Require visitors to exist (#4383)

Source/SwiftLintFramework/Protocols/SwiftSyntaxRule.swift

@@ -7,7 +7,7 @@ public protocol SwiftSyntaxRule: SourceKitFreeRule {
     /// - parameter file: The file for which to produce the visitor.
     ///
     /// - returns: A `ViolationsSyntaxVisitor` for the given file.
-    func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor?
+    func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor
 
     /// Produce a violation for the given file and absolute position.
     ///
@@ -53,12 +53,11 @@ public extension SwiftSyntaxRule {
     }
 
     func validate(file: SwiftLintFile) -> [StyleViolation] {
-        guard let visitor = makeVisitor(file: file),
-              let syntaxTree = preprocess(syntaxTree: file.syntaxTree) else {
+        guard let syntaxTree = preprocess(syntaxTree: file.syntaxTree) else {
             return []
         }
 
-        return visitor
+        return makeVisitor(file: file)
             .walk(tree: syntaxTree, handler: \.violations)
             .sorted()
             .map { makeViolation(file: file, violation: $0) }

Source/SwiftLintFramework/Rules/Idiomatic/AnonymousArgumentInMultilineClosureRule.swift

@@ -33,7 +33,7 @@ public struct AnonymousArgumentInMultilineClosureRule: SwiftSyntaxRule, OptInRul
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(locationConverter: file.locationConverter)
     }
 }

Source/SwiftLintFramework/Rules/Idiomatic/BlockBasedKVORule.swift

@@ -35,7 +35,7 @@ public struct BlockBasedKVORule: SwiftSyntaxRule, ConfigurationProviderRule {
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Idiomatic/DiscouragedAssertRule.swift

@@ -31,7 +31,7 @@ public struct DiscouragedAssertRule: SwiftSyntaxRule, OptInRule, ConfigurationPr
 
     // MARK: - Public
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Idiomatic/DiscouragedObjectLiteralRule.swift

@@ -24,7 +24,7 @@ public struct DiscouragedObjectLiteralRule: SwiftSyntaxRule, OptInRule, Configur
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(configuration: configuration)
     }
 }

Source/SwiftLintFramework/Rules/Idiomatic/DiscouragedOptionalBooleanRule.swift

@@ -14,7 +14,7 @@ public struct DiscouragedOptionalBooleanRule: OptInRule, ConfigurationProviderRu
         triggeringExamples: DiscouragedOptionalBooleanRuleExamples.triggeringExamples
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Idiomatic/ExplicitEnumRawValueRule.swift

@@ -79,7 +79,7 @@ public struct ExplicitEnumRawValueRule: SwiftSyntaxRule, OptInRule, Configuratio
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Idiomatic/ExplicitInitRule.swift

@@ -171,7 +171,7 @@ public struct ExplicitInitRule: SwiftSyntaxCorrectableRule, ConfigurationProvide
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 

Source/SwiftLintFramework/Rules/Idiomatic/FallthroughRule.swift

@@ -30,7 +30,7 @@ public struct FallthroughRule: SwiftSyntaxRule, ConfigurationProviderRule, OptIn
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Idiomatic/ForceCastRule.swift

@@ -16,7 +16,7 @@ public struct ForceCastRule: ConfigurationProviderRule, SwiftSyntaxRule {
         triggeringExamples: [ Example("NSNumber() ↓as! Int\n") ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         ForceCastRuleVisitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Idiomatic/ForceTryRule.swift

@@ -26,7 +26,7 @@ public struct ForceTryRule: ConfigurationProviderRule, SwiftSyntaxRule {
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Idiomatic/ForceUnwrappingRule.swift

@@ -67,7 +67,7 @@ public struct ForceUnwrappingRule: OptInRule, SwiftSyntaxRule, ConfigurationProv
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         ForceUnwrappingVisitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Idiomatic/FunctionDefaultParameterAtEndRule.swift

@@ -51,7 +51,7 @@ public struct FunctionDefaultParameterAtEndRule: SwiftSyntaxRule, ConfigurationP
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Idiomatic/IsDisjointRule.swift

