Changed RuleExample to be a struct

Source/SwiftLintFramework/ASTRule.swift

@@ -17,10 +17,10 @@ protocol ASTRule: Rule {
         dictionary: XPCDictionary) -> [StyleViolation]
 }
 
-public protocol RuleExample {
-    var ruleName: String { get }
-    var ruleDescription: String { get }
-    var correctExamples: [String] { get }
-    var failingExamples: [String] { get }
-    var showExamples: Bool { get }
+public struct RuleExample {
+    public let ruleName: String
+    public let ruleDescription: String
+    public let correctExamples: [String]
+    public let failingExamples: [String]
+    public let showExamples: Bool = true
 }

Source/SwiftLintFramework/Linter.swift

@@ -43,7 +43,7 @@ public struct Linter {
     }
 
     public var explainableRules: [RuleExample] {
-        return flatten(rules.map { $0 as? RuleExample })
+        return flatten(rules.map { $0.example })
     }
 
     /**

Source/SwiftLintFramework/Rule.swift

@@ -8,9 +8,10 @@
 
 import SourceKittenFramework
 
-protocol Validatable {
+public protocol Validatable {
     var identifier: String { get }
     func validateFile(file: File) -> [StyleViolation]
+    var example: RuleExample? { get }
 }
 
 protocol ParameterizedRule: Rule {

Source/SwiftLintFramework/Rules/ColonRule.swift

@@ -8,13 +8,13 @@
 
 import SourceKittenFramework
 
-public struct ColonRule: Rule, RuleExample {
+public struct ColonRule: Rule {
     let identifier = "colon"
 
     public init() {
     }
 
-    func validateFile(file: File) -> [StyleViolation] {
+    public func validateFile(file: File) -> [StyleViolation] {
         let pattern1 = file.matchPattern("\\w+\\s+:\\s*\\S+",
             withSyntaxKinds: [.Identifier, .Typeidentifier])
         let pattern2 = file.matchPattern("\\w+:(?:\\s{0}|\\s{2,})\\S+",
@@ -27,29 +27,25 @@ public struct ColonRule: Rule, RuleExample {
         }
     }
 
-    public var ruleName = "Colon Rule"
-
-    public var ruleDescription = "This rule checks whether you associate the colon with the identifier."
-
-    public var correctExamples = [
-        "let abc: Void\n",
-        "let abc: [Void: Void]\n",
-        "let abc: (Void, Void)\n",
-        "func abc(def: Void) {}\n"
-    ]
-
-    public var failingExamples = [
-        "let abc:Void\n",
-        "let abc:  Void\n",
-        "let abc :Void\n",
-        "let abc : Void\n",
-        "let abc : [Void: Void]\n",
-        "func abc(def:Void) {}\n",
-        "func abc(def:  Void) {}\n",
-        "func abc(def :Void) {}\n",
-        "func abc(def : Void) {}\n"
-    ]
-
-    public var showExamples = true
-
+    public let example: RuleExample? = RuleExample(
+        ruleName: "Colon Rule",
+        ruleDescription: "This rule checks whether you associate the colon with the identifier.",
+        correctExamples: [
+            "let abc: Void\n",
+            "let abc: [Void: Void]\n",
+            "let abc: (Void, Void)\n",
+            "func abc(def: Void) {}\n"
+        ],
+        failingExamples: [
+            "let abc:Void\n",
+            "let abc:  Void\n",
+            "let abc :Void\n",
+            "let abc : Void\n",
+            "let abc : [Void: Void]\n",
+            "func abc(def:Void) {}\n",
+            "func abc(def:  Void) {}\n",
+            "func abc(def :Void) {}\n",
+            "func abc(def : Void) {}\n"
+        ]
+    )
 }

Source/SwiftLintFramework/Rules/FileLengthRule.swift

@@ -31,4 +31,6 @@ struct FileLengthRule: ParameterizedRule {
         }
         return []
     }
+
+    let example: RuleExample? = nil
 }

Source/SwiftLintFramework/Rules/ForceCastRule.swift

@@ -8,12 +8,12 @@
 
 import SourceKittenFramework
 
-public struct ForceCastRule: Rule, RuleExample {
+public struct ForceCastRule: Rule {
     public init() { }
 
     let identifier = "force_cast"
 
-    func validateFile(file: File) -> [StyleViolation] {
+    public func validateFile(file: File) -> [StyleViolation] {
         return file.matchPattern("as!", withSyntaxKinds: [.Keyword]).map { range in
             return StyleViolation(type: .ForceCast,
                 location: Location(file: file, offset: range.location),
@@ -22,20 +22,14 @@ public struct ForceCastRule: Rule, RuleExample {
         }
     }
 
-    public var ruleName = "Force Cast Rule"
-
-    public var ruleDescription = "This rule checks whether you don't do force casts."
-
-    public var correctExamples = [
-        "NSNumber() as? Int\n",
-        "// NSNumber() as! Int\n",
-
-    ]
-
-    public var failingExamples = [
-        "NSNumber() as! Int\n"
-    ]
-
-    public var showExamples = true
+    public let example: RuleExample? = RuleExample(
+        ruleName: "Force Cast Rule",
+        ruleDescription: "This rule checks whether you don't do force casts.",
+        correctExamples: [
+            "NSNumber() as? Int\n",
+            "// NSNumber() as! Int\n",
+        ],
+        failingExamples: [ "NSNumber() as! Int\n" ]
+    )
 
 }

Source/SwiftLintFramework/Rules/FunctionBodyLengthRule.swift

@@ -77,4 +77,6 @@ struct FunctionBodyLengthRule: ASTRule, ParameterizedRule {
         }
         return []
     }
+
+    let example: RuleExample? = nil
 }

