Use AnyKeyPath.customDebugDescription when possible (#73)

* Use `AnyKeyPath.customDebugDescription` when possible

New in Swift 5.8 with implementation of
[SE-0369](https://github.com/apple/swift-evolution/blob/main/proposals/0369-add-customdebugdescription-conformance-to-anykeypath.md).

* Linux support.

* Linux tests

* Fix warning

* Fix

* wip

* wip

* wip

Author: stephencelis

Sources/CustomDump/Conformances/KeyPath.swift

@@ -1,6 +1,11 @@
-#if os(iOS) || os(macOS) || os(tvOS) || os(watchOS)
-  extension AnyKeyPath: CustomDumpStringConvertible {
-    public var customDumpDescription: String {
+extension AnyKeyPath: CustomDumpStringConvertible {
+  public var customDumpDescription: String {
+    #if swift(>=5.8)
+      if #available(macOS 13.3, iOS 16.4, watchOS 9.4, tvOS 16.4, *) {
+        return self.debugDescription
+      }
+    #endif
+    #if os(iOS) || os(macOS) || os(tvOS) || os(watchOS)
       guard let name = keyPathToName[self] else {
         func reflectName() -> String {
           var namedKeyPaths = Reflection.allNamedKeyPaths(forUnderlyingTypeOf: Self.rootType)
@@ -24,9 +29,13 @@
         return name
       }
       return name
-    }
+    #else
+      return typeName(Self.self, genericsAbbreviated: false)
+    #endif
   }
+}
 
+#if os(iOS) || os(macOS) || os(tvOS) || os(watchOS)
   private var keyPathToName: [AnyKeyPath: String] = [:]
 
   // The source code below was extracted from the "KeyPath Reflection" branch of Apple's

Sources/CustomDump/Internal/AnyType.swift

@@ -1,13 +1,25 @@
-func typeName(_ type: Any.Type) -> String {
-  var name = _typeName(type)
-  if let index = name.firstIndex(of: ".") {
-    name.removeSubrange(...index)
-  }
-  return
-    name
+func typeName(
+  _ type: Any.Type,
+  qualified: Bool = true,
+  genericsAbbreviated: Bool = true
+) -> String {
+  var name = _typeName(type, qualified: qualified)
+    .replacingOccurrences(
+      of: #"\w+\.(\w+)"#,
+      with: "$1",
+      options: .regularExpression
+    )
     .replacingOccurrences(
-      of: #"<.+>|\(unknown context at \$[[:xdigit:]]+\)\."#,
+      of: #"\(unknown context at \$[[:xdigit:]]+\)\."#,
       with: "",
       options: .regularExpression
     )
+  if genericsAbbreviated {
+    name = name.replacingOccurrences(
+      of: #"<.+>"#,
+      with: "",
+      options: .regularExpression
+    )
+  }
+  return name
 }

Tests/CustomDumpTests/DiffTests.swift

@@ -957,7 +957,7 @@ final class DiffTests: XCTestCase {
       diff(
         [
           "value": 29.99 as Float
-        ],
+        ] as [String: Any],
         [
           "value": 29.99 as Double
         ]

Tests/CustomDumpTests/DumpTests.swift

@@ -573,10 +573,59 @@ final class DumpTests: XCTestCase {
     )
   }
 
-  #if os(iOS) || os(macOS) || os(tvOS) || os(watchOS)
-    func testKeyPath() {
-      var dump = ""
+  func testKeyPath() {
+    var dump = ""
+
+    #if swift(>=5.8)
+      if #available(macOS 13.3, iOS 16.4, watchOS 9.4, tvOS 16.4, *) {
+        dump = ""
+        customDump(\UserClass.name, to: &dump)
+        XCTAssertNoDifference(
+          dump,
+          #"""
+          \UserClass.name
+          """#
+        )
 
+        dump = ""
+        customDump(\Pair.driver.name, to: &dump)
+        XCTAssertNoDifference(
+          dump,
+          #"""
+          \Pair.driver.name
+          """#
+        )
+
+        dump = ""
+        customDump(\User.name.count, to: &dump)
+        XCTAssertNoDifference(
+          dump,
+          #"""
+          \User.name.count
+          """#
+        )
+
+        dump = ""
+        customDump(\(x: Double, y: Double).x, to: &dump)
+        XCTAssertNoDifference(
+          dump,
+          #"""
+          \(x: Double, y: Double).x
+          """#
+        )
+
+        dump = ""
+        customDump(\Item.$isInStock, to: &dump)
+        XCTAssertNoDifference(
+          dump,
+          #"""
+          \Item.$isInStock
+          """#
+        )
+        return
+      }
+    #endif
+    #if os(iOS) || os(macOS) || os(tvOS) || os(watchOS)
       // Run twice to exercise cached lookup
       for _ in 1...2 {
         dump = ""
@@ -614,9 +663,63 @@ final class DumpTests: XCTestCase {
           WritableKeyPath<(x: Double, y: Double), Double>
           """#
         )
+
+        dump = ""
+        customDump(\Item.$isInStock, to: &dump)
+        XCTAssertNoDifference(
+          dump,
+          #"""
+          KeyPath<Item, Wrapped<Bool>>
+          """#
+        )
       }
-    }
-  #endif
+    #else
+      dump = ""
+      customDump(\UserClass.name, to: &dump)
+      XCTAssertNoDifference(
+        dump,
+        #"""
+        KeyPath<UserClass, String>
+        """#
+      )
+
+      dump = ""
+      customDump(\Pair.driver.name, to: &dump)
+      XCTAssertNoDifference(
+        dump,
+        #"""
+        KeyPath<Pair, String>
+        """#
+      )
+
+      dump = ""
+      customDump(\User.name.count, to: &dump)
+      XCTAssertNoDifference(
+        dump,
+        #"""
+        KeyPath<User, Int>
+        """#
+      )
+
+      dump = ""
+      customDump(\(x: Double, y: Double).x, to: &dump)
+      XCTAssertNoDifference(
+        dump,
+        #"""
+        WritableKeyPath<(x: Double, y: Double), Double>
+        """#
+      )
+
+      dump = ""
+      customDump(\Item.$isInStock, to: &dump)
+      XCTAssertNoDifference(
+        dump,
+        #"""
+        KeyPath<Item, Wrapped<Bool>>
+        """#
+      )
+    #endif
+  }
 
   func testNamespacedTypes() {
     var dump = ""

Tests/CustomDumpTests/Mocks.swift

@@ -129,3 +129,13 @@ struct Redacted<RawValue>: CustomDumpStringConvertible {
 
 struct User: Equatable, Identifiable { var id: Int, name: String }
 struct HashableUser: Equatable, Identifiable, Hashable { var id: Int, name: String }
+
+@propertyWrapper
+struct Wrapped<Value> {
+  var wrappedValue: Value
+  var projectedValue: Self { self }
+}
+
+struct Item {
+  @Wrapped var isInStock = true
+}