@@ -22,7 +22,7 @@ public struct IsDisjointRule: SwiftSyntaxRule, ConfigurationProviderRule {
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Idiomatic/LegacyCGGeometryFunctionsRule.swift

@@ -102,7 +102,7 @@ public struct LegacyCGGeometryFunctionsRule: SwiftSyntaxCorrectableRule, Configu
         "CGRectIntersection": .function(name: "intersect", argumentLabels: [""])
     ]
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         LegacyFunctionRuleHelper.Visitor(legacyFunctions: Self.legacyFunctions)
     }
 

Source/SwiftLintFramework/Rules/Idiomatic/LegacyConstantRule.swift

@@ -16,7 +16,7 @@ public struct LegacyConstantRule: SwiftSyntaxCorrectableRule, ConfigurationProvi
         corrections: LegacyConstantRuleExamples.corrections
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 

Source/SwiftLintFramework/Rules/Idiomatic/LegacyHashingRule.swift

@@ -75,7 +75,7 @@ public struct LegacyHashingRule: SwiftSyntaxRule, ConfigurationProviderRule {
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Idiomatic/LegacyMultipleRule.swift

@@ -43,7 +43,7 @@ public struct LegacyMultipleRule: OptInRule, ConfigurationProviderRule, SwiftSyn
         syntaxTree.folded()
     }
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Idiomatic/LegacyNSGeometryFunctionsRule.swift

@@ -102,7 +102,7 @@ public struct LegacyNSGeometryFunctionsRule: SwiftSyntaxCorrectableRule, Configu
         "NSPointInRect": .function(name: "contains", argumentLabels: [""], reversed: true)
     ]
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         LegacyFunctionRuleHelper.Visitor(legacyFunctions: Self.legacyFunctions)
     }
 

Source/SwiftLintFramework/Rules/Idiomatic/LegacyRandomRule.swift

@@ -22,7 +22,7 @@ public struct LegacyRandomRule: SwiftSyntaxRule, ConfigurationProviderRule {
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Idiomatic/NoExtensionAccessModifierRule.swift

@@ -23,7 +23,7 @@ public struct NoExtensionAccessModifierRule: SwiftSyntaxRule, OptInRule, Configu
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Idiomatic/NoFallthroughOnlyRule.swift

@@ -14,7 +14,7 @@ public struct NoFallthroughOnlyRule: SwiftSyntaxRule, ConfigurationProviderRule
         triggeringExamples: NoFallthroughOnlyRuleExamples.triggeringExamples
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Idiomatic/PrivateOverFilePrivateRule.swift

@@ -56,7 +56,7 @@ public struct PrivateOverFilePrivateRule: ConfigurationProviderRule, SwiftSyntax
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(validateExtensions: configuration.validateExtensions)
     }
 

Source/SwiftLintFramework/Rules/Idiomatic/RedundantNilCoalescingRule.swift

@@ -23,7 +23,7 @@ public struct RedundantNilCoalescingRule: OptInRule, SwiftSyntaxCorrectableRule,
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 

Source/SwiftLintFramework/Rules/Idiomatic/RedundantStringEnumValueRule.swift

@@ -61,7 +61,7 @@ public struct RedundantStringEnumValueRule: SwiftSyntaxRule, ConfigurationProvid
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Idiomatic/ReturnValueFromVoidFunctionRule.swift

@@ -15,7 +15,7 @@ public struct ReturnValueFromVoidFunctionRule: ConfigurationProviderRule, OptInR
         triggeringExamples: ReturnValueFromVoidFunctionRuleExamples.triggeringExamples
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         ReturnValueFromVoidFunctionVisitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Idiomatic/ShorthandOptionalBindingRule.swift

@@ -81,7 +81,7 @@ public struct ShorthandOptionalBindingRule: OptInRule, SwiftSyntaxCorrectableRul
 
     public init() {}
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 

Source/SwiftLintFramework/Rules/Idiomatic/StaticOperatorRule.swift

@@ -78,7 +78,7 @@ public struct StaticOperatorRule: SwiftSyntaxRule, ConfigurationProviderRule, Op
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Idiomatic/StrictFilePrivateRule.swift

