direction = Direction.up
+            """)
         ],
         triggeringExamples: [
             Example("var url↓:URL=URL()"),
@@ -30,6 +44,15 @@ public struct RedundantTypeAnnotationRule: OptInRule, SubstitutionCorrectableRul
                 let myVar↓: Int = Int(5)
               }
             }
+            """),
+            Example("var isEnabled↓: Bool = true"),
+            Example("""
+            enum Direction {
+                case up
+                case down
+            }
+
+            var direction↓: Direction = Direction.up
             """)
         ],
         corrections: [
@@ -68,42 +91,81 @@ public struct RedundantTypeAnnotationRule: OptInRule, SubstitutionCorrectableRul
         return (violationRange, "")
     }
 
+    private let typeAnnotationPattern: String
+    private let expressionPattern: String
+
+    public init() {
+        typeAnnotationPattern =
+            ":\\s*" + // semicolon and any number of whitespaces
+            "\\w+"    // type name
+
+        expressionPattern =
+            "(var|let)" + // var or let
+            "\\s+" +      // at least single whitespace
+            "\\w+" +      // variable name
+            "\\s*" +      // possible whitespaces
+            typeAnnotationPattern +
+            "\\s*=\\s*" + // assignment operator with possible surrounding whitespaces
+            "\\w+" +      // assignee name (type or keyword)
+            "[\\(\\.]?"   // possible opening parenthesis or dot
+    }
+
     public func violationRanges(in file: SwiftLintFile) -> [NSRange] {
-        let typeAnnotationPattern = ":\\s?\\w+"
-        let pattern = "(var|let)\\s?\\w+\(typeAnnotationPattern)\\s?=\\s?\\w+(\\(|.)"
-        let foundRanges = file.match(pattern: pattern, with: [.keyword, .identifier, .typeidentifier, .identifier])
-        return foundRanges
-            .filter { !isFalsePositive(in: file, range: $0) && !isIBInspectable(range: $0, file: file) }
+        let violatingRanges = file
+            .match(pattern: expressionPattern)
+            .filter {
+                $0.1 == [.keyword, .identifier, .typeidentifier, .identifier] ||
+                $0.1 == [.keyword, .identifier, .typeidentifier, .keyword]
+            }
+            .filter { !isFalsePositive(file: file, range: $0.0) }
+            .filter { !isIBInspectable(file: file, range: $0.0) }
             .compactMap {
                 file.match(pattern: typeAnnotationPattern,
-                           excludingSyntaxKinds: SyntaxKind.commentAndStringKinds, range: $0).first
+                           excludingSyntaxKinds: SyntaxKind.commentAndStringKinds, range: $0.0).first
             }
+
+        return violatingRanges
     }
 
-    private func isFalsePositive(in file: SwiftLintFile, range: NSRange) -> Bool {
-        let substring = file.stringView.substring(with: range)
+    private func isFalsePositive(file: SwiftLintFile, range: NSRange) -> Bool {
+        guard let typeNames = getPartsOfExpression(in: file, range: range) else { return false }
+
+        let lhs = typeNames.variableTypeName
+        let rhs = typeNames.assigneeName
+
+        if lhs == rhs || (lhs == "Bool" && (rhs == "true" || rhs == "false")) {
+            return false
+        } else {
+            return true
+        }
+    }
 
+    private func getPartsOfExpression(
+        in file: SwiftLintFile, range: NSRange
+    ) -> (variableTypeName: String, assigneeName: String)? {
+        let substring = file.stringView.substring(with: range)
         let components = substring.components(separatedBy: "=")
-        let charactersToTrimFromRhs = CharacterSet(charactersIn: ".(").union(.whitespaces)
 
         guard
             components.count == 2,
-            let lhsTypeName = components[0].components(separatedBy: ":").last?.trimmingCharacters(in: .whitespaces)
+            let variableTypeName = components[0].components(separatedBy: ":").last?.trimmingCharacters(in: .whitespaces)
         else {
-            return true
+            return nil
         }
 
-        let rhsTypeName = components[1].trimmingCharacters(in: charactersToTrimFromRhs)
-        return lhsTypeName != rhsTypeName
+        let charactersToTrimFromRhs = CharacterSet(charactersIn: ".(").union(.whitespaces)
+        let assigneeName = components[1].trimmingCharacters(in: charactersToTrimFromRhs)
+
+        return (variableTypeName, assigneeName)
     }
 
-    private func isIBInspectable(range: NSRange, file: SwiftLintFile) -> Bool {
-        guard let byteRange = file.stringView.NSRangeToByteRange(start: range.location, length: range.length),
+    private func isIBInspectable(file: SwiftLintFile, range: NSRange) -> Bool {
+        guard
+            let byteRange = file.stringView.NSRangeToByteRange(start: range.location, length: range.length),
             let dict = file.structureDictionary.structures(forByteOffset: byteRange.location).last,
             let kind = dict.declarationKind,
-            SwiftDeclarationKind.variableKinds.contains(kind) else {
-                return false
-        }
+            SwiftDeclarationKind.variableKinds.contains(kind)
+        else { return false }
 
         return dict.enclosedSwiftAttributes.contains(.ibinspectable)
     }

Source/SwiftLintFramework/Rules/RuleConfigurations/EmptyCountConfiguration.swift

@@ -5,7 +5,7 @@ private enum ConfigurationKey: String {
 
 public struct EmptyCountConfiguration: RuleConfiguration, Equatable {
     private(set) var severityConfiguration = SeverityConfiguration(.error)
-    private(set) var onlyAfterDot: Bool = false
+    private(set) var onlyAfterDot = false
 
     public var consoleDescription: String {
         return [severityConfiguration.consoleDescription,

Source/SwiftLintFramework/Rules/RuleConfigurations/OpeningBraceConfiguration.swift

@@ -5,7 +5,7 @@ private enum ConfigurationKey: String {
 
 public struct OpeningBraceConfiguration: RuleConfiguration, Equatable {
     private(set) var severityConfiguration = SeverityConfiguration(.warning)
-    private(set) var allowMultilineFunc: Bool = false
+    private(set) var allowMultilineFunc = false
 
     public var consoleDescription: String {
         return [severityConfiguration.consoleDescription,