Source/SwiftLintFramework/Rules/LeadingWhitespaceRule.swift

@@ -24,4 +24,6 @@ struct LeadingWhitespaceRule: Rule {
         }
         return []
     }
+
+    let example: RuleExample? = nil
 }

Source/SwiftLintFramework/Rules/LineLengthRule.swift

@@ -32,4 +32,6 @@ struct LineLengthRule: ParameterizedRule {
             return nil
         })
     }
+
+    let example: RuleExample? = nil
 }

Source/SwiftLintFramework/Rules/NestingRule.swift

@@ -74,4 +74,6 @@ struct NestingRule: ASTRule {
         })
         return violations
     }
+
+    let example: RuleExample? = nil
 }

Source/SwiftLintFramework/Rules/TodoRule.swift

@@ -8,12 +8,12 @@
 
 import SourceKittenFramework
 
-public struct TodoRule: Rule, RuleExample {
+public struct TodoRule: Rule {
     let identifier = "todo"
 
     public init() { }
 
-    func validateFile(file: File) -> [StyleViolation] {
+    public func validateFile(file: File) -> [StyleViolation] {
         return file.matchPattern("// (TODO|FIXME):", withSyntaxKinds: [.Comment]).map { range in
             return StyleViolation(type: .TODO,
                 location: Location(file: file, offset: range.location),
@@ -22,22 +22,18 @@ public struct TodoRule: Rule, RuleExample {
         }
     }
 
-    public var ruleName = "Todo Rule"
-
-    public var ruleDescription = "This rule checks whether you removed all TODOs and FIXMEs."
-
-    public var correctExamples = [
-        "let string = \"// TODO:\"\n",
-        "let string = \"// FIXME:\"\n"
-    ]
-
-    public var failingExamples = [
-        "// TODO:\n",
-        "// FIXME:\n"
-    ]
-
-    public var showExamples = true
-
+    public let example: RuleExample? = RuleExample(
+        ruleName: "Todo Rule",
+        ruleDescription: "This rule checks whether you removed all TODOs and FIXMEs.",
+        correctExamples: [
+            "let string = \"// TODO:\"\n",
+            "let string = \"// FIXME:\"\n"
+        ],
+        failingExamples: [
+            "// TODO:\n",
+            "// FIXME:\n"
+        ]
+    )
 
 
 }

Source/SwiftLintFramework/Rules/TrailingNewlineRule.swift

@@ -24,4 +24,6 @@ struct TrailingNewlineRule: Rule {
         }
         return []
     }
+
+    let example: RuleExample? = nil
 }

Source/SwiftLintFramework/Rules/TrailingWhitespaceRule.swift

@@ -8,12 +8,12 @@
 
 import SourceKittenFramework
 
-public struct TrailingWhitespaceRule: Rule, RuleExample {
+public struct TrailingWhitespaceRule: Rule {
     public init() { }
 
     let identifier = "trailing_whitespace"
 
-    func validateFile(file: File) -> [StyleViolation] {
+    public func validateFile(file: File) -> [StyleViolation] {
         return file.contents.lines().map { line in
             (
                 index: line.index,
@@ -32,17 +32,10 @@ public struct TrailingWhitespaceRule: Rule, RuleExample {
         }
     }
 
-    public var ruleName = "Trailing Whitespace Rule"
-
-    public var ruleDescription = "This rule checks whether you don't have any trailing whitespace."
-
-    public var correctExamples = [
-        "//\n"
-    ]
-
-    public var failingExamples = [
-        "// \n"
-    ]
-
-    public var showExamples = false
+    public let example: RuleExample? = RuleExample(
+        ruleName: "Trailing Whitespace Rule",
+        ruleDescription: "This rule checks whether you don't have any trailing whitespace.",
+        correctExamples: [ "//\n" ],
+        failingExamples: [ "// \n" ]
+    )
 }

Source/SwiftLintFramework/Rules/TypeBodyLengthRule.swift

@@ -66,4 +66,6 @@ struct TypeBodyLengthRule: ASTRule, ParameterizedRule {
         }
         return []
     }
+
+    let example: RuleExample? = nil
 }

Source/SwiftLintFramework/Rules/TypeNameRule.swift

@@ -67,4 +67,6 @@ struct TypeNameRule: ASTRule {
         }
         return violations
     }
+
+    let example: RuleExample? = nil
 }

Source/SwiftLintFramework/Rules/VariableNameRule.swift

@@ -68,4 +68,6 @@ struct VariableNameRule: ASTRule {
         }
         return violations
     }
+
+    let example: RuleExample? = nil
 }

Source/SwiftLintFrameworkTests/LinterTests.swift

@@ -282,19 +282,19 @@ class LinterTests: XCTestCase {
     }
 
     func testLinesShouldntContainTrailingWhitespace() {
-        verifyRule(TrailingWhitespaceRule(), type: .TrailingWhitespace, violateInComments: true)
+        verifyRule(TrailingWhitespaceRule().example!, type: .TrailingWhitespace, violateInComments: true)
     }
 
     func testForceCasting() {
-        verifyRule(ForceCastRule(), type: .ForceCast)
+        verifyRule(ForceCastRule().example!, type: .ForceCast)
     }
 
     func testTodoOrFIXME() {
-        verifyRule(TodoRule(), type: .TODO)
+        verifyRule(TodoRule().example!, type: .TODO)
     }
 
     func testColon() {
-        verifyRule(ColonRule(), type: .Colon)
+        verifyRule(ColonRule().example!, type: .Colon)
     }
 
     func verifyRule(rule: RuleExample, type: StyleViolationType, violateInComments: Bool = false) {