@@ -58,7 +58,7 @@ public struct StrictFilePrivateRule: OptInRule, ConfigurationProviderRule, Swift
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Idiomatic/ToggleBoolRule.swift

@@ -31,7 +31,7 @@ public struct ToggleBoolRule: SwiftSyntaxCorrectableRule, ConfigurationProviderR
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 

Source/SwiftLintFramework/Rules/Idiomatic/TrailingSemicolonRule.swift

@@ -24,7 +24,7 @@ public struct TrailingSemicolonRule: SwiftSyntaxCorrectableRule, ConfigurationPr
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 

Source/SwiftLintFramework/Rules/Idiomatic/UnavailableConditionRule.swift

@@ -71,7 +71,7 @@ public struct UnavailableConditionRule: ConfigurationProviderRule, SwiftSyntaxRu
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         UnavailableConditionRuleVisitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Idiomatic/UnneededBreakInSwitchRule.swift

@@ -50,7 +50,7 @@ public struct UnneededBreakInSwitchRule: SwiftSyntaxRule, ConfigurationProviderR
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         UnneededBreakInSwitchRuleVisitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Idiomatic/UntypedErrorInCatchRule.swift

@@ -87,7 +87,7 @@ public struct UntypedErrorInCatchRule: OptInRule, ConfigurationProviderRule, Swi
             Example("do {\n    try foo() \n} ↓catch (let error) {}"): Example("do {\n    try foo() \n} catch {}")
         ])
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         UntypedErrorInCatchRuleVisitor(viewMode: .sourceAccurate)
     }
 

Source/SwiftLintFramework/Rules/Idiomatic/VoidFunctionInTernaryConditionRule.swift

@@ -108,7 +108,7 @@ public struct VoidFunctionInTernaryConditionRule: ConfigurationProviderRule, Swi
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         VoidFunctionInTernaryConditionVisitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Idiomatic/XCTFailMessageRule.swift

@@ -36,7 +36,7 @@ public struct XCTFailMessageRule: SwiftSyntaxRule, ConfigurationProviderRule {
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Lint/AnyObjectProtocolRule.swift

@@ -42,7 +42,7 @@ public struct AnyObjectProtocolRule: SwiftSyntaxCorrectableRule, OptInRule, Conf
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         warnDeprecatedOnce()
         return Visitor(viewMode: .sourceAccurate)
     }

Source/SwiftLintFramework/Rules/Lint/ArrayInitRule.swift

@@ -51,7 +51,7 @@ public struct ArrayInitRule: SwiftSyntaxRule, ConfigurationProviderRule, OptInRu
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Lint/ClassDelegateProtocolRule.swift

@@ -31,7 +31,7 @@ public struct ClassDelegateProtocolRule: SwiftSyntaxRule, ConfigurationProviderR
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Lint/DeploymentTargetRule.swift

@@ -16,7 +16,7 @@ public struct DeploymentTargetRule: ConfigurationProviderRule, SwiftSyntaxRule {
         triggeringExamples: DeploymentTargetRuleExamples.triggeringExamples
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(platformToConfiguredMinVersion: platformToConfiguredMinVersion)
     }
 

Source/SwiftLintFramework/Rules/Lint/DuplicateEnumCasesRule.swift

@@ -37,7 +37,7 @@ public struct DuplicateEnumCasesRule: ConfigurationProviderRule, SwiftSyntaxRule
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Lint/DynamicInlineRule.swift

@@ -24,7 +24,7 @@ public struct DynamicInlineRule: SwiftSyntaxRule, ConfigurationProviderRule {
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Lint/EmptyXCTestMethodRule.swift

@@ -14,7 +14,7 @@ public struct EmptyXCTestMethodRule: OptInRule, ConfigurationProviderRule, Swift
         triggeringExamples: EmptyXCTestMethodRuleExamples.triggeringExamples
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         EmptyXCTestMethodRuleVisitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Lint/IBInspectableInExtensionRule.swift

