fix: Reformat Visitor types to support old Swift versions

Author: NeedleInAJayStack

Tests/GraphQLTests/LanguageTests/VisitorTests.swift

@@ -8,24 +8,7 @@ class VisitorTests: XCTestCase {
     }
 
     func testValidatesPathArgument() throws {
-        struct VisitedElement: Equatable {
-            let direction: VisitDirection
-            let path: [any IndexPathElement]
-
-            init(_ direction: VisitDirection, _ path: [any IndexPathElement]) {
-                self.direction = direction
-                self.path = path
-            }
-
-            static func == (lhs: VisitedElement, rhs: VisitedElement) -> Bool {
-                return lhs.direction == rhs.direction &&
-                    zip(lhs.path, rhs.path).allSatisfy { lhs, rhs in
-                        lhs.description == rhs.description
-                    }
-            }
-        }
-
-        var visited = [VisitedElement]()
+        var visited = [VisitedPath]()
         let ast = try parse(source: "{ a }", noLocation: true)
 
         visit(root: ast, visitor: .init(
@@ -513,36 +496,7 @@ class VisitorTests: XCTestCase {
     }
 
     func testProperlyVisitsTheKitchenSinkQuery() throws {
-        struct VisitedElement: Equatable, CustomDebugStringConvertible {
-            var debugDescription: String {
-                "(\(direction), \(kind), \(key.debugDescription), \(parentKind.debugDescription))"
-            }
-
-            let direction: VisitDirection
-            let kind: Kind
-            let key: (any IndexPathElement)?
-            let parentKind: Kind?
-
-            init(
-                _ direction: VisitDirection,
-                _ kind: Kind,
-                _ key: (any IndexPathElement)?,
-                _ parentKind: Kind?
-            ) {
-                self.direction = direction
-                self.kind = kind
-                self.key = key
-                self.parentKind = parentKind
-            }
-
-            static func == (lhs: VisitedElement, rhs: VisitedElement) -> Bool {
-                return lhs.direction == rhs.direction &&
-                    lhs.kind == rhs.kind &&
-                    lhs.key?.description == rhs.key?.description &&
-                    lhs.parentKind == rhs.parentKind
-            }
-        }
-        var visited = [VisitedElement]()
+        var visited = [VisitedKindAndParent]()
 
         guard
             let url = Bundle.module.url(forResource: "kitchen-sink", withExtension: "graphql"),
@@ -884,6 +838,59 @@ enum VisitDirection: Equatable {
     case leave
 }
 
+struct VisitedPath {
+    let direction: VisitDirection
+    let path: [any IndexPathElement]
+
+    init(_ direction: VisitDirection, _ path: [any IndexPathElement]) {
+        self.direction = direction
+        self.path = path
+    }
+}
+
+extension VisitedPath: Equatable {
+    static func == (lhs: VisitedPath, rhs: VisitedPath) -> Bool {
+        return lhs.direction == rhs.direction &&
+            zip(lhs.path, rhs.path).allSatisfy { lhs, rhs in
+                lhs.description == rhs.description
+            }
+    }
+}
+
+struct VisitedKindAndParent {
+    let direction: VisitDirection
+    let kind: Kind
+    let key: (any IndexPathElement)?
+    let parentKind: Kind?
+
+    init(
+        _ direction: VisitDirection,
+        _ kind: Kind,
+        _ key: (any IndexPathElement)?,
+        _ parentKind: Kind?
+    ) {
+        self.direction = direction
+        self.kind = kind
+        self.key = key
+        self.parentKind = parentKind
+    }
+}
+
+extension VisitedKindAndParent: Equatable {
+    static func == (lhs: VisitedKindAndParent, rhs: VisitedKindAndParent) -> Bool {
+        return lhs.direction == rhs.direction &&
+            lhs.kind == rhs.kind &&
+            lhs.key?.description == rhs.key?.description &&
+            lhs.parentKind == rhs.parentKind
+    }
+}
+
+extension VisitedKindAndParent: CustomDebugStringConvertible {
+    var debugDescription: String {
+        "(\(direction), \(kind), \(key.debugDescription), \(parentKind.debugDescription))"
+    }
+}
+
 func checkVisitorFnArgs(
     _ ast: Document,
     _ node: Node,