Don’t trigger redundant_void_return when using subscripts

CHANGELOG.md

@@ -14,7 +14,9 @@
 
 #### Bug Fixes
 
-* None.
+* Don't trigger `redundant_void_return` violations when using `subscript` as the
+  return type is required.  
+  [Marcelo Fabri](https://github.com/marcelofabri)
 
 ## 0.32.0: Wash-N-Fold-N-Reduce
 

Rules.md

@@ -17070,6 +17070,14 @@ func foo() -> Void!
 
 ```
 
+```swift
+struct A {
+    subscript(key: String) {
+        print(key)
+    }
+}
+```
+
 </details>
 <details>
 <summary>Triggering Examples</summary>

Source/SwiftLintFramework/Rules/Idiomatic/RedundantVoidReturnRule.swift

@@ -23,7 +23,14 @@ public struct RedundantVoidReturnRule: ConfigurationProviderRule, SubstitutionCo
             "func foo() -> ()?\n",
             "func foo() -> ()!\n",
             "func foo() -> Void?\n",
-            "func foo() -> Void!\n"
+            "func foo() -> Void!\n",
+            """
+            struct A {
+                subscript(key: String) {
+                    print(key)
+                }
+            }
+            """
         ],
         triggeringExamples: [
             "func foo()↓ -> Void {}\n",
@@ -51,6 +58,7 @@ public struct RedundantVoidReturnRule: ConfigurationProviderRule, SubstitutionCo
 
     private let pattern = "\\s*->\\s*(?:Void\\b|\\(\\s*\\))(?![?!])"
     private let excludingKinds = SyntaxKind.allKinds.subtracting([.typeidentifier])
+    private let functionKinds = SwiftDeclarationKind.functionKinds.subtracting([.functionSubscript])
 
     public func validate(file: File, kind: SwiftDeclarationKind,
                          dictionary: [String: SourceKitRepresentable]) -> [StyleViolation] {
@@ -63,7 +71,7 @@ public struct RedundantVoidReturnRule: ConfigurationProviderRule, SubstitutionCo
 
     public func violationRanges(in file: File, kind: SwiftDeclarationKind,
                                 dictionary: [String: SourceKitRepresentable]) -> [NSRange] {
-        guard SwiftDeclarationKind.functionKinds.contains(kind),
+        guard functionKinds.contains(kind),
             let nameOffset = dictionary.nameOffset,
             let nameLength = dictionary.nameLength,
             let length = dictionary.length,