@@ -26,7 +26,7 @@ public struct IBInspectableInExtensionRule: SwiftSyntaxRule, ConfigurationProvid
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Lint/IdenticalOperandsRule.swift

@@ -75,7 +75,7 @@ public struct IdenticalOperandsRule: ConfigurationProviderRule, SwiftSyntaxRule,
         syntaxTree.folded()
     }
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Lint/InertDeferRule.swift

@@ -50,7 +50,7 @@ public struct InertDeferRule: ConfigurationProviderRule, SwiftSyntaxRule {
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Lint/NSLocalizedStringRequireBundleRule.swift

@@ -42,7 +42,7 @@ public struct NSLocalizedStringRequireBundleRule: SwiftSyntaxRule, OptInRule, Co
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Lint/NSObjectPreferIsEqualRule.swift

@@ -14,7 +14,7 @@ public struct NSObjectPreferIsEqualRule: SwiftSyntaxRule, ConfigurationProviderR
         triggeringExamples: NSObjectPreferIsEqualRuleExamples.triggeringExamples
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Lint/PrivateActionRule.swift

@@ -33,7 +33,7 @@ public struct PrivateActionRule: SwiftSyntaxRule, OptInRule, ConfigurationProvid
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Lint/PrivateOutletRule.swift

@@ -78,7 +78,7 @@ public struct PrivateOutletRule: SwiftSyntaxRule, OptInRule, ConfigurationProvid
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(allowPrivateSet: configuration.allowPrivateSet)
     }
 }

Source/SwiftLintFramework/Rules/Lint/PrivateUnitTestRule.swift

@@ -136,7 +136,7 @@ public struct PrivateUnitTestRule: SwiftSyntaxCorrectableRule, ConfigurationProv
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(parentClassRegex: configuration.regex)
     }
 

Source/SwiftLintFramework/Rules/Lint/ProhibitedInterfaceBuilderRule.swift

@@ -20,7 +20,7 @@ public struct ProhibitedInterfaceBuilderRule: ConfigurationProviderRule, SwiftSy
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Lint/QuickDiscouragedFocusedTestRule.swift

@@ -14,7 +14,7 @@ public struct QuickDiscouragedFocusedTestRule: OptInRule, ConfigurationProviderR
         triggeringExamples: QuickDiscouragedFocusedTestRuleExamples.triggeringExamples
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Lint/QuickDiscouragedPendingTestRule.swift

@@ -14,7 +14,7 @@ public struct QuickDiscouragedPendingTestRule: OptInRule, ConfigurationProviderR
         triggeringExamples: QuickDiscouragedPendingTestRuleExamples.triggeringExamples
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Lint/SelfInPropertyInitializationRule.swift

@@ -92,7 +92,7 @@ public struct SelfInPropertyInitializationRule: ConfigurationProviderRule, Swift
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Lint/StrongIBOutletRule.swift

@@ -29,7 +29,7 @@ public struct StrongIBOutletRule: ConfigurationProviderRule, SwiftSyntaxCorrecta
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 

Source/SwiftLintFramework/Rules/Lint/UnownedVariableCaptureRule.swift

@@ -25,7 +25,7 @@ public struct UnownedVariableCaptureRule: SwiftSyntaxRule, OptInRule, Configurat
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         UnownedVariableCaptureRuleVisitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Lint/UnusedClosureParameterRule.swift

@@ -16,7 +16,7 @@ public struct UnusedClosureParameterRule: SwiftSyntaxCorrectableRule, Configurat
         corrections: UnusedClosureParameterRuleExamples.corrections
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 

Source/SwiftLintFramework/Rules/Lint/UnusedSetterValueRule.swift

@@ -129,7 +129,7 @@ public struct UnusedSetterValueRule: ConfigurationProviderRule, SwiftSyntaxRule
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Lint/ValidIBInspectableRule.swift

@@ -110,7 +110,7 @@ public struct ValidIBInspectableRule: SwiftSyntaxRule, ConfigurationProviderRule
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 

Source/SwiftLintFramework/Rules/Lint/YodaConditionRule.swift

@@ -36,7 +36,7 @@ public struct YodaConditionRule: OptInRule, ConfigurationProviderRule, SwiftSynt
             Example("if ↓200 <= i && i <= 299 || ↓600 <= i {}")
         ])
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         YodaConditionRuleVisitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Performance/ContainsOverFilterCountRule.swift

@@ -30,7 +30,7 @@ public struct ContainsOverFilterCountRule: SwiftSyntaxRule, OptInRule, Configura
         }
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Performance/ContainsOverFilterIsEmptyRule.swift

@@ -28,7 +28,7 @@ public struct ContainsOverFilterIsEmptyRule: SwiftSyntaxRule, OptInRule, Configu
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Performance/ContainsOverRangeNilComparisonRule.swift

@@ -27,7 +27,7 @@ public struct ContainsOverRangeNilComparisonRule: SwiftSyntaxRule, OptInRule, Co
         syntaxTree.folded()
     }
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Performance/EmptyCollectionLiteralRule.swift

@@ -28,7 +28,7 @@ public struct EmptyCollectionLiteralRule: SwiftSyntaxRule, ConfigurationProvider
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Performance/EmptyStringRule.swift

@@ -24,7 +24,7 @@ public struct EmptyStringRule: ConfigurationProviderRule, OptInRule, SwiftSyntax
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Performance/FirstWhereRule.swift

@@ -32,7 +32,7 @@ public struct FirstWhereRule: SwiftSyntaxRule, OptInRule, ConfigurationProviderR
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Performance/FlatMapOverMapReduceRule.swift

@@ -19,7 +19,7 @@ public struct FlatMapOverMapReduceRule: SwiftSyntaxRule, OptInRule, Configuratio
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Performance/LastWhereRule.swift

@@ -28,7 +28,7 @@ public struct LastWhereRule: SwiftSyntaxRule, OptInRule, ConfigurationProviderRu
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Performance/ReduceBooleanRule.swift

@@ -26,7 +26,7 @@ public struct ReduceBooleanRule: SwiftSyntaxRule, ConfigurationProviderRule {
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Performance/SortedFirstLastRule.swift

@@ -42,7 +42,7 @@ public struct SortedFirstLastRule: SwiftSyntaxRule, OptInRule, ConfigurationProv
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Style/AttributesRule.swift

@@ -17,7 +17,7 @@ public struct AttributesRule: SwiftSyntaxRule, OptInRule, ConfigurationProviderR
         triggeringExamples: AttributesRuleExamples.triggeringExamples
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(
             locationConverter: file.locationConverter,
             configuration: configuration

Source/SwiftLintFramework/Rules/Style/ClosingBraceRule.swift

@@ -23,7 +23,7 @@ public struct ClosingBraceRule: SwiftSyntaxCorrectableRule, ConfigurationProvide
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 

Source/SwiftLintFramework/Rules/Style/ClosureParameterPositionRule.swift

@@ -96,7 +96,7 @@ public struct ClosureParameterPositionRule: SwiftSyntaxRule, ConfigurationProvid
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(locationConverter: file.locationConverter)
     }
 }

Source/SwiftLintFramework/Rules/Style/ClosureSpacingRule.swift

@@ -38,7 +38,7 @@ public struct ClosureSpacingRule: SwiftSyntaxCorrectableRule, ConfigurationProvi
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         ClosureSpacingRuleVisitor(locationConverter: file.locationConverter)
     }
 

Source/SwiftLintFramework/Rules/Style/ComputedAccessorsOrderRule.swift

@@ -14,7 +14,7 @@ public struct ComputedAccessorsOrderRule: ConfigurationProviderRule, SwiftSyntax
         triggeringExamples: ComputedAccessorsOrderRuleExamples.triggeringExamples
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         ComputedAccessorsOrderRuleVisitor(expectedOrder: configuration.order)
     }
 }

Source/SwiftLintFramework/Rules/Style/ConditionalReturnsOnNewlineRule.swift

@@ -34,7 +34,7 @@ public struct ConditionalReturnsOnNewlineRule: ConfigurationProviderRule, OptInR
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(
             ifOnly: configuration.ifOnly,
             locationConverter: file.locationConverter

Source/SwiftLintFramework/Rules/Style/EmptyEnumArgumentsRule.swift

@@ -107,7 +107,7 @@ public struct EmptyEnumArgumentsRule: SwiftSyntaxCorrectableRule, ConfigurationP
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 

Source/SwiftLintFramework/Rules/Style/EmptyParametersRule.swift

@@ -33,7 +33,7 @@ public struct EmptyParametersRule: SwiftSyntaxCorrectableRule, ConfigurationProv
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 

Source/SwiftLintFramework/Rules/Style/EmptyParenthesesWithTrailingClosureRule.swift

@@ -46,7 +46,7 @@ public struct EmptyParenthesesWithTrailingClosureRule: SwiftSyntaxCorrectableRul
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 

Source/SwiftLintFramework/Rules/Style/ImplicitGetterRule.swift

@@ -14,7 +14,7 @@ public struct ImplicitGetterRule: ConfigurationProviderRule, SwiftSyntaxRule {
         triggeringExamples: ImplicitGetterRuleExamples.triggeringExamples
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         ImplicitGetterRuleVisitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Style/MultipleClosuresWithTrailingClosureRule.swift

@@ -37,7 +37,7 @@ public struct MultipleClosuresWithTrailingClosureRule: SwiftSyntaxRule, Configur
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Style/NoSpaceInMethodCallRule.swift

@@ -45,7 +45,7 @@ public struct NoSpaceInMethodCallRule: SwiftSyntaxCorrectableRule, Configuration
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 

Source/SwiftLintFramework/Rules/Style/NumberSeparatorRule.swift

@@ -20,7 +20,7 @@ public struct NumberSeparatorRule: OptInRule, SwiftSyntaxCorrectableRule, Config
         corrections: NumberSeparatorRuleExamples.corrections
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(configuration: configuration)
     }
 

Source/SwiftLintFramework/Rules/Style/OperatorFunctionWhitespaceRule.swift

@@ -25,7 +25,7 @@ public struct OperatorFunctionWhitespaceRule: ConfigurationProviderRule, SwiftSy
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Style/ProtocolPropertyAccessorsOrderRule.swift

@@ -24,7 +24,7 @@ public struct ProtocolPropertyAccessorsOrderRule: ConfigurationProviderRule, Swi
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 

Source/SwiftLintFramework/Rules/Style/RedundantDiscardableLetRule.swift

@@ -28,7 +28,7 @@ public struct RedundantDiscardableLetRule: SwiftSyntaxCorrectableRule, Configura
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 

Source/SwiftLintFramework/Rules/Style/SelfBindingRule.swift

@@ -42,7 +42,7 @@ public struct SelfBindingRule: SwiftSyntaxCorrectableRule, ConfigurationProvider
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         SelfBindingRuleVisitor(bindIdentifier: configuration.bindIdentifier)
     }
 

Source/SwiftLintFramework/Rules/Style/ShorthandOperatorRule.swift

@@ -46,7 +46,7 @@ public struct ShorthandOperatorRule: ConfigurationProviderRule, SwiftSyntaxRule
         syntaxTree.folded()
     }
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }
 }

Source/SwiftLintFramework/Rules/Style/SwitchCaseOnNewlineRule.swift

@@ -62,7 +62,7 @@ public struct SwitchCaseOnNewlineRule: SwiftSyntaxRule, ConfigurationProviderRul
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(locationConverter: file.locationConverter)
     }
 }

Source/SwiftLintFramework/Rules/Style/UnneededParenthesesInClosureArgumentRule.swift

@@ -75,7 +75,7 @@ public struct UnneededParenthesesInClosureArgumentRule: ConfigurationProviderRul
         ]
     )
 
-    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor? {
+    public func makeVisitor(file: SwiftLintFile) -> ViolationsSyntaxVisitor {
         Visitor(viewMode: .sourceAccurate